ORIGINAL ARTICLE – ADULT CARDIAC
Interactive CardioVascular and Thoracic Surgery 19 (2014) 584–589 doi:10.1093/icvts/ivu186 Advance Access publication 3 July 2014
Mid-term results of aortic root replacement using a self-assembled biological composite graft Katharina Meszarosa,b, Sophia Linigera, Martin Czernya, Olaf Stangera, David Reinekea, Lars Englbergera and Thierry P. Carrela,* a b
Department for Cardiovascular Surgery, University Hospital Berne, Berne, Switzerland Department for General Surgery, Medical University of Graz, Graz, Austria
* Corresponding author. Clinic for Cardiovascular Surgery, University Hospital Berne, 3010 Bern, Switzerland. Tel: +41-31-6322375; fax: +41-31-6324442; e-mail: [email protected] (T. Carrel). Received 17 February 2014; received in revised form 2 May 2014; accepted 5 May 2014
Abstract OBJECTIVES: To report the mid-term results of aortic root replacement using a self-assembled biological composite graft, consisting of a vascular tube graft and a stented tissue valve. METHODS: Between January 2005 and December 2011, 201 consecutive patients [median age 66 (interquartile range, IQR, 55–77) years, 31 female patients (15.4%), median logistic EuroSCORE 10 (IQR 6.8–23.2)] underwent aortic root replacement using a stented tissue valve for the following indications: annulo-aortic ectasia or ascending aortic aneurysm with aortic valve disease in 162 (76.8%) patients, active infective endocarditis in 18 (9.0%) and acute aortic dissection Stanford type A in 21 (10.4%). All patients underwent clinical and echocardiographic follow-up. We analysed survival and valve-related events. RESULTS: The overall in-hospital mortality rate was 4.5%. One- and 5-year cardiac-related mortality rates were 3 and 6%, and overall survival was 95 ± 1.5 and 75 ± 3.6%, respectively. The rate of freedom from structural valve failure was 99% and 97 ± 0.4% at the 1- and 5-year follow-up, respectively. The incidence rates of prosthetic valve endocarditis were 3 and 4%, respectively. During a median follow-up of 28 (IQR 14–51) months, only 2 (1%) patients required valve-related redo surgery due to prosthetic valvular endocarditis and none suffered from thromboembolic events. One percent of patients showed structural valve deterioration without any clinical symptoms; none of the patients suffered greater than mild aortic regurgitation. CONCLUSIONS: Aortic root replacement using a self-assembled biological composite graft is an interesting option. Haemodynamic results are excellent, with freedom from structured valve failure. Need for reoperation is extremely low, but long-term results are necessary to prove the durability of this concept. Keywords: Aortic root replacement • Biological valve • Echocardiography • Results
INTRODUCTION The ideal conduit for the surgical treatment of aortic root pathologies—in case the aortic valve cannot be preserved—remains to be defined. When the aortic valve must be replaced, there are several options: (i) a composite graft with a mechanical or a biological valve, (ii) an aortic homograft and (iii) a pulmonary autograft. Commercially available composite grafts have been historically constructed with a mechanical valve, but more recently there have been biological composite grafts available on the market. Some of them have shown controversial results in the mid- to long term [1–4]. Despite these advances, some authors reported excellent survival rates and a very low incidence of valve-related events in patients who received self-assembled composite grafts with either stentless or stented tissue valves. With such implants, there is some concern with regard to the exchange of a failed tissue valve that could mean a technically demanding re-root replacement [5, 6].
The aim of this report is to present our experience with aortic root replacement using a biological, self-assembled composite graft, consisting of a vascular tube graft and a stented tissue valve.
PATIENTS AND METHODS Patients Between January 2005 and December 2011, 201 consecutive patients underwent emergency and elective aortic root replacement using a self-assembled composite graft with a stented aortic valve for different aortic root pathologies. Preoperative patient characteristics and clinical conditions are summarized in Tables 1 and 2. Patients were stratified according to the EuroSCORE parameters [7]. Our institutional review board approved the study and waived the need for patient consent.
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
K. Meszaros et al. / Interactive CardioVascular and Thoracic Surgery
Table 3:
Postoperative patient characteristics
n (%) or median (IQR) Demographic data Age (years) Male Female Body mass index Body surface area Cardiovascular risk factors Diabetes Dyslipidaemia Arterial hypertension (RR systol. >140 mmHg) Current nicotine abuse Stopped nicotine abuse Coronary artery disease Preoperative health conditions Cerebrovascular insult preop. Severe neurological impairment Chronic obstructive pulmonary disease > GOLD 2 Creatinine >150 mmol/l Pulmonary hypertension (systol. >70 mmHg) Previous myocardial infarction Left ventricular ejection fraction preop. Additive EuroSCORE Logistic EuroSCORE Haemodynamic instability preop. Preoperative aortic and/or valvular pathology Aortic dissection Stanford type A Active infective endocarditis Annulo-aortic ectasia and/or aortic valve pathology Redo surgery
66.0 (55.0–77.0) 170 (84.6%) 31 (15.4%) 25.8 (23.6–28.6) 2.0 (1.8–2.1) 17 (8.5%) 86 (42.8%) 141 (70.1%) 31 (15.4%) 71 (35.3%) 65 (32.3%) 20 (10.0%) 10 (5%) 25 (12.4%) 6 (3.0%) 8 (4.0%) 11 (5.5%) 60.0 (54.0–65.0) 8.0 (6.0–10.0) 10.0 (6.8–23.2) 19 (9.5%) 21 (10.4%) 18 (9.0%) 162 (80.6%) 27 (13.4%)
RR: riva-rocci (for blood pressure).
Table 2: Intraoperative patient characteristics n (%) or median (IQR) Extracorporeal circulation time (min) Aortic cross-clamp time (min) Deep hypothermic circulatory arrest Mean duration of DHCA (min) Extent of aortic repair Elephant trunk Hemi-arch replacement Total arch replacement Concomitant procedure Coronary artery bypass grafting Mitral valve surgery (repair/replacement) CABG and others (incl. aortic) Mitral valve surgery and others Others Subaortic myectomy (Morrow)
125.5 (101.3–162.0) 95.0 (55.3–124.8) 120 (59.7%) 15.0 (11.0–22.0) 4 (2.0%) 68 (33.8%) 6 (3.0%) 93 (46.3%) 47 (23.4%) 8 (4.0%) 7 (3.5%) 13 (6.5%) 18 (9.0%) 4 (2.0%)
DHCA: deep hypothermic circulatory arrest; CABG: coronary artery bypass grafting.
Indications for aortic root replacement The indications for aortic root replacement were: annulo-aortic ectasia or ascending aortic aneurysm with concomitant aortic valve
n (%) or median (IQR) Superficial sternal wound infection Deep sternal wound infection Revision for bleeding Perioperative myocardial infarction Pacemaker implantation Postoperative renal failure requiring dialysis Intensive care unit stay (days) No transfusion required In-hospital mortality
3 (1.5%) 1 (0.5%) 11 (5.5%) 4 (2.0%) 8 (4.0%) 7 (3.5%) 1.0 (1.0–2.0) 33 (16.4%) 9 (4.5%)
pathology (regurgitation or stenosis) (n = 162), active infective endocarditis of the aortic valve in patients with enlarged aortic root (n = 18) or acute aortic dissection Stanford type A (n = 21). A significant proportion of the patients had concomitant cardiac pathologies such as coronary artery disease, mitral or tricuspid valve pathologies, persisting foramen ovale and others, and received combined surgery (Table 3). The use of a biological composite graft was the preferred option for patients older than 60–65 years and for those with a contraindication or high risk for oral anticoagulation and also in exceptional cases, the patient himself was against a mechanical valve and concomitant life-long oral anticoagulation.
Surgical technique The site of cannulation for extracorporeal circulation depends on the procedure. For elective isolated aortic root replacement, extracorporeal circulation is established via ascending aorta cannulation and venous drainage through a two-staged cannula inserted into the right atrium. For repair of acute aortic dissection and for redo procedures, arterial cannulation is always performed via the right subclavian artery, and only exceptionally through the femoral artery. All procedures are performed in mild hypothermia (core temperature between 28 and 32°C). If surgery extends to the aortic arch, hypothermic circulatory arrest is performed using bilateral antegrade cerebral perfusion. Myocardial protection is achieved with antegrade instillation of crystalloid and/or blood cardioplegic solution. Venting of the left heart cavities is performed through a catheter inserted in the right superior pulmonary vein. After resection of the aortic valve and excision of the coronary ostia, the diseased aortic wall is resected. Replacement of the aortic root is performed with a stented tissue valve (Perimount Magna and Magna Ease, Carpentier-Edwards, Irvine, CA, USA) fixed in a vascular prosthesis (Vascutek Valsalva Gelweave, Vascutek Terumo Corporation, Glasgow, UK) in all cases of this series. The valve is sutured with the vascular prosthesis using three single polypropylene sutures (Fig. 1). The self-made composite graft is then implanted in the modified Bentall technique [8]. The composite graft is fixed to the aortic annulus with 2-0 Ticron double-armed pledgeted sutures. The stitches are performed from outside of the aortic annulus. Then, the coronary buttons are re-inserted into the graft with running polypropylene 6-0 sutures. The distal anastomosis, depending on the extent of aortic repair, is performed whenever possible during aortic cross-clamping. When the distal anastomosis is performed at the level of the aortic arch, a separate
ORIGINAL ARTICLE
Table 1: Preoperative patient characteristics
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Table 4:
Follow-up data n (%) or median (IQR)
Clinical follow-up completed Lost to follow-up Follow-up period (months postoperatively) Overall mortality (including intrahospital) Mortality during follow-up Cardiac-related mortality (including intrahospital) Non-cardiac-related mortality (including intrahospital) Cause of death unknown Valve-related events Endocarditis Reoperation Thromboembolic events Haemorrhage Echocardiographic follow-up Mean aortic gradient (mmHg)
199 (99.4%) 2 (1.0%) 27.5 (13.8–51.0) 19 (9.5%) 10 (5.0%) 7 (3.5%) 8 (4.0%) 4 (2.1%) 5 (2.5%) 2 (1.0%) 0 (0%) 3 (1.5%) 157 10 (8–13)
Kaplan and Meier. All calculations were performed using IBM SPSS Statistics for Windows, Version 20.0 (IBM Corp., Armonk, NY, USA; Released 2011).
Figure 1: Self-assembled bio-composite graft using stented tissue valve (Perimount Magna/Magna Ease) and a vascular tube graft (Vascutek Gelweave).
RESULTS Postoperative results and in-hospital mortality
vascular graft with a side arm (Vascutek Anteflow Gelweave) is used. This allows one to perform the distal part of aortic repair as soon as the target temperature is obtained and therefore to rewarm the patient as soon as possible. After completion of the distal anastomosis, the graft is cannulated through the side branch, cross-clamped and cardiopulmonary bypass is restarted. Finally, end-to-end anastomosis between the two vascular prostheses is performed and the cross-clamp can be removed. Operative data are summarized in (Table 3), while postoperative data are presented in (Table 4).
Data collection and follow-up protocol Baseline, peri- and postoperative data were collected prospectively in our institutional Dendrite database. Patients were followed in our aortic outpatient clinic 6 months postoperatively and annually thereafter; all patients received echocardiographic follow-up 3 months postoperatively and annually thereafter. Reporting of valve-related events was performed according to the guidelines proposed by Akins et al. [9]. For follow-up, patients and their physician were contacted by phone call and interviewed. Clinical and echocardiographic data were collected in an Excel database.
Overall in-hospital mortality was 4.5%; 1 (0.5%) patient suffered a massive ischaemic cerebrovascular complication and another died from intracerebral bleeding during the postoperative period. One patient had recurrent prosthetic endocarditis and died because of therapy-refractory septic shock; another patient with prolonged ICU stay developed candida sepsis and subsequent multiorgan failure. Finally, 5 patients developed postoperative low cardiac output and died from multiorgan failure. The 6 patients with cardiac-related in-hospital mortality were all critically unstable before surgery and were all operated on under emergency conditions. The median logistic EuroSCORE of these patients was 65 (IQR 42.2–87.7). The re-exploration rate was 5.5% and the perioperative stroke rate (defined as any neurological disturbance and/or neurocognitive deficit) was 4%; 3.5% of patients developed acute postoperative renal failure requiring dialysis. One (0.4%) patient developed a deep sternal wound infection, which required sternectomy and a myocutaneous flap. A superficial wound infection requiring presternal vacuum-assisted closure and subsequent secondary suture occurred in 3 patients. Postoperative atrial fibrillation and/or flutter occurred in 28.9%, and 4.0% of patients required a transvenous pacemaker implantation postoperatively because of persisting bradycardic atrial fibrillation or total atrioventricular block.
Statistical analysis Continuous data, unless not otherwise indicated, are presented as a median and interquartile range (IQR). Discrete data are given as counts and percentages. Estimates for survival and incidence of valve-related events were calculated according to the method of
Follow-up The median follow-up was 27.5 (IQR 13.8–51.0) months, with a range from 0.5 to 84 months.
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Survival at follow-up
ORIGINAL ARTICLE
The overall mortality rate at follow-up was 9.5% (19 of 201 patients) (Fig. 2), while the mortality rate during follow-up was 4% (9 of 201). Two patients were lost to follow-up. One patient died of a sudden cardiac death of unknown cause during follow-up. The remaining 5 patients died from non-cardiac diseases such as neoplasm (n = 2), posttraumatic intracerebral bleeding (n = 1) and cerebrovascular insult (n = 2); in 4 cases, the cause of mortality was not available. One- and 5-year actuarial survival rates were 95 ± 1.5% and 75 ± 3.6%, respectively. One- and 5-year rates of freedom from cardiac-related mortality were 97 ± 1.2% and 94 ± 1.7%, respectively (Fig. 3). One- and 5-year rates of freedom from non-cardiac-related mortality were 98 ± 0.8% and 89 ± 2.4%, respectively.
