Cardiac Autotransplantation Shanda H. Blackmon, MD,* and Michael J. Reardon, MD Cardiac tumors are unusual and cardiac malignancy, usually sarcoma, is a very small subset of these. The literature on cardiac sarcomas of the left heart often exhibited multiple operations for local recurrence, which we believed was related to inadequate resection, likely exacerbated by poor anatomic exposure of the posterior heart for complex resection and reconstruction. Since November 1998, we have approached large complex sarcoma of the left atrium or *Division of Thoracic Surgery, Department of Surgery, The Methodist Hospital, Houston, Texas. Division of Cardiac Surgery, Department of Cardiovascular Surgery, The Methodist DeBakey Heart and Vascular Center, The Methodist Hospital, Houston, Texas. Dr. Reardon reports consulting fees from Medtronic. Address reprint requests to Michael J. Reardon, MD, Cardiovascular Surgery Associates, The Methodist Hospital, 6550 Fannin Street, Suite 1401, Houston, TX 77030. E-mail: mreardon@tmhs.org left ventricle using the technique of cardiac explantation, ex vivo tumor resection, and cardiac reconstruction and reimplantation of the heart cardiac autotransplantation. This allows complete exposure of left heart structures for aggressive resection and accurate reconstruction, permitting the removal if necessary of the entire left atrium and good exposure for removal of intracavitary left ventricular tumors. This technique has also been applied to large complex benign left atrial tumors such as giant myxoma and paraganglioma. We have had only one local recurrence and no mortality when only cardiac autotransplantation was necessary in 19 patients. When pneumonectomy was required in addition to cardiac autotransplantation, the mortality was 57% (4/7 patients). Pneumonectomy is usually required due to complete involvement of the pulmonary veins and should be carefully looked for in the preoperative evaluation and considered a contraindication for surgery except in extreme circumstances. 1-12 1522-2942/$-see front matter 2010 Elsevier Inc. All rights reserved. doi:10.1053/j.optechstcvs.2010.03.002 147
148 S.H. Blackmon and M.J. Reardon Operative Technique Figure 1 The patient is positioned on the operating table supine for a standard median sternotomy. The pericardium is opened and suspended to form a pericardial cradle on the right side and remains unsuspended on the left. The left pleura is opened and the inferior left pericardium is widely incised to just above the phrenic nerve to allow the heart to be displaced into the left chest during reimplantation, if necessary. Aortic cannulation may be done in the surgeon s standard fashion. Venous cannulation is done with 24-Fr venous cannulae. One is placed directly into the superior vena cava and the second is placed into the inferior vena cava right atrial junction. The superior and inferior vena cava should both be extensively mobilized prior to cannulation. Care must be taken to cannulate far enough from the right atrium to leave sufficient cava above and below for reconstruction as this tissue tends to retract substantially on the noncardiac side of the division. IVC inferior vena cava; SVC superior vena cava.
Cardiac autotransplantation 149 Figure 2 If sufficient inferior vena cava is not available below the right atrium, we have used a 21-Fr percutaneous femoral vein cannula for inferior drainage. This allows direct clamping of the inferior vena cava without a cannula taking up space. IVC inferior vena cava; v vein.
150 S.H. Blackmon and M.J. Reardon Figure 3 Once cardiopulmonary bypass is established, the superior vena cava and inferior vena cava right atrial junction are widely mobilized and surrounded by tourniquets. If the percutaneous femoral cannula has been used for inferior drainage, then the inferior vena cava may be simply clamped with a vascular clamp. The interatrial groove is developed to define the separation between the left and right atria. The ascending aorta is circumferentially mobilized as is the main pulmonary artery. These maneuvers will simplify accurate cardiac excision after cross-clamp application. IVC inferior vena cava; RLPV right lower pulmonary vein; RPA right pulmonary artery; RUPV right upper pulmonary vein; SVC superior vena cava.
Cardiac autotransplantation 151 Figure 4 The aortic cross-clamp is applied and 10 ml/kg antegrade cold blood K cardioplegia is administered to achieve cardiac standstill. Retrograde cardioplegia is not used. The left atrium is incised to vent and decompress the heart. The superior vena cava is divided just beyond the right atrium. The right atrial inferior vena cava junction is divided next. With both of these maneuvers, care must be taken to leave adequate tissue on the caval side of the division as this tissue tends to retract substantially and reconstruction will be difficult if it is cut too short. The aorta is then divided about 1 cm distal to the sinotubular junction and the main pulmonary artery is divided just proximal to the bifurcation. IVC inferior vena cava; SVC superior vena cava.
