Acute kidney injury after implantation of a left ventricular assist device: a comparison of axial-flow (HeartMate II) and centrifugal-flow (HeartWare HVAD) devices.

Continuous-flow left ventricular assist devices (CF-LVADs) are increasingly being used to treat advanced, refractory chronic heart failure. Herein, we sought to determine the incidence of postoperative acute kidney injury (AKI) in axial-flow (HeartMate II; HM-II) and centrifugal-flow (HVAD) CF-LVAD recipients, as well as the effect of AKI on mortality. The study cohort comprised 520 patients who received a HM-II (n = 398) or HVAD (n = 122) at our center between November 2003 and March 2016. Their records were reviewed to determine the incidence of RIFLE-defined AKI after LVAD implantation. We compared the perioperative characteristics, postoperative complications, and survival rates of the patients with and without AKI and differentiated the outcomes based on device type (HM-II or HVAD). Seventy-five patients (14.4%) developed AKI postoperatively. Patients with AKI after LVAD implantation had significantly reduced survival compared to patients without AKI (p = 0.01). Cox proportional hazards models showed that AKI was a significant independent predictor of mortality (HR = 1.54, p = 0.03). Preoperative mechanical circulatory support and prolonged cardiopulmonary bypass time were independent predictors of AKI. The incidence of AKI was similar for HM-II and HVAD recipients (p = 0.25). There was no significant difference in AKI rates for the HM-II and HVAD recipients. Developing AKI adversely affected survival.

HeartMate II left ventricular assist device implantation in patients with advanced hepatic dysfunction.

BACKGROUND: We sought to determine the outcomes for patients with advanced hepatic dysfunction undergoing HeartMate II left ventricular assist device (LVAD) implantation. METHODS: Between November 1, 2003 and December 1, 2012, we implanted the HeartMate II continuous-flow LVAD in 338 patients, either for bridging to heart transplantation or for destination therapy. Twenty-three of these patients (19 men and 4 women; mean age, 47 ± 16 years) had advanced hepatic dysfunction, as characterized by alanine aminotransferase (ALT) or aspartate transaminase (AST) levels five times normal; serum total bilirubin levels three times normal; and/or necessity for a liver biopsy before or during device implantation. Of this group, 17 patients received the LVAD as a bridge to transplantation, and six patients received it for destination therapy. RESULTS: Nine of the 23 patients required either a transjugular or a core liver biopsy during LVAD implantation. Three patients died within the first postoperative month; the 20 surviving patients had significant improvements in their hepatic parameters. The ALT decreased from 238 ± 296 to 27 ± 13 U/L (p = 0.022), AST decreased from 209 ± 199 to 29 ± 8 U/L (p = 0.009), and total bilirubin level decreased from 6.9 ± 6.0 to 0.6 ± 0.1 mg/dL (p = 0.044). The serum albumin level increased from 3.2 ± 0.6 to 4.3 ± 0.3 g/dL (p = 0.003), and creatinine clearance increased from 77.6 ± 35.2 to 110.2 ± 35.7 mL/min/1.73 m2 (p = 0.101). CONCLUSION: Continuous-flow LVAD support may significantly improve hepatic function, allowing patients with poor preimplant liver function to become better candidates for heart transplantation.

Survival on the Heart Transplant Waiting List.