Valve-related events One- and 5-year actuarial rates of freedom from structural valve failure were 99% and 97 ± 0.4%, respectively (Fig. 4). Two patients showed minimal structural valve deterioration on last follow-up echocardiography, but good left ventricular ejection fraction (74 and 59%, respectively) and low mean transvalvular gradients (12 and 11 mmHg, respectively). The incidence rate of prosthetic endocarditis was 1% at the 1-year follow-up and 3% at the 5-year follow-up, respectively. A total of 5 patients developed active infective endocarditis during follow-up. Two patients had to be reoperated; both suffered a prosthetic endocarditis with Staphylococcus aureus. Both were alive and in good condition at follow-up. Two other cases of prosthetic endocarditis could be successfully treated medically with appropriate antibiosis; none of the patients showed infective embolization or significant aortic regurgitation. One patient with recurrent endocarditis died during the in-hospital period from septic shock. One- and 5-year actuarial rates of freedom from reoperation were 99% and 98 ± 0.3%, respectively. Two patients had to be reoperated because of prosthetic endocarditis (see above). No reoperation had to be performed due to structural valve failure. One- and 5-year actuarial rates of freedom from haemorrhage were 99% and 96 ± 0.5%, respectively. Three patients exhibited a severe bleeding event during follow-up. One patient suffered a lower gastrointestinal bleeding, 1 patient had an intracerebral bleeding event and 1 patient reported recurrent epistaxis from the Kiesselbach’s plexus. These events occurred under salicylic acid 100 mg daily only. The rate of freedom from thromboembolic events was 100%.
Figure 2: Overall survival.
Figure 3: Cardiac-related mortality.
Echocardiographic follow-up Clinical follow-up The large majority of patients was in a good clinical condition at follow-up, 6.5% of patients suffered from dyspnoea NYHA Class III, 78.1% of patients had freedom from angina, 11% of patients reported angina Canadian Cardiovascular Society (CCS) I or II and none of the patients complained about dyspnoea or angina at rest. The most frequent medication was converting enzyme inhibitors inhibitors/sartans and beta-blockers; all patients were treated with platelet inhibitors and/or oral anticoagulation if indicated.
Of the total, 87.2% of patients had echocardiographic follow-up. None showed a higher than mild aortic regurgitation; the median transprosthetic gradient was 10 (8–13) mmHg. Twenty-nine patients presented with mild aortic regurgitation without haemodynamic significance; 14 cases were central aortic regurgitation (AR), 7 cases were described to be excentric (intravalvular in 4 and paravalvular in 3), while 1 patient exhibited a combination of a central and excentric regurgitation jet. In the remaining 7 cases, AR was not further specified.
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Figure 4: Freedom from structural valve failure.
DISCUSSION The aim of this report was to analyse the mid-term results in 200 patients who underwent aortic root replacement using selfassembled biological composite grafts. Owing to the demographic changes observed in the western society, there is an increasing trend towards a more widespread use of tissue valves in the last years [10]. Several surgical options are available to treat the diseased aortic root. If the use of a valve-sparing procedure is not possible because of diseased aortic cusps, the use of a mechanical valve conduit represented the gold standard for aortic root replacement over the past decades [8]. The implantation of a mechanical valve conduit requires life-long oral anticoagulation with the inherent risks of haemorrhage or thromboembolic complications. When implantation of a biological conduit is considered, these risks have to be outweighted against those of a redo procedure because of degeneration of the biological valve. The use of a pulmonary autograft is rarely recommended in older patients (more complex surgery requires a longer period of myocardial ischaemia and because of the limited availability of pulmonary homografts to reconstruct the right ventricular outflow tract [11]). So far, the use of commercially available or self-assembled composite grafts with a stented and stentless tissue valve inside has increased over the last years. The results of some of these biological valved conduits have been reported controversially, some being excellent, others leading to major problems [1–3]. Like others [12], we started to use our preferred stented tissue valve as part of a biological composite graft. We have had some experience with the BioValsalva Graft including the Elan® valve. We did not find any advantage of this conduit compared with the self-assembled composite graft. We prefer, in fact, to use the Perimount Magna or Magna Ease valve from Edwards, which has been known for excellent long-term results for many years. We do not find the biplex or triplex graft from Vascutek to be of major advantage. The original coated Vascutek Gelweave graft is the
preferred and most often used graft in our department (more than 250 thoracic and thoraco-abdominal aortic repairs yearly). In fact, one can reasonably ask what is the advantage of a selfassembled bio-composite graft? We found over years that the combination of one of the best biological valves on the market (that we use practically daily for isolated aortic valve replacement) with a very good aortic prosthetic graft is the best solution. Working with the Vascutek Gelweave is particularly convenient to reimplant the coronary arteries. Some authors are concerned that, in the case of structural valve failure, this procedure would require a complete root rereplacement with a higher procedural risk [4–6]. We found that complete root re-replacement is not necessary because the degenerated prosthesis can be cut out the graft and the new valve has to be sewn to both the annulus and the vascular graft. In contrast to other authors, we do not think that the assemblage of the composite graft on table leads to prolonged crossclamp and cardiopulmonary bypass times and therefore higher mortality and morbidity [4]. The three single sutures to fix the valve with the vascular graft require 1–2 min maximally. Even a running suture never requires more than 2–3 min [13]. The decision to use a stented tissue valve as prosthesis for a biological composite graft was based on our experience with this prosthesis that shows an excellent long-term haemodynamic performance and a very low incidence of patient–prosthesis mismatch [14]. Other authors reported good experience with the use of stentless tissue valves for assembling biological composite grafts. This approach may have some additional haemodynamic benefits; however, the fixation of the valve in the tube graft is more time-consuming (especially for the tabs at the top of the commissures) [15]. In terms of outcome, haemodynamic data during follow-up and freedom from structural valve failure, both solutions, seem to be comparable and both offer an excellent mid-term outcome [12, 13, 15]. Doubtless, the inclusion of all patients who underwent aortic root replacement with a self-assembled composite graft resulted in a higher in-hospital mortality in this series, since all emergency cases were also considered. All patients who died in the early postoperative period were high-risk patients undergoing emergency surgery or complex double- or triple-valve procedures. The outcome of elective aortic root replacement with this technique was excellent in the short term with a mortality rate near to 0%. Perioperative morbidity concerning stroke rate, acute renal failure requiring dialysis, rethoracotomy rate and others were comparable with other series [1, 3, 12, 13]. Mortality during followup was non-cardiac in the majority of patients. These results have to be considered carefully, because of the retrospective data acquisition by telephone interview of patients, their relatives and/or general practitioners. Comparable to other series, the occurrence of valve-related complications was rare. To avoid prosthetic valve endocarditis and/or recurrence of pre-existing native valve endocarditis, a strict adherence to endocarditis prophylaxis, as proposed by the ESC [16], was recommended in the discharge protocol. As expected and previously described by other authors, infection of the prosthetic valve with S. aureus almost always results in extensive tissue destruction, abscess formation and infective embolization, all requiring emergency valve re-replacement [17–19]. In the case of a native valve endocarditis or a postoperative endocarditis of the bio-composite graft, homografts and stentless bioroots like the Medtronic Freestyle® may represent interesting alternatives to the self-assembled bio-composite graft. All patients after aortic root replacement should be followed closely with repeated clinical examinations, echocardiograms and
computed tomography to detect changes that need more careful observation or potentially additional treatment. The described conduit showed promising results in the mid term; nevertheless, long-term results must be available to finally evaluate the durability of the conduit.
Limitations and strengths of this study This report implies all the limitations of a single-centre retrospective study. The strength of this study is that we report a series of consecutive patients and did not exclude subgroups at risk such as acute aortic dissection Stanford type A, active infective endocarditis with aortic root involvement, combined procedures and redo surgery. Therefore this series gives a clear picture of mid-term results also in highly challenging patients.
