RESUMEN
BACKGROUND: In an early analysis of this trial, use of a magnetically levitated centrifugal continuous-flow circulatory pump was found to improve clinical outcomes, as compared with a mechanical-bearing axial continuous-flow pump, at 6 months in patients with advanced heart failure. METHODS: In a randomized noninferiority and superiority trial, we compared the centrifugal-flow pump with the axial-flow pump in patients with advanced heart failure, irrespective of the intended goal of support (bridge to transplantation or destination therapy). The composite primary end point was survival at 2 years free of disabling stroke (with disabling stroke indicated by a modified Rankin score of >3; scores range from 0 to 6, with higher scores indicating more severe disability) or survival free of reoperation to replace or remove a malfunctioning device. The noninferiority margin for the risk difference (centrifugal-flow pump group minus axial-flow pump group) was -10 percentage points. RESULTS: Of 366 patients, 190 were assigned to the centrifugal-flow pump group and 176 to the axial-flow pump group. In the intention-to-treat population, the primary end point occurred in 151 patients (79.5%) in the centrifugal-flow pump group, as compared with 106 (60.2%) in the axial-flow pump group (absolute difference, 19.2 percentage points; 95% lower confidence boundary, 9.8 percentage points [P<0.001 for noninferiority]; hazard ratio, 0.46; 95% confidence interval [CI], 0.31 to 0.69 [P<0.001 for superiority]). Reoperation for pump malfunction was less frequent in the centrifugal-flow pump group than in the axial-flow pump group (3 patients [1.6%] vs. 30 patients [17.0%]; hazard ratio, 0.08; 95% CI, 0.03 to 0.27; P<0.001). The rates of death and disabling stroke were similar in the two groups, but the overall rate of stroke was lower in the centrifugal-flow pump group than in the axial-flow pump group (10.1% vs. 19.2%; hazard ratio, 0.47; 95% CI, 0.27 to 0.84, P=0.02). CONCLUSIONS: In patients with advanced heart failure, a fully magnetically levitated centrifugal-flow pump was superior to a mechanical-bearing axial-flow pump with regard to survival free of disabling stroke or reoperation to replace or remove a malfunctioning device. (Funded by Abbott; MOMENTUM 3 ClinicalTrials.gov number, NCT02224755 .).
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Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Diseño de Prótesis , Adulto , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Femenino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Corazón Auxiliar/efectos adversos , Humanos , Análisis de Intención de Tratar , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Calidad de Vida , Reoperación/estadística & datos numéricos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Trombosis/etiología , Resultado del Tratamiento , Prueba de PasoRESUMEN
AIMS: The ELEVATE Registry was designed to study long-term outcomes with the Heartmate 3 (HM3), a fully magnetically levitated centrifugal ventricular assist device, in a real-world population following CE-mark approval. METHODS AND RESULTS: A total of 540 patients, implanted in Europe and the Middle East were followed in ELEVATE. The registry included 463 patients receiving the HM3 as primary implant (Primary Implant Cohort), 19 patients underwent a pump upgrade from another device (Pump Exchange Cohort) and 58 patients who had experienced an outcome before having the possibility to sign the Informed Consent, for which only outcome data were collected (Anonymized Cohort). Data collection included demographics, survival, adverse events, EQ-5D Visual Analog Score quality of life (EQ-5D VAS QOL) questionnaire, and 6-min walk distance (6MWD). Mean age was 55.6 ± 11.7 years (89% male, 48% ischaemic cardiomyopathy). Seventy per cent of patients were in INTERMACS Profile 1-3 and 12.7% were on temporary mechanical circulatory support. Primary Implant Cohort survival was 83% after 2 years. In the Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation Primary Implant Cohort, strokes were observed in 10.2%, gastrointestinal bleedings in 9.7%, pump thrombosis in 1.5%, and outflow graft twists in 3.5%. Heartmate 3 implantation resulted in a significant and sustained improvement of functional capacity and QOL. CONCLUSION: In a real-world population, cohort implanted with the HM3 left ventricular assist device we demonstrate good long-term survival, sustained improvement of functional capacity, and low rates of adverse events (including pump thrombosis). CLINICALTRIALS.GOV IDENTIFIER: NCT02497950.
