Outcomes of expanded polytetrafluoroethylene pericardial membrane implantation in left ventricular assist device explantation and heart transplantation.

Redo sternotomy and explantation of left ventricular assist devices (LVAD) for heart transplantation (HT) involve prolonged dissection, potential injury to mediastinal structures and/or bleeding. Our study compared a complete expanded polytetrafluoroethylene (ePTFE) wrap versus minimal or no ePTFE during LVAD implantation, on outcomes of subsequent HT. Between July 2005 and July 2018, 84 patients underwent a LVAD implant and later underwent HT. Thirty patients received a complete ePTFE wrap during LVAD implantation (Group 1), and 54 patients received either a sheet of ePTFE placed in the anterior mediastinum or no ePTFE (Group 2). Baseline characteristics were similar between Groups 1 and 2. Surgeons reported subjective improvements in speed, predictability, and safety of dissection with complete ePTFE compared with minimal or no ePTFE. Time from incision to initiation of cardiopulmonary bypass (CPB) were similar between groups (97 ± 38 vs. 89 ± 29 min, p = .3). Injury to mediastinal structures during the dissection was similar between groups (10% vs. 11%, p > .9). While surgeons reported less intraoperative bleeding in Group 1 (43% vs. 61%), this trend did not reach significance (p = .1). In-hospital mortality, intensive care unit length of stay and hospital length of stay were similar between both groups. In patients undergoing LVAD explant-HT, there was a trend toward reduced surgeon reported intraoperative bleeding with ePTFE placement. Despite qualitatively reported greater ease and speed of mediastinal dissection with ePTFE membrane placement, time to initiation of CPB did not differ, likely because surgeons remained cautious, allowing extra time for unanticipated difficulties.

An KR ，Christakis N ，Jegatheeswaran A ，Cusimano RJ ，Rao V ，Badiwala M ，Yau TM ... -  《-》

Expanded polytetrafluoroethylene membranes to wrap surfaces of circulatory support devices in patients undergoing bridge to heart transplantation.

OBJECTIVE:Because of a lack of donor hearts, an increasing number of patients with heart failure must now undergo bridge to cardiac transplantation with a mechanical circulatory support device. Moreover, support periods have become longer. As a result, pericardial adhesions may develop while the support device is implanted, increasing the risk of injury at resternotomy and bleeding after transplantation. Use of expanded polytetrafluoroethylene (ePTFE) pericardial substitutes (membranes) may prevent such adhesions. PATIENTS AND METHODS:From January 1997 to December 1999, ePTFE membranes were used in 23 patients to wrap portions of an implanted left ventricular assist device (LVAD) or total artificial heart (TAH). Any complications during mechanical support or at cardiac transplantation were recorded. Six ePTFE membranes removed at transplantation were studied histologically. RESULTS AND CONCLUSIONS:At resternotomy for transplantation, the plane of dissection between tissues, ePTFE membranes, and surfaces of the mechanical support device were easily discerned. No adhesions were observed between tissues and membranes. There were no injuries during resternotomy and no patient had to undergo reoperation because of bleeding. One patient given a TAH had an infection during circulatory support that was controlled by antibiotic therapy. In another patient, clots developed between the device and an ePTFE membrane; these were removed successfully. Histologic studies of removed ePTFE membranes showed no infiltration of the membranes interstices by collagen or cellular components. Use of ePTFE membranes in patients undergoing bridge to transplantation with either an LVAD or a TAH limited adhesions between tissues and device surfaces without increasing the risk of infection.

Leprince P ，Rahmati M ，Bonnet N ，Bors V ，Rama A ，Léger P ，Gandjbakhch I ，Pavie A ... -  《EUROPEAN JOURNAL OF CARDIO-THORACIC SURGERY》

Pericardial Closure With Expanded Polytetrafluoroethylene Patch in Left Ventricular Assist Device Surgery.

Meinert ÉFRC ，Kremer J ，Tochtermann U ，Sommer W ，Warnecke G ，Karck M ，Meyer AL ... -  《-》

Redo sternotomy versus left ventricular assist device explant as risk factors for early mortality following heart transplantation.