Funding The Clinic for Cardiovascular Surgery of the University Berne received research grants from Edwards Lifesciences, Irvine, CA. Conflict of interest: none declared.
REFERENCES [1] Ennker IA, Albert A, Dalladaku F, Rosendahl U, Ennker J, Florath I. Midterm outcome after aortic root replacement with stentless porcine bioprostheses. Eur J Cardiothorac Surg 2011;40:429–34. [2] Carrel TP, Schoenhoff FS, Schmidli J, Stalder M, Eckstein FS, Englberger L. Deleterious outcome of no-react-treated stentless valved conduits after aortic root replacement: why were warnings ignored? J Thorac Cardiovasc Surg 2008;136:52–7. [3] Dapunt OE, Easo J, Hoelzl PPF, Murin P, Suedkamp M, Horst M et al. Stentless full root bioprosthesis in surgery for complex aortic valveascending aortic disease: a single center experience of over 300 patients. Eur J Cardiothorac Surg 2008;33:554–9. [4] Moorjani N, Modi A, Mattam K, Barlow C, Tsang G, Haw M et al. Aortic root replacement using a Biovalsalva Prosthesis in comparison to a ‘Handsewn’ composite bioprosthesis. J Card Surg 2010;25:321–6. [5] Nowicki ER, Petterson GB, Smedira NG, Roselli EE, Blackstone EH, Lytle BW. Aortic allograft valve reoperation: surgical challenges and patient risks. Ann Thorac Surg 2008;86:761–8. [6] Kirsch EWM, Radu NC, Mekontso-Dessap A, Hillion ML, Loisance DD. Aortic root replacement after previous surgical intervention on the aortic valve, aortic root or ascending aorta. J Thorac Cardiovasc Surg 2006;131: 601–8. [7] Nashef SA, Roques F, Michel P, Gauducheau E, Lemeshow S, Salamon R. European system for cardiac operative risk evaluation (EuroSCORE). Eur J Cardiothorac Surg 1999;16:9–13. [8] Bentall H, De Bono A. A technique for complete replacement of the ascending aorta. Thorax 1968;23:338–9. [9] Akins CW, Miller DC, Turina MI, Kouchoukos NT, Blackstone EH, Grunkemeier GL et al. Guidelines for reporting mortality and morbidity after cardiac valve interventions. Ann Thorac Surg 2008;85:1490–5. [10] Brown JM, O’Brien SM, Wu C, Sikora JAH, Griffith BP, Gammie JS. Isolated aortic valve replacement in North America comprising 108,687 patients in 10 years. Changes in risks, valve types, and outcomes in the Society of Thoracic Surgeons National Database. J Thorac Cardiovasc Surg 2009;137: 82–90. [11] Oudinaud TM, Baron F, Raffoul R, Pagis B, Vergnat M, Parisot C et al. Redo aortic root surgery for failure of an aortic homograft is a major technical challenge. Eur J Cardiothorac Surg 2008;33:989–94. [12] Kirsch ME, Ooka T, Zannis K, Deux JF, Loisance DY. Bioprosthetic replacement of the ascending thoracic aorta. What are the options? Eur J Cardiothorac Surg 2009;35:77–82.
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[13] Urbanski PP, Heinz N, Zhan X, Hijazi H, Zacher M, Diegeler A. Modified bio-Bentall procedure: 10-year experience. Eur J Cardiothorac Surg 2010; 37:1317–21. [14] Wyss TR, Bigler M, Stalder M, Englberger L, Aymard T, Kadner A et al. Absence of prosthesis-patient mismatch with the new generation of Edwards stented aortic bioprosthesis. Interact CardioVasc Thorac Surg 2010;10:884–8. [15] Stewart AS, Takayama H, Smith CR. Modified Bentall operation with a novel biologic valved conduit. Ann Thorac Surg 2010;89:938–41. [16] Vahanian A, Alfieri O, Andreotti F, Antunes MJ, Barón-Esquivias G, Baumgartner H et al. Guidelines on the management of valvular heart disease (version 2012). Joint Task Force on the Management of Valvular Heart Disease of the European Society of Cardiology (ESC); European Association for Cardio-Thoracic Surgery (EACTS). Eur J Cardiothorac Surg 2012;42:S1–44. [17] Meszaros K, Nujic S, Sodeck GH, Englberger L, Koenig T, Schoenhoff F et al. Long-term results after operations for active infective endocarditis in native and prosthetic valves. Ann Thorac Surg 2012;94:1204–10. [18] Hung HC, Chen SC, Chan KC, Tsui TL, Tsao SM, Leel YT et al. Retrospective evaluation of infective endocarditis over ten years in Taiwan. J Heart Valve Dis 2013;222:248–56. [19] Kim TS, Na CY, Oh SS, Kim JH. Long-term mortality and morbidity after button Bentall operation. J Card Surg 2013;28:280–4.
eComment. Custom-made tissue valve composite tube graft for complex aortic root disease: a safe operative technique Author: Christos Tourmousoglou University of Ioannina, Medical School, Ioannina, Greece doi: 10.1093/icvts/ivu300 © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. I read with great interest the paper by Meszaros et al. who evaluated the mid-term results of aortic root replacement using a self-assembled biological composite graft. The authors found that the haemodynamic results were excellent, with freedom from structural valve failure. The need for reoperation was extremely low, but longterm results were necessary to prove the durability of this concept [1]. I would like to add some thoughts to this very interesting alternative: "the custom-tailored valved conduit for aortic root disease". The existence of extensive destruction of the aortoventricular junction from previous complex operations such as aortic valve replacements or prosthetic valve endocarditis is a real challenge for the surgeon. Dr David has a tremendous experience with the reconstruction of the left ventricular outflow tract with a tailored tubular Dacron graft and his technique deserves special consideration. There are key points that need special attention when a surgeon performs this complex operation. The surgeon has to use a tubular Dacron graft that is 3 to 6 mm larger than the diameter of the left ventricular outflow tract (LVOT) or large enough to permit the implantation of a prosthetic aortic valve. If there is any defect in the LVOT because of its pathology, then one of the end of the Dacron graft is tailored to correct this defect and this end of the graft is sutured directly to the interventricular septum and intervalvular fibrous body with continuous sutures. Next, interrupted sutures are needed at the medial and lateral fibrous trigones. Then the coronary arteries are reimplanted into the graft before or after the prosthetic aortic valve is implanted. The size of the valve that is implanted has to be 5 mm smaller than the graft as the sizes of most artificial valves are not metric [2]. Another very important issue is the position of implantation of the valve inside the graft. If stented valves are used, pericardial or porcine, they could be placed inside the Dacron graft a few millimeters above the anastomosis between the Dacron and the aortic annulus. In this way, it is easier for the surgeon to perform a future re-replacement of the bioprosthesis without taking down the coronary arteries from the Dacron graft [3]. A tailored graft for replacement of the aortic root and reconstruction of the LVOT is a safe and useful surgical option. Conflict of interest: none declared. References [1] Meszaros K, Liniger S, Czerny M, Stanger O, Reineke D, Englberger L et al. Midterm results of aortic root replacement using a self-assembled biological composite graft. Interact CardioVasc Thorac Surg 2014;19:584–9. [2] Krasopoulos G, David T, Armstrong S. Custom-tailored valved conduit for complex aortic root disease. J Thorac Cardiovasc Surg 2008;135:3–7. [3] David T. Surgery of the aortic valve. Curr Probl Surg 1999:36:423–501.
