Heart & Lung 44 (2015) 453e457
Contents lists available at ScienceDirect
Heart & Lung journal homepage: www.heartandlung.org
Pulmonary artery dissection in a patient with undiagnosed pulmonary hypertension e A case report and review of literature Carl Johan Malm, MD a, Lisa Ternström, MD a, Kirsten Jörgensen, MD, PhD b, Göran Dellgren, MD, PhD a, * a b
Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden Department of Cardiothoracic Anesthesia, Sahlgrenska University Hospital, Gothenburg, Sweden
a r t i c l e i n f o
a b s t r a c t
Article history: Received 1 April 2015 Received in revised form 7 June 2015 Accepted 9 June 2015 Available online 4 July 2015
Pulmonary artery dissection is rare and highly lethal and most reports in the literature are from autopsies. We describe a patient with undiagnosed primary pulmonary hypertension suffering from pulmonary artery dissection that subsequently underwent surgical repair and in addition review the current literature on this topic. Ó 2015 Elsevier Inc. All rights reserved.
Keywords: Pulmonary dissection Pulmonary hypertension Surgical treatment Pulmonary aneurysm Reconstruction
Introduction Pulmonary artery dissection is extremely rare and has been reported in less than 100 patients, most of them diagnosed postmortem, indicating that these patients succumb to cardiogenic shock or sudden death.1 Of the known cases, 24 were diagnosed alive. Successful repair of the pulmonary artery has been described in only seven cases. We report the outcome after surgical resection of the central pulmonary artery (PA) and reconstruction with grafts in a patient suffering from aneurysm and dissection of the pulmonary artery. Case report A 55-year old man with a previous history of malignant melanoma and one episode of metastasis to the lung, allegedly in remission for 20 years, was admitted due to progressive exertional dyspnea. He was diagnosed with a pulmonary artery aneurysm and
Funding and financial disclosures: There are no relevant financial disclosures from any of the co-authors. * Corresponding author. Transplant Institute, Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, University of Gothenburg, SE-413 45, Gothenburg, Sweden. Tel.: þ46 31 342 88 63, þ46 70 420 36 80 (mobile); fax: þ46 31 41 79 91. E-mail address: [email protected] (G. Dellgren). 0147-9563/$ e see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.hrtlng.2015.06.006
dissection by CT-scan (Fig. 1aec) and referred for surgical intervention. The CT-scan did not reveal any pericardial effusion. Preoperative ultrasound demonstrated a hypertrophic right ventricle with a peak systolic pulmonary artery pressure of 80 mm Hg. After thorough evaluation and discussion with the patient it was decided to repair the dissected pulmonary artery. The patient was premedicated orally with oxazepam (5 mg). Before induction of anesthesia, an arterial cannula was placed in the left radial artery and a triple lumen (Arrow International, Inc., 2400 Bernville Road, Reading, PA 19605, USA) catheter was inserted into the left subclavian vein. A norepinephrine infusion was started to maintain mean arterial pressure (MAP) >70 mm Hg in order to sustain coronary blood flow and maintain interventricular dependence. By augmenting aortic root pressure in the setting of increased right ventricular (RV) afterload, RV ischemia was prevented.2 After 5 min of preoxygenation with FIO2 100% and 20 ppm NO, anesthesia was induced with ketamine (1.2 mg/kg), propofol (1 mg/ kg) and fentanyl (5 mg/kg). Tracheal intubation was facilitated with rocuronium (0.8 mg/kg). Anesthesia was maintained with sevoflurane in oxygen and 20 ppm inspired NO with a FIO2 necessary to keep PaO2 >15 kPa. Ventilation was volume-controlled to maintain PaCO2 between 5.0 and 5.5 kPa. A rapid infusion (AVA HF, Edwards Lifesciences, LLC, Irvine, CA 92614-5686 USA) catheter was inserted through the right internal jugular vein and a continuous cardiac output thermo dilution flow directed pulmonary artery (Edwards Lifesciences) catheter (PAC) was positioned in the superior caval
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Fig. 1. (a) Preoperative CT-scan demonstrating an aneurysm of the pulmonary artery (PA). In the ventral medial portion of the aneurysm is a small flap of the dissection membrane seen. (b) Preoperative CT-scan demonstrating a dissection of the pulmonary artery (PA). False (FL) and true lumens (TL) are seen. (c) Sagittal view showing the pulmonary valve and the proximal and distal dissection membranes in the ventral wall of the aneurysm of the pulmonary artery.
vein. A 6Tc TEE probe (Vivid E9, GE Healthcare) was used together with a Vivid E9 cardiovascular ultrasound system (Vivid E9 GE Healthcare, 9900 Innovation Drive, Wauwatosa, WI 53226, USA) to monitor cardiac function. Near infrared spectroscopy (INVOS, Somanetics Corporation, Troy, Michigan 48084, USA) with sensors placed on forehead was used during the entire procedure. Due to the risk of rupture of the aneurysm, the right femoral artery and vein were cannulated after heparinization and extracorporeal bypass circulation (ECC) was initiated. Then, standard sternotomy and pericardiotomy was safely performed. A view of the operative field is shown in Fig. 2a. During and after ECC, a continuous infusion of propofol was administered as well as incremental doses of fentanyl. The superior vena cava (SVC) was dissected free. Without clamping of the aorta, the main pulmonary trunk was incised down towards the left PA and the dissecting membrane was visualized (Fig. 2b). Another incision of the right PA was performed between the aorta and SVC, and extended into the right hilum passing the right upper lobe artery. A 30 mm Dacron graft was sutured with a 5-0 Prolene to the right PA and subsequently tunneled toward the left side in the remaining native pulmonary artery and sutured to the left PA with 5-0 Prolene, as described by Senbaklavaci et al.3 A 3 cm incision was performed in the middle of the interconnected graft and another 30 mm graft was sutured with 5-0 Prolene in a T-shaped fashion. Finally the proximal end of this graft was sutured to the sino-tubular junction of the pulmonary valve (Fig. 2c). The PAC was now floated into the pulmonary artery. Coming off bypass resulted in excessive diffuse bleeding due to pulmonary hypertension with systolic PA pressures around 100 mm Hg. Bypass was restarted and the pulmonary aneurysmal sac was closed around the graft. Before another attempt of weaning from bypass, the following treatment was instituted: inhalation of 20 ppm NO and 10.000 ng/mL, 10 mL/h prostaglandin I2 (PGI2, epoprostenol, FlolanÒ) in 100% oxygen was started (due to the synergistic vasodilator effect on pulmonary vascular resistance),1,2,4e8 as soon as the ventilator was turned back on. The external pacemaker was set at DDD 90/min. A bolus dose of milrinone 50 mg/kg was given and a milrinone infusion of 0.375 mg/ kg/min was started. Norepinephrine was infused targeting a MAP of 80 mm Hg. Pulmonary pressure remained high and almost equal to systemic pressure. CVP was targeted at 15e18 mm Hg. This second attempt was successful and followed by thorough hemostasis. The heparin effect was reversed with protamine sulfate until normal ACT values were achieved. Plasma, cryoprecipitate and platelets were given according to the ThromboElastoGram (TEG5000, Haemonetics Corporation, 400 Wood Road, Braintree, MA 02184, USA). Hemoglobin was 17 g/dL at the start of the operation and was kept above 10 g/dL by infusion of erythrocyte concentrates. At the end of
surgery, the NO could gradually be weaned. The wound was packed with gauze and without closing the sternum the patient was taken to the intensive care unit (ICU) with on-going infusion of milrinone, norepinephrine and propofol as well as aerosolized PGI2. Almost equalized pressures in the pulmonary and systemic circulation characterized the first couple of the days in ICU, despite the use of aerosolized PGI2. Two days later the patient was taken back for reoperation. Moderate amounts of blood clots were rinsed from the wound. The patient was edematous exhibiting hemorrhagic diathesis. Again, the wound was packed with gauze and the patient was taken to the ICU. At the fourth postoperative day PGI2 was discontinued and the sternum was closed. During closure the patient developed atrial fibrillation, which did not respond to electro conversions. During the evening the patient became increasingly unstable and required high doses of inotropic support (using Milrinone, Norepinephrine and Epinephrine). Despite treatment with Amiodarone, Metoprolol, Adenosine and numerous electro conversions, the atrial arrhythmias persisted. Veno-arterial extracorporeal membrane oxygenator (ECMO) was considered but refrained because of the poor prognosis. The sternum was re-opened in the ICU, but with no improvement in cardiac output. The patient died later that evening in cardiogenic shock. Discussion Dissection of the pulmonary artery is a rare condition with less than 100 reported cases in the literature. The vast majority of these are found in autopsies. The most common cause is congenital heart disease (most commonly persistent ductus arteriosus) but other causes include primary or secondary pulmonary hypertension, vascular inflammatory disease, aorto-pulmonary fistulas, connective tissue disease and catheter induced vessel wall injury. We have identified twenty-four cases where the patients were alive at the time of diagnosis (Table 1) in the literature. No clear consensus regarding how these patients are best managed exists. In fourteen cases the clinical outcome was reported as stable (follow-up 4 dayse6 years), in four cases the patients died shortly after diagnosis, one patient survived 12 months and in five cases the outcome was not reported. The reports of surviving patients demonstrate the feasibility of both conservative medical management (seven cases) and surgical repair (seven cases). In one case of surgical repair, bilateral lung transplantation was performed after 10 months,3 and in two cases of medical treatment heart and lung transplantation was performed after 4930 and 5018 days, respectively. Five of the patients had pericardial effusion at the time of diagnosis. Two of these underwent successful surgical repair, the third patient died before the operation was started.
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Fig. 2. (a) Perioperative view of an aneurysm of the pulmonary artery (PA). The aorta (Ao) was of normal size (32 mm diameter). Note the right coronary artery (RCA), which was grossly enlarged. (b) A longitudinal incision of the main pulmonary artery aneurysm exposes the dissection membrane (DM). The proximal portion of the false lumen contained organized blood clots, whereas the distal portion was an empty cul-de-sac.(c) A T-formed conduit was constructed to exclude the dissection and aneurysm. Two straight 30 mm Dacron grafts were used. The first graft (*) was sutured to the hilar regions of the left and right pulmonary arteries. Access was gained through the incision in the main pulmonary artery and an additional incision in the right pulmonary artery between the aorta and superior vena cava. A second graft (**) was used to connect the first graft to the sino-tubular junction of the pulmonary valve, which was found normal and competent. After completion of the conduit, the left and main pulmonary arteries were closed over the conduit, which greatly facilitated hemostasis.
Although our patient died, five days after the surgical procedure, we believe there are important lessons to be learned from this case. Firstly, the patient was diagnosed alive and evidently suffered from undiagnosed primary pulmonary hypertension. Prompt surgical repair was justified by both the presence of dissection and by the large size of the pulmonary aneurysm (>90 mm diameter). Secondly, the operative method previously described by Senbaklavaci et al3 was used to repair the pulmonary dissection and worked as described. An initial attempt to come off ECC without wrapping the aneurysmal sac was not successful due to high pulmonary pressures and profound bleeding. When eventually the wrapping of the aneurysmal sac was performed, ECC was discontinued with a reasonable amount of bleeding. The closure of the aneurysmal sac should have been done during the first ECC-run, otherwise the surgery was exactly performed as described by Senbaklavaci et al.3 Despite state-of-the-art treatment with NO and PGI2 the patient had also postoperatively pulmonary hypertension equivalent to systemic artery pressures.
Postoperative management of patients with pulmonary hypertension is a challenge and a well-recognized problem in cardiac surgery. In patients with chronic pulmonary hypertension, the RV undergoes hypertrophy in order to overcome the increased afterload. Due to the pressure overload, the interventricular septum bulges leftwards in diastole, impinging on LV filling. Cardiac output and aortic root pressures decrease. This in turn reduces RV coronary artery perfusion as the RV is perfused during both systole and diastole and depends on high aortic root pressure. Ischemia will ensue and lead to a downward spiral of RV function. In patients with RV decompensation, the RV stroke volume decreases and because the RV and LV are in series the LV stroke volume also is reduced, resulting in decreased cardiac output and systemic pressure. However, in the setting of RV failure, interventricular dependence causes the interventricular septum to move toward the RV in systole. As the interventricular septum is functionally part of the LV, the LV thus assists the RV in maintaining stroke volume. High systemic pressure makes the “LV assist” more efficient in
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Table 1 Pulmonary artery dissections in the litterature. Nr
Reference
Age
Sex
Underlying disease
Size (mm)
Pericard effusion
Initial treatment
Outcome (follow-up time)
PASP (mm Hg)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Rosenson, 19869 Steurer, 199010 Kameyama, 199211 Stern, 199212 Lopez-Candales, 199513 Wunderbaldinger, 200014 Inayama, 200115 Senbaklavaci, 20013 Song, 200216 Areco, 200317 Tønder, 200418 Smalcelj, 200519 Khattar, 20051 Wuyts, 200630 Neimatallah, 200720 Li, 200921
59 64 n/a 27 56 22 59 34 42 52 39 44 56 48 44 4
F F M M M F F F M F M F F F M M
80 n/a n/a 75 60 85 n/a 80 n/a 91 50 157 60 n/a 65 n/a
No No No No No Yes No Yes No n/a No Yes No No Yes n/a
n/a Medical Surgery n/a Surgery Surgery Surgery Surgery, Medical Medical Medical Medical Medical Medical Planned surgery Surgery
n/a Stable (1 year) Stable n/a Stable (1 week) Stable (10 days) Stable (5 years) Stable (19 months) Died after 4 days Died after 2 weeks Stable (6 years) Died after 12 months Stable (12 months) Stable Died before surgery Stable
100 102 n/a 79 30 n/a “Normal” 120 n/a 90 n/a 80 75e80 70 140 n/a
17
Hoye, 200922
n/a
F
n/a
No
Medical
n/a
n/a
18 19 20 21 22 23 24
Mohammad, 200923 Nishimura, 200924 Rasalkar, 201025 Peng, 201026 Sehdev, 201027 Zhao, 201028 Matsumoto, 201229
51 80 48 n/a 51 49 97
F M F n/a F F F
Mitral valve stenosis PPH Aortopulm. fistula PPH? Pulmonary valve stenosis PPH Pulmonary embolism PPH VSD, Eisenmenger PPH VSD, Eisenmenger PPH Secondary PH (COPD) VSD, PH PDA Pulmonary valve stenosis, balloon valvuloplasty Obesity, hypo-ventilation syndrome, PH COPD Aortopulm. fistula SLE, PH Eisenmenger COPD PDA, Eisenmenger Heart failure
Normal n/a n/a n/a 27 n/a n/a
No n/a No n/a No n/a Yes
Medical Surgery Medical n/a Medical Planned surgery Medical
Stable (1 year) Stable (6 months) Stable n/a
Normal n/a n/a n/a Normal n/a n/a
Died before surgery Stable (2 years)
PASP ¼ Pulmonary artery systolic pressure, PPH ¼ Primary pulmonary hypertension, VSD ¼ Ventricular septal defect, PH ¼ Pulmonary hypertension, COPD ¼ Chronic obstructive pulmonary disease, PDA ¼ Patent ductus arteriosus.
supporting the RV, so all measures that improve LV function and maintain systemic pressure will ultimately improve RV function. In the operating theater and in the ICU, it is therefore appropriate to take a multimodal approach to RV failure and pulmonary hypertension. As previously mentioned, inhaled therapy with NO alone or in combination with PGI2 may selectively reduce pulmonary vascular resistance in patients with reversible high PVR. Hypotension must be treated aggressively in order to maintain aortic root pressure and coronary perfusion as well maintaining interventricular dependence. While optimizing fluid status and RV preload, it is critical not to overfill the failing RV. Inotropic support with milrinone, dopamine or levosimendan, usually in combination with norepinephrine to maintain systemic pressure, may be considered for RV failure. All this was done, and we believe the postoperative RV failure was related to a systemic inflammatory response syndrome commonly seen after ECC. Since surgery had been done without cross-clamping the aorta no ischemia had affected the heart that would result in failure. An intra-aortic balloon pump may improve coronary perfusion.31,32 As a last resort, ECMO may be considered as a bridge to transplantation.33,34 Despite the multimodal approach to RV failure and pulmonary hypertension, the patient’s clinical condition deteriorated in conjunction with a therapy resistant atrial arrhythmia. The fact that the patient had undergone extensive cardiac surgery with ensuing RV failure made the option of starting ECMO therapy controversial. It was deemed unlikely that the patient could be weaned from ECMO in the near future and using ECMO as a bridge to lung transplantation was considered futile in this setting. The patient died in cardiogenic shock. In conclusion We conclude that since the postoperative management of patients with untreated severe pulmonary hypertension is extremely difficult, it may be more appropriate to manage patients with pulmonary artery aneurysm/dissection medically in the acute
phase. At a later stage, bilateral lung transplantation using the “en bloc” technique, where the main pulmonary artery is preserved from the donor,35,36 can be performed. Even if this would require close monitoring with readiness to perform emergency surgery if pericardial effusion should develop, we would now favor this option in these patients that have untreated pulmonary hypertension. Acknowledgment This work was supported by grants from the Swedish HeartLung Foundation [grant number 20130497]; the Jan Elgqvist Foundation and a Strategic Research Grant of the Sahlgrenska University Hospital [grant number 77330]. Conflicts of interest: none declared. References 1. Khattar RS. Pulmonary artery dissection: an emerging cardiovascular complication in surviving patients with chronic pulmonary hypertension. Heart. 2005;91:142e145. 2. Price LC, Wort SJ, Finney SJ, Marino PS, Brett SJ. Pulmonary vascular and right ventricular dysfunction in adult critical care: current and emerging options for management: a systematic literature review. Crit Care. 2010;14:R169. 3. Senbaklavaci Ö, Kaneko Y, Bartunek A, et al. Rupture and dissection in pulmonary artery aneurysms: incidence, cause, and treatmentdReview and case report. J Thorac Cardiovasc Surg. 2001;121:1006e1008. 4. Vater Y, Martay K, Dembo G, Bowdle TA, Weinbroum AA. Intraoperative epoprostenol and nitric oxide for severe pulmonary hypertension during orthotopic liver transplantation: a case report and review of the literature. Med Sci Monit. 2006;12:CS115e118. 5. Flondor M, Merkel M, Hofstetter C, Irlbeck M, Frey L, Zwissler B. The effect of inhaled nitric oxide and inhaled iloprost on hypoxaemia in a patient with pulmonary hypertension after pulmonary thrombarterectomy. Anaesthesia. 2006;61:1200e1203. 6. Dani C, Pavoni V, Corsini I, et al. Inhaled nitric oxide combined with prostacyclin and adrenomedullin in acute respiratory failure with pulmonary hypertension in piglets. Pediatr Pulmonol. 2007;42:1048e1056. 7. Kieler-Jensen N, Lundin S, Ricksten SE. Vasodilator therapy after heart transplantation: effects of inhaled nitric oxide and intravenous prostacyclin, prostaglandin E1, and sodium nitroprusside. J Heart Lung Transplant. 1995;14: 436e443.
C.J. Malm et al. / Heart & Lung 44 (2015) 453e457 8. Haraldsson A, Kieler-Jensen N, Nathorst-Westfelt U, Bergh CH, Ricksten SE. Comparison of inhaled nitric oxide and inhaled aerosolized prostacyclin in the evaluation of heart transplant candidates with elevated pulmonary vascular resistance. Chest. 1998;114:780e786. 9. Rosenson RS, Sutton MS. Dissecting aneurysm of the pulmonary trunk in mitral stenosis. Am J Cardiol. 1986;58:1140e1141. 10. Steurer J, Jenni R, Medici TC, Vollrath T, Hess OM, Siegenthaler W. Dissecting aneurysm of the pulmonary artery with pulmonary hypertension. Am Rev Respir Dis. 1990;142:1219e1221. 11. Kameyama T, Nakayama S, Okabayashi H, Nomoto S, Okamoto Y, Ban T. A case report of successful repair of an aortopulmonary fistula with partial dissection of the pulmonary artery. Nihon Kyobu Geka Gakkai Zasshi. 1992;40:432e434. 12. Stern EJ, Graham C, Gamsu G, Golden JA, Higgins CB. Pulmonary artery dissection: MR findings. J Comput Assist Tomogr. 1992;16:481e483. 13. Lopez-Candales A, Kleiger RE, Aleman-Gomez J, Kouchoukos NT, Botney MD. Pulmonary artery aneurysm: review and case report. Clin Cardiol. 1995;18: 738e740. 14. Wunderbaldinger P, Bernhard C, Uffmann M, Kürkciyan I, Senbaklavaci O, Herold CJ. Acute pulmonary trunk dissection in a patient with primary pulmonary hypertension. J Comput Assist Tomogr. 2000;24:92e95. 15. Inayama Y, Nakatani Y, Kitamura H. Pulmonary artery dissection in patients without underlying pulmonary hypertension. Histopathology. 2001;38:435e442. 16. Song EK, Kolecki P. A case of pulmonary artery dissection diagnosed in the Emergency Department. J Emerg Med. 2002;23:155e159. 17. Areco D, Pizzano N. Pulmonary artery dissection: echocardiographic findings and diagnosis. Echocardiography. 2003;20:375e377. 18. Tønder N. Pulmonary artery dissection in a patient with Eisenmenger syndrome treated with heart and lung transplantation. Eur J Echocardiogr. 2004;5: 228e230. 19. Smalcelj A, Brida V, Samarzija M, Matana A, Margetic E, Drinkovic N. Giant, dissecting, high-pressure pulmonary artery aneurysm: case report of a 1-year natural course. Tex Heart Inst J. 2005;32:589. From the Texas Heart Institute of St. Luke’s Episcopal Hospital, Texas Children’s Hospital. 20. Neimatallah MA, Hassan W, Moursi M, Kadhi Al Y. CT findings of pulmonary artery dissection. Br J Radiol. 2007;80:e61ee63. 21. Li Q, Wang A, Li D, et al. Dissecting aneurysm of the main pulmonary artery: a rare complication of pulmonary balloon valvuloplasty diagnosed 1 month after the procedure. Circulation. 2009;119:761e763.