152 S.H. Blackmon and M.J. Reardon Figure 5 The left atrium is now divided beginning as a normal interatrial opening for mitral valve surgery. The incision is then extended circumferentially around the remaining left atrium, passing midway between the left pulmonary veins posteriorly and the left atrial appendage and mitral valve anteriorly. With this maneuver, the complete heart may be removed from the chest and placed in a basin of ice slush.
Cardiac autotransplantation 153 Figure 6 (A) We begin by examining the posterior left atrium remaining in the chest and removing any tumor. Reconstruction of the posterior left atrium depends on the extent of resection necessary. (B) If only the area between the pulmonary veins needs to be removed, then this is reconstructed and bovine pericardium using a running 4-0 Prolene suture is used.
154 S.H. Blackmon and M.J. Reardon Figure 7 If there is minimal or no pulmonary vein cuff remaining after complete resection, then the veins can be brought through an appropriate opening cut into the pericardium and sutured with a 4-0 Prolene or in more extreme circumstances the vein can be replaced with a 10 mm Gore- Tex interposition graft between the remaining vein stump and an appropriate opening cut into the bovine pericardium. Figure 8 When the veins have been directly implanted into openings cut into the bovine pericardium, it is helpful to place darts into the corners of the bovine pericardium to make the reconstructed posterior left atrium rounded rather than flat.
Cardiac autotransplantation 155 Figure 9 Once the posterior left atrium is complete, attention is turned to the heart itself and any tumor remaining on the anterior left atrium. For left ventricular tumors, there is no posterior left atrial work to be done and resection can be completed through the mitral valve. In both intracavitary left ventricular sarcomas we have operated on, mitral valve replacement was necessary due to tumor involvement of the papillary muscles. The entire anterior left atrium can be safely resected leaving nothing but the mitral annulus, if necessary. Care must be taken to identify and avoid the circumflex coronary artery in this resection and reconstruction. SVC superior vena cava.
156 S.H. Blackmon and M.J. Reardon Figure 10 Mitral valve replacement is technically easy when necessary with the heart ex vivo. The resected anterior left atrium can be reconstructed with bovine pericardium as necessary. When the entire anterior left atrium must be removed, we have always needed to perform a mitral valve replacement also. We use tissue valves to avoid Coumadin in these patients, who are likely to require other procedures and have a decreased life expectancy due to the aggressive nature of this malignancy. When the entire anterior left atrium is removed along with the mitral valve, we reconstruct this by centering a large patch of bovine pericardium over the mitral annulus and cutting an appropriate opening to match the annular opening. We then place pledgetted 2-0 Ticron sutures with the pledgets on the left ventricular side through the pericardium and then through the prosthetic mitral valve. When these sutures are completed and tied, the bovine pericardium is sealed between the mitral annulus and the prosthetic valve and any excess pericardium can be trimmed as necessary.
Cardiac autotransplantation 157 Figure 11 After reconstruction of the anterior left atrium, we use a handheld cannula to directly inject cold blood K cardioplegia into the left main and then the right main coronaries. This allows us to identify and suture any bleeding sites from small coronary branches while easily accessible. a artery; SVC superior vena cava.
158 S.H. Blackmon and M.J. Reardon Figure 12 The heart is now transplanted back to its orthotopic position, beginning just above the left superior pulmonary vein and extending first inferiorly toward the inferior vena cava and then superiorly along the roof of the left atrium using a 48-inch 4-0 Prolene suture. Unlike in standard orthotopic cardiac transplantation where a smaller donor heart is usually placed into the space left by the removal of the usually much larger damaged recipient heart, there is often limited space in which to work. At this point, it is helpful to have widely opened the left pleura and inferior pericardium to allow the heart to be displaced into the left chest as necessary while constructing the left atrial suture line. As this suture line is completed, it is important to maintain the orientation of the superior vena cava and inferior vena cava anastomosis sites. At the completion of this suture line, it is not tied but instead a left atrial stump is placed and sutures held with a rubber-shod clamp.
Cardiac autotransplantation 159 Figure 13 (A) We next suture the inferior vena cava right atrial junction and then the superior vena cava right atrial junction with 5-0 Prolene sutures. (B) If either of these cannot be completed without undo tension, we have used self-constructed bovine pericardial tubes, Dacron grafts, or Gore-Tex grafts as short interposition grafts without any problems. IVC inferior vena cava; SVC superior vena cava.