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Insuficiencia Cardíaca , Corazón Auxiliar , Adulto , Anciano , Europa (Continente) , Femenino , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Persona de Mediana Edad , Medio Oriente , Estudios Prospectivos , Calidad de Vida , Sistema de Registros , Resultado del TratamientoRESUMEN
BACKGROUND: Correction of valvular disease is often undertaken during left ventricular assist device (LVAD) implantation with uncertain benefit. We analyzed clinical outcomes with HeartMate 3 (HM3; Abbott) LVAD implantation in those with various concurrent valve procedures (HM3+VP) with those with an isolated LVAD implant (HM3 alone). METHODS: The study included 2200 patients with HM3 implanted within the Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 (MOMENTUM 3) trial portfolio who underwent 820 concurrent procedures among which 466 (21.8%) were HM3+VP. VPs included 101 aortic, 61 mitral, 163 tricuspid; 85 patients had multiple VPs. Perioperative complications, major adverse events, and survival were analyzed. RESULTS: Patients who underwent HM3+VP had higher-acuity Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profiles (1-2: 41% vs 31%) compared with no VPs (P < .05). The cardiopulmonary bypass time (124 vs 76 minutes; P < .0001) and hospital length of stay (20 vs 18 days; P < .0001) were longer in HM3+VP. A higher incidence of stroke (4.9% vs 2.4%), bleeding (33.9% vs 23.8%), and right heart failure (41.5% vs 29.6%) was noted in HM3+VP at 0 to 30 days (P < .01), with no difference in 30-day mortality (3.9% vs 3.3%) or 2-year survival (81.7% vs 80.8%). Analysis of individual VP showed no differences in survival compared to HM3 alone. No differences were noted among patients with either significant mitral (moderate or worse) or tricuspid (moderate or worse) regurgitation with or without corrective surgery. CONCLUSIONS: Concurrent VPs, commonly performed during LVAD implantation, are associated with increased morbidity during the index hospitalization, with no effect on short- and long-term survival. There is sufficient equipoise to consider a randomized trial on the benefit of commonly performed VPs (such as mitral or tricuspid regurgitation correction), during LVAD implantation.
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Insuficiencia Cardíaca , Corazón Auxiliar , Accidente Cerebrovascular , Procedimientos Quirúrgicos Torácicos , Humanos , Catéteres , Corazón Auxiliar/efectos adversos , Estudios Retrospectivos , Accidente Cerebrovascular/etiología , Resultado del Tratamiento , Estudios Multicéntricos como AsuntoRESUMEN
BACKGROUND: Clinical trials inform on average efficacy, but individualized risk assessments for outcome prediction are important in guiding treatment implementation. OBJECTIVES: The authors developed and validated a patient-specific risk score to predict survival at 1 and 2 years after HeartMate 3 (HM3) left ventricular assist device (LVAD) implantation. METHODS: The MOMENTUM 3 (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3) trial includes 2,200 HM3 LVAD patients in the pivotal trial and Continued Access Protocol study (2014-2018). The authors randomly assigned all patients to a derivation cohort (n = 1,540) or validation cohort (n = 660). Univariate mortality predictors were screened for potential model inclusion, stepwise selection was used to build the multivariable Cox proportional hazards regression model, and performance (discrimination and calibration) was evaluated. RESULTS: Age, prior cardiac surgery (coronary artery bypass grafting [CABG] or valve procedure), lower serum sodium, higher blood urea nitrogen (BUN), small left ventricular size, and right atrial pressure-to-pulmonary capillary wedge pressure (RAP/PCWP) ratio >0.6 were significant risk factors for mortality. Receiver-operating characteristic (ROC) analysis in the validation cohort demonstrated an area under the curve (AUC) of 0.76 (95% CI: 0.70-0.81) at 1 year and 0.71 (95% CI: 0.66-0.77) at 2 years. Calibration between predicted and observed survival of the risk quintiles was high, with Pearson correlation coefficients of 0.986 and 0.994 at 1 and 2 years, respectively. Patients were successfully stratified into tertiles with higher-than-average, average, and lower-than-average survival, and observed mortality risk increased by 2-fold from one tertile to the next. CONCLUSIONS: A practical, easy-to-use HM3 Survival Risk Score with 6 components was developed to accurately predict 1- and 2-year survival after HM3 LVAD implantation. The survival risk score can be used to provide individual survival estimates to facilitate shared decision making when considering HM3 LVAD therapy. (MOMENTUM 3 Trial Portfolio; NCT02224755, NCT02892955).