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K. Meszaros et al. / Interactive CardioVascular and Thoracic Surgery
Interactive CardioVascular and Thoracic Surgery 19 (2014) 584–589 doi:10.1093/icvts/ivu186 Advance Access publication 3 July 2014
Mid-term results of aortic root replacement using a self-assembled biological composite graft Katharina Meszarosa,b, Sophia Linigera, Martin Czernya, Olaf Stangera, David Reinekea, Lars Englbergera and Thierry P. Carrela,* a b
Department for Cardiovascular Surgery, University Hospital Berne, Berne, Switzerland Department for General Surgery, Medical University of Graz, Graz, Austria
* Corresponding author. Clinic for Cardiovascular Surgery, University Hospital Berne, 3010 Bern, Switzerland. Tel: +41-31-6322375; fax: +41-31-6324442; e-mail: [email protected] (T. Carrel). Received 17 February 2014; received in revised form 2 May 2014; accepted 5 May 2014
Abstract OBJECTIVES: To report the mid-term results of aortic root replacement using a self-assembled biological composite graft, consisting of a vascular tube graft and a stented tissue valve. METHODS: Between January 2005 and December 2011, 201 consecutive patients [median age 66 (interquartile range, IQR, 55–77) years, 31 female patients (15.4%), median logistic EuroSCORE 10 (IQR 6.8–23.2)] underwent aortic root replacement using a stented tissue valve for the following indications: annulo-aortic ectasia or ascending aortic aneurysm with aortic valve disease in 162 (76.8%) patients, active infective endocarditis in 18 (9.0%) and acute aortic dissection Stanford type A in 21 (10.4%). All patients underwent clinical and echocardiographic follow-up. We analysed survival and valve-related events. RESULTS: The overall in-hospital mortality rate was 4.5%. One- and 5-year cardiac-related mortality rates were 3 and 6%, and overall survival was 95 ± 1.5 and 75 ± 3.6%, respectively. The rate of freedom from structural valve failure was 99% and 97 ± 0.4% at the 1- and 5-year follow-up, respectively. The incidence rates of prosthetic valve endocarditis were 3 and 4%, respectively. During a median follow-up of 28 (IQR 14–51) months, only 2 (1%) patients required valve-related redo surgery due to prosthetic valvular endocarditis and none suffered from thromboembolic events. One percent of patients showed structural valve deterioration without any clinical symptoms; none of the patients suffered greater than mild aortic regurgitation. CONCLUSIONS: Aortic root replacement using a self-assembled biological composite graft is an interesting option. Haemodynamic results are excellent, with freedom from structured valve failure. Need for reoperation is extremely low, but long-term results are necessary to prove the durability of this concept. Keywords: Aortic root replacement • Biological valve • Echocardiography • Results
INTRODUCTION The ideal conduit for the surgical treatment of aortic root pathologies—in case the aortic valve cannot be preserved—remains to be defined. When the aortic valve must be replaced, there are several options: (i) a composite graft with a mechanical or a biological valve, (ii) an aortic homograft and (iii) a pulmonary autograft. Commercially available composite grafts have been historically constructed with a mechanical valve, but more recently there have been biological composite grafts available on the market. Some of them have shown controversial results in the mid- to long term [1–4]. Despite these advances, some authors reported excellent survival rates and a very low incidence of valve-related events in patients who received self-assembled composite grafts with either stentless or stented tissue valves. With such implants, there is some concern with regard to the exchange of a failed tissue valve that could mean a technically demanding re-root replacement [5, 6].
The aim of this report is to present our experience with aortic root replacement using a biological, self-assembled composite graft, consisting of a vascular tube graft and a stented tissue valve.
PATIENTS AND METHODS Patients Between January 2005 and December 2011, 201 consecutive patients underwent emergency and elective aortic root replacement using a self-assembled composite graft with a stented aortic valve for different aortic root pathologies. Preoperative patient characteristics and clinical conditions are summarized in Tables 1 and 2. Patients were stratified according to the EuroSCORE parameters [7]. Our institutional review board approved the study and waived the need for patient consent.
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
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Table 3:
Postoperative patient characteristics
n (%) or median (IQR) Demographic data Age (years) Male Female Body mass index Body surface area Cardiovascular risk factors Diabetes Dyslipidaemia Arterial hypertension (RR systol. >140 mmHg) Current nicotine abuse Stopped nicotine abuse Coronary artery disease Preoperative health conditions Cerebrovascular insult preop. Severe neurological impairment Chronic obstructive pulmonary disease > GOLD 2 Creatinine >150 mmol/l Pulmonary hypertension (systol. >70 mmHg) Previous myocardial infarction Left ventricular ejection fraction preop. Additive EuroSCORE Logistic EuroSCORE Haemodynamic instability preop. Preoperative aortic and/or valvular pathology Aortic dissection Stanford type A Active infective endocarditis Annulo-aortic ectasia and/or aortic valve pathology Redo surgery
66.0 (55.0–77.0) 170 (84.6%) 31 (15.4%) 25.8 (23.6–28.6) 2.0 (1.8–2.1) 17 (8.5%) 86 (42.8%) 141 (70.1%) 31 (15.4%) 71 (35.3%) 65 (32.3%) 20 (10.0%) 10 (5%) 25 (12.4%) 6 (3.0%) 8 (4.0%) 11 (5.5%) 60.0 (54.0–65.0) 8.0 (6.0–10.0) 10.0 (6.8–23.2) 19 (9.5%) 21 (10.4%) 18 (9.0%) 162 (80.6%) 27 (13.4%)
RR: riva-rocci (for blood pressure).
Table 2: Intraoperative patient characteristics n (%) or median (IQR) Extracorporeal circulation time (min) Aortic cross-clamp time (min) Deep hypothermic circulatory arrest Mean duration of DHCA (min) Extent of aortic repair Elephant trunk Hemi-arch replacement Total arch replacement Concomitant procedure Coronary artery bypass grafting Mitral valve surgery (repair/replacement) CABG and others (incl. aortic) Mitral valve surgery and others Others Subaortic myectomy (Morrow)
125.5 (101.3–162.0) 95.0 (55.3–124.8) 120 (59.7%) 15.0 (11.0–22.0) 4 (2.0%) 68 (33.8%) 6 (3.0%) 93 (46.3%) 47 (23.4%) 8 (4.0%) 7 (3.5%) 13 (6.5%) 18 (9.0%) 4 (2.0%)
DHCA: deep hypothermic circulatory arrest; CABG: coronary artery bypass grafting.
Indications for aortic root replacement The indications for aortic root replacement were: annulo-aortic ectasia or ascending aortic aneurysm with concomitant aortic valve
n (%) or median (IQR) Superficial sternal wound infection Deep sternal wound infection Revision for bleeding Perioperative myocardial infarction Pacemaker implantation Postoperative renal failure requiring dialysis Intensive care unit stay (days) No transfusion required In-hospital mortality
3 (1.5%) 1 (0.5%) 11 (5.5%) 4 (2.0%) 8 (4.0%) 7 (3.5%) 1.0 (1.0–2.0) 33 (16.4%) 9 (4.5%)
pathology (regurgitation or stenosis) (n = 162), active infective endocarditis of the aortic valve in patients with enlarged aortic root (n = 18) or acute aortic dissection Stanford type A (n = 21). A significant proportion of the patients had concomitant cardiac pathologies such as coronary artery disease, mitral or tricuspid valve pathologies, persisting foramen ovale and others, and received combined surgery (Table 3). The use of a biological composite graft was the preferred option for patients older than 60–65 years and for those with a contraindication or high risk for oral anticoagulation and also in exceptional cases, the patient himself was against a mechanical valve and concomitant life-long oral anticoagulation.
Surgical technique The site of cannulation for extracorporeal circulation depends on the procedure. For elective isolated aortic root replacement, extracorporeal circulation is established via ascending aorta cannulation and venous drainage through a two-staged cannula inserted into the right atrium. For repair of acute aortic dissection and for redo procedures, arterial cannulation is always performed via the right subclavian artery, and only exceptionally through the femoral artery. All procedures are performed in mild hypothermia (core temperature between 28 and 32°C). If surgery extends to the aortic arch, hypothermic circulatory arrest is performed using bilateral antegrade cerebral perfusion. Myocardial protection is achieved with antegrade instillation of crystalloid and/or blood cardioplegic solution. Venting of the left heart cavities is performed through a catheter inserted in the right superior pulmonary vein. After resection of the aortic valve and excision of the coronary ostia, the diseased aortic wall is resected. Replacement of the aortic root is performed with a stented tissue valve (Perimount Magna and Magna Ease, Carpentier-Edwards, Irvine, CA, USA) fixed in a vascular prosthesis (Vascutek Valsalva Gelweave, Vascutek Terumo Corporation, Glasgow, UK) in all cases of this series. The valve is sutured with the vascular prosthesis using three single polypropylene sutures (Fig. 1). The self-made composite graft is then implanted in the modified Bentall technique [8]. The composite graft is fixed to the aortic annulus with 2-0 Ticron double-armed pledgeted sutures. The stitches are performed from outside of the aortic annulus. Then, the coronary buttons are re-inserted into the graft with running polypropylene 6-0 sutures. The distal anastomosis, depending on the extent of aortic repair, is performed whenever possible during aortic cross-clamping. When the distal anastomosis is performed at the level of the aortic arch, a separate
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Table 1: Preoperative patient characteristics
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Table 4:
Follow-up data n (%) or median (IQR)
Clinical follow-up completed Lost to follow-up Follow-up period (months postoperatively) Overall mortality (including intrahospital) Mortality during follow-up Cardiac-related mortality (including intrahospital) Non-cardiac-related mortality (including intrahospital) Cause of death unknown Valve-related events Endocarditis Reoperation Thromboembolic events Haemorrhage Echocardiographic follow-up Mean aortic gradient (mmHg)
199 (99.4%) 2 (1.0%) 27.5 (13.8–51.0) 19 (9.5%) 10 (5.0%) 7 (3.5%) 8 (4.0%) 4 (2.1%) 5 (2.5%) 2 (1.0%) 0 (0%) 3 (1.5%) 157 10 (8–13)
Kaplan and Meier. All calculations were performed using IBM SPSS Statistics for Windows, Version 20.0 (IBM Corp., Armonk, NY, USA; Released 2011).
Figure 1: Self-assembled bio-composite graft using stented tissue valve (Perimount Magna/Magna Ease) and a vascular tube graft (Vascutek Gelweave).
RESULTS Postoperative results and in-hospital mortality
vascular graft with a side arm (Vascutek Anteflow Gelweave) is used. This allows one to perform the distal part of aortic repair as soon as the target temperature is obtained and therefore to rewarm the patient as soon as possible. After completion of the distal anastomosis, the graft is cannulated through the side branch, cross-clamped and cardiopulmonary bypass is restarted. Finally, end-to-end anastomosis between the two vascular prostheses is performed and the cross-clamp can be removed. Operative data are summarized in (Table 3), while postoperative data are presented in (Table 4).
Data collection and follow-up protocol Baseline, peri- and postoperative data were collected prospectively in our institutional Dendrite database. Patients were followed in our aortic outpatient clinic 6 months postoperatively and annually thereafter; all patients received echocardiographic follow-up 3 months postoperatively and annually thereafter. Reporting of valve-related events was performed according to the guidelines proposed by Akins et al. [9]. For follow-up, patients and their physician were contacted by phone call and interviewed. Clinical and echocardiographic data were collected in an Excel database.
Overall in-hospital mortality was 4.5%; 1 (0.5%) patient suffered a massive ischaemic cerebrovascular complication and another died from intracerebral bleeding during the postoperative period. One patient had recurrent prosthetic endocarditis and died because of therapy-refractory septic shock; another patient with prolonged ICU stay developed candida sepsis and subsequent multiorgan failure. Finally, 5 patients developed postoperative low cardiac output and died from multiorgan failure. The 6 patients with cardiac-related in-hospital mortality were all critically unstable before surgery and were all operated on under emergency conditions. The median logistic EuroSCORE of these patients was 65 (IQR 42.2–87.7). The re-exploration rate was 5.5% and the perioperative stroke rate (defined as any neurological disturbance and/or neurocognitive deficit) was 4%; 3.5% of patients developed acute postoperative renal failure requiring dialysis. One (0.4%) patient developed a deep sternal wound infection, which required sternectomy and a myocutaneous flap. A superficial wound infection requiring presternal vacuum-assisted closure and subsequent secondary suture occurred in 3 patients. Postoperative atrial fibrillation and/or flutter occurred in 28.9%, and 4.0% of patients required a transvenous pacemaker implantation postoperatively because of persisting bradycardic atrial fibrillation or total atrioventricular block.
Statistical analysis Continuous data, unless not otherwise indicated, are presented as a median and interquartile range (IQR). Discrete data are given as counts and percentages. Estimates for survival and incidence of valve-related events were calculated according to the method of
Follow-up The median follow-up was 27.5 (IQR 13.8–51.0) months, with a range from 0.5 to 84 months.
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Survival at follow-up
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The overall mortality rate at follow-up was 9.5% (19 of 201 patients) (Fig. 2), while the mortality rate during follow-up was 4% (9 of 201). Two patients were lost to follow-up. One patient died of a sudden cardiac death of unknown cause during follow-up. The remaining 5 patients died from non-cardiac diseases such as neoplasm (n = 2), posttraumatic intracerebral bleeding (n = 1) and cerebrovascular insult (n = 2); in 4 cases, the cause of mortality was not available. One- and 5-year actuarial survival rates were 95 ± 1.5% and 75 ± 3.6%, respectively. One- and 5-year rates of freedom from cardiac-related mortality were 97 ± 1.2% and 94 ± 1.7%, respectively (Fig. 3). One- and 5-year rates of freedom from non-cardiac-related mortality were 98 ± 0.8% and 89 ± 2.4%, respectively.
Valve-related events One- and 5-year actuarial rates of freedom from structural valve failure were 99% and 97 ± 0.4%, respectively (Fig. 4). Two patients showed minimal structural valve deterioration on last follow-up echocardiography, but good left ventricular ejection fraction (74 and 59%, respectively) and low mean transvalvular gradients (12 and 11 mmHg, respectively). The incidence rate of prosthetic endocarditis was 1% at the 1-year follow-up and 3% at the 5-year follow-up, respectively. A total of 5 patients developed active infective endocarditis during follow-up. Two patients had to be reoperated; both suffered a prosthetic endocarditis with Staphylococcus aureus. Both were alive and in good condition at follow-up. Two other cases of prosthetic endocarditis could be successfully treated medically with appropriate antibiosis; none of the patients showed infective embolization or significant aortic regurgitation. One patient with recurrent endocarditis died during the in-hospital period from septic shock. One- and 5-year actuarial rates of freedom from reoperation were 99% and 98 ± 0.3%, respectively. Two patients had to be reoperated because of prosthetic endocarditis (see above). No reoperation had to be performed due to structural valve failure. One- and 5-year actuarial rates of freedom from haemorrhage were 99% and 96 ± 0.5%, respectively. Three patients exhibited a severe bleeding event during follow-up. One patient suffered a lower gastrointestinal bleeding, 1 patient had an intracerebral bleeding event and 1 patient reported recurrent epistaxis from the Kiesselbach’s plexus. These events occurred under salicylic acid 100 mg daily only. The rate of freedom from thromboembolic events was 100%.
Figure 2: Overall survival.
Figure 3: Cardiac-related mortality.
Echocardiographic follow-up Clinical follow-up The large majority of patients was in a good clinical condition at follow-up, 6.5% of patients suffered from dyspnoea NYHA Class III, 78.1% of patients had freedom from angina, 11% of patients reported angina Canadian Cardiovascular Society (CCS) I or II and none of the patients complained about dyspnoea or angina at rest. The most frequent medication was converting enzyme inhibitors inhibitors/sartans and beta-blockers; all patients were treated with platelet inhibitors and/or oral anticoagulation if indicated.
Of the total, 87.2% of patients had echocardiographic follow-up. None showed a higher than mild aortic regurgitation; the median transprosthetic gradient was 10 (8–13) mmHg. Twenty-nine patients presented with mild aortic regurgitation without haemodynamic significance; 14 cases were central aortic regurgitation (AR), 7 cases were described to be excentric (intravalvular in 4 and paravalvular in 3), while 1 patient exhibited a combination of a central and excentric regurgitation jet. In the remaining 7 cases, AR was not further specified.
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Figure 4: Freedom from structural valve failure.
DISCUSSION The aim of this report was to analyse the mid-term results in 200 patients who underwent aortic root replacement using selfassembled biological composite grafts. Owing to the demographic changes observed in the western society, there is an increasing trend towards a more widespread use of tissue valves in the last years [10]. Several surgical options are available to treat the diseased aortic root. If the use of a valve-sparing procedure is not possible because of diseased aortic cusps, the use of a mechanical valve conduit represented the gold standard for aortic root replacement over the past decades [8]. The implantation of a mechanical valve conduit requires life-long oral anticoagulation with the inherent risks of haemorrhage or thromboembolic complications. When implantation of a biological conduit is considered, these risks have to be outweighted against those of a redo procedure because of degeneration of the biological valve. The use of a pulmonary autograft is rarely recommended in older patients (more complex surgery requires a longer period of myocardial ischaemia and because of the limited availability of pulmonary homografts to reconstruct the right ventricular outflow tract [11]). So far, the use of commercially available or self-assembled composite grafts with a stented and stentless tissue valve inside has increased over the last years. The results of some of these biological valved conduits have been reported controversially, some being excellent, others leading to major problems [1–3]. Like others [12], we started to use our preferred stented tissue valve as part of a biological composite graft. We have had some experience with the BioValsalva Graft including the Elan® valve. We did not find any advantage of this conduit compared with the self-assembled composite graft. We prefer, in fact, to use the Perimount Magna or Magna Ease valve from Edwards, which has been known for excellent long-term results for many years. We do not find the biplex or triplex graft from Vascutek to be of major advantage. The original coated Vascutek Gelweave graft is the
preferred and most often used graft in our department (more than 250 thoracic and thoraco-abdominal aortic repairs yearly). In fact, one can reasonably ask what is the advantage of a selfassembled bio-composite graft? We found over years that the combination of one of the best biological valves on the market (that we use practically daily for isolated aortic valve replacement) with a very good aortic prosthetic graft is the best solution. Working with the Vascutek Gelweave is particularly convenient to reimplant the coronary arteries. Some authors are concerned that, in the case of structural valve failure, this procedure would require a complete root rereplacement with a higher procedural risk [4–6]. We found that complete root re-replacement is not necessary because the degenerated prosthesis can be cut out the graft and the new valve has to be sewn to both the annulus and the vascular graft. In contrast to other authors, we do not think that the assemblage of the composite graft on table leads to prolonged crossclamp and cardiopulmonary bypass times and therefore higher mortality and morbidity [4]. The three single sutures to fix the valve with the vascular graft require 1–2 min maximally. Even a running suture never requires more than 2–3 min [13]. The decision to use a stented tissue valve as prosthesis for a biological composite graft was based on our experience with this prosthesis that shows an excellent long-term haemodynamic performance and a very low incidence of patient–prosthesis mismatch [14]. Other authors reported good experience with the use of stentless tissue valves for assembling biological composite grafts. This approach may have some additional haemodynamic benefits; however, the fixation of the valve in the tube graft is more time-consuming (especially for the tabs at the top of the commissures) [15]. In terms of outcome, haemodynamic data during follow-up and freedom from structural valve failure, both solutions, seem to be comparable and both offer an excellent mid-term outcome [12, 13, 15]. Doubtless, the inclusion of all patients who underwent aortic root replacement with a self-assembled composite graft resulted in a higher in-hospital mortality in this series, since all emergency cases were also considered. All patients who died in the early postoperative period were high-risk patients undergoing emergency surgery or complex double- or triple-valve procedures. The outcome of elective aortic root replacement with this technique was excellent in the short term with a mortality rate near to 0%. Perioperative morbidity concerning stroke rate, acute renal failure requiring dialysis, rethoracotomy rate and others were comparable with other series [1, 3, 12, 13]. Mortality during followup was non-cardiac in the majority of patients. These results have to be considered carefully, because of the retrospective data acquisition by telephone interview of patients, their relatives and/or general practitioners. Comparable to other series, the occurrence of valve-related complications was rare. To avoid prosthetic valve endocarditis and/or recurrence of pre-existing native valve endocarditis, a strict adherence to endocarditis prophylaxis, as proposed by the ESC [16], was recommended in the discharge protocol. As expected and previously described by other authors, infection of the prosthetic valve with S. aureus almost always results in extensive tissue destruction, abscess formation and infective embolization, all requiring emergency valve re-replacement [17–19]. In the case of a native valve endocarditis or a postoperative endocarditis of the bio-composite graft, homografts and stentless bioroots like the Medtronic Freestyle® may represent interesting alternatives to the self-assembled bio-composite graft. All patients after aortic root replacement should be followed closely with repeated clinical examinations, echocardiograms and
computed tomography to detect changes that need more careful observation or potentially additional treatment. The described conduit showed promising results in the mid term; nevertheless, long-term results must be available to finally evaluate the durability of the conduit.
Limitations and strengths of this study This report implies all the limitations of a single-centre retrospective study. The strength of this study is that we report a series of consecutive patients and did not exclude subgroups at risk such as acute aortic dissection Stanford type A, active infective endocarditis with aortic root involvement, combined procedures and redo surgery. Therefore this series gives a clear picture of mid-term results also in highly challenging patients.
Funding The Clinic for Cardiovascular Surgery of the University Berne received research grants from Edwards Lifesciences, Irvine, CA. Conflict of interest: none declared.
