Original Cardiovascular
Surgical Treatment of Thoracic Aortic Aneurysms in Patients with Congenital Heart Disease Dmitry Bobylev1 Dietmar Boethig1,2 Masamichi Ono1
Thomas Breymann1
1 Department of Cardiothoracic, Transplantation and Vascular
Surgery, Hannover Medical School, Hannover, Germany 2 Department of Pediatric Cardiology and Intensive Care Medicine, Hannover Medical School, Hannover, Germany
Annika Mathoni1
Alexander Horke1
Address for correspondence Dmitry Bobylev, MD, Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany (e-mail: [email protected]).
Thorac Cardiovasc Surg 2015;63:388–396.
Abstract
Keywords
► thoracic aortic aneurysm ► aortic root ► aortic valve ► repair ► congenital heart disease
Background This study we evaluate our results for surgical treatment of thoracic aortic aneurysms in patients with congenital heart disease. Patients and Methods Fifty patients aged between 12 and 71 years were treated for 51 thoracic aortic aneurysms. Forty-four of the patients developed aneurysms in the ascending aorta and seven developed aneurysms in the descending aorta. The underlying diseases for ascending aortic aneurysms included 16 congenital aortic stenosis, 16 bicuspid aortic valves, 4 transposition of the great arteries, 3 tetralogy of Fallot, 2 truncus arteriosus communis, and 3 other diseases. Patients with connective tissue disorders were excluded. All descending aortic aneurysms developed late after coarctation repair. The time interval between the correction and aneurysm operations was 15 years in ascending aneurysms and 28 years in descending aneurysms. Results The operative procedures for 44 ascending aortic aneurysms included 38 ascending aortic replacements, with or without aortic valve replacement (including 31 conduits), and 6 David operations. Graft replacement was undertaken for the seven descending aortic aneurysms. There were two hospital deaths. Forty-eight hospital survivors were in New York Heart Association functional class II or less at follow-up, which was conducted up to a maximum of 8 years after the procedure. All patients were free from reoperation and thromboembolic events. Aortic valve function was good in all six patients after the valve-sparing operation. Conclusion Thoracic aortic aneurysms in patients with congenital heart disease is highly associated with bicuspid aortic valve and aortic coarctation. For ascending aortic aneurysms, conduit replacement is the method of choice. The David procedure provides good results in selected patients. For descending aortic aneurysms, graft replacement is the preferred procedure. The relatively late development of thoracic aortic aneurysms indicates that long-term follow-up in patients with congenital heart disease, especially in patients with bicuspid aortic valve and aortic coarctation, is essential.
Introduction Thoracic aortic aneurysms can develop in association with congenital heart disease (CHD). They can also develop late
received December 17, 2013 accepted after revision February 19, 2014 published online June 25, 2014
after corrective surgery in patients with CHD. Patients with bicuspid aortic valves (BAVs) are known to develop ascending aortic aneurysms with and without aortic valve
© 2015 Georg Thieme Verlag KG Stuttgart · New York
DOI http://dx.doi.org/ 10.1055/s-0034-1376203. ISSN 0171-6425.
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Patients and Methods The need for individual study consent was waived by the Hannover Medical School Ethics Committee.
Study Population The study population consisted of 50 consecutive CHD patients with ascending or descending aorta aneurysm who underwent surgical correction at our department between August 2004 and July 2012. The age of the patients ranged from 12 to 71 years (mean age, 30.3 years), and 43 (86%) of them were male. ►Table 1 shows the patients’ characteristics. A total of 51 lesions in 50 patients were surgically treated. One patient, who underwent CoA repair at the age of 15 years, was referred to us with the diagnosis of both ascending and descending aneurysms. He underwent the David procedure following graft replacement of the descending aorta with a 4month interval (Case 31). The underlying CHDs of the patients are summarized in ►Table 2. Forty-four patients developed an ascending aortic aneurysm and seven patients developed a descending aortic aneurysm. Patients with connective tissue defect syndromes, such as Marfan syndrome, and patients with inflammatory disease (aortitis) were not included in this study. Thirty-four patients had previous surgical or interventional histories for underlying CHD (►Table 3). Three patients
Table 1 Patient profile Characteristic
n ¼ 50
Age, y (range)
30.3 13.3 (12–71)
Sex, male/female
44/6
Body height, cm (range)
174.7 12.1 (137–194)
Body weight, kg (range)
73.5 18.4 (30–114)
Maximal diameter of aneurysm, mm (range)
47.9 5.7 (40–60)
Aortic insufficiency 3 3
19
Aortic stenosis 3 3
3
Aortic valve morphology, bicuspid/tricuspid
29/21
Symptoms, þ/
23/27
389
underwent interventional procedures; two underwent a balloon dilatation of the aortic valve and the other had an interventional closure of a patent ductus arteriosus (PDA). The remaining 31 patients underwent a total of 50 operative cardiac procedures including 8 open aortic valvotomies, 4 Ross operations, 9 repairs of complex CHD, 12 repairs of the CoA, and other procedures (►Table 3). The mean interval from the most recent operation was 15.0 7.2 years (range, 3–29 years). Sixteen patients (13 patients with BAV, 1 with congenital AS, 1 with atrial septal defect (ASD), and 1 with CoA) had no history of cardiothoracic operations. The seven patients with descending aortic aneurysms all had a history of previous CoA surgery. Five patients had received a Dacron patch repair, and two patients had end-to-end anastomosis as primary operations. The mean time interval between CoA repair and aneurysm operation was 27.7 10.8 years (range, 17–51 years).
Preoperative Evaluation and Indication for Surgery All patients were followed up by our institute or associated outpatient clinic. They were referred to our unit with the diagnosis of an ascending or descending aortic aneurysm. The diagnosis at referral was confirmed by computed tomography (CT) and/or echocardiography, as appropriate. Adult patients additionally underwent cardiac catheterization with selective coronary angiography. For special indications, magnetic resonance imaging (MRI) was performed. ►Table 4 shows the type of ascending aortic aneurysm. Of the 44 patients, 28 presented with supracoronary ascending aortic aneurysms and 16 with aortic root aneurysms (►Fig. 1A). After interventional PDA closure, case 27 had an additional aortic arch aneurysm with an ascending aortic aneurysm. The maximum diameters and indices of the aneurysms expressed as the percent of normal values10 are shown in ►Table 1. Valve dysfunction (grade, moderate to severe) was seen as insufficiency in 14 patients and as stenosis in 3 patients. Eight patients displayed corresponding symptoms. For the descending aortic aneurysms, all seven of the patients had pseudoaneurysms at the site of previous CoA operations. The maximum diameter of the aneurysms ranged from 40 to 60 mm. The operative indications for the ascending aneurysms are summarized in ►Table 5. Indications for surgery in 14 patients were isolated aortic aneurysms. In the remaining 30 patients, indications for surgery were combined aortic aneurysms and aortic insufficiency (27 patients) or AS (3 patients). Eight patients required concomitant right ventricular outflow tract reconstruction (RVOTR) due to severe RVOT graft insufficiency (three patients after a Ross operation, three patients with TOF, and two patients with TAC). According to our institutional policy, aortic replacement is indicated if the aortic diameter reaches 45 mm. Severe aortic valve dysfunction associated with an aortic diameter of 40 mm or more is also considered an indication for aortic replacement. In addition, clinical symptoms were taken into consideration. Aneurysm progression was documented in six patients. In children, an aortic diameter of more than 200% of the normal measurement was considered an indication for surgery. The Thoracic and Cardiovascular Surgeon
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dysfunction.1,2 This incidence of thoracic aortic aneurysms has been well documented in patients after surgery for congenital aortic stenosis (AS),3 tetralogy of Fallot (TOF),4–6 transposition of the great arteries (TGAs),7 truncus arteriosus communis (TAC),8,9 and coarctation of the aorta (CoA).10 The natural course of these aneurysms, often without verification and diagnosis, may lead to rupture and dissection of the aorta. However, there are only a few reports on operative indications, surgical treatment, and results for thoracic aortic aneurysm in patients with CHD. We performed this study to discuss etiology, surgical indications, and techniques, as well as midterm results, of our recent experience with 50 patients following ascending or descending aorta replacement.
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Table 2 Surgical history of patients associated with congenital heart disease Patient no.
Primary diagnosis
First intervention (age)
Second intervention (age)
1
Congenital AS
Valvotomy (4 y)
2
Congenital AS
Valvotomy (5 m)
3
Congenital AS
Valvotomy (1 m)
4
Congenital AS
Balloon dilatation (5 m)
5
Congenital AS
Valvotomy (1 m)
AVR (8 y)
6
Congenital AS, CoA
CoA patch plasty (0 m)
Valvotomy (1 m)
7
Congenital AS
Valvotomy (3 m)
8
Congenital AS
Valvotomy (0 m)
Ross (15 y)
9
Congenital AS, CoA
CoA patch plasty (1 m)
Valvotomy (4 y)
10
Congenital AS
Homograft AVR (20 y)
Homograft AVR (24 y)
Third intervention (age)
AVR (12 y)
Ross (14 y)
11
Congenital AS
Balloon dilatation (8 y)
12
Congenital AS
Ross (17 y)
13
Congenital AS, CoA
CoA repair (26 y)
Ross (26 y)
14
Congenital AS
AVR (17 y)
Ao Asc patch enlargement (31 y)
15
Congenital AS (supravalvular)
Ao Asc Patch enlargement (8 y)
16
Bicuspid AV, CoA
CoA EEA (6 y)
17
Bicuspid AV, CoA
CoA patch plasty (8 m)
18
TOF/PV agenesis
Lt m-BT shunt (10 y)
TOF repair (10 y)
RVOTR (22 y)
19
TOF/PV atresia
RVOTR (2 y)
TOF repair (12 y)
RVOTR þ rest VSD (26 y)
20
TOF
TOF repair (4 y)
21
TGA/VSD
ASO (2 m)
22
TGA, CoA
CoA repair (3 m)
23
TGA
ASO (0 m)
24
TGA
ASO (0 m)
25
Truncus arteriosus
Truncus repair (2 m)
AV repair þ RVOTR (6 y)
AVR þ RVOTR (15 y)
26
Truncus arteriosus
PAB (2 m)
Truncus repair (4 y)
RVOTR (11 y)
27
PDA
Interventional closure (y)
Rest shunt occlusion (3 y)
28
CoA
CoA patch plasty (15 y)
29
CoA
CoA repair (11 y)
30
CoA
CoA repair (6 y)
31
CoA
CoA patch plasty (15 y)
32
CoA
CoA patch plasty (17 y)
33
CoA
CoA patch plasty (30 y)
34
CoA
CoA patch plasty (44 y)
Fourth intervention (age)
Mustard (y)
RVOTR þ rt.PA plasty (22 y)
Abbreviations: AA, ascending aorta; AS, aortic stenosis; ASO, arterial switch operation; AVR, aortic valve replacement; AV, aortic valve; BT, BlalockTaussig; CoA, coarctation of the aorta; EEA, end-to-end anastomosis; Lt, left; m, month; PA, pulmonary artery; PAB, pulmonary artery banding; PDA, patent ductus arteriosus; PV, pulmonary valve; rt, right; RVOTR, right ventricular outflow tract reconstruction; TOF, tetralogy of Fallot; TGA, transposition of the great arteries; VSD, ventricular septal defect; y, year.
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Table 3 Underlying disease of thoracic aortic aneurysms (n ¼ 44)
a. Ascending aortic aneurysms Other underlying disease Main underlying disease
Bicuspid AV
CoA
Number
Congenital AS (valvular)
9
3
15
16
5
16
a
1
4
(supravalvular)
1
Bicuspid aortic valve Transposition of the great arteries
2
Tetralogy of Fallot
3
Truncus arteriosus communis
2
Atrial septal defect
1
Patent ductus arteriosus
1
CoA
1
1 (n ¼ 7)
b. Descending aortic aneurysms Main underlying disease
Bicuspid AV
CoA
Number
CoA
3
7
7
Abbreviations: AV, aortic valve; AS, aortic stenosis; CoA, coarctation of the aorta. a Bicuspid neoaortic valve after arterial switch operation.
operative indication for a descending aneurysm is a maximal diameter of 40 mm or more (►Fig. 1B).
Surgical Technique Ascending aorta replacement with valved conduits (Bentall operation), valve-sparing operations, supracoronary ascending aortic replacements with and without concomitant aortic valve replacements, and graft replacements of descending aorta were performed. All patients underwent elective surgery. In cases of conduit implantation, the conduit was implanted in the aortic annulus using pledgetted 2–0 hori-
zontal mattress sutures, with the pledgets put in the subannular position. Valve-sparing procedures were performed using a 28-mm Dacron graft as standard size. We use a 26- or 30-mm graft depending on the size of the aortic annulus. Graft replacements of descending aortic aneurysms were performed using an 18- to 22-mm HEMASHIELD (Maquet Holding B.V. &Co. KG, Rastatt, Germany) polyester graft.
Follow-up Routine follow-up was performed by echocardiography at 3, 6, and 12 months, as well as CT and MRI at yearly intervals
Table 4 Type of aorta ascendance aneurysms Underlying disease
Type of aneurysms
N
Ascendance aneurysm
Root aneurysm
10
5a
15
1
1
1
16
TGA
4
4
Tetralogy of Fallot
3
3
1
2
1
1
Congenital AS
(valvular) (supravalvular)
Bicuspid aortic valve
15
Truncus arteriosus
1
PDA
1
ASD CoA
1
Total
28
1 1 16
44
Abbreviations: AS, aortic stenosis; ASD, atrial septal defect; CoA, coarctation of the aorta; PDA, patent ductus arteriosus; TGA, transposition of the great arteries. a Four autograft dilatations and one homograft dilatation. Thoracic and Cardiovascular Surgeon
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Other underlying disease
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Fig. 1 Preoperative magnetic resonance images of typical cases. (A) A 22-year-old patient with aortic root aneurysm which developed late after an arterial switch operation for the transposition of the great arteries as a newborn. (B) A 42-year-old patient with descending aortic aneurysm late after coarctation repair at the age of 15 years.
thereafter. Valve morphology, systolic and diastolic functions, was assessed in accordance with published criteria. Complications, such as infections, thromboembolism, and bleeding, were recorded as required by the guidelines of the American Association for Thoracic Surgery/Society of Thoracic Surgeons.11 The cumulative follow-up period was 2,692 months with a minimum of 3 months and a maximum of 96 months.
normally distributed variables, respectively. A p value of < 0.05 was considered statistically significant.