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22. Hoye SL, Gale CP, Tolan DJM, Pepper CB. An unusual presentation of pulmonary artery dissection. Thorax. 2009;64:368. 23. Mohammad K, Sahlol M, Egiebor O, Sadikot RT. Idiopathic pulmonary artery dissection: a case report. J Med Case Rep. 2009;3:7426. 24. Nishimura Y, Okamura Y, Uchita S, Honda K. Abrupt rupture of an aortic arch aneurysm into the pulmonary artery. Eur J Cardiothorac Surg. 2009;36:212e 213. 25. Rasalkar DD, Paunipagar BK, Chu W. Segmental pulmonary artery dissection in systemic lupus erythematosus. J HK Coll Radiol. 2010;13:29e31. 26. Peng L-Q, Yu J-Q, Chu Z-G, Yuan H-M. A rare case of right and left pulmonary artery dissections on 64-slice multidetector computed tomography. J Thorac Imaging. 2010;1. 27. Sehdev A, Dhoble A. Pulmonary artery dissection (PAD): a very unusual cause of chest pain. J Hosp Med. 2010;5:313e316. 28. Zhao Y, Li ZA, Henein MY. PDA with Eisenmenger complicated by pulmonary artery dissection. Eur J Echocardiogr. 2010;11:E32. 29. Matsumoto A, Kawasaki T, Takeoka M, et al. Silent pulmonary artery dissection in a centenarian. J Cardiol Cases. 2012;5:e36ee38. 30. Wuyts WA, Herijgers P, Budts W, De Wever W, Delcroix M. Extensive dissection of the pulmonary artery treated with combined heart-lung transplantation. J Thorac Cardiovasc Surg. 2006;132:205e206. 31. Arafa OE, Geiran OR, Andersen K, Fosse E, Simonsen S, Svennevig JL. Intraaortic balloon pumping for predominantly right ventricular failure after heart transplantation. Ann Thorac Surg. 2000;70:1587e1593. 32. Darrah WC, Sharpe MD, Guiraudon GM, Neal A. Intraaortic balloon counterpulsation improves right ventricular failure resulting from pressure overload. Ann Thorac Surg. 1997;64:1718e1723. discussion 1723e4. 33. Gregoric ID, Chandra D, Myers TJ, Scheinin SA, Loyalka P, Kar B. Extracorporeal membrane oxygenation as a bridge to emergency heart-lung transplantation in a patient with idiopathic pulmonary arterial hypertension. J Heart Lung Transplant. 2008;27:466e468. 34. Hsu H-H, Ko W-J, Chen J-S, et al. Extracorporeal membrane oxygenation in pulmonary crisis and primary graft dysfunction. J Heart Lung Transplant. 2008;27:233e237. 35. Dark JH, Patterson GA, Al-Jilaihawi AN, Hsu H, Egan T, Cooper JD. Experimental en bloc double-lung transplantation. Ann Thorac Surg. 1986;42:394e398. 36. Patterson GA, Cooper JD, Goldman B, et al. Technique of successful clinical double-lung transplantation. Ann Thorac Surg. 1988;45:626e633.
Contents lists available at ScienceDirect
Heart & Lung journal homepage: www.heartandlung.org
Pulmonary artery dissection in a patient with undiagnosed pulmonary hypertension e A case report and review of literature Carl Johan Malm, MD a, Lisa Ternström, MD a, Kirsten Jörgensen, MD, PhD b, Göran Dellgren, MD, PhD a, * a b
Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden Department of Cardiothoracic Anesthesia, Sahlgrenska University Hospital, Gothenburg, Sweden
a r t i c l e i n f o
a b s t r a c t
Article history: Received 1 April 2015 Received in revised form 7 June 2015 Accepted 9 June 2015 Available online 4 July 2015
Pulmonary artery dissection is rare and highly lethal and most reports in the literature are from autopsies. We describe a patient with undiagnosed primary pulmonary hypertension suffering from pulmonary artery dissection that subsequently underwent surgical repair and in addition review the current literature on this topic. Ó 2015 Elsevier Inc. All rights reserved.
