The best treatment for patients with severe biventricular failure is heart transplantation. When a heart donor is not imminently available, long-term biventricular support as a bridge to transplant is the only realistic option. Total artificial heart (Syncardia, Tucson, AZ) and continuous flow durable biventricular assist device implantation are the two mid-term support options.1,2 Reports demonstrate comparable survival with total artificial heart and biventricular pump support as bridge to transplant.3,4 Although the left ventricular assist device implant technique is standardized, there are few right ventricular assist device (RVAD) surgical implant techniques described; both the right ventricle and the right atrium can be used for the pump implant.2,5 We describe a HeartWare (HW) (Medtronic, Fridley, MN) implant technique at the right atrium with pump fixation to the right anterior chest wall that prevents suction events and functions well until heart transplant occurs.
A 40-year-old male INTERMACS 1 with end-stage nonischemic cardiomyopathy was approved for left ventricular assist device (LVAD) implant as bridge to transplant. At the time of a HeartMate 3 LVAD (Abbott, Chicago, IL) implant, he underwent concomitant replacement of the aortic valve with tissue pericardial prosthesis and tricuspid valve ring annuloplasty for moderate aortic and tricuspid regurgitation. Because of severe right ventricular failure at the index procedure, temporary right ventricular support was instituted with Centrimag (Abbott), as previously described.6 The right ventricle did not recover and the patient underwent an HW RVAD implant. After initiation of cardiopulmonary bypass with bicaval venous drainage, the HW ring was secured with multiple Ethibond pledgeted circumferential sutures at the right atrial appendix (Figures 1 and 2). Two felt rings (Teflon; Dupont Co., Wilmington, DE) were placed between the right atrial wall and the ring to avoid deep penetration of the inflow cannula in the right atrium. A right atrial wall opening was created at the junction of atrial appendix-right atrial body with a cruciate incision followed by a circular opening and the HW pump was secured to the ring. The HW RVAD outflow graft was connected to the preexisting main pulmonary artery graft in end-to-end fashion with continuous 5-0 Prolene suture. Three No. 2 Prolene sutures were tied around the HW RVAD pump at the ring-pump junction 60° apart. A counter incision at the right fourth rib anterior chest wall level was made and the sutures were passed around the third and fourth ribs after opening the right pleural space. The HW RVAD and its outflow graft were wrapped with a Goretex membrane (Flagstaff, AZ) to facilitate RVAD explant in the future (Figures 1 and 3). The RVAD outflow graft was left long enough to take a gentle curve on the lateral wall of the heart. The RVAD drive line was exited at the patient’s right subcostal area and was connected to the pump controller. The RVAD and LVAD were started at a speed of 1,800 and 3,000 r/min, respectively, and gradually increased at 2,400 and 5,000 r/min, respectively, after separation from cardiopulmonary bypass. The three heavy Prolene sutures were tied around the third and fourth ribs after sternal approximation under transesophageal guidance to ensure optimal inflow RVAD cannula position at a safe distance from the interatrial septum. The final RVAD and LVAD speed was adjusted to ensure neutral position of the intra-atrial septum on transesophageal imaging. The patient had an uneventful recovery. After a period of rehabilitation, he underwent a successful heart transplant in 6 months. The RVAD was easily detached from the chest wall by cutting the anchoring stitches that were placed during the index procedure (Figure 1); both assist devices were functioning well until they were explanted. In our experience of five patients with the same technique of biventricular implant, we have not experienced any HW RVAD thrombosis during 5 months of median follow-up period. One patient expired from massive intracerebral hemorrhage.
Implant of the RVAD in the inferior wall of the right ventricle can potentially be problematic because the tricuspid subvalvular apparatus can obstruct the RVAD inflow cannula opening leading to RVAD pump thrombosis. When the HW is implanted at the anterior surface of the right ventricle, the assist device may compress the right ventricular outflow causing low RVAD flow and subsequent pump thrombosis.2,5 During our early experience with long-term biventricular support, we had one case of HW RVAD thrombosis that was implanted at the inferior wall of the right ventricle. Implantation of the RVAD in the right atrium avoids inflow cannula obstruction by the tricuspid valve sub valvular apparatus and right ventricular compression. Tran et al.7 described a case series of 11 patients with excellent results with biventricular support after implant of HW RVAD in the right atrium. Intrapericardial placement of the RVAD can be possible with the use of more spacers and adequate volume resuscitation. Fixation of the RVAD from the chest wall may overcome the potential suction event if the patient is volume depleted during the postoperative period. The addition of another surgical incision at the right anterior chest wall can cause some discomfort that improves with time as the surgical wound heals. The anchoring sutures may cause some residual discomfort that completely resolves when they are cut during the heart transplant. We decided to use HW for RVAD support because the size of the inflow cannula is smaller than HeartMate 3. Caution should be exercised during explant of the HW RVAD; placement of sternal retractor following sternal division before the HW is detached from the chest wall may transmit undue traction and tear the right atrium. Detachment of the HW from the chest wall is simple: Exposure is obtained with gentle elevation of the right hemi-sternum with an internal mammary retractor, followed by cutting the three anchoring sutures to the chest wall and removal of the wrapping Goretex membrane. We believe that the HW RVAD technique described is reliable when biventricular support is necessary and the explant technique is safe and reproducible at the time of the transplant.
1. Copeland JG, Smith RG, Arabia FA, et al. Total artificial heart bridge to transplantation: A 9-year experience with 62 patients. J Heart Lung Transplant 2004.23: 823–831.
2. Shehab S, Macdonald PS, Keogh AM, et al. Long-term biventricular HeartWare ventricular assist device support: Case series of right atrial and right ventricular implantation outcomes. J Heart Lung Transplant 2016.35: 466–473.
3. Cheng A, Trivedi JR, Van Berkel VH, Massey HT, Slaughter MS. Comparison of total artificial heart and biventricular assist device support as bridge-to-transplantation. J Card Surg 2016.31: 648–653.
4. Kirklin JK, Naftel DC, Pagani FD, et al. Seventh INTERMACS annual report: 15,000 patients and counting. J Heart Lung Transplant 2015.34: 1495–1504.
5. Krabatsch T, Stepanenko A, Schweiger M, et al. Alternative technique for implantation of biventricular support with HeartWare implantable continuous flow pump. ASAIO J 2011.57: 333–335.
6. Khani-Hanjani A, Loor G, Chamogeorgakis T, et al. Case series using the ROTAFLOW system as a temporary right ventricular assist device after HeartMate II implantation. ASAIO J 2013.59: 456–460.
7. Tran HA, Pollema TL, Silva Enciso J, et al. Durable biventricular support using right atrial placement of the heartWare HVAD. ASAIO J 2018.64: 323–327.