Results Perioperative Results Ascending Aortic Aneurysms
Statistical Analysis Using SPSS 21.0 (SPSS, Chicago, Illinois, United States), we calculated means and standard deviations of continuous variables, as well as Kaplan–Meier analyses for event-free time estimations ANOVA or Student t-tests, and Mann–Whitney tests were applied for comparisons of normally and not-
In 44 patients with ascending aortic aneurysms, a standard median sternotomy and cardiopulmonary bypass (CPB) were performed. Aortic root replacement with valved conduits (Bentall operation) was performed in 31 patients, and supracoronary ascending aortic replacement was performed in 7 patients, including a concomitant aortic valve replacement in 2 patients. The valve-sparing operation was performed in six
Table 5 Surgical indication for ascending aortic aneurysm Underlying disease Congenital AS
Indication valvular
Aneurysm only
AI (AS) þ aneurysm
5
10
15
1
1
10(3)
16
supravalvular Bicuspid aortic valve
N
3
TGA
4
Tetralogy of Fallot
3a
Truncus arteriosus
1a
4 3
1a
2
PDA
1
1
ASD
1
1
CoA Total
14
1
1
30
44
Abbreviations: AS, aortic stenosis; ASD, atrial septal defect; CoA, coarctation of the aorta; PDA, patent ductus arteriosus; TGA, transposition of the great arteries. a Pulmonary insufficiency was also the indication for operation. Thoracic and Cardiovascular Surgeon
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Table 6 Operative procedures for ascending aortic aneurysm Underlying disease
N
Procedures Conduit (GR)
Congenital AS
David
valvular
11 (4)
15
supravalvular
1
1
Bicuspid aortic valve
12 (2)
2
16
TGA
2
2
4
Tetralogy of Fallot
2
1
3
Truncus arteriosus
2
2
PDA
0 (1)
1
ASD
1
CoA
1
Total
31 (7)
1 1
6
44
patients, including two patients with BAVs, two patients with TGA, and one patient with TOF (►Table 6). In 16 patients with congenital AS, either a conduit replacement (11 patients) or supracoronary graft replacement of the ascending aorta (5 patients) was the procedure of choice. No valve-sparing operations were performed in this group. In 16 patients with BAVs, 14 patients underwent conduit replacement, 2 patients received a supracoronary graft replacement, and 2 patients underwent an aortic valve-sparing operation. Of nine patients requiring repair of complex CHD (TGA, TOF, and TAC), five patients underwent conduit replacements and three patients underwent valve-sparing operations (two patients with TGA and one with TOF). After interventional PDA closure, one patient underwent graft replacement of the ascending aorta, and proximal arch replacements were performed using short-term circulatory arrest. Patients with ASD, Myxoma, and ascending aneurysms underwent a David operation concomitant with ASD closure and Myxoma extirpation. Patients with untreated CoA underwent a conduit
replacement following CoA repair 4 months postoperatively (►Table 6). Concomitant procedures included eight subsequent RVOTR, one residual VSD closure, one ASD closure and Myxoma resection, one partial anomalus pulmonary venous connections (PAPVC) repair, and one right pulmonary artery reconstruction. In all patients, termination of CPB was uneventful and no mechanical support was required. The mean CPB and aortic cross clamp times were 196 92 minutes and 93 28 minutes, respectively. ►Table 7 shows the influence of bicuspid aortic valve (BAV) on the patients’ profile and the operative outcomes. Patients with BAV had more pronounced AS than those with tricuspid aortic valve (TAV). CPB and aortic cross clamp (AXC) times were significantly shorter in patients with BAV than in patients with TAV. There were two in-hospital deaths. One patient (Case 14) with congenital AS, who underwent aortic valve replacement at 17 years of age and patch enlargement of the ascending aorta at 31 years of age, showed reduced right and left
Table 7 Comparison of BAV and TAV in patients with ascending aortic aneurysms Factor
BAV (n ¼ 27)
TAV (n ¼ 17)
p Value
Age, y
26.4 12.8
28.5 9.1
0.57
Body weight, kg
73.3 19.3
70.7 17.1
0.65
Maximal diameter of aneurysm, mm
47.7 5.6
48.1 5.2
0.82
Percent diameter
170.6 26.1
176.6 28.6
0.48
Aortic stenosis, grade
0.96 1.1
0.24 0.54
0.008
Aortic insufficiency, grade
2.2 1.2
2.0 1.2
0.63
Graft size, mm
27.1 2.6
27.9 2.9
0.33
Cardiopulmonary bypass time, min
161.6 67.4
249.5 103.8
0.005
Aortic cross-clamp time, min
84.3 21.3
107.8 32.6
0.014
ICU stay, d
2.1 2.4
3.3 4.4
0.28
Hospital stay, d
16.9 13.3
14.1 4.2
0.42
Abbreviations: BAV, bicuspid aortic valve; ICU, intensive care unit; TAV, tricuspid aortic valve.
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Abbreviations: AS, aortic stenosis; ASD, atrial septal defect; CoA, coarctation of the aorta; PDA, patent ductus arteriosus; TGA, transposition of the great arteries.
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ventricular function preoperatively and NYHA III. She underwent mechanical conduit replacement without any intraoperative problems. After weaning from CPB, she needed a high dose of catecholamine to maintain her circulation. Postoperatively, she developed low cardiac output syndrome and died on postoperative day 6. The other patient (Case 26), who had a diagnosis of truncus arteriosus, had four previous operations showing NYHA III. Following an intraoperative lung tissue laceration that occurred during preparation, he died of respiratory failure 16 days later. All other 42 patients survived the procedure. There were no neurological complications, arrhythmia, or myocardial infarction. Six patients developed bleeding complications, requiring rethoracotomy in four patients and insertion of drainage tubes in two other patients. Three patients developed an aortic valve block III and needed pacemaker implantation. One patient developed chylothorax and needed drainage. Antibiotic therapy for wound infection was necessary in two patients. The other patient developed renal dysfunction and received diuretic therapy until his discharge day (19). In the remaining 29 patients, the postoperative course was uneventful. The average length of stay in the intensive care unit and in hospital was 2.1 days and 15.8 days, respectively.
Descending Aortic Aneurysms In seven patients with descending aortic aneurysms, graft replacement was undertaken with (six patients) and without (one patient) a left heart bypass. We cannulated the descending aorta for arterial perfusion for the lower extremities and the left atrium for venous drainage. The left subclavian artery and distal aortic arch were dissected. In all cases, the prosthetic graft was inserted without any problems. The mean bypass time was 69 20 minutes and clamp time was 53 13 minutes. No hospital deaths, perioperative stroke, arrhythmia, neurologic complication, or bleeding occurred. One patient developed respiratory insufficiency and needed ventilation for 4 days. All other patients had uneventful postoperative courses. The length of stay in the intensive care unit and in hospital was 1.8 and 10.2 days, respectively.
Follow-up All 48 patients who were discharged alive survived and were in NYHA functional class II or less during the mean follow-up time (4.3 2.4 years [range, 0.3–8 years]). There were no bleeding complications, nor any need for reoperation. In the six patients who underwent a valve-sparing operation, valve function was routinely examined. The most recent echocardiography in these patients showed minimal aortic valve insufficiency in four patients and mild insufficiency in two. The survival rate of all patients was 97.1% with 100% freedom from reoperation at 5 years postprocedure (►Fig. 2).
Discussion Thoracic aortic aneurysms can develop late after repair of CHD. Late development of an ascending aortic aneurysm and aortic root dilation is well documented in patients with CHDs, such as congenital AS,3 BAVs,1,2 TOF,4–6 TGA,7 and truncus Thoracic and Cardiovascular Surgeon
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Fig. 2 Survival in patients after surgical management of thoracic aortic aneurysms.
arteriosus.8,9 It is also well documented that aneurysms in the descending aorta can develop late after repair of CoA.10 Concerning gender association, thoracic aortic aneurysms developed more frequently in male than in female patients, which was comparable to the incidence of original CHD in the two populations. Accordingly, our patients were predominantly male (88%). The histological anomaly of these CHDs, including medial degeneration, increased matrix metalloproteinase activity, and decreased fibrillin-1 expression, is also well documented.6 However, there are few reports on surgical treatment of thoracic aortic aneurysms in association with CHD. This study describes our recent results from 50 patients who developed thoracic aortic aneurysms following surgical replacement of the ascending and descending aortas. As for the ascending aortic aneurysms, there was a tendency for the development of ascending aortic aneurysms in patients with congenital AS and BAVs. In contrast, patients with complex CHD (TGA, TOF, or TAC), so-called cono-truncal anomaly, and the patients who underwent the Ross operation instead, displayed aortic root aneurysms. We have previously reported that we considered an aortic diameter of 200% times the normal diameter as the cut-off diameter for surgical intervention for isolated aneurysms and an index of 160% times the normal index was considered the cut-off point for patients with associated severe aortic valve dysfunction or clinical symptoms.12 Concerning surgical procedures, we currently opt for conduit replacement and valve-sparing operations. In patients with isolated ascending aortic aneurysms without aortic valve function or after aortic valve replacement, graft replacement of the supracoronary ascending aorta is also indicated. In this study, all 16 patients with congenital AS underwent conduit replacement or separate ascending and aortic valve replacement. None of these patients was indicated for a valve-sparing operation because the aortic valves were not considered suitable for reimplantation. In this cohort, there were four patients who previously underwent the Ross procedure and were referred to us with the diagnosis of an aortic root aneurysm (autograft dilation). They underwent conduit replacement, with three of them needing concomitant pulmonary valve replacement.