Keywords: Pulmonary dissection Pulmonary hypertension Surgical treatment Pulmonary aneurysm Reconstruction
Introduction Pulmonary artery dissection is extremely rare and has been reported in less than 100 patients, most of them diagnosed postmortem, indicating that these patients succumb to cardiogenic shock or sudden death.1 Of the known cases, 24 were diagnosed alive. Successful repair of the pulmonary artery has been described in only seven cases. We report the outcome after surgical resection of the central pulmonary artery (PA) and reconstruction with grafts in a patient suffering from aneurysm and dissection of the pulmonary artery. Case report A 55-year old man with a previous history of malignant melanoma and one episode of metastasis to the lung, allegedly in remission for 20 years, was admitted due to progressive exertional dyspnea. He was diagnosed with a pulmonary artery aneurysm and
Funding and financial disclosures: There are no relevant financial disclosures from any of the co-authors. * Corresponding author. Transplant Institute, Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, University of Gothenburg, SE-413 45, Gothenburg, Sweden. Tel.: þ46 31 342 88 63, þ46 70 420 36 80 (mobile); fax: þ46 31 41 79 91. E-mail address: [email protected] (G. Dellgren). 0147-9563/$ e see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.hrtlng.2015.06.006
dissection by CT-scan (Fig. 1aec) and referred for surgical intervention. The CT-scan did not reveal any pericardial effusion. Preoperative ultrasound demonstrated a hypertrophic right ventricle with a peak systolic pulmonary artery pressure of 80 mm Hg. After thorough evaluation and discussion with the patient it was decided to repair the dissected pulmonary artery. The patient was premedicated orally with oxazepam (5 mg). Before induction of anesthesia, an arterial cannula was placed in the left radial artery and a triple lumen (Arrow International, Inc., 2400 Bernville Road, Reading, PA 19605, USA) catheter was inserted into the left subclavian vein. A norepinephrine infusion was started to maintain mean arterial pressure (MAP) >70 mm Hg in order to sustain coronary blood flow and maintain interventricular dependence. By augmenting aortic root pressure in the setting of increased right ventricular (RV) afterload, RV ischemia was prevented.2 After 5 min of preoxygenation with FIO2 100% and 20 ppm NO, anesthesia was induced with ketamine (1.2 mg/kg), propofol (1 mg/ kg) and fentanyl (5 mg/kg). Tracheal intubation was facilitated with rocuronium (0.8 mg/kg). Anesthesia was maintained with sevoflurane in oxygen and 20 ppm inspired NO with a FIO2 necessary to keep PaO2 >15 kPa. Ventilation was volume-controlled to maintain PaCO2 between 5.0 and 5.5 kPa. A rapid infusion (AVA HF, Edwards Lifesciences, LLC, Irvine, CA 92614-5686 USA) catheter was inserted through the right internal jugular vein and a continuous cardiac output thermo dilution flow directed pulmonary artery (Edwards Lifesciences) catheter (PAC) was positioned in the superior caval
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Fig. 1. (a) Preoperative CT-scan demonstrating an aneurysm of the pulmonary artery (PA). In the ventral medial portion of the aneurysm is a small flap of the dissection membrane seen. (b) Preoperative CT-scan demonstrating a dissection of the pulmonary artery (PA). False (FL) and true lumens (TL) are seen. (c) Sagittal view showing the pulmonary valve and the proximal and distal dissection membranes in the ventral wall of the aneurysm of the pulmonary artery.
vein. A 6Tc TEE probe (Vivid E9, GE Healthcare) was used together with a Vivid E9 cardiovascular ultrasound system (Vivid E9 GE Healthcare, 9900 Innovation Drive, Wauwatosa, WI 53226, USA) to monitor cardiac function. Near infrared spectroscopy (INVOS, Somanetics Corporation, Troy, Michigan 48084, USA) with sensors placed on forehead was used during the entire procedure. Due to the risk of rupture of the aneurysm, the right femoral artery and vein were cannulated after heparinization and extracorporeal bypass circulation (ECC) was initiated. Then, standard sternotomy and pericardiotomy was safely performed. A view of the operative field is shown in Fig. 2a. During and after ECC, a continuous infusion of propofol was administered as well as incremental doses of fentanyl. The superior vena cava (SVC) was dissected free. Without clamping of the aorta, the main pulmonary trunk was incised down towards the left PA and the dissecting membrane was visualized (Fig. 2b). Another incision of the right PA was performed between the aorta and SVC, and extended into the right hilum passing the right upper lobe artery. A 30 mm Dacron graft was sutured with a 5-0 Prolene to the right PA and subsequently tunneled toward the left side in the remaining native pulmonary artery and sutured to the left PA with 5-0 Prolene, as described by Senbaklavaci et al.3 A 3 cm incision was performed in the middle of the interconnected graft and another 30 mm graft was sutured with 5-0 Prolene in a T-shaped fashion. Finally the proximal end of this graft was sutured to the sino-tubular junction of the pulmonary valve (Fig. 2c). The PAC was now floated into the pulmonary artery. Coming off bypass resulted in excessive diffuse bleeding due to pulmonary hypertension with systolic PA pressures around 100 mm Hg. Bypass was restarted and the pulmonary aneurysmal sac was closed around the graft. Before another attempt of weaning from bypass, the following treatment was instituted: inhalation of 20 ppm NO and 10.000 ng/mL, 10 mL/h prostaglandin I2 (PGI2, epoprostenol, FlolanÒ) in 100% oxygen was started (due to the synergistic vasodilator effect on pulmonary vascular resistance),1,2,4e8 as soon as the ventilator was turned back on. The external pacemaker was set at DDD 90/min. A bolus dose of milrinone 50 mg/kg was given and a milrinone infusion of 0.375 mg/ kg/min was started. Norepinephrine was infused targeting a MAP of 80 mm Hg. Pulmonary pressure remained high and almost equal to systemic pressure. CVP was targeted at 15e18 mm Hg. This second attempt was successful and followed by thorough hemostasis. The heparin effect was reversed with protamine sulfate until normal ACT values were achieved. Plasma, cryoprecipitate and platelets were given according to the ThromboElastoGram (TEG5000, Haemonetics Corporation, 400 Wood Road, Braintree, MA 02184, USA). Hemoglobin was 17 g/dL at the start of the operation and was kept above 10 g/dL by infusion of erythrocyte concentrates. At the end of
surgery, the NO could gradually be weaned. The wound was packed with gauze and without closing the sternum the patient was taken to the intensive care unit (ICU) with on-going infusion of milrinone, norepinephrine and propofol as well as aerosolized PGI2. Almost equalized pressures in the pulmonary and systemic circulation characterized the first couple of the days in ICU, despite the use of aerosolized PGI2. Two days later the patient was taken back for reoperation. Moderate amounts of blood clots were rinsed from the wound. The patient was edematous exhibiting hemorrhagic diathesis. Again, the wound was packed with gauze and the patient was taken to the ICU. At the fourth postoperative day PGI2 was discontinued and the sternum was closed. During closure the patient developed atrial fibrillation, which did not respond to electro conversions. During the evening the patient became increasingly unstable and required high doses of inotropic support (using Milrinone, Norepinephrine and Epinephrine). Despite treatment with Amiodarone, Metoprolol, Adenosine and numerous electro conversions, the atrial arrhythmias persisted. Veno-arterial extracorporeal membrane oxygenator (ECMO) was considered but refrained because of the poor prognosis. The sternum was re-opened in the ICU, but with no improvement in cardiac output. The patient died later that evening in cardiogenic shock. Discussion Dissection of the pulmonary artery is a rare condition with less than 100 reported cases in the literature. The vast majority of these are found in autopsies. The most common cause is congenital heart disease (most commonly persistent ductus arteriosus) but other causes include primary or secondary pulmonary hypertension, vascular inflammatory disease, aorto-pulmonary fistulas, connective tissue disease and catheter induced vessel wall injury. We have identified twenty-four cases where the patients were alive at the time of diagnosis (Table 1) in the literature. No clear consensus regarding how these patients are best managed exists. In fourteen cases the clinical outcome was reported as stable (follow-up 4 dayse6 years), in four cases the patients died shortly after diagnosis, one patient survived 12 months and in five cases the outcome was not reported. The reports of surviving patients demonstrate the feasibility of both conservative medical management (seven cases) and surgical repair (seven cases). In one case of surgical repair, bilateral lung transplantation was performed after 10 months,3 and in two cases of medical treatment heart and lung transplantation was performed after 4930 and 5018 days, respectively. Five of the patients had pericardial effusion at the time of diagnosis. Two of these underwent successful surgical repair, the third patient died before the operation was started.