Importance: With continuing improvements in medical devices and more than a decade since the 2006 United Network for Organ Sharing (UNOS) allocation policy, it is pertinent to assess survival among patients on the heart transplantation waiting list, especially given the recently approved 2018 UNOS allocation policy. Objectives: To assess survival outcomes among patients on the heart transplant waiting list during the past 3 decades and to examine the association of ventricular assist devices (VADs) and the 2006 UNOS allocation policy with survival. Design, Setting, and Participants: A retrospective cross-sectional used the UNOS database to perform an analysis of 95 323 candidates wait-listed for heart transplantation between January 1, 1987, and December 29, 2017. Candidates for all types of combined transplants were excluded (n = 2087). Patients were followed up from the time of listing to death, transplantation, or removal from the list due to clinical improvement. Competing-risk, Kaplan-Meier, and multivariable Cox proportional hazards regression analyses were used. Main Outcomes and Measures: The analysis involved an unadjusted and adjusted survival analysis in which the primary outcome was death on the waiting list. Because of changing waiting list preferences and policies during the study period, the intrinsic risk of death for wait-listed candidates was assessed by individually analyzing, comparing, and adjusting for several candidate risk factors. Results: In total, 95 323 candidates (72 915 men [76.5%]; mean [SD] age, 51.9 [12.0] years) were studied. In the setting of changes in listing preferences, 1-year survival on the waiting list increased from 34.1% in 1987-1990 to 67.8% in 2011-2017 (difference in proportions, 0.34%; 95% CI, 0.32%-0.36%; P < .001). The 1-year waiting list survival for candidates with VADs increased from 10.2% in 1996-2000 to 70.0% in 2011-2017 (difference in proportions, 0.60%; 95% CI, 0.58%-0.62%; P < .001). Similarly, in the setting of changing mechanical circulatory support indications, the 1-year waiting list survival for patients without VADs increased from 53.9% in 1996-2000 to 66.5% in 2011-2017 (difference in proportions, 0.13%; 95% CI, 0.12%-0.14%; P < .001). In the decade prior to the 2006 UNOS allocation policy, the 1-year waiting list survival was 51.1%, while in the decade after it was 63.9% (difference in proportions, 0.13%; 95% CI, 0.12%-0.14%; P < .001). In adjusted analysis, each time period after 1987-1990 had a marked decrease in waiting list mortality. Conclusions and Relevance: This study found temporally associated increases in heart transplant waiting list survival for all patient groups (with or without VADs, UNOS status 1 and status 2 candidates, and candidates with poor functional status).

Histologic findings proving the existence of humoral rejection in a cardiac allograft.

Humoral rejection (HR) of the cardiac allograft is neither well characterized nor universally recognized in the transplant/pathology-related literature. One reason for this is that the histologic light-microscopic features are inconsistent, making HR difficult to recognize in the majority of cases. We report an unusual case of cardiac allograft rejection in a patient with a complicated postoperative course who ultimately died within 6 months of transplant. Premortem, HR was not diagnosed in multiple cardiac biopsies. The autopsy revealed unequivocal histologic and immunohistochemical evidence of HR. Vascular distension and endocardial infiltration by numerous macrophages were noted only in the cardiac allograft and were notably absent in the native tissue present within the anastomotic sites. There was capillary deposition of immunoglobulin and complement shown by immunofluorescence staining of frozen tissue, and there was diffuse immunohistochemical staining for C4d within the intramyocardial vessels. This case appears to represent an exaggerated antibody-mediated rejection of the cardiac allograft.

Results of HeartMate II left ventricular assist device implantation on renal function in patients requiring post-implant renal replacement therapy.

BACKGROUND: Renal function is often compromised in patients with advanced heart failure. METHODS: We evaluated renal function in heart failure patients supported by the HeartMate II (Thoratec Corporation, Pleasanton, CA) continuous-flow left ventricular assist device (LVAD) who required renal replacement therapy (RRT) by continuous venovenous hemofiltration dialysis (CVVHD) or hemodialysis, or both. Indications for RRT included oliguria (urine < 400 ml/day) unresponsive to diuretic therapy for > 24 hours with a creatinine level > 2.0 mg/dl or 1.5 times that of the pre-implant creatinine level, severe acidemia, and volume overload. RESULTS: Of 107 consecutive patients who underwent HeartMate II implantation at our center and had been supported for > 30 days, 15 (13 men and 2 women) required post-implant RRT. Of the 15 patients, 3 received CVVHD and 12 received CVVHD and hemodialysis. Renal function improved within 2 months of support compared with average values before support (creatinine clearance, 64 ± 39 vs 92 ± 55 ml/min, p = 0.041; glomerular filtration rate, 46.9 ± 20.7 vs 73.2 ± 38.9 ml/min/1.73 m(2); p = 0.032). Renal function improved after HeartMate II implantation in 10 patients, and RRT was removed. Of these 10 patients, 2 underwent heart transplantation 4 months after RRT was removed, 1 underwent heart and kidney transplantation 4 years later, 2 died at home of conditions unrelated to renal function 6 months after RRT was removed, and 5 are awaiting heart transplantation, with good quality of life. CONCLUSIONS: In this study, patients who experienced clinical recovery after the LVAD implant had subsequent recovery of renal function after continuous-flow LVAD support.