Faculty Bibliography

BACKGROUND: Diabetes mellitus (DM) is a risk factor for mortality among patients with heart failure as well as for patients who undergo cardiothoracic surgery. However it is unknown whether DM is associated with increased mortality or major complications during continuous-flow left ventricular assist device (CF-LVAD) support. METHODS AND RESULTS: We retrospectively reviewed 300 consecutive adults who received CF-LVADs at a single center in the years 2006-2013; 129 patients had DM before LVAD, as defined by American Diabetes Association criteria (HbA1c >/=6.5% and/or taking DM medications). Compared with the non-DM group, DM patients were older, with a higher pre-LVAD body mass index, more ischemic heart failure etiology, and higher pre-LVAD creatinine. Ninety-three patients died on LVAD support, 43 with DM and 50 without DM (P = .4526). After control for 9 covariates in a Cox proportional hazards model, DM was unassociated with all-cause mortality (hazard ratio 0.883, 95% confidence interval 0.571-1.366; P = .5768). Diabetes was also unassociated with the adverse event end points of stroke/transient ischemic attack, intracerebral hemorrhage, pump thrombosis, and device-related infections. CONCLUSIONS: Diabetes is common in LVAD recipients (43% of the present cohort) but does not increase mortality or rates of major adverse events during CF-LVAD support.

BACKGROUND: Data for left ventricular assist devices (LVADs) in patients with noninotrope-dependent heart failure (HF) are limited. OBJECTIVES: The goal of this study was to evaluate HeartMate II (HMII) LVAD support versus optimal medical management (OMM) in ambulatory New York Heart Association functional class IIIB/IV patients meeting indications for LVAD destination therapy but not dependent on intravenous inotropic support. METHODS: This was a prospective, multicenter (N = 41), observational study of 200 patients (97 LVAD, 103 OMM). Entry criteria included >/=1 hospitalization for HF in the last 12 months and 6-min walk distance (6MWD) <300 m. The primary composite endpoint was survival on original therapy with improvement in 6MWD >/=75 m at 12 months. RESULTS: LVAD patients were more severely ill, with more patients classified as Interagency Registry for Mechanically Assisted Circulatory Support profile 4 (65% LVAD vs. 34% OMM; p < 0.001) than 5 to 7. More LVAD patients met the primary endpoint (39% LVAD vs. 21% OMM; odds ratio: 2.4 [95% confidence interval: 1.2 to 4.8]; p = 0.012). On the basis of as-treated analysis, 12-month survival was greater for LVAD versus OMM (80 +/- 4% vs. 63 +/- 5%; p = 0.022) patients. Adverse events were higher in LVAD patients, at 1.89 events/patient-year (EPPY), primarily driven by bleeding (1.22 EPPY), than with OMM, at 0.83 EPPY, primarily driven by worsening HF (0.68 EPPY). Most patients (80% LVAD vs. 62% OMM; p < 0.001) required hospitalizations. Health-related quality of life (HRQol) and depression improved from baseline more significantly with LVADs than with OMM (Delta visual analog scale: 29 +/- 25 vs. 10 +/- 22 [p < 0.001]; Delta Patient Health Questionnaire-9: -5 +/- 7 vs. -1 +/- 5 [p < 0.001]). CONCLUSIONS: Survival with improved functional status was better with HMII LVAD compared with OMM. Despite experiencing more frequent adverse events, LVAD patients improved more in HRQol and depression. The results support HMII use in functionally limited, noninotrope-dependent HF patients with poor HRQoL. (Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device [LVAD] and Medical Management [ROADMAP]; NCT01452802).

BACKGROUND: Data from 3 institutions revealed an abrupt increase in HeartMate II (Thoratec) pump thrombosis starting in 2011, associated with 48% mortality at 6 months without transplantation or pump exchange. We sought to discover if the increase occurred nationwide in Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) data, and if so (1) determine if accelerated risk continued, (2) identify predictors, (3) investigate institutional variability, and (4) assess mortality after pump thrombosis. METHODS: From April 2008 to June 2014, 11,123 HeartMate II devices were implanted at 146 institutions. Machine learning, non-parametric Random Forests for Survival was used to explore risk-adjusted thrombosis based on 87 pre-implant and implant variables, including implant date. RESULTS: A total of 995 pumps thrombosed, with risk peaking within weeks of implant. The risk-adjusted increase in pump thrombosis began in 2010, reached a maximum in 2012, and then plateaued at a level that was 3.3-times higher than pre-2010. Pump exchange, younger age, and larger body mass index were important predictors, and institutional variability was largely explained by implant date, patient profile, and duration of support. The probability of death within 3 months after pump thrombosis was 24%. CONCLUSIONS: Accelerated risk of HeartMate II thrombosis was confirmed by Interagency Registry for Mechanically Assisted Circulatory Support data, with risk subsequently leveling at a risk-adjusted rate higher than observed pre-2010. This elevated thrombosis risk emphasizes the need for improved mechanical circulatory support systems and post-market surveillance of adverse events. Clinicians cognizant of these new data should incorporate them into their and their patients' expectations and understanding of risks relative to those of transplantation and continued medical therapy.

BACKGROUND: Left ventricular assist device (LVAD) infections including drivelines, pump pockets, and bacteremia are difficult to manage and conservative treatments may not be effective as the infected foreign material remains. METHODS: We performed a retrospective analysis of all 170 HeartMate II (Thoratec, Pleasanton, CA) implantations as bridge to transplant (BTT) between 2004 and 2012 at our institution. Sixty-one patients (36%) developed a culture positive driveline infection, pump pocket infection, bacteremia, or a combination of these. Twenty-six out of 61 patients with an infection and 49 out of 109 patients without an infection went on to receive a heart transplant. RESULTS: The 1- and 3-year freedom from LVAD infection was 60% and 32%, respectively. While early infection tends to first present as driveline infections, late infections tend to present initially as bacteremia. The 1-year likelihood of receiving a transplant in the patients with an LVAD infection group was 37%, compared with 43% in patients without an infection (p = 0.36). One-year survival to transplantation was 76% in patients with LVAD infection compared with 81% without (p = 0.33). The 1- and 3-year posttransplant survival in patients with a LVAD infection was 96% and 91%, respectively, compared with 92% and 88% in patients without an infection (p = 0.48) . CONCLUSIONS: In this nonmatched cohort of LVAD patients with and without infection, selected patients with controlled LVAD infection have an equal chance of getting transplanted with excellent early and late post-transplant survival.

BACKGROUND: Anticoagulation with warfarin is common in patients presenting for heart transplant. Prior to surgery, anticoagulation reversal is necessary to avoid significant intraoperative and perioperative bleeding complications. Commonly, warfarin reversal is achieved with vitamin K and fresh frozen plasma (FFP); however, these therapies have significant limitations. An alternative to FFP for reversal exists with prothrombin complex concentrate (PCC). A warfarin reversal protocol prior to heart transplant was implemented using low-dose PCC at our institution. OBJECTIVE: To assess blood product use, effectiveness, and safety post-low-dose PCC administration in patients needing warfarin reversal prior to heart transplant compared with historical controls. METHODS: This was a single-center, retrospective cohort study. The PCC cohort included patients undergoing heart transplant presenting with an international normalized ratio >/=1.5 on warfarin therapy and who received at least 1 dose of PCC. Blood product use was measured from postoperative day 0 to 2. RESULTS: The PCC and historical control cohorts included 16 and 50 patients, respectively. There was a significant reduction in the use of FFP (4 vs 8 units, P = 0.0239) in the PCC cohort compared with the historical control cohort. No differences were identified in the use of other blood products as well as other secondary efficacy or safety end points. CONCLUSIONS: Use of PCC, per the reversal protocol, prior to heart transplant reduced FFP use and showed a non-statistically significant trend toward reductions in the use of other blood products in the intraoperative and perioperative setting, with no difference identified in thrombotic or embolic complications compared with historical controls.