160 S.H. Blackmon and M.J. Reardon Figure 14 The pulmonary artery is now anastomosed using a running 4-0 Prolene suture that is not tied at its completion. The aorta is then anastomosed using a running 4-0 Prolene suture. The caval stares are then released; the left atrial vent is removed and the left atrial suture line is tied. Appropriate Valsalva and other deairing maneuvers are performed and the pulmonary artery and aortic suture lines are tied. Warm blood K cardioplegia is then given antegrade and the aortic cross-clamp is removed. Atrial and ventricular pacing wires are placed. Conclusions Cardiac sarcoma is a rare disease with an often dismal prognosis. Treated without surgical resection, the survival at 1 year is about 10%. 13 The role of chemotherapy and radiation therapy as primary treatment remains both unsettled and unproven. The only treatment modality shown to extend survival is complete surgical resection. 12,14 Complete resection of left heart sarcoma, or large complex benign lesions, is complicated by the posterior location of the left heart struc-
Cardiac autotransplantation 161 tures. Cardiac explantation, ex vivo tumor resection with reconstruction, and cardiac reimplantation cardiac autotransplantation has proven a useful surgical technique in dealing with this anatomic limitation. Our experience has shown that excellent exposure is obtained and radical resection and reconstruction are facilitated by this approach. Acceptable mortality and morbidity are possible in experienced centers when only cardiac autotransplantation is needed. If extensive pulmonary involvement would require an additional pneumonectomy for complete tumor resection, we have found the surgical mortality to exceed 50%; surgery should be avoided under these circumstances. References 1. Cooley DA, Reardon MJ, Frazier OH, et al: Human cardiac explantation and autotransplantations: Application in a patient with a large cardiac pheochromocytoma. Texas Heart Inst J 12:171-176, 1985 2. Reardon MJ, DeFelice CA, Sheinbaum R, et al: Cardiac autotransplant for surgical treatment of a malignant neoplasm. Ann Thorac Surg 67: 1793-1795, 1999 3. Reardon MJ: Left atrial malignant fibrohistiocytoma: An extracorporeal resection prior to autotransplantation. Case report and image. Ann Thorac Surg 68:260, 1999 4. Conklin LD, Reardon, MJ: Autotransplantation of the heart for primary cardiac malignancy: Development and surgical technique. Tex Heart Inst J 29:105-108, 2002 5. Mery G, Reardon MJ, Law J, et al: A combined modality approach to recurrent cardiac sarcoma resulting in a prolonged remission: A case report. Chest 123:1766-1768, 2003 6. Bakaeen F, Reardon MJ, Coselli JS, et al: Surgical outcome in eightyfive patients with primary cardiac tumors. Am J Surg 186:641-647, 2003 7. Iskander SS, Ostrowski ML, Nagueh SF, et al: Growth of a left atrial sarcoma followed by resection and auto-transplantation. Ann Thorac Surg 79:1771-1774, 2005 8. Reardon MJ, Malaisrie SC, Walkes JC, et al: Cardiac autotransplantation for primary cardiac tumors. Ann Thorac Surg 82:645-650, 2006 9. Reardon MJ, Walkes JC, DeFelice CA, et al: Cardiac autotransplant for surgical resection of a primary malignant left ventricular tumor. Tex Heart Inst J 33:495-497, 2006 10. Blackmon SH, Patel AR, Bruckner BA, et al: Cardiac autotransplantation for malignant or complex primary left-heart tumors. Tex Heart Inst J 35:296-300, 2008 11. Bruckner BA, Saharia A, Aburto J, et al: Delayed left ventricular free wall rupture following cardiac sarcoma resection. Tex Heart Inst J 36:171-173, 2009 12. Bakaeen FG, Jaroszewski DE, Rice DC, et al: Outcomes after surgical resection of cardiac sarcoma in the multimodality treatment era. J Thorac Cardiovasc Surg 137:1454-1460, 2009 13. Neragi-Miandoab JK, Vlahakes GJ: Malignant tumors of the heart: A review of tumor type, diagnosis and therapy. Clin Oncol 19:748-756, 2007 14. Putnam JB Jr, Sweeney MS, Colon R, et al: Primary cardiac sarcomas. Ann Thorac Surg 51:906-910, 1991