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Insuficiencia Cardíaca , Corazón Auxiliar , Humanos , Insuficiencia Cardíaca/terapia , Factores de Riesgo , Presión Esfenoidal Pulmonar , Medición de RiesgoRESUMEN
AIMS: Over decades, left ventricular assist device (LVAD) technology has transitioned from less durable bulky pumps to smaller continuous-flow pumps which have substantially improved long-term outcomes and quality of life. Contemporary LVAD therapy is beleaguered by haemocompatibility-related adverse events including thrombosis, stroke and bleeding. A fully magnetically levitated pump, the HeartMate 3 (HM3, Abbott, USA) LVAD, has been shown to be superior to the older HeartMate II (HMII, Abbott, USA) pump by improving haemocompatibility. Experience with the HM3 LVAD suggests near elimination of de-novo pump thrombosis, a marked reduction in stroke rates, and only a modest decrease in bleeding complications. Since the advent of continuous-flow LVAD therapy, patients have been prescribed a combination of aspirin and anticoagulation therapy on the presumption that platelet activation and perturbations to the haemostatic axis determine their necessity. Observational studies in patients implanted with the HM3 LVAD who suffer bleeding have suggested a signal of reduced subsequent bleeding events with withdrawal of aspirin. The notion of whether antiplatelet therapy can be avoided in an effort to reduce bleeding complications has now been advanced. METHODS: To evaluate this hypothesis and its clinical benefits, the Antiplatelet Removal and Hemocompatibility Events with the HeartMate 3 Pump (ARIES HM3) has been introduced as the first-ever international prospective, randomized, double-blind and placebo-controlled, non-inferiority trial in a patient population implanted with a LVAD. CONCLUSION: This paper reviews the biological and clinical role of aspirin (100 mg) with LVADs and discusses the rationale and design of the ARIES HM3 trial.
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Insuficiencia Cardíaca , Corazón Auxiliar , Aspirina , Insuficiencia Cardíaca/terapia , Humanos , Estudios Prospectivos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
BACKGROUND: The HeartMate 3 (HM3) is a Conformiteé Européenne (CE) mark-approved left ventricular assist device (LVAD) with a fully magnetically levitated rotor with features consisting of a wide range of operational speeds, wide flow paths and an artificial pulse. We performed a hemodynamic and echocardiographic evaluation of patients implanted with the HM3 LVAD to assess the speed range for optimal hemodynamic support. METHODS: Sixteen HM3 patients underwent pump speed ramp tests with right heart catheterization (including central venous pressure [CVP], pulmonary artery pressure, pulmonary capillary wedge pressure [PCWP] and blood pressure [BP]) and 3-dimensional echocardiography (3DE). Data were recorded at up to 13 speed settings. Speed changes were in steps of 100 revolutions per minute (rpm), starting at 4,600 rpm and ramping up to 6,200 rpm. RESULTS: Mean original speed was 5,306 ± 148 rpm, with a majority of patients (10 of 16, 62.5%) having normal CVPs and PCWPs at their original rpm settings. Going from lowest to highest speeds, cardiac output improved at the rate of 0.08 ± 0.08 liter/min per 100 rpm (total change 1.25 ± 1.20 liters/min) and PCWP decreased at the rate of -0.48 ± 0.27 mm Hg per 100 rpm (total change -6.13 ± 3.72 mm Hg). CVP and systolic BP did not change significantly with changes in rpm. Left ventricular end-diastolic dimension (LVEDD) decreased at a rate of -0.15 ± 0.09 cm per 100 rpm. Number of rpm was adjusted based on test results to achieve CVPs and PCWPs as close to normal limits as possible, which was feasible in 13 (81.3%) patients. For the remaining 3 patients, medical management was pursued to optimize hemodynamic support. CONCLUSION: Hemodynamic normalization of pressures was achieved in the majority of patients implanted with the HM3 pump within a narrow speed range.
