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The PREVENtion of HeartMate II pump Thrombosis through clinical management (PREVENT) study was a multicenter, prospective investigation to evaluate the rate of pump thrombosis (PT) with adoption of a uniform set of surgical and medical practices for left ventricular assist device implantation. We sought to quantify pump position at baseline and retrospectively define a pump position associated with poor clinical outcomes. Chest x-rays at baseline were prospectively obtained per protocol. Pump pocket depth, inflow cannula (IC) angle relative to the pump, and IC angle relative to the vertical were measured. Pumps falling in the tail-ends of the IC angle and pump pocket depth distributions were categorized as having an extreme pump position within the PREVENT study. Patients with extreme pump position had a significantly higher risk of confirmed and suspected PT, hemolysis, and elevated lactate dehydrogenase. In a multivariable analysis of survival free of confirmed PT, extreme pump position was an independent risk factor (hazard ratio = 3.6; 95% confidence interval = 1.5-8.9; p = 0.006) when adjusting for differences in pump speed and anticoagulation level. Our analysis shows that HeartMate II pump position at implant can significantly impact event-free survival and the incidence of adverse events at 6 months.

Background Patients with bleeding complications during left ventricular assist device (LVAD) support often require a reduction in the recommended warfarin plus aspirin regimen. To characterize those who can be safely managed with a reduced anti-thrombotic strategy, the TRACE (STudy of Reduced Anti-Coagulation/Anti-platelEt Therapy in Patients with the HeartMate II LVAS) study was initiated in the United States (U.S.) and Europe. Methods The TRACE U.S. arm enrolled HeartMate II (HMII; Thoratec) outpatients on a regimen of reduced anti-thrombotic therapy (RT), defined as vitamin K antagonist (warfarin) only, aspirin only, or no anti-thrombotic agent. The indication for RT, changes in anti-thrombotic therapies, and patient outcomes after RT were documented. Results for patients reaching 12 months or outcome are presented here. Results Between April 2012 and June 2013, 100 HMII outpatients (85% men) on RT (median age 64.5 [interquartile range, 32, 82] years, 61% with ischemic etiology, 69% destination therapy) were enrolled from 9 U.S. sites. The primary reason for RT initiation was in response to a bleeding event (82%). Pharmacotherapy at RT initiation included warfarin only (38%), aspirin only (28%), or no anti-thrombotic agent (34%). Freedom from ischemic stroke at 1 year was 93.8% ± 2.5%, and freedom from device thrombosis was 92.7% ± 2.7%. Despite RT, a subsequent bleeding event occurred in 52%. Conclusions Reducing anti-thrombotic therapies in response to bleeding among HMII patients was achievable but may be associated with a higher risk for device thrombosis. Furthermore, despite an RT strategy, bleeding often will persist in those prone to such events.

Introduction and hypothesis: Recent data have indicated an increase in the rate of early, confirmed pump thrombosis of the HeartMate II (HMII) left ventricular assist device. Factors related to this increase were not known, but one of the hypotheses was change in clinical management over time. The PREVENT ( PREVEN tion of Heartmate II Pump T hrombosis through Clinical Management) study was designed to evaluate the impact of clinical practices developed to reduce the risk of HMII pump thrombosis. Methods: PREVENT is a prospective, multi-center, single-arm, non-randomized study of up to 300 patients at up to 25 sites. Patient and pump management, including implant technique, anticoagulation, and pump settings are guided by protocol (Table 1). Primary endpoint is incidence of confirmed pump thrombosis at 3 months, with a total follow-up of 6 months. Presented here are the preliminary results from the first 100 subjects enrolled. Results: Median age was 61 years [25-79], 87% were male, and 79% were destination therapy. At implant, 9% were in INTERMACS Profile1, 68% Profiles 2-3, and 22% Profiles 4-7. Preliminary analysis of 90-day outcomes demonstrated an incidence of 1% for confirmed and 2% for suspected thrombosis with a 38% incidence of INTERMACS-defined bleeding. Adherence to the protocol recommendations was as follows: 91% of the pumps were anchored, 97% of the patients were bridged with heparin, median pump speed at 1 month was 9190 [range: 8400-10000], with 93% of the patients having a pump speed > 8600, and 78% of the patients having pump speeds > 9000. Median INR per patient was 2.2 [IQR: 2.0-2.4]. Overall Kaplan-Meier survival was 93%. Conclusions: Preliminary results are encouraging and suggest good adherence to the PREVENT protocol and low rates of pump thrombosis without a resultant increase in bleeding complications. Overall survival after HM II implantation remains excellent.

The aim of this study was to derive and validate a model to predict survival in candidates for HeartMate II (HMII) (Thoratec, Pleasanton, California) left ventricular assist device (LVAD) support.LVAD mortality risk prediction is important for candidate selection and communicating expectations to patients and clinicians. With the evolution of LVAD support, prior risk prediction models have become less valid.Patients enrolled into the HMII bridge to transplantation and destination therapy trials (N = 1,122) were randomly divided into derivation (DC) (n = 583) and validation cohorts (VC) (n = 539). Pre-operative candidate predictors of 90-day mortality were examined in the DC with logistic regression, from which the HMII Risk Score (HMRS) was derived. The HMRS was then applied to the VC.There were 149 (13%) deaths within 90 days. In the DC, mortality (n = 80) was higher in older patients (odds ratio [OR]: 1.3, 95% confidence interval [CI]: 1.1 to 1.7 per 10 years), those with greater hypoalbuminemia (OR: 0.49, 95% CI: 0.31 to 0.76 per mg/dl of albumin), renal dysfunction (OR: 2.1, 95% CI: 1.4 to 3.2 per mg/dl creatinine), coagulopathy (OR: 3.1, 95% CI: 1.7 to 5.8 per international normalized ratio unit), and in those receiving LVAD support at less experienced centers (OR: 2.2, 95% CI: 1.2 to 4.4 for15 trial patients). Mortality in the DC low, medium, and high HMRS groups was 4%, 16%, and 29%, respectively (p0.001). In the VC, corresponding mortality was 8%, 11%, and 25%, respectively (p0.001). HMRS discrimination was good (area under the receiver-operating characteristic curve: 0.71, 95% CI: 0.66 to 0.75).The HMRS might be useful for mortality risk stratification in HMII candidates and may serve as an additional tool in the patient selection process.

Background: Health status predicts death and hospitalization in heart failure and cardiac surgery, but its prognostic value in the setting of left ventricular assist device (LVAD) placement is unknown. We hypothesized that baseline health status could help identify patients at risk for adverse post-operative outcomes and improve patient selection for LVAD therapy. Methods: We examined the association of pre-operative health status, as measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary score (OSS), with overall mortality and hospitalization in 965 patients undergoing LVAD placement as part of two clinical trials of the HeartMate II device. Unadjusted statistical analyses were performed using Cox proportional hazard models and Kruskal-Wallis non-parametric tests. Results: Baseline OSS of survivors (median: 25.5, inter quartile range (IQR): 15.6-38.6) was similar to those who died (median: 23.4, IQR 12.9-39.2, p=0.06). Patients in the lowest quartile of KCCQ scores (OSS Conclusion: Only patients with very low baseline health status (KCCQ