Heterotopic Heart Transplantation: Technical Considerations Jack Copeland, MD, Hannah Copeland, MD  Operative Techniques in Thoracic and Cardiovascular Surgery  Volume 21, Issue 3, Pages 269-280 (September 2016) DOI: 10.1053/j.optechstcvs.2017.05.004 Copyright © 2017 Terms and Conditions

Figure 1 Barnard's heterotopic technique established a donor heart in parallel with the native heart. The left (not shown) and right atria of the donor heart were anastomosed to the respective native heart chambers, and great vessel anastomoses were made between the respective great vessels. A graft was required to give a tension-free connection of the pulmonary arteries. Ao, aorta, LV, left ventricle; PA, pulmonary arteries. Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 2 During the donor procurement, the extra length of the ascending aorta is taken. Lines of resection are the dotted lines. The length necessary is judged at the time of the transplant. We have used the entire ascending aorta. The extra length of the superior vena cava (SVC) is necessary to establish a pathway for cardiac biopsy.9 Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 3 The right pulmonary veins may be taken with a donor right lung, but the left pulmonary veins are transected individually and taken with the donor heart then oversewn with a 4-0 polypropylene suture. This may preclude transplantation of the donor left lung. In situations where left lung harvest is critical, pulmonary venous cuff length suitable for transplant could be taken. Then depending on the size of the donor left atrium, the atriotomy at the site of the left pulmonary venous cuff transection could be closed primarily or with a patch. We have no experience with these modifications, and they have not been reported. The major consideration is to have an adequate size donor left atrium to serve as an unobstructed conduit to the donor left ventricle. The entire SVC to the level of the innominate vein is taken with the specimen. The transected inferior vena cava is oversewn with a 4-0 polypropylene suture. Procurement includes placement of an aortic cardioplegia line and starting the cardioplegic solution. We have used a 16-gauge intravenous catheter and compression on the bag of solution. The left and right sides are decompressed quickly by major incisions at the superior right pulmonary vein-left atrial junction and the inferior vena cava. As soon as the heart is decompressed, an aortic cross clamp is placed and the remainder of the cardioplegic solution is delivered (usually 1 liter of crystalloid solution). Then the heart is carefully removed along the transection lines shown. IVC = inferior vena cava. Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 4 The recipient pericardium is incised transversely near the diaphragm, on the right side near the right pulmonary artery and half way in between, to allow the cardiac graft to hang gently into the right chest without strangulation by the pericardium. Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 5 Recipient bicaval cannulation with placement of superior and inferior vena cava tapes, slightly distal aortic cannulation, moderate systemic hypothermia on cardiopulmonary bypass (32°C), and standard native heart cardioplegia are used. The aorta is cross-clamped. Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 6 The first anastomosis is between the donor left atriotomy and a generous incision in the native heart left atrium near Waterson's groove. We use a running 3-0 polypropylene suture with an SH needle. Now assessment of the right pericardial edge is essential. Further relaxation of the right pericardium is indicated for any hint that it might constrict the native to donor heart left atrial pathway. There should be no gradient across this anastomosis at separation from cardiopulmonary bypass.LA, left atrium; RA, right atrium. Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 7 Next is an end-to-side aorto-aortic anastomosis with a 4-0 polypropylene suture with a BB needle. The aortotomy is a longitudinal linear incision that is slightly smaller than the obliquely cut end of the donor aorta. We usually start with an 11 blade and extend the incision with a Potts scissor. Once the aortic anastomosis is completed, the aortic cross clamp is removed with the patient in steep Trendelenburg position. De-airing, along with defibrillation, ventilation, and transesophageal echocardiogram, is begun (discussed further in Figure 9). Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 8 Next, an end-to-side donor main pulmonary artery to native right atrial free wall anastomosis is done with a 4-0 or 5-0 polypropylene suture with a C1 needle. The right atrial free wall incision is about the same size as the diameter of the cut end of the donor pulmonary artery. This connection decompresses the donor right side of coronary venous return. It could also be used as a pathway for donor right ventricular biopsy. Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 9 The donor to recipient SVC anastomosis is made to establish a conduit for cardiac biopsy. It is an end-to-side anastomosis with a 5-0 polypropylene suture with a C1 needle, and we use a side biting clamp on the SVC. The anastomosis is made as large as can be accommodated by the size of the donor SVC and the available recipient SVC. Four metallic clips are placed around this anastomosis (A) as markers for later use during cardiac biopsy under fluoroscopy.9 One problem with this anastomosis is the presence of previously placed multiple pacing and defibrillating wires usually associated with some SVC fibrosis. For this reason, selection of a favorable site is important and locations other than the native SVC might be considered, such as the body of the right atrium. The important goal is to have a widely patent entry for a sheath and bioptome. The pulmonary artery to right atrium and SVC to SVC anastomoses are made with the aortic cross clamp removed and the patient in steep head down position (B). Defibrillation may be necessary for each heart and is applied directly with paddles on each side of the respective ventricles to maximize the trans-myocardial delivery of electrical energy; usually 5 to 20 Joules for each heart is sufficient. Vigorous de-airing with the patient in steep head down position and aortic cross-clamp removed with resuscitation of both hearts during rewarming precedes discontinuation of cardiopulmonary bypass. Just before the aortic cross clamp is removed, 20-gauge needle punctures are made on the donor and recipient aortas at the highest point (most anterior) of each vessel to allow free bleeding and provide an optimal exit for air. These sites are later closed with 4-0 polypropylene after de-airing is complete. We agitate both hearts and elevate the apices of both hearts and aspirate from the elevated apices with a 20-gauge needle on a 10-ml syringe. Both apical sites are later closed with 3-0 polypropylene. Transesophageal echocardiogram is used for evaluation of retained air (C). Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions

Figure 10 Once implanted, the donor heart sits close to the native heart. At this point assessment of the anastomoses, graft position, effect, if any, of the right pericardium (more pericardial relaxation may be indicated), the relationship to the right lung, and most important, the function of the donor left ventricle and the recipient right ventricle. Cardiopulmonary bypass weaning is attempted only after all retained air has been removed. Additional maneuvers include decreasing cardiopulmonary bypass flow for 1-2 minutes, giving volume, and allowing the donor and recipient hearts to pump along with hyperinflation of the lungs to remove any pulmonary venous air. At least 3 or 4 of these maneuvers are part of the routine. We spend about 30 minutes de-airing. This also allows for complete evaluation of the position and function of the heterotopic graft. Operative Techniques in Thoracic and Cardiovascular Surgery 2016 21, 269-280DOI: (10.1053/j.optechstcvs.2017.05.004) Copyright © 2017 Terms and Conditions