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Insuficiencia Cardíaca/cirugía , Corazón Auxiliar , Hemodinámica/fisiología , Magnetismo/instrumentación , Función Ventricular Izquierda/fisiología , Anciano , Diseño de Equipo , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Estudios Prospectivos , Factores de TiempoRESUMEN
The HeartMate 3 left ventricular assist system (LVAS; St. Jude Medical, Inc., formerly Thoratec Corporation, Pleasanton, CA) was recently introduced into clinical trials for durable circulatory support in patients with medically refractory advanced-stage heart failure. This centrifugal, fully magnetically levitated, continuous-flow pump is engineered with the intent to enhance hemocompatibility and reduce shear stress on blood elements, while also possessing intrinsic pulsatility. Although bridge-to-transplant (BTT) and destination therapy (DT) are established dichotomous indications for durable left ventricular assist device (LVAD) support, clinical practice has challenged the appropriateness of these designations. The introduction of novel LVAD technology allows for the development of clinical trial designs to keep pace with current practices. The prospective, randomized Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 (MOMENTUM 3) clinical trial aims to evaluate the safety and effectiveness of the HeartMate 3 LVAS by demonstrating non-inferiority to the HeartMate II LVAS (also St. Jude Medical, Inc.). The innovative trial design includes patients enrolled under a single inclusion and exclusion criteria , regardless of the intended use of the device, with outcomes ascertained in the short term (ST, at 6 months) and long term (LT, at 2 years). This adaptive trial design includes a pre-specified safety phase (n = 30) analysis. The ST cohort includes the first 294 patients and the LT cohort includes the first 366 patients for evaluation of the composite primary end-point of survival to transplant, recovery or LVAD support free of debilitating stroke (modified Rankin score >3), or re-operation to replace the pump. As part of the adaptive design, an analysis by an independent statistician will determine whether sample size adjustment is required at pre-specified times during the study. A further 662 patients will be enrolled to reach a total of 1,028 patients for evaluation of the secondary end-point of pump replacement at 2 years.
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Protocolos Clínicos , Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Estudios Multicéntricos como Asunto/métodos , Diseño de Equipo , Humanos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
BACKGROUND: The incidence of percutaneous lead failure among patients supported with a HeartMate II left ventricular assist device is unknown. METHODS: All HeartMate II left ventricular assist device driveline dysfunctions reported to Thoratec Corporation were retrospectively reviewed. The location and severity of driveline failures and their association with adverse clinical outcomes were examined. Also, the effect of design modifications was evaluated. RESULTS: Between 2004 and October 2012, 12,969 HeartMate II pumps were implanted worldwide. The incidence of percutaneous lead dysfunction was 1,418 events occurring in 1,198 pumps (9.2% of pumps) over a cumulative support period of 13,932 patient-years (maximum, 8 years). Lead failure was mostly in the externalized part of the cable (87.2%). Lead dysfunction was managed by clamshell reinforcement of the external connector strain relief or by tape or silicone cable reinforcement in 76% of cases. Mortality or significant morbidity, including pump exchange or urgent transplant, or more complex cable repair occurred in 2.3% of all implanted pumps. The cumulative incidence of lead failures leading to major adverse clinical events has decreased with two lead design revisions: at 18 months postimplantation, the incidence was 6.2%±1.2% for the original design versus 2.2%±0.5% for the latest design change introduced in 2010 (log-rank p<0.001). CONCLUSIONS: Lead failures remain an important factor in the durability of left ventricular assist devices during long-term support. Most lead failures in the HeartMate II occurred in the externalized portion of the driveline, suggesting lead fatigue. The incidence of both internal and external lead failures has diminished since 2004 with improvements in lead design.