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In this setting, a valve-sparing operation is possible,13 but it was not performed to reduce the risk of further reoperation.14 In contrast, we have recently performed valve-sparing operations in two patients with BAVs. While valve-sparing operations in patients with BAVs is controversial, a recent report has demonstrated good results.11,15–18 Since 2008, we have begun to indicate this procedure in selected patients with bicuspid valves and, so far, the valve function is good at the 45- and 58-month follow-up. Rigorous follow-up is, however, needed for these patients. Out of six patients with complex CHD, we performed a valve-sparing operation in three patients who developed root aneurysm late after corrective procedures, including repair of TOF, arterial switch operations, and a Mustard operation. In these patients, no additional reoperation was undertaken after corrective surgery, and the patients’ own aortic valves were intact. We think the indication for this procedure should be strictly limited to patients with complex CHD because their expected lifespan is long. The risk of reoperation and pathology of coexistent RVOT lesions should also be taken into account.12 Our contraindications for David operation include marked leaflet fenestration and asymmetry, marked leaflet irregularities, or bicuspid valve with extensive calcification or severe prolapse. Surgeon experience is also very important for outcome following valve-sparing operation. We used only technique of valve reimplantation within a straight-tube Dacron graft (David I). We have no experience with the remodeling procedure for aortic root (Yacoub operation) in patients with CHD. The modified David V technique for resuspending the aortic valve within a Dacron graft with prefashioned pseudosinuses (Gelweave Valsalva graft, Gelweave Valsalva, VASCUTEK Company, Inchinnan, Scotland, UK) may become the gut option for these patients.19 The remaining six patients underwent mechanical valved conduit replacements, and in five of these patients, the RVOT conduit was changed concomitantly. The timing of surgery should be considered for both aortic and pulmonary lesions because reoperation after repeated surgeries (a total of 19 times for nine patients) results in considerable risks for the patients. The main reason for choosing a mechanical conduit was to minimize the risk of further reoperations. For the descending aortic aneurysms, the late development of aneurysms after repair of aortic coarctation is well documented, and aneurysms in this lesion can develop slowly.10 In our experience with seven patients, the mean interval between the initial coarctation repair and aneurysm operation is 28 years. Recently, endovascular management of descending aortic aneurysms has emerged as an evolving technology, and it has been applied for pseudoaneurysms after previous surgical repair of coarctation.20–22 Stent graft therapy has some advantages over surgical treatment, such as granting less invasive access to the target lesion, resulting in shorter hospital stays, and minimal pain for the patient. Endovascular stent therapy may become the preferred option for this lesion in the near future. However, our study demonstrated excellent results for surgical treatment, suggesting that surgical therapy still remains a good option for the treatment of this lesion.
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The mean aortic clamp time was 53 13 minutes. This is considerably longer than the safety limit for aortic occlusion; therefore, six from seven patients were operated with CPB. Left heart bypass can provide sufficient perfusion of the circulation distal to the aortic cross-clamp and decrease the incident of postoperative paraplegia. Same authors used CPB with venous cannulation via the main pulmonary artery, below the pulmonary bifurcation, to prevent air embolism after air entry into the left atrium.23 In our experience, however, no complications after left heart circulation have been observed. In this study, more than half of the patients (29 of 50, 58%) had BAVs. In addition to the 16 isolated BAV patients, we observed a BAV in 9 of 16 patients with congenital AS, 2 of 4 patients with TGAs, and 3 of 7 patients with descending aortic aneurysms. Thoracic aortic disease in patients with BAVs is well documented,24,25 and molecular abnormality of the aortic wall of BAV has also been reported.26 Our results, even with the small number of patients, suggest that the presence of a BAV, including neo BAV combined with other CHDs, is also a long-term risk factor for aortic aneurysms. Careful long-term follow-up is mandatory for this cohort. On the contrary, 10 out of 44 patients with ascending aortic aneurysms were associated with CoA. In their recent study, Preventza et al reported coarctationassociated aortic aneurysms.27 Thoracic aortic aneurysms occurred in the descending aorta, in the ascending aorta, and in the left subclavian artery. They also reported multiple aneurysms and a high rate of association with BAV (45.4%). In our series, one patient was referred to us with the diagnosis of ascending and descending aortic aneurysms, who underwent coarctation repair at the age of 15 years. As for the association of coarctation and BAV, seven of the ten patients with ascending aortic aneurysms and coarctation had BAV, and three of the seven patients with descending aneurysm after CoA repair had BAV. This fact suggests a multiplier effect of CoA and BAV for the development of a thoracic aortic aneurysm. In conclusion, our results demonstrate that thoracic aortic aneurysms can develop in patients with various kinds of CHD. These predominantly developed in male patients, and are highly associated with BAV and aortic coarctation. In terms of surgical treatment, replacement with a composite graft is the standard procedure for ascending aortic aneurysms. A valve-sparing operation can be performed in selected patients with aortic root dilation after surgery for complex CHD and also in selected patients with BAVs. Graft replacement using a CPB is the standard procedure for descending aortic aneurysms. Midterm results were excellent for both ascending and descending aortic aneurysms.
Note This article was presented at the 42th annual meeting of the German Society for Thoracic and Cardiovascular Surgery in Freiburg, Germany, February 18, 2013.
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Surgical Treatment of Thoracic Aortic Aneurysms
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Acknowledgments Parts of this paper (in the “Patients and Methods” and “Results” sections) are reprinted from Ono M, Goerler H, Boethig D, Westhoff-Bleck M, Breymann T. Current surgical management of ascending aortic aneurysm in children and young adults. Ann Thorac Surg 2009;88(5):1527-1533, with kind permission from Elsevier.