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Fig. 2. (a) Perioperative view of an aneurysm of the pulmonary artery (PA). The aorta (Ao) was of normal size (32 mm diameter). Note the right coronary artery (RCA), which was grossly enlarged. (b) A longitudinal incision of the main pulmonary artery aneurysm exposes the dissection membrane (DM). The proximal portion of the false lumen contained organized blood clots, whereas the distal portion was an empty cul-de-sac.(c) A T-formed conduit was constructed to exclude the dissection and aneurysm. Two straight 30 mm Dacron grafts were used. The first graft (*) was sutured to the hilar regions of the left and right pulmonary arteries. Access was gained through the incision in the main pulmonary artery and an additional incision in the right pulmonary artery between the aorta and superior vena cava. A second graft (**) was used to connect the first graft to the sino-tubular junction of the pulmonary valve, which was found normal and competent. After completion of the conduit, the left and main pulmonary arteries were closed over the conduit, which greatly facilitated hemostasis.
Although our patient died, five days after the surgical procedure, we believe there are important lessons to be learned from this case. Firstly, the patient was diagnosed alive and evidently suffered from undiagnosed primary pulmonary hypertension. Prompt surgical repair was justified by both the presence of dissection and by the large size of the pulmonary aneurysm (>90 mm diameter). Secondly, the operative method previously described by Senbaklavaci et al3 was used to repair the pulmonary dissection and worked as described. An initial attempt to come off ECC without wrapping the aneurysmal sac was not successful due to high pulmonary pressures and profound bleeding. When eventually the wrapping of the aneurysmal sac was performed, ECC was discontinued with a reasonable amount of bleeding. The closure of the aneurysmal sac should have been done during the first ECC-run, otherwise the surgery was exactly performed as described by Senbaklavaci et al.3 Despite state-of-the-art treatment with NO and PGI2 the patient had also postoperatively pulmonary hypertension equivalent to systemic artery pressures.
Postoperative management of patients with pulmonary hypertension is a challenge and a well-recognized problem in cardiac surgery. In patients with chronic pulmonary hypertension, the RV undergoes hypertrophy in order to overcome the increased afterload. Due to the pressure overload, the interventricular septum bulges leftwards in diastole, impinging on LV filling. Cardiac output and aortic root pressures decrease. This in turn reduces RV coronary artery perfusion as the RV is perfused during both systole and diastole and depends on high aortic root pressure. Ischemia will ensue and lead to a downward spiral of RV function. In patients with RV decompensation, the RV stroke volume decreases and because the RV and LV are in series the LV stroke volume also is reduced, resulting in decreased cardiac output and systemic pressure. However, in the setting of RV failure, interventricular dependence causes the interventricular septum to move toward the RV in systole. As the interventricular septum is functionally part of the LV, the LV thus assists the RV in maintaining stroke volume. High systemic pressure makes the “LV assist” more efficient in
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Table 1 Pulmonary artery dissections in the litterature. Nr
Reference
Age
Sex
Underlying disease
Size (mm)
Pericard effusion
Initial treatment
Outcome (follow-up time)
PASP (mm Hg)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Rosenson, 19869 Steurer, 199010 Kameyama, 199211 Stern, 199212 Lopez-Candales, 199513 Wunderbaldinger, 200014 Inayama, 200115 Senbaklavaci, 20013 Song, 200216 Areco, 200317 Tønder, 200418 Smalcelj, 200519 Khattar, 20051 Wuyts, 200630 Neimatallah, 200720 Li, 200921
59 64 n/a 27 56 22 59 34 42 52 39 44 56 48 44 4
F F M M M F F F M F M F F F M M
80 n/a n/a 75 60 85 n/a 80 n/a 91 50 157 60 n/a 65 n/a
No No No No No Yes No Yes No n/a No Yes No No Yes n/a
n/a Medical Surgery n/a Surgery Surgery Surgery Surgery, Medical Medical Medical Medical Medical Medical Planned surgery Surgery
n/a Stable (1 year) Stable n/a Stable (1 week) Stable (10 days) Stable (5 years) Stable (19 months) Died after 4 days Died after 2 weeks Stable (6 years) Died after 12 months Stable (12 months) Stable Died before surgery Stable
100 102 n/a 79 30 n/a “Normal” 120 n/a 90 n/a 80 75e80 70 140 n/a
17
Hoye, 200922
n/a
F
n/a
No
Medical
n/a
n/a
18 19 20 21 22 23 24
Mohammad, 200923 Nishimura, 200924 Rasalkar, 201025 Peng, 201026 Sehdev, 201027 Zhao, 201028 Matsumoto, 201229
51 80 48 n/a 51 49 97
F M F n/a F F F
Mitral valve stenosis PPH Aortopulm. fistula PPH? Pulmonary valve stenosis PPH Pulmonary embolism PPH VSD, Eisenmenger PPH VSD, Eisenmenger PPH Secondary PH (COPD) VSD, PH PDA Pulmonary valve stenosis, balloon valvuloplasty Obesity, hypo-ventilation syndrome, PH COPD Aortopulm. fistula SLE, PH Eisenmenger COPD PDA, Eisenmenger Heart failure
Normal n/a n/a n/a 27 n/a n/a
No n/a No n/a No n/a Yes
Medical Surgery Medical n/a Medical Planned surgery Medical
Stable (1 year) Stable (6 months) Stable n/a
Normal n/a n/a n/a Normal n/a n/a
Died before surgery Stable (2 years)
PASP ¼ Pulmonary artery systolic pressure, PPH ¼ Primary pulmonary hypertension, VSD ¼ Ventricular septal defect, PH ¼ Pulmonary hypertension, COPD ¼ Chronic obstructive pulmonary disease, PDA ¼ Patent ductus arteriosus.
