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Background: Although left ventricular assist device (LVAD) management strategies are undertaken to reduce the development of aortic insufficiency (AI), the effect of AI on patient morbidity and mortality is not known., Methods: Patients undergoing HeartMate II (Thoratec, Pleasanton, CA) implant were prospectively monitored with serial echocardiograms. Kaplan-Meier methods and log-rank testing were used to estimate and compare mortality and freedom from moderate or worser right ventricular hypokinesis (RVHK), moderate or worse mitral regurgitation (MR), and hemolysis according to AI severity. Mixed modelling was used to examine for correlates of AI development in the pre-operative and post-operative setting and to investigate the effect of AI on post-operative MR and RVHK., Results: There were 930 echocardiograms completed in 166 patients. During 291 person-years of follow-up, mild-moderate or worse AI developed in 70 (0.38 persons per year [PPY]), moderate or worse AI in 36 (0.17 PPY), moderate-severe AI in 11 (0.039 PPY), and severe AI in 2 (0.0069 PPY). Overall 2-year survival and 2-year survival after onset of moderate or worse AI was 87% ± 6.2% and 65% ± 11%, respectively, compared with 76% ± 5.1% and 76% ± 5.1%, respectively, in those with less AI (p = 0.57). Patients with moderate AI were not more likely to develop MR, hemolysis events, or worsening RVHK, but patients with pre-existing RVHK appeared to be less tolerant of AI. Three of 35 deaths were directly attributed to AI. No reoperations were performed solely for AI., Conclusions: AI is common after LVAD implant but did not affect survival in this cohort. Except in those with significant RV dysfunction, this calls into question need for echocardiogram-guided device settings to ensure aortic valve opening., (Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Background: The clinical relevance of elevated serum markers of hemolysis during left ventricular assist device (LVAD) support has not been fully ascertained., Methods: Lactate dehydrogenase (LDH) and serum free hemoglobin (sfHg) values were tallied monthly in 182 patients on HeartMate II (Thoratec, Pleasanton, CA) LVAD support. Peak values for each marker were identified, and 2 hemolysis definitions were applied to the cohort: Hemolysis according to Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) criteria (sfHg > 40 mg/dl with signs/symptoms) and/or hemolysis defined by an LDH ≥ 600 IU/liter (2.5-times the upper limit of laboratory normal). Kaplan-Meier survival free from death, urgent United Network of Organ Sharing 1A transplant for thrombosis, device exchange for thrombosis, and stroke/peripheral embolism was estimated, and Cox hazard ratios (HR) with the 95% confidence interval (95% CI) were calculated. Areas under the receiver-operating characteristic curves (AUCs) for predicting 1-year event-free survival were calculated., Results: Hemolysis occurred in 32 patients (18%) by INTERMACS criteria and in 68 (37%) patients by LDH criteria. Over a median (25(th), 75(th)) support of 427 days (245, 793 days), there were 78 events. One year event-free survival after the onset of INTERMACS-defined hemolysis was 16% ± 8.3% compared with 85% ± 3.2% in non-hemolyzers (HR, 14.7; 95% CI, 7.9-27; AUC 0.70 ± 0.05; p < 0.001; ). One year event-free survival after the onset of LDH-defined hemolysis was 32% ± 7.2% compared with 89% ± 3.2% in those with persistent LDH values < 600 IU/liter (HR, 8.0; 95% CI, 4.4-14; AUC 0.87 ± 0.04; p < 0.001). Patients who met the LDH hemolysis definition had longer times from hemolysis onset to clinical events and larger magnitudes of risk for embolism and device exchange for thrombosis than those with INTERMACS hemolysis., Conclusions: Serum hemolysis marker elevations are associated with increased events in LVAD patients. LDH monitoring provides an earlier diagnosis of adverse events than sfHg, supporting need for a new INTERMACS definition of VAD-associated hemolysis., (© 2014 International Society for Heart and Lung Transplantation Published by International Society for the Heart and Lung Transplantation All rights reserved.)

Background: Modern left ventricular assist devices (LVAD) require anti-coagulation (AC) with warfarin and anti-platelet therapy to prevent thromboembolic complications in patients. Gastrointestinal bleeding (GI) is a significant adverse event in these patients and treatment typically requires reduction or elimination of AC or anti-platelet therapy. It is not known whether alterations in AC to treat GI bleeding influence subsequent risk of thromboembolic (TE) events during LVAD support., Methods: Between July 2003 and September 2011, 389 patients (308 male) underwent implantation of a continuous-flow LVAD at the University of Michigan Health System and the Mayo Clinic. Median age at implant was 60 years (range 18 to 79 years). Outcomes were analyzed for the association of GI bleeding events and subsequent TE events, defined as stroke, transient ischemic attack, hemolysis or suspected or confirmed pump thrombosis., Results: Median survival was 10 months (maximum 7.2 years, total 439 patient-years). TE events occurring within the first 30 days were not counted. Overall survival and freedom from an outcome event were assessed using the Kaplan-Meier method. Associations between GI bleeding and subsequent TE events and survival impact were analyzed as time-dependent covariates. One hundred ninety-nine GI bleeding episodes occurred in 116 of 389 patients (30%) for an event rate of 0.45 GI bleed/patient-year of support. One hundred thirty-eight TE events occurred in 97 of 389 patients (25%) for an event rate of 0.31 TE event/patient-year of support. Median time from LVAD implant to first GI bleed was 5 months (range 1 to 116 months) and to first TE event was 6 months (range 1 to 29 months). For patients who had a TE event after GI bleed, the median interval was 5 months (range 0.5 to 25 months). TE events were 7.4-fold more likely in patients who had a prior GI bleed (range 4.9- to 11.1-fold) (p < 0.001); however, neither the presence of GI bleeding (0.7 to 1.2) nor a TE event (0.8 to 2.0) portended a lower overall survival., Conclusions: Patients who had GI bleeding were at significantly higher risk for a subsequent TE event. Although the exact cause of this relationship is unknown, it suggests that a reduction in anti-coagulation and anti-platelet management to treat GI bleeds may contribute to this risk., (Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Background: Delayed sternal closure (DSC) is employed after conventional cardiac surgery without a significantly increased risk of late mediastinitis or sternal wound infection. There are no data specifically examining its late effects on patients undergoing implantation with a ventricular assist device (VAD)., Methods: Between October 1996 and October 2010, 364 patients underwent primary VAD implant and DSC was utilized in 184 (51%) patients for coagulopathy (n = 155; 84%), hemodynamic instability (n = 103; 56%), isolated right ventricular dysfunction (n = 15; 8%) or unspecified reasons (n = 17; 9%)., Results: Median duration of DSC was 1 day (range 1 to 7 days). Patients with DSC were older (54.5 vs. 50.3 years, p = 0.002), had a higher incidence of previous sternotomy (42% vs. 28%, p = 0.005), pre-operative intra-aortic balloon pump (50% vs. 30%, p < 0.001), pre-operative temporary extracorporeal mechanical circulatory support (23% vs 10%, p < 0.001), lower platelet counts (171,000 vs. 209,000, p < 0.001) and lower hematocrit levels (32% vs. 36%, p < 0.001). Operative (11% vs. 9%, p = 0.65) or late (2 years; 66 ± 7% vs 66 ± 7%, p = 0.720) mortality; composite incidence of mediastinitis, percutaneous drive-line infection, pocket infection and VAD-related endocarditis (15% vs. 16%, p = 0.79); re-exploration for bleeding (18% vs. 18%, p = 0.99); urgent transplantation for infection (4% vs. 3%, p = 0.99); or need for device exchange (9% vs. 10%, p = 0.16) was not increased after DSC when compared with immediate sternal closure. DSC increased ICU stay (10 vs. 5 days, p = 0.001)., Conclusions: DSC was performed most commonly for coagulopathy and/or hemodynamic instability, and patients were older with a greater severity of illness as shown by the higher incidence of right-sided circulatory failure and history of prior sternotomy. Although DSC was associated with longer ICU stay, DSC was not associated with a significantly increased risk of death or infection., (Copyright © 2012 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)