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nary autograft and aortic regurgitation after the Ross procedure. Ann Thorac Surg 2003;75(5):1518–1522 Ono M, Goerler H, Boethig D, Westhoff-Bleck M, Breymann T. Combined aortic root and right ventricular outflow tract replacement with mechanical conduits in adult patients after repeated surgery for congenital heart disease. Thorac Cardiovasc Surg 2009; 57(7):395–398 Kari FA, Liang DH, Kvitting JP, et al. Tirone David valve-sparing aortic root replacement and cusp repair for bicuspid aortic valve disease. J Thorac Cardiovasc Surg 2013;145(3, Suppl):S35–S40. e1-2 Kvitting JP, Kari FA, Fischbein MP, et al. David valve-sparing aortic root replacement: equivalent mid-term outcome for different valve types with or without connective tissue disorder. J Thorac Cardiovasc Surg 2013;145(1):117–126, e1–e5, discussion 126– 127 Tweddell JS, Earing MG, Bartz PJ, Dunham-Ingles JL, Woods RK, Mitchell ME. Valve-sparing aortic root reconstruction in children, teenagers, and young adults. Ann Thorac Surg 2012;94(2): 587–590, discussion 590–591 Schäfers HJ, Kunihara T, Fries P, Brittner B, Aicher D. Valvepreserving root replacement in bicuspid aortic valves. J Thorac Cardiovasc Surg 2010;140(6, Suppl):S36–S40, discussion S45–S51 Patel ND, Arnaoutakis GJ, George TJ, et al. Valve-sparing aortic root replacement in children: intermediate-term results. Interact Cardiovasc Thorac Surg 2011;12(3):415–419, discussion 419 Marcheix B, Lamarche Y, Perrault P, et al. Endovascular management of pseudo-aneurysms after previous surgical repair of congenital aortic coarctation. Eur J Cardiothorac Surg 2007; 31(6):1004–1007 Sandrio S, Karck M, Gorenflo M, Loukanov T. Results of using cardiopulmonary bypass for spinal cord protection during surgical repair of complex aortic coarctation. Cardiol Young 2014;24(1): 113–119 Botta L, Russo V, Oppido G, et al. Role of endovascular repair in the management of late pseudo-aneurysms following open surgery for aortic coarctation. Eur J Cardiothorac Surg 2009;36(4): 670–674 Kutty S, Greenberg RK, Fletcher S, Svensson LG, Latson LA. Endovascular stent grafts for large thoracic aneurysms after coarctation repair. Ann Thorac Surg 2008;85(4):1332–1338 Girdauskas E, Disha K, Borger MA, Kuntze T. Long-term prognosis of ascending aortic aneurysm after aortic valve replacement for bicuspid versus tricuspid aortic valve stenosis. J Thorac Cardiovasc Surg 2014;147(1):276–282 Svensson LG, Kim KH, Blackstone EH, et al. Bicuspid aortic valve surgery with proactive ascending aorta repair. J Thorac Cardiovasc Surg 2011;142(3):622–629, e1–e3 Ikonomidis JS, Jones JA, Barbour JR, et al. Expression of matrix metalloproteinases and endogenous inhibitors within ascending aortic aneurysms of patients with bicuspid or tricuspid aortic valves. J Thorac Cardiovasc Surg 2007;133(4):1028–1036 Preventza O, Livesay JJ, Cooley DA, Krajcer Z, Cheong BY, Coselli JS. Coarctation-associated aneurysms: a localized disease or diffuse aortopathy. Ann Thorac Surg 2013;95(6):1961–1967, discussion 1967
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Surgical Treatment of Thoracic Aortic Aneurysms in Patients with Congenital Heart Disease Dmitry Bobylev1 Dietmar Boethig1,2 Masamichi Ono1
Thomas Breymann1
1 Department of Cardiothoracic, Transplantation and Vascular
Surgery, Hannover Medical School, Hannover, Germany 2 Department of Pediatric Cardiology and Intensive Care Medicine, Hannover Medical School, Hannover, Germany
Annika Mathoni1
Alexander Horke1
Address for correspondence Dmitry Bobylev, MD, Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany (e-mail: [email protected]).
Thorac Cardiovasc Surg 2015;63:388–396.
Abstract
Keywords
► thoracic aortic aneurysm ► aortic root ► aortic valve ► repair ► congenital heart disease
Background This study we evaluate our results for surgical treatment of thoracic aortic aneurysms in patients with congenital heart disease. Patients and Methods Fifty patients aged between 12 and 71 years were treated for 51 thoracic aortic aneurysms. Forty-four of the patients developed aneurysms in the ascending aorta and seven developed aneurysms in the descending aorta. The underlying diseases for ascending aortic aneurysms included 16 congenital aortic stenosis, 16 bicuspid aortic valves, 4 transposition of the great arteries, 3 tetralogy of Fallot, 2 truncus arteriosus communis, and 3 other diseases. Patients with connective tissue disorders were excluded. All descending aortic aneurysms developed late after coarctation repair. The time interval between the correction and aneurysm operations was 15 years in ascending aneurysms and 28 years in descending aneurysms. Results The operative procedures for 44 ascending aortic aneurysms included 38 ascending aortic replacements, with or without aortic valve replacement (including 31 conduits), and 6 David operations. Graft replacement was undertaken for the seven descending aortic aneurysms. There were two hospital deaths. Forty-eight hospital survivors were in New York Heart Association functional class II or less at follow-up, which was conducted up to a maximum of 8 years after the procedure. All patients were free from reoperation and thromboembolic events. Aortic valve function was good in all six patients after the valve-sparing operation. Conclusion Thoracic aortic aneurysms in patients with congenital heart disease is highly associated with bicuspid aortic valve and aortic coarctation. For ascending aortic aneurysms, conduit replacement is the method of choice. The David procedure provides good results in selected patients. For descending aortic aneurysms, graft replacement is the preferred procedure. The relatively late development of thoracic aortic aneurysms indicates that long-term follow-up in patients with congenital heart disease, especially in patients with bicuspid aortic valve and aortic coarctation, is essential.
Introduction Thoracic aortic aneurysms can develop in association with congenital heart disease (CHD). They can also develop late
received December 17, 2013 accepted after revision February 19, 2014 published online June 25, 2014
after corrective surgery in patients with CHD. Patients with bicuspid aortic valves (BAVs) are known to develop ascending aortic aneurysms with and without aortic valve
© 2015 Georg Thieme Verlag KG Stuttgart · New York
DOI http://dx.doi.org/ 10.1055/s-0034-1376203. ISSN 0171-6425.
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Surgical Treatment of Thoracic Aortic Aneurysms
Patients and Methods The need for individual study consent was waived by the Hannover Medical School Ethics Committee.
Study Population The study population consisted of 50 consecutive CHD patients with ascending or descending aorta aneurysm who underwent surgical correction at our department between August 2004 and July 2012. The age of the patients ranged from 12 to 71 years (mean age, 30.3 years), and 43 (86%) of them were male. ►Table 1 shows the patients’ characteristics. A total of 51 lesions in 50 patients were surgically treated. One patient, who underwent CoA repair at the age of 15 years, was referred to us with the diagnosis of both ascending and descending aneurysms. He underwent the David procedure following graft replacement of the descending aorta with a 4month interval (Case 31). The underlying CHDs of the patients are summarized in ►Table 2. Forty-four patients developed an ascending aortic aneurysm and seven patients developed a descending aortic aneurysm. Patients with connective tissue defect syndromes, such as Marfan syndrome, and patients with inflammatory disease (aortitis) were not included in this study. Thirty-four patients had previous surgical or interventional histories for underlying CHD (►Table 3). Three patients
Table 1 Patient profile Characteristic
n ¼ 50
Age, y (range)
30.3 13.3 (12–71)
Sex, male/female
44/6
Body height, cm (range)
174.7 12.1 (137–194)
Body weight, kg (range)
73.5 18.4 (30–114)
Maximal diameter of aneurysm, mm (range)
47.9 5.7 (40–60)
Aortic insufficiency 3 3
19
Aortic stenosis 3 3
3
Aortic valve morphology, bicuspid/tricuspid
29/21
Symptoms, þ/
23/27
389
underwent interventional procedures; two underwent a balloon dilatation of the aortic valve and the other had an interventional closure of a patent ductus arteriosus (PDA). The remaining 31 patients underwent a total of 50 operative cardiac procedures including 8 open aortic valvotomies, 4 Ross operations, 9 repairs of complex CHD, 12 repairs of the CoA, and other procedures (►Table 3). The mean interval from the most recent operation was 15.0 7.2 years (range, 3–29 years). Sixteen patients (13 patients with BAV, 1 with congenital AS, 1 with atrial septal defect (ASD), and 1 with CoA) had no history of cardiothoracic operations. The seven patients with descending aortic aneurysms all had a history of previous CoA surgery. Five patients had received a Dacron patch repair, and two patients had end-to-end anastomosis as primary operations. The mean time interval between CoA repair and aneurysm operation was 27.7 10.8 years (range, 17–51 years).
Preoperative Evaluation and Indication for Surgery All patients were followed up by our institute or associated outpatient clinic. They were referred to our unit with the diagnosis of an ascending or descending aortic aneurysm. The diagnosis at referral was confirmed by computed tomography (CT) and/or echocardiography, as appropriate. Adult patients additionally underwent cardiac catheterization with selective coronary angiography. For special indications, magnetic resonance imaging (MRI) was performed. ►Table 4 shows the type of ascending aortic aneurysm. Of the 44 patients, 28 presented with supracoronary ascending aortic aneurysms and 16 with aortic root aneurysms (►Fig. 1A). After interventional PDA closure, case 27 had an additional aortic arch aneurysm with an ascending aortic aneurysm. The maximum diameters and indices of the aneurysms expressed as the percent of normal values10 are shown in ►Table 1. Valve dysfunction (grade, moderate to severe) was seen as insufficiency in 14 patients and as stenosis in 3 patients. Eight patients displayed corresponding symptoms. For the descending aortic aneurysms, all seven of the patients had pseudoaneurysms at the site of previous CoA operations. The maximum diameter of the aneurysms ranged from 40 to 60 mm. The operative indications for the ascending aneurysms are summarized in ►Table 5. Indications for surgery in 14 patients were isolated aortic aneurysms. In the remaining 30 patients, indications for surgery were combined aortic aneurysms and aortic insufficiency (27 patients) or AS (3 patients). Eight patients required concomitant right ventricular outflow tract reconstruction (RVOTR) due to severe RVOT graft insufficiency (three patients after a Ross operation, three patients with TOF, and two patients with TAC). According to our institutional policy, aortic replacement is indicated if the aortic diameter reaches 45 mm. Severe aortic valve dysfunction associated with an aortic diameter of 40 mm or more is also considered an indication for aortic replacement. In addition, clinical symptoms were taken into consideration. Aneurysm progression was documented in six patients. In children, an aortic diameter of more than 200% of the normal measurement was considered an indication for surgery. The Thoracic and Cardiovascular Surgeon
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dysfunction.1,2 This incidence of thoracic aortic aneurysms has been well documented in patients after surgery for congenital aortic stenosis (AS),3 tetralogy of Fallot (TOF),4–6 transposition of the great arteries (TGAs),7 truncus arteriosus communis (TAC),8,9 and coarctation of the aorta (CoA).10 The natural course of these aneurysms, often without verification and diagnosis, may lead to rupture and dissection of the aorta. However, there are only a few reports on operative indications, surgical treatment, and results for thoracic aortic aneurysm in patients with CHD. We performed this study to discuss etiology, surgical indications, and techniques, as well as midterm results, of our recent experience with 50 patients following ascending or descending aorta replacement.
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Table 2 Surgical history of patients associated with congenital heart disease Patient no.
Primary diagnosis
First intervention (age)
Second intervention (age)
1
Congenital AS
Valvotomy (4 y)
2
Congenital AS
Valvotomy (5 m)
3
Congenital AS
Valvotomy (1 m)
4
Congenital AS
Balloon dilatation (5 m)
5
Congenital AS
Valvotomy (1 m)
AVR (8 y)
6
Congenital AS, CoA
CoA patch plasty (0 m)
Valvotomy (1 m)
7
Congenital AS
Valvotomy (3 m)
8
Congenital AS
Valvotomy (0 m)
Ross (15 y)
9
Congenital AS, CoA
CoA patch plasty (1 m)
Valvotomy (4 y)
10
Congenital AS
Homograft AVR (20 y)
Homograft AVR (24 y)
Third intervention (age)
AVR (12 y)
Ross (14 y)
11
Congenital AS
Balloon dilatation (8 y)
12
Congenital AS
Ross (17 y)
13
Congenital AS, CoA
CoA repair (26 y)
Ross (26 y)
14
Congenital AS
AVR (17 y)
Ao Asc patch enlargement (31 y)
15
Congenital AS (supravalvular)
Ao Asc Patch enlargement (8 y)
16
Bicuspid AV, CoA
CoA EEA (6 y)
17
Bicuspid AV, CoA
CoA patch plasty (8 m)
18
TOF/PV agenesis
Lt m-BT shunt (10 y)
TOF repair (10 y)
RVOTR (22 y)
19
TOF/PV atresia
RVOTR (2 y)
TOF repair (12 y)
RVOTR þ rest VSD (26 y)
20
TOF
TOF repair (4 y)
21
TGA/VSD
ASO (2 m)
22
TGA, CoA
CoA repair (3 m)
23
TGA
ASO (0 m)
24
TGA
ASO (0 m)
25
Truncus arteriosus
Truncus repair (2 m)
AV repair þ RVOTR (6 y)
AVR þ RVOTR (15 y)
26
Truncus arteriosus
PAB (2 m)
Truncus repair (4 y)
RVOTR (11 y)
27
PDA
Interventional closure (y)
Rest shunt occlusion (3 y)
28
CoA
CoA patch plasty (15 y)
29
CoA
CoA repair (11 y)
30
CoA
CoA repair (6 y)
31
CoA
CoA patch plasty (15 y)
32
CoA
CoA patch plasty (17 y)
33
CoA
CoA patch plasty (30 y)
34
CoA
CoA patch plasty (44 y)
Fourth intervention (age)
Mustard (y)
RVOTR þ rt.PA plasty (22 y)
Abbreviations: AA, ascending aorta; AS, aortic stenosis; ASO, arterial switch operation; AVR, aortic valve replacement; AV, aortic valve; BT, BlalockTaussig; CoA, coarctation of the aorta; EEA, end-to-end anastomosis; Lt, left; m, month; PA, pulmonary artery; PAB, pulmonary artery banding; PDA, patent ductus arteriosus; PV, pulmonary valve; rt, right; RVOTR, right ventricular outflow tract reconstruction; TOF, tetralogy of Fallot; TGA, transposition of the great arteries; VSD, ventricular septal defect; y, year.
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Table 3 Underlying disease of thoracic aortic aneurysms (n ¼ 44)
a. Ascending aortic aneurysms Other underlying disease Main underlying disease
Bicuspid AV
CoA
Number
Congenital AS (valvular)
9
3
15
16
5
16
a
1
4
(supravalvular)
1
Bicuspid aortic valve Transposition of the great arteries
2
Tetralogy of Fallot
3
Truncus arteriosus communis
2
Atrial septal defect
1
Patent ductus arteriosus
1
CoA
1
1 (n ¼ 7)
b. Descending aortic aneurysms Main underlying disease
Bicuspid AV
CoA
Number
CoA
3
7
7
Abbreviations: AV, aortic valve; AS, aortic stenosis; CoA, coarctation of the aorta. a Bicuspid neoaortic valve after arterial switch operation.
operative indication for a descending aneurysm is a maximal diameter of 40 mm or more (►Fig. 1B).
Surgical Technique Ascending aorta replacement with valved conduits (Bentall operation), valve-sparing operations, supracoronary ascending aortic replacements with and without concomitant aortic valve replacements, and graft replacements of descending aorta were performed. All patients underwent elective surgery. In cases of conduit implantation, the conduit was implanted in the aortic annulus using pledgetted 2–0 hori-
zontal mattress sutures, with the pledgets put in the subannular position. Valve-sparing procedures were performed using a 28-mm Dacron graft as standard size. We use a 26- or 30-mm graft depending on the size of the aortic annulus. Graft replacements of descending aortic aneurysms were performed using an 18- to 22-mm HEMASHIELD (Maquet Holding B.V. &Co. KG, Rastatt, Germany) polyester graft.
Follow-up Routine follow-up was performed by echocardiography at 3, 6, and 12 months, as well as CT and MRI at yearly intervals
Table 4 Type of aorta ascendance aneurysms Underlying disease
Type of aneurysms
N
Ascendance aneurysm
Root aneurysm
10
5a
15
1
1
1
16
TGA
4
4
Tetralogy of Fallot
3
3
1
2
1
1
Congenital AS
(valvular) (supravalvular)
Bicuspid aortic valve
15
Truncus arteriosus
1
PDA
1
ASD CoA
1
Total
28
1 1 16
44
Abbreviations: AS, aortic stenosis; ASD, atrial septal defect; CoA, coarctation of the aorta; PDA, patent ductus arteriosus; TGA, transposition of the great arteries. a Four autograft dilatations and one homograft dilatation. Thoracic and Cardiovascular Surgeon
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Other underlying disease
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Fig. 1 Preoperative magnetic resonance images of typical cases. (A) A 22-year-old patient with aortic root aneurysm which developed late after an arterial switch operation for the transposition of the great arteries as a newborn. (B) A 42-year-old patient with descending aortic aneurysm late after coarctation repair at the age of 15 years.
thereafter. Valve morphology, systolic and diastolic functions, was assessed in accordance with published criteria. Complications, such as infections, thromboembolism, and bleeding, were recorded as required by the guidelines of the American Association for Thoracic Surgery/Society of Thoracic Surgeons.11 The cumulative follow-up period was 2,692 months with a minimum of 3 months and a maximum of 96 months.
normally distributed variables, respectively. A p value of < 0.05 was considered statistically significant.