supporting the RV, so all measures that improve LV function and maintain systemic pressure will ultimately improve RV function. In the operating theater and in the ICU, it is therefore appropriate to take a multimodal approach to RV failure and pulmonary hypertension. As previously mentioned, inhaled therapy with NO alone or in combination with PGI2 may selectively reduce pulmonary vascular resistance in patients with reversible high PVR. Hypotension must be treated aggressively in order to maintain aortic root pressure and coronary perfusion as well maintaining interventricular dependence. While optimizing fluid status and RV preload, it is critical not to overfill the failing RV. Inotropic support with milrinone, dopamine or levosimendan, usually in combination with norepinephrine to maintain systemic pressure, may be considered for RV failure. All this was done, and we believe the postoperative RV failure was related to a systemic inflammatory response syndrome commonly seen after ECC. Since surgery had been done without cross-clamping the aorta no ischemia had affected the heart that would result in failure. An intra-aortic balloon pump may improve coronary perfusion.31,32 As a last resort, ECMO may be considered as a bridge to transplantation.33,34 Despite the multimodal approach to RV failure and pulmonary hypertension, the patient’s clinical condition deteriorated in conjunction with a therapy resistant atrial arrhythmia. The fact that the patient had undergone extensive cardiac surgery with ensuing RV failure made the option of starting ECMO therapy controversial. It was deemed unlikely that the patient could be weaned from ECMO in the near future and using ECMO as a bridge to lung transplantation was considered futile in this setting. The patient died in cardiogenic shock. In conclusion We conclude that since the postoperative management of patients with untreated severe pulmonary hypertension is extremely difficult, it may be more appropriate to manage patients with pulmonary artery aneurysm/dissection medically in the acute
phase. At a later stage, bilateral lung transplantation using the “en bloc” technique, where the main pulmonary artery is preserved from the donor,35,36 can be performed. Even if this would require close monitoring with readiness to perform emergency surgery if pericardial effusion should develop, we would now favor this option in these patients that have untreated pulmonary hypertension. Acknowledgment This work was supported by grants from the Swedish HeartLung Foundation [grant number 20130497]; the Jan Elgqvist Foundation and a Strategic Research Grant of the Sahlgrenska University Hospital [grant number 77330]. Conflicts of interest: none declared. References 1. Khattar RS. Pulmonary artery dissection: an emerging cardiovascular complication in surviving patients with chronic pulmonary hypertension. Heart. 2005;91:142e145. 2. Price LC, Wort SJ, Finney SJ, Marino PS, Brett SJ. Pulmonary vascular and right ventricular dysfunction in adult critical care: current and emerging options for management: a systematic literature review. Crit Care. 2010;14:R169. 3. Senbaklavaci Ö, Kaneko Y, Bartunek A, et al. Rupture and dissection in pulmonary artery aneurysms: incidence, cause, and treatmentdReview and case report. J Thorac Cardiovasc Surg. 2001;121:1006e1008. 4. Vater Y, Martay K, Dembo G, Bowdle TA, Weinbroum AA. Intraoperative epoprostenol and nitric oxide for severe pulmonary hypertension during orthotopic liver transplantation: a case report and review of the literature. Med Sci Monit. 2006;12:CS115e118. 5. Flondor M, Merkel M, Hofstetter C, Irlbeck M, Frey L, Zwissler B. The effect of inhaled nitric oxide and inhaled iloprost on hypoxaemia in a patient with pulmonary hypertension after pulmonary thrombarterectomy. Anaesthesia. 2006;61:1200e1203. 6. Dani C, Pavoni V, Corsini I, et al. Inhaled nitric oxide combined with prostacyclin and adrenomedullin in acute respiratory failure with pulmonary hypertension in piglets. Pediatr Pulmonol. 2007;42:1048e1056. 7. Kieler-Jensen N, Lundin S, Ricksten SE. Vasodilator therapy after heart transplantation: effects of inhaled nitric oxide and intravenous prostacyclin, prostaglandin E1, and sodium nitroprusside. J Heart Lung Transplant. 1995;14: 436e443.
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