There is an increasing proportion of patients with a previous sternotomy (PS) or durable left ventricular assist device (LVAD) undergoing heart transplantation (HT). We hypothesized that patients with LVAD support at the time of HT have a lower risk than patients with PS and may have a comparable risk to patients with a virgin chest (VC). This is a single-centre retrospective cohort study of all adults who underwent primary single-organ HT between 2002 and 2017. Multivariable Cox regression analyses were performed to compare 30-day and 1-year mortality between transplanted patients with a VC (VC-HT), a PS (PS-HT) or an LVAD explant (LVAD-HT). Three hundred seventy-nine patients were analysed (VC-HT: 196, PS-HT: 94, LVAD-HT: 89). A larger proportion of patients in the LVAD-HT group were males (83%), had blood group O (52%), non-ischaemic aetiology (70%) and sensitization (67%). The PS-HT group had a higher frequency of patients with congenital heart disease (30%) and PSs compared to LVAD-HT patients (P < 0.001). PS-HT and LVAD-HT patients required a longer bypass time (P < 0.001) and showed a greater estimated blood loss (P < 0.001). Postoperatively, LVAD-HT required haemodialysis more frequently than the VC-HT group (P = 0.031). Multivariable analyses found that PS-HT patients had increased 30-day mortality compared to VC-HT [hazard ratio (HR) 2.63, 95% confidence interval (CI) 1.15-6.01; P = 0.022] while LVAD-HT did not (HR 2.17, 95% CI 0.96-4.93; P = 0.064). At 1-year, neither PS-HT nor LVAD-HT groups were significantly associated with increased mortality compared to VC-HT. Transplants in recipients with PS-HT demonstrated increased early mortality compared to VC-HT patients. Although LVAD explant is often technically challenging, this population demonstrated similar mortality compared to those VC-HT patients. The chronic and perioperative support provided by the LVAD may play a favourable role in early patient outcomes compared to other redo sternotomy patients.

Ribeiro RVP ，Alvarez JS ，Fukunaga N ，Yu F ，Adamson MB ，Foroutan F ，Cusimano RJ ，Yau T ，Ross H ，Alba AC ，Billia F ，Badiwala MV ，Rao V ... -  《-》

Prior Sternotomy and Ventricular Assist Device Implantation Do Not Adversely Impact Survival or Allograft Function After Heart Transplantation.

Orthotopic heart transplantation (OHT) remains the gold standard for end-stage heart failure. However, donor availability is severely limited. With a median wait time of 6.6 months and more than 12% of patients waiting 5 or more years, the decision is often made to implant a left ventricular assist device (LVAD) as a bridge to transplantation for medical stabilization. Furthermore, the number of patients who have had at least one prior sternotomy while awaiting transplantation is increasing. Previous studies have indicated reoperative sternotomy as a risk factor for compromised survival. Concerns are specifically focused on perioperative, short-term, and long-term outcomes after LVAD explantation or redo sternotomy before OHT because of increasing operative complexity. We hypothesize that despite the greater technical difficulty caused by LVAD explantation or redo sternotomy, outcomes would not be compromised. We retrospectively analyzed patients who underwent OHT at the University of Pennsylvania during a 5-year period (2008-2013; n = 253). All patients who underwent a bridge to transplantation LVAD (n = 72) or prior sternotomy (n = 65) were compared with those undergoing OHT with a virgin chest (n = 116). Preoperative, intraoperative, and postoperative variables were analyzed. Short- and long-term survival were studied (minimum follow-up, 6 months). Comorbidities were similar among the groups. There was no difference in donor allograft ischemic time (p = 0.6). However, cardiopulmonary bypass time was longer in both bridge to transplantation and prior sternotomy cohorts (p < 0.00001). The blood transfusion requirement was higher in bridge to transplantation (12.5 ± 13.7 units; p = 0.0007) and prior sternotomy groups (11.7 ± 12.9 units; p = 0.02) as compared with the virgin chest cohort (7.1 ± 10.7 units). For bridge to transplantation, both time to extubation (1.0 ± 1.6 versus 0.9 ± 1.0 days; p = 0.03) and intensive care unit length of stay (7.0 ± 7.0 versus 6.0 ± 7.0 days; p = 0.06) were longer compared with the virgin chest cohort. The same was true for prior sternotomy (extubation time, 1.9 ± 4.4 days; p = 0.005; intensive care unit length of stay, 8.0 ± 12.0 days; p = 0.06). There was no difference in hospital length of stay (p = 0.2). Overall, there was no difference in short- or long-term survival. Implantation of an LVAD as a bridge to transplantation or prior sternotomy does not adversely impact allograft function, hospital length of stay, or long-term outcomes after OHT. The decision to manage a patient medically while awaiting transplantation versus an LVAD bridge strategy should not be limited by concerns of subsequent poor outcomes after transplantation.

Gaffey AC ，Phillips EC ，Howard J ，Hung G ，Han J ，Emery R ，Goldberg L ，Acker MA ，Woo YJ ，Atluri P ... -  《-》