Tatooles, Antone

Introduction: Advanced age is a risk factor for poor outcomes following left ventricular assist device (LVAD) implant. A means of identifying elderly patients with acceptable mortality risk following LVAD surgery is not currently available. The HeartMate II (HMII) Risk Score (HMRS) was recently developed and validated, providing good risk discrimination for predicting survival in patients undergoing HMII implant. Independent survival predictors in the model included age and markers of renal function, coagulopathy and nutrition. We hypothesize that the HMRS will provide utility for risk stratification of the elderly LVAD candidate. Methods: Elderly patients (age >65 years) enrolled into the HMII Destination Therapy (DT) and Bridge to Transplant trials were selected for the study (n=444). Complete data for HMRS calculation was available in 98% (n=435). Preoperative patient HMRS was calculated according to the formula: HMRS = ln(1.29)*decade of age + ln(0.71)*Albumin + ln(1.37)*Cr + ln(1.86)*INR + ln(0.52)*LVAD Center Volume >=15 + ln(0.67)*Implant after 2007. Patients were trichotimized into high (HMRS >1.0), medium (HMRS 0.50-1.0), and low (HMRS <=0.50) risk categories (as previously defined in model development) based on HMRS. The primary endpoint was survival at 1 year following LVAD implant, estimated using Kaplan-Meier methods. Results: The mean cohort age was 71±4 years and 84% (n=372) had devices implanted for DT. The table shows the HMRS along with mean±stddev values for the score's components. All between-group differences were statistically significant (Kruskal-Wallis p<0.05), although differences in age were not clinically significant. Survival based on HMRS strata is shown in the figure. Patients in the low and medium risk groups had survivals >80% at 1 year following LVAD implant. Conclusions: The HMRS can be used to identify elderly patients with survivals comparable to that of the general LVAD population.

Background— The HeartMate II (HMII) destination therapy (DT) trial demonstrated significant improvements in outcomes in continuous-flow left ventricular assist devices compared with patients implanted with the pulