Long-term follow-up of continuous flow left ventricular assist devices: complications and predisposing risk factors.

PURPOSE: To assess LVAD complications and their overall effect on mortality and determine factors associated with development of early and long-term complications. METHODS: A retrospective cohort study of patients who underwent continuous flow LVAD placement between January 1, 2000 and November 30, 2013 was performed. The incidence of complications (sepsis or bacteremia, driveline infections, gastrointestinal bleeding, pump thrombosis, cerebrovascular accidents and anemia requiring transfusion) was collected and logistic regression and Cox proportional hazards analyses were performed. RESULTS: 108 patients met our inclusion criteria. Median length of follow-up was 2.2 years. In univariable logistic regression analysis, higher blood urea nitrogen (BUN), creatinine clearance <60, no prior inotrope use, higher INTERMACS class and lower platelet count were associated with early complications. On multivariable analysis, factors associated with early complications included higher BUN (odds ratio (OR) 1.03, 95% confidence interval (CI) 1.001-1.06 per mg/dL BUN), no prior inotrope use (OR 4.92, 95% CI 1.64- 14.7) and lower platelet count (OR 4.29, 95% CI 1.45-12.7 <200 10(3) cu mm); 24% of patients developed early complications and 18.5% developed an early and late complication. Early complications were significantly associated with death (p = 0.017). The presence of 2 or more complications was associated with a 2.7-fold increase in the odds of death (p = 0.016) and odds of death increased by 20% with each subsequent complication (p = 0.004). CONCLUSIONS: LVADs are associated with significant long-term complications including stroke and sepsis and minimizing time on LVADs may decrease the risk of complications and subsequent morbidity and mortality.

Angiotensin II antagonism is associated with reduced risk for gastrointestinal bleeding caused by arteriovenous malformations in patients with left ventricular assist devices.

BACKGROUND: Angiogenesis is implicated in formation of gastrointestinal arteriovenous malformations (AVMs). Angiotensin II signaling is involved in angiogenesis through the vascular endothelial growth factor (VEGF) and angiopoietin-2 pathways. We hypothesized that angiotensin-converting enzyme inhibitor (ACEI) and angiotensin receptor blocker (ARB) therapy would be associated with a reduced risk of all-cause gastrointestinal bleeding (GIB) and AVM-associated GIB in patients with left ventricular assist devices (LVADs). METHODS: We reviewed records of all adult patients receiving a continuous-flow LVAD (HeartMate II or HeartWare HVAD) at Johns Hopkins Hospital between January 2004 and December 2014. Of 192 patients, 131 were included for final analyses. Logistic regression analysis adjusting for demographic, cardiovascular, and laboratory variables was used to assess the association of ACEI or ARB therapy with GIB. RESULTS: Of 131 patients, 100 received ACEI or ARB therapy during LVAD support. Of the 31 patients who did not receive ACEI or ARB, 15 experienced GIB (48%), with 9 caused by AVMs (29%). Of 100 patients who received ACEI or ARB therapy, 24 experienced GIB (24%), with 9 caused by AVMs (9%). Logistic regression hazards model demonstrated that ACEI or ARB therapy was independently associated with a reduced risk for all-cause GIB (odds ratio 0.29, 95% confidence interval 0.12-0.72) and AVM-related GIB (odds ratio 0.23, 95% confidence interval 0.07-0.71). CONCLUSIONS: Angiotensin II antagonism is associated with a reduced risk of AVM-related GIB in patients with LVADs. This association is independent of age, sex, blood pressure, renal function, international normalized ratio, LVAD type, and cardiomyopathy etiology.

Right ventricular afterload sensitivity dramatically increases after left ventricular assist device implantation: A multi-center hemodynamic analysis.

BACKGROUND: Right ventricular (RV) failure is a source of morbidity and mortality after left ventricular assist device (LVAD) implantation. In this study we sought to define hemodynamic changes in afterload and RV adaptation to afterload both early after implantation and with prolonged LVAD support. METHODS: We reviewed right heart catheterization (RHC) data from participants who underwent continuous-flow LVAD implantation at our institutions (n = 244), excluding those on inotropic or vasopressor agents, pulmonary vasodilators or additional mechanical support at any RHC assessment. Hemodynamic data were assessed at 5 time intervals: (1) pre-LVAD (within 6 months); (2) early post-LVAD (0 to 6 months); (3) 7 to 12 months; (4) 13 to 18 months; and (5) very late post-LVAD (18 to 36 months). RESULTS: Sixty participants met the inclusion criteria. All measures of right ventricular load (effective arterial elastance, pulmonary vascular compliance and pulmonary vascular resistance) improved between the pre- and early post-LVAD time periods. Despite decreasing load and pulmonary artery wedge pressure (PAWP), RAP remained unchanged and the RAP:PAWP ratio worsened early post-LVAD (0.44 [0.38, 0.63] vs 0.77 [0.59, 1.0], p < 0.001), suggesting a worsening of RV adaptation to load. With continued LVAD support, both RV load and RAP:PAWP decreased in a steep, linear and dependent manner. CONCLUSIONS: Despite reducing RV load, LVAD implantation leads to worsened RV adaptation. With continued LVAD support, both RV afterload and RV adaptation improve, and their relationship remains constant over time post-LVAD. These findings suggest the RV afterload sensitivity increases after LVAD implantation, which has major clinical implications for patients struggling with RV failure.