Results Perioperative Results Ascending Aortic Aneurysms
Statistical Analysis Using SPSS 21.0 (SPSS, Chicago, Illinois, United States), we calculated means and standard deviations of continuous variables, as well as Kaplan–Meier analyses for event-free time estimations ANOVA or Student t-tests, and Mann–Whitney tests were applied for comparisons of normally and not-
In 44 patients with ascending aortic aneurysms, a standard median sternotomy and cardiopulmonary bypass (CPB) were performed. Aortic root replacement with valved conduits (Bentall operation) was performed in 31 patients, and supracoronary ascending aortic replacement was performed in 7 patients, including a concomitant aortic valve replacement in 2 patients. The valve-sparing operation was performed in six
Table 5 Surgical indication for ascending aortic aneurysm Underlying disease Congenital AS
Indication valvular
Aneurysm only
AI (AS) þ aneurysm
5
10
15
1
1
10(3)
16
supravalvular Bicuspid aortic valve
N
3
TGA
4
Tetralogy of Fallot
3a
Truncus arteriosus
1a
4 3
1a
2
PDA
1
1
ASD
1
1
CoA Total
14
1
1
30
44
Abbreviations: AS, aortic stenosis; ASD, atrial septal defect; CoA, coarctation of the aorta; PDA, patent ductus arteriosus; TGA, transposition of the great arteries. a Pulmonary insufficiency was also the indication for operation. Thoracic and Cardiovascular Surgeon
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Table 6 Operative procedures for ascending aortic aneurysm Underlying disease
N
Procedures Conduit (GR)
Congenital AS
David
valvular
11 (4)
15
supravalvular
1
1
Bicuspid aortic valve
12 (2)
2
16
TGA
2
2
4
Tetralogy of Fallot
2
1
3
Truncus arteriosus
2
2
PDA
0 (1)
1
ASD
1
CoA
1
Total
31 (7)
1 1
6
44
patients, including two patients with BAVs, two patients with TGA, and one patient with TOF (►Table 6). In 16 patients with congenital AS, either a conduit replacement (11 patients) or supracoronary graft replacement of the ascending aorta (5 patients) was the procedure of choice. No valve-sparing operations were performed in this group. In 16 patients with BAVs, 14 patients underwent conduit replacement, 2 patients received a supracoronary graft replacement, and 2 patients underwent an aortic valve-sparing operation. Of nine patients requiring repair of complex CHD (TGA, TOF, and TAC), five patients underwent conduit replacements and three patients underwent valve-sparing operations (two patients with TGA and one with TOF). After interventional PDA closure, one patient underwent graft replacement of the ascending aorta, and proximal arch replacements were performed using short-term circulatory arrest. Patients with ASD, Myxoma, and ascending aneurysms underwent a David operation concomitant with ASD closure and Myxoma extirpation. Patients with untreated CoA underwent a conduit
replacement following CoA repair 4 months postoperatively (►Table 6). Concomitant procedures included eight subsequent RVOTR, one residual VSD closure, one ASD closure and Myxoma resection, one partial anomalus pulmonary venous connections (PAPVC) repair, and one right pulmonary artery reconstruction. In all patients, termination of CPB was uneventful and no mechanical support was required. The mean CPB and aortic cross clamp times were 196 92 minutes and 93 28 minutes, respectively. ►Table 7 shows the influence of bicuspid aortic valve (BAV) on the patients’ profile and the operative outcomes. Patients with BAV had more pronounced AS than those with tricuspid aortic valve (TAV). CPB and aortic cross clamp (AXC) times were significantly shorter in patients with BAV than in patients with TAV. There were two in-hospital deaths. One patient (Case 14) with congenital AS, who underwent aortic valve replacement at 17 years of age and patch enlargement of the ascending aorta at 31 years of age, showed reduced right and left
Table 7 Comparison of BAV and TAV in patients with ascending aortic aneurysms Factor
BAV (n ¼ 27)
TAV (n ¼ 17)
p Value
Age, y
26.4 12.8
28.5 9.1
0.57
Body weight, kg
73.3 19.3
70.7 17.1
0.65
Maximal diameter of aneurysm, mm
47.7 5.6
48.1 5.2
0.82
Percent diameter
170.6 26.1
176.6 28.6
0.48
Aortic stenosis, grade
0.96 1.1
0.24 0.54
0.008
Aortic insufficiency, grade
2.2 1.2
2.0 1.2
0.63
Graft size, mm
27.1 2.6
27.9 2.9
0.33
Cardiopulmonary bypass time, min
161.6 67.4
249.5 103.8
0.005
Aortic cross-clamp time, min
84.3 21.3
107.8 32.6
0.014
ICU stay, d
2.1 2.4
3.3 4.4
0.28
Hospital stay, d
16.9 13.3
14.1 4.2
0.42
Abbreviations: BAV, bicuspid aortic valve; ICU, intensive care unit; TAV, tricuspid aortic valve.
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Abbreviations: AS, aortic stenosis; ASD, atrial septal defect; CoA, coarctation of the aorta; PDA, patent ductus arteriosus; TGA, transposition of the great arteries.
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ventricular function preoperatively and NYHA III. She underwent mechanical conduit replacement without any intraoperative problems. After weaning from CPB, she needed a high dose of catecholamine to maintain her circulation. Postoperatively, she developed low cardiac output syndrome and died on postoperative day 6. The other patient (Case 26), who had a diagnosis of truncus arteriosus, had four previous operations showing NYHA III. Following an intraoperative lung tissue laceration that occurred during preparation, he died of respiratory failure 16 days later. All other 42 patients survived the procedure. There were no neurological complications, arrhythmia, or myocardial infarction. Six patients developed bleeding complications, requiring rethoracotomy in four patients and insertion of drainage tubes in two other patients. Three patients developed an aortic valve block III and needed pacemaker implantation. One patient developed chylothorax and needed drainage. Antibiotic therapy for wound infection was necessary in two patients. The other patient developed renal dysfunction and received diuretic therapy until his discharge day (19). In the remaining 29 patients, the postoperative course was uneventful. The average length of stay in the intensive care unit and in hospital was 2.1 days and 15.8 days, respectively.
Descending Aortic Aneurysms In seven patients with descending aortic aneurysms, graft replacement was undertaken with (six patients) and without (one patient) a left heart bypass. We cannulated the descending aorta for arterial perfusion for the lower extremities and the left atrium for venous drainage. The left subclavian artery and distal aortic arch were dissected. In all cases, the prosthetic graft was inserted without any problems. The mean bypass time was 69 20 minutes and clamp time was 53 13 minutes. No hospital deaths, perioperative stroke, arrhythmia, neurologic complication, or bleeding occurred. One patient developed respiratory insufficiency and needed ventilation for 4 days. All other patients had uneventful postoperative courses. The length of stay in the intensive care unit and in hospital was 1.8 and 10.2 days, respectively.
Follow-up All 48 patients who were discharged alive survived and were in NYHA functional class II or less during the mean follow-up time (4.3 2.4 years [range, 0.3–8 years]). There were no bleeding complications, nor any need for reoperation. In the six patients who underwent a valve-sparing operation, valve function was routinely examined. The most recent echocardiography in these patients showed minimal aortic valve insufficiency in four patients and mild insufficiency in two. The survival rate of all patients was 97.1% with 100% freedom from reoperation at 5 years postprocedure (►Fig. 2).
Discussion Thoracic aortic aneurysms can develop late after repair of CHD. Late development of an ascending aortic aneurysm and aortic root dilation is well documented in patients with CHDs, such as congenital AS,3 BAVs,1,2 TOF,4–6 TGA,7 and truncus Thoracic and Cardiovascular Surgeon
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Fig. 2 Survival in patients after surgical management of thoracic aortic aneurysms.
arteriosus.8,9 It is also well documented that aneurysms in the descending aorta can develop late after repair of CoA.10 Concerning gender association, thoracic aortic aneurysms developed more frequently in male than in female patients, which was comparable to the incidence of original CHD in the two populations. Accordingly, our patients were predominantly male (88%). The histological anomaly of these CHDs, including medial degeneration, increased matrix metalloproteinase activity, and decreased fibrillin-1 expression, is also well documented.6 However, there are few reports on surgical treatment of thoracic aortic aneurysms in association with CHD. This study describes our recent results from 50 patients who developed thoracic aortic aneurysms following surgical replacement of the ascending and descending aortas. As for the ascending aortic aneurysms, there was a tendency for the development of ascending aortic aneurysms in patients with congenital AS and BAVs. In contrast, patients with complex CHD (TGA, TOF, or TAC), so-called cono-truncal anomaly, and the patients who underwent the Ross operation instead, displayed aortic root aneurysms. We have previously reported that we considered an aortic diameter of 200% times the normal diameter as the cut-off diameter for surgical intervention for isolated aneurysms and an index of 160% times the normal index was considered the cut-off point for patients with associated severe aortic valve dysfunction or clinical symptoms.12 Concerning surgical procedures, we currently opt for conduit replacement and valve-sparing operations. In patients with isolated ascending aortic aneurysms without aortic valve function or after aortic valve replacement, graft replacement of the supracoronary ascending aorta is also indicated. In this study, all 16 patients with congenital AS underwent conduit replacement or separate ascending and aortic valve replacement. None of these patients was indicated for a valve-sparing operation because the aortic valves were not considered suitable for reimplantation. In this cohort, there were four patients who previously underwent the Ross procedure and were referred to us with the diagnosis of an aortic root aneurysm (autograft dilation). They underwent conduit replacement, with three of them needing concomitant pulmonary valve replacement.
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In this setting, a valve-sparing operation is possible,13 but it was not performed to reduce the risk of further reoperation.14 In contrast, we have recently performed valve-sparing operations in two patients with BAVs. While valve-sparing operations in patients with BAVs is controversial, a recent report has demonstrated good results.11,15–18 Since 2008, we have begun to indicate this procedure in selected patients with bicuspid valves and, so far, the valve function is good at the 45- and 58-month follow-up. Rigorous follow-up is, however, needed for these patients. Out of six patients with complex CHD, we performed a valve-sparing operation in three patients who developed root aneurysm late after corrective procedures, including repair of TOF, arterial switch operations, and a Mustard operation. In these patients, no additional reoperation was undertaken after corrective surgery, and the patients’ own aortic valves were intact. We think the indication for this procedure should be strictly limited to patients with complex CHD because their expected lifespan is long. The risk of reoperation and pathology of coexistent RVOT lesions should also be taken into account.12 Our contraindications for David operation include marked leaflet fenestration and asymmetry, marked leaflet irregularities, or bicuspid valve with extensive calcification or severe prolapse. Surgeon experience is also very important for outcome following valve-sparing operation. We used only technique of valve reimplantation within a straight-tube Dacron graft (David I). We have no experience with the remodeling procedure for aortic root (Yacoub operation) in patients with CHD. The modified David V technique for resuspending the aortic valve within a Dacron graft with prefashioned pseudosinuses (Gelweave Valsalva graft, Gelweave Valsalva, VASCUTEK Company, Inchinnan, Scotland, UK) may become the gut option for these patients.19 The remaining six patients underwent mechanical valved conduit replacements, and in five of these patients, the RVOT conduit was changed concomitantly. The timing of surgery should be considered for both aortic and pulmonary lesions because reoperation after repeated surgeries (a total of 19 times for nine patients) results in considerable risks for the patients. The main reason for choosing a mechanical conduit was to minimize the risk of further reoperations. For the descending aortic aneurysms, the late development of aneurysms after repair of aortic coarctation is well documented, and aneurysms in this lesion can develop slowly.10 In our experience with seven patients, the mean interval between the initial coarctation repair and aneurysm operation is 28 years. Recently, endovascular management of descending aortic aneurysms has emerged as an evolving technology, and it has been applied for pseudoaneurysms after previous surgical repair of coarctation.20–22 Stent graft therapy has some advantages over surgical treatment, such as granting less invasive access to the target lesion, resulting in shorter hospital stays, and minimal pain for the patient. Endovascular stent therapy may become the preferred option for this lesion in the near future. However, our study demonstrated excellent results for surgical treatment, suggesting that surgical therapy still remains a good option for the treatment of this lesion.
Bobylev et al.
The mean aortic clamp time was 53 13 minutes. This is considerably longer than the safety limit for aortic occlusion; therefore, six from seven patients were operated with CPB. Left heart bypass can provide sufficient perfusion of the circulation distal to the aortic cross-clamp and decrease the incident of postoperative paraplegia. Same authors used CPB with venous cannulation via the main pulmonary artery, below the pulmonary bifurcation, to prevent air embolism after air entry into the left atrium.23 In our experience, however, no complications after left heart circulation have been observed. In this study, more than half of the patients (29 of 50, 58%) had BAVs. In addition to the 16 isolated BAV patients, we observed a BAV in 9 of 16 patients with congenital AS, 2 of 4 patients with TGAs, and 3 of 7 patients with descending aortic aneurysms. Thoracic aortic disease in patients with BAVs is well documented,24,25 and molecular abnormality of the aortic wall of BAV has also been reported.26 Our results, even with the small number of patients, suggest that the presence of a BAV, including neo BAV combined with other CHDs, is also a long-term risk factor for aortic aneurysms. Careful long-term follow-up is mandatory for this cohort. On the contrary, 10 out of 44 patients with ascending aortic aneurysms were associated with CoA. In their recent study, Preventza et al reported coarctationassociated aortic aneurysms.27 Thoracic aortic aneurysms occurred in the descending aorta, in the ascending aorta, and in the left subclavian artery. They also reported multiple aneurysms and a high rate of association with BAV (45.4%). In our series, one patient was referred to us with the diagnosis of ascending and descending aortic aneurysms, who underwent coarctation repair at the age of 15 years. As for the association of coarctation and BAV, seven of the ten patients with ascending aortic aneurysms and coarctation had BAV, and three of the seven patients with descending aneurysm after CoA repair had BAV. This fact suggests a multiplier effect of CoA and BAV for the development of a thoracic aortic aneurysm. In conclusion, our results demonstrate that thoracic aortic aneurysms can develop in patients with various kinds of CHD. These predominantly developed in male patients, and are highly associated with BAV and aortic coarctation. In terms of surgical treatment, replacement with a composite graft is the standard procedure for ascending aortic aneurysms. A valve-sparing operation can be performed in selected patients with aortic root dilation after surgery for complex CHD and also in selected patients with BAVs. Graft replacement using a CPB is the standard procedure for descending aortic aneurysms. Midterm results were excellent for both ascending and descending aortic aneurysms.
Note This article was presented at the 42th annual meeting of the German Society for Thoracic and Cardiovascular Surgery in Freiburg, Germany, February 18, 2013.
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Surgical Treatment of Thoracic Aortic Aneurysms
Surgical Treatment of Thoracic Aortic Aneurysms
Bobylev et al.
Acknowledgments Parts of this paper (in the “Patients and Methods” and “Results” sections) are reprinted from Ono M, Goerler H, Boethig D, Westhoff-Bleck M, Breymann T. Current surgical management of ascending aortic aneurysm in children and young adults. Ann Thorac Surg 2009;88(5):1527-1533, with kind permission from Elsevier.
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