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Corazón Auxiliar , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Electrodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Falla de Prótesis , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: The HeartMate II (Thoratec, Pleasanton, CA) is an effective bridge to transplantation (BTT) but requires anti-coagulation with warfarin and aspirin. We evaluated the risk of thromboembolism and hemorrhage related to the degree of anti-coagulation as reflected by the international normalized ratio (INR). METHODS: INRs were measured monthly for 6 months in all discharged HeartMate II BTT patients and at an event. Each INR was assigned to ranges of INRs. Adverse events analyzed were ischemic and hemorrhagic stroke, pump thrombosis, and bleeding requiring surgery or transfusion. Events were correlated to the INR during the event and at the start of the month. RESULTS: In 331 patients discharged on support, 10 had thrombotic events (9 ischemic strokes, 3 pump thromboses), and 58 had hemorrhagic events (7 strokes, 4 hemorrhages requiring surgery, and 102 requiring transfusions). The median INR was 2.1 at discharge and 1.90 at 6 months. Although the incidence of stroke was low, 40% of ischemic strokes occurred in patients with INRs < 1.5 and 33% of hemorrhagic strokes were in patients with INRs > 3.0. The highest incidence of bleeding was at INRs > 2.5. CONCLUSIONS: The rate of thromboembolism during long-term outpatient support with the HeartMate II is low. The low number of thrombotic events appears to be offset by a greater number of hemorrhagic events. An appropriate target INR is 1.5 to 2.5 in addition to aspirin therapy. In patients having recurrent episodes of bleeding, the risk of lowering the target INR appears to be small.
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Anticoagulantes/uso terapéutico , Corazón Auxiliar/efectos adversos , Tromboembolia/epidemiología , Adolescente , Antagonistas Adrenérgicos beta/uso terapéutico , Adulto , Anciano , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Aspirina/uso terapéutico , Transfusión Sanguínea , Diseño de Equipo , Femenino , Trasplante de Corazón , Hemorragia/epidemiología , Hemorragia/cirugía , Humanos , Relación Normalizada Internacional , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Estudios Retrospectivos , Accidente Cerebrovascular/epidemiología , Warfarina/uso terapéutico , Adulto JovenRESUMEN
BACKGROUND: Neurocognitive (NC) changes in heart failure patients receiving left ventricular assist devices (LVADs) are not well understood. The purpose of this study was to document changes in the cognitive performance of patients with the continuous-flow HeartMate II LVAD as a bridge to transplant (BTT). METHODS: A NC protocol was used to evaluate patient performance at 1, 3 and 6 months after LVAD implantation at 11 centers. A total of 239 test sessions were completed in 93 patients including paired evaluations in 51 to 57 patients from 1 to 3 months, and in 20 to 28 patients with results from 1, 3 and 6 months. Five NC domains were assessed, including visual spatial perception, auditory and visual memory, executive functions, language and processing speed. RESULTS: There were statistically significant (p < 0.05), but limited improvements between 1, 3 and 6 months in NC domain performances as seen in visual memory, executive functions, visual spatial perception and processing speed. There were no significant declines in any neurocognitive test in any domain over these time periods. CONCLUSIONS: The cognitive performance of advanced heart failure patients remained stable or showed slight improvements from Month 1 to Month 6 of continuous-blood-flow support with the HeartMate II LVAD.
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Cognición/fisiología , Insuficiencia Cardíaca/psicología , Insuficiencia Cardíaca/cirugía , Corazón Auxiliar , Disfunción Ventricular Izquierda/psicología , Disfunción Ventricular Izquierda/cirugía , Adolescente , Adulto , Anciano , Femenino , Insuficiencia Cardíaca/fisiopatología , Trasplante de Corazón , Ventrículos Cardíacos/fisiopatología , Corazón Auxiliar/efectos adversos , Humanos , Lenguaje , Masculino , Memoria/fisiología , Persona de Mediana Edad , Estudios Prospectivos , Pruebas Psicológicas , Flujo Sanguíneo Regional/fisiología , Factores de Tiempo , Resultado del Tratamiento , Disfunción Ventricular Izquierda/fisiopatología , Percepción Visual/fisiología , Adulto JovenRESUMEN
This study updates our experience with hepatic artery infusion chemotherapy for colorectal liver metastases at the Lahey Clinic. It compares surgical versus percutaneous catheter methods, employing an external pump. The surgical series (SS) consisted of 58 patients (1970-1995) treated with floxuridine (FUDR), 20 mg/d for 4 to 5 weeks (modified in 1985; 2-week cycles). Percutaneous series (PS) consisted of 42 patients (1976-1995) treated with fluorouracil (5-FU), 20 mg/d for 10 days followed by a floxuridine (FUDR) schedule as with SS. Analysis consisted of tumor response, survival, and toxicity data between the two methods. Response rates showed no significant difference, SS (34%) and PS (48%) (P = 0.22). There were no significant differences in survival from treatment until death in SS (n = 58) of 13 months versus PS (n = 42) of 10.6 months (P = 0.39), from diagnosis until death, SS being 28.4 months versus PS of 26.4 months (P = 0.71) and from metastases until death, SS being 17.4 months versus PS of 22.2 months (P = 0.35). Hepatic toxicity was similar, but there was increased bone marrow toxicity, mucositis, and diarrhea for the PS. Response rates are similar for both our SS and PS and to that reported in recently randomized surgical trials. Hepatic artery infusion chemotherapy with FUDR by percutaneous catheter placement may be as effective as surgical catheter placement for colorectal liver metastases, but further study is needed.
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Antimetabolitos Antineoplásicos/administración & dosificación , Neoplasias Colorrectales/patología , Floxuridina/administración & dosificación , Fluorouracilo/administración & dosificación , Arteria Hepática , Infusiones Intraarteriales/métodos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Adulto , Anciano , Arteria Braquial , Cateterismo Periférico , Femenino , Humanos , Bombas de Infusión , Masculino , Persona de Mediana Edad , Análisis de SupervivenciaRESUMEN
BACKGROUND: Left ventricular assist device (LVAD) failure and malfunction rates are critical gauges for establishing LVADs as a long-term therapy for end-stage heart failure patients. These device performance measures, however, have been inadequately characterized in the bridge-to-transplantation literature. METHODS: REMATCH is a randomized trial that compares optimal medical management with LVAD implantation for patients with end-stage heart failure. An independent committee adjudicated patient outcomes. The primary endpoint--survival--was analyzed by intention to treat using the log-rank statistic. Frequency of event occurrence was analyzed by Poisson regression. The time to first event was analyzed by the product limit method. Device performance was disaggregated into confirmed malfunctions and system failures. The latter were events in which patients could not be rescued with backup circulatory support measures. RESULTS: The 1-year survival rate was 52% (95% confidence limit [CL]; 40%-63%) for LVAD patients versus 28% (95% CL; 17%-39%) for medical patients and the 2-year survival rate was 29% (95% CL; 19%-40%) for LVAD patients versus 13% (95% CL; 5%-22%) for medical patients. System failure was 0.13 per patient per year and the confirmed LVAD malfunction rate was 0.90. Freedom from device replacement was 87% at 1 year and 37% at 2 years. CONCLUSIONS: Despite the observed rates of device malfunction and replacement, LVAD implantation confers clinically significant improvement with regard to survival as compared with medical management. Device modifications and innovations for infection management exhibit great promise of improving device performance in the near future.