REFERENCES [1] Ennker IA, Albert A, Dalladaku F, Rosendahl U, Ennker J, Florath I. Midterm outcome after aortic root replacement with stentless porcine bioprostheses. Eur J Cardiothorac Surg 2011;40:429–34. [2] Carrel TP, Schoenhoff FS, Schmidli J, Stalder M, Eckstein FS, Englberger L. Deleterious outcome of no-react-treated stentless valved conduits after aortic root replacement: why were warnings ignored? J Thorac Cardiovasc Surg 2008;136:52–7. [3] Dapunt OE, Easo J, Hoelzl PPF, Murin P, Suedkamp M, Horst M et al. Stentless full root bioprosthesis in surgery for complex aortic valveascending aortic disease: a single center experience of over 300 patients. Eur J Cardiothorac Surg 2008;33:554–9. [4] Moorjani N, Modi A, Mattam K, Barlow C, Tsang G, Haw M et al. Aortic root replacement using a Biovalsalva Prosthesis in comparison to a ‘Handsewn’ composite bioprosthesis. J Card Surg 2010;25:321–6. [5] Nowicki ER, Petterson GB, Smedira NG, Roselli EE, Blackstone EH, Lytle BW. Aortic allograft valve reoperation: surgical challenges and patient risks. Ann Thorac Surg 2008;86:761–8. [6] Kirsch EWM, Radu NC, Mekontso-Dessap A, Hillion ML, Loisance DD. Aortic root replacement after previous surgical intervention on the aortic valve, aortic root or ascending aorta. J Thorac Cardiovasc Surg 2006;131: 601–8. [7] Nashef SA, Roques F, Michel P, Gauducheau E, Lemeshow S, Salamon R. European system for cardiac operative risk evaluation (EuroSCORE). Eur J Cardiothorac Surg 1999;16:9–13. [8] Bentall H, De Bono A. A technique for complete replacement of the ascending aorta. Thorax 1968;23:338–9. [9] Akins CW, Miller DC, Turina MI, Kouchoukos NT, Blackstone EH, Grunkemeier GL et al. Guidelines for reporting mortality and morbidity after cardiac valve interventions. Ann Thorac Surg 2008;85:1490–5. [10] Brown JM, O’Brien SM, Wu C, Sikora JAH, Griffith BP, Gammie JS. Isolated aortic valve replacement in North America comprising 108,687 patients in 10 years. Changes in risks, valve types, and outcomes in the Society of Thoracic Surgeons National Database. J Thorac Cardiovasc Surg 2009;137: 82–90. [11] Oudinaud TM, Baron F, Raffoul R, Pagis B, Vergnat M, Parisot C et al. Redo aortic root surgery for failure of an aortic homograft is a major technical challenge. Eur J Cardiothorac Surg 2008;33:989–94. [12] Kirsch ME, Ooka T, Zannis K, Deux JF, Loisance DY. Bioprosthetic replacement of the ascending thoracic aorta. What are the options? Eur J Cardiothorac Surg 2009;35:77–82.
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[13] Urbanski PP, Heinz N, Zhan X, Hijazi H, Zacher M, Diegeler A. Modified bio-Bentall procedure: 10-year experience. Eur J Cardiothorac Surg 2010; 37:1317–21. [14] Wyss TR, Bigler M, Stalder M, Englberger L, Aymard T, Kadner A et al. Absence of prosthesis-patient mismatch with the new generation of Edwards stented aortic bioprosthesis. Interact CardioVasc Thorac Surg 2010;10:884–8. [15] Stewart AS, Takayama H, Smith CR. Modified Bentall operation with a novel biologic valved conduit. Ann Thorac Surg 2010;89:938–41. [16] Vahanian A, Alfieri O, Andreotti F, Antunes MJ, Barón-Esquivias G, Baumgartner H et al. Guidelines on the management of valvular heart disease (version 2012). Joint Task Force on the Management of Valvular Heart Disease of the European Society of Cardiology (ESC); European Association for Cardio-Thoracic Surgery (EACTS). Eur J Cardiothorac Surg 2012;42:S1–44. [17] Meszaros K, Nujic S, Sodeck GH, Englberger L, Koenig T, Schoenhoff F et al. Long-term results after operations for active infective endocarditis in native and prosthetic valves. Ann Thorac Surg 2012;94:1204–10. [18] Hung HC, Chen SC, Chan KC, Tsui TL, Tsao SM, Leel YT et al. Retrospective evaluation of infective endocarditis over ten years in Taiwan. J Heart Valve Dis 2013;222:248–56. [19] Kim TS, Na CY, Oh SS, Kim JH. Long-term mortality and morbidity after button Bentall operation. J Card Surg 2013;28:280–4.
eComment. Custom-made tissue valve composite tube graft for complex aortic root disease: a safe operative technique Author: Christos Tourmousoglou University of Ioannina, Medical School, Ioannina, Greece doi: 10.1093/icvts/ivu300 © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. I read with great interest the paper by Meszaros et al. who evaluated the mid-term results of aortic root replacement using a self-assembled biological composite graft. The authors found that the haemodynamic results were excellent, with freedom from structural valve failure. The need for reoperation was extremely low, but longterm results were necessary to prove the durability of this concept [1]. I would like to add some thoughts to this very interesting alternative: "the custom-tailored valved conduit for aortic root disease". The existence of extensive destruction of the aortoventricular junction from previous complex operations such as aortic valve replacements or prosthetic valve endocarditis is a real challenge for the surgeon. Dr David has a tremendous experience with the reconstruction of the left ventricular outflow tract with a tailored tubular Dacron graft and his technique deserves special consideration. There are key points that need special attention when a surgeon performs this complex operation. The surgeon has to use a tubular Dacron graft that is 3 to 6 mm larger than the diameter of the left ventricular outflow tract (LVOT) or large enough to permit the implantation of a prosthetic aortic valve. If there is any defect in the LVOT because of its pathology, then one of the end of the Dacron graft is tailored to correct this defect and this end of the graft is sutured directly to the interventricular septum and intervalvular fibrous body with continuous sutures. Next, interrupted sutures are needed at the medial and lateral fibrous trigones. Then the coronary arteries are reimplanted into the graft before or after the prosthetic aortic valve is implanted. The size of the valve that is implanted has to be 5 mm smaller than the graft as the sizes of most artificial valves are not metric [2]. Another very important issue is the position of implantation of the valve inside the graft. If stented valves are used, pericardial or porcine, they could be placed inside the Dacron graft a few millimeters above the anastomosis between the Dacron and the aortic annulus. In this way, it is easier for the surgeon to perform a future re-replacement of the bioprosthesis without taking down the coronary arteries from the Dacron graft [3]. A tailored graft for replacement of the aortic root and reconstruction of the LVOT is a safe and useful surgical option. Conflict of interest: none declared. References [1] Meszaros K, Liniger S, Czerny M, Stanger O, Reineke D, Englberger L et al. Midterm results of aortic root replacement using a self-assembled biological composite graft. Interact CardioVasc Thorac Surg 2014;19:584–9. [2] Krasopoulos G, David T, Armstrong S. Custom-tailored valved conduit for complex aortic root disease. J Thorac Cardiovasc Surg 2008;135:3–7. [3] David T. Surgery of the aortic valve. Curr Probl Surg 1999:36:423–501.
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