Low-molecular-weight heparin for anti-coagulation after left ventricular assist device implantation.

BACKGROUND: Anti-coagulation is required in patients with left ventricular assist devices (LVADs). We evaluated the feasibility of low-molecular-weight heparin (LMWH) for initiation of anti-coagulation and transitioning to oral anti-coagulation after LVAD implantation. METHODS: This single-center study included 78 consecutive patients who underwent either Thoratec HeartMate II LVAD (n = 27) or HeartWare ventricular assist device (HVAD, n = 51) implantation. The LMWHs enoxaparin (n = 50) and dalteparin (n = 28) were used. LMWH was started within 24 hours post-operatively in 79.5% of patients. No anti-coagulation was given before starting LMWH therapy. LMWH activity was monitored by determination of anti-factor Xa levels in plasma. RESULTS: The majority of patients (80.7%) had peak anti-Xa activity within the defined range of efficacy of 0.2 to 0.4 IU/ml by the second day of treatment. Mean effective peak anti-Xa activity was 0.28 ± 0.06 IU/ml. Mean duration of anti-coagulation with LMWH was 25.8 ± 18 days. Ischemic strokes were observed in 3 patients (3.8%), with a total of 4 events. Three events occurred while on LMWH, and 1 event occurred during follow-up on oral anti-coagulation. There was 1 fatal stroke. No pump thrombus was observed. Major bleeding was observed in 5 patients (6.4%), with a total of 6 events. Gastrointestinal bleeding was the most common complication (n = 3). There were no fatal bleeding events. CONCLUSIONS: LMWH in the setting of LVAD shows rapid and constant biologic efficacy. Anti-coagulation with LMWH appears feasible after LVAD implantation. These findings support further evaluation of LMWH as an alternative to unfractionated heparin in this patient cohort.

Results of the post-market Registry to Evaluate the HeartWare Left Ventricular Assist System (ReVOLVE).

BACKGROUND: The post-market Registry to Evaluate the HeartWare Left Ventricular Assist System (ReVOLVE) is an investigator-initiated registry established to collect post-CE Mark Trial clinical data on patients receiving a HeartWare ventricular assist device (HVAD) in the European Union and Australia. METHODS: The ReVOLVE is a multi-center, prospective, single-arm registry performed at seven centers in Europe and two in Australia. Herein we describe a total of 254 commercial HVAD implants according to labeled indications between February 2009 and November 2012. Summary statistics included patients' demographics, adverse events, length of support and outcomes. RESULTS: Compared with the clinical trial supporting the CE Mark of the HeartWare system, patient selection differed in that patients were older, and there were higher proportions of females and patients with idiopathic cardiomyopathies in the ReVOLVE cohort. Duration of support ranged from 1 to 1,057 days, with a mean of 363 ± 280 days (median 299.5 days). Transplantation was done in 56 patients (22%), explant for recovery was performed in 3 patients (1%), 43 died while on support (17%), and 152 (60%) remain on the device. Success in patients with the HeartWare system was 87% at 6 months, 85% at 1 year, 79% at 2 years and 73% at 3 years. Adverse event rates were low, comparable or improved when compared to the CE Mark Trial. CONCLUSION: Real-world use of the HeartWare system continues to demonstrate excellent clinical outcomes in patients supported with the device.

Cardiogenic shock in ACS. Part 2: Role of mechanical circulatory support.

This Review explores contemporary circulatory support in profound postinfarction cardiogenic shock. Frequently, death is the only alternative to implantation of a blood pump, so prospective randomized trials of device versus medical treatment are unacceptable and evidence is derived from clinical experience. Irrespective of ACC/AHA and European guidelines, no study has shown survival benefit for the intra-aortic balloon pump in patients with established shock. In the past 10 years, the safety and durability of mechanical blood pumps has improved considerably. New temporary and long-term rotary pumps have transformed outcomes for patients with acute heart failure. For urgent resuscitation, outreach salvage, and transportation extracorporeal membrane oxygenation (ECMO) is a reliable, but time limited, first step. ECMO decompresses the venous system, provides flow, and ensures oxygenation, but does not unload the failing left ventricle. Myocardial stunning takes days, and sometimes weeks, to recover. Effective ventricular unloading is best achieved by surgical implantation of a temporary rotary or volume-displacement pump. After cardiopulmonary resuscitation, hemodynamic stabilization allows assessment of cerebral injury and prognosis. Published series demonstrate that 50-75% of patients with profound shock can be salvaged either through native heart recovery, urgent transplantation, or switch to a long-term pump.

Multicenter evaluation of an intrapericardial left ventricular assist system.

OBJECTIVES: The aim of this study was to conduct an initial clinical evaluation of the new HeartWare Ventricular Assist System (HeartWare, Inc., Framingham, Massachusetts) in a multicenter, prospective, nonrandomized single-arm clinical trial. BACKGROUND: Heart failure is a worldwide epidemic. The effectiveness of heart transplantation and medical therapy is limited, resulting in the emergence of mechanical circulatory support as a primary treatment for end-stage heart disease. Left ventricular assist devices that use rotary pumps are small and durable, which might reduce morbidity and mortality during support. METHODS: Fifty heart transplant candidates with New York Heart Association functional class IV symptoms were supported at 5 international centers by the HeartWare System for 180 days, until heart transplant, myocardial recovery and device explant, or death. Patients who continue to be supported have been followed for a minimum of 2 years. RESULTS: Of the 50 patients, 20 (40%) received transplants, 4 (8%) had the pump explanted after myocardial recovery, and 17 (34%) continue support at 2 years. Nine (18%) patients died during support from sepsis (n = 3), multiple organ failure (n = 3), or hemorrhagic stroke (n = 3). The actual survival at 6, 12, and 24 months was 90%, 84%, and 79%, respectively. In the survivors, measures of quality of life showed a significant improvement over baseline values. Significant improvements were found for recognition memory at 3 months after implant (p = 0.006). The most frequent adverse events were infection and bleeding. CONCLUSIONS: Patients with end-stage heart failure can be safely and effectively supported by the HeartWare Ventricular Assist System with improved quality of life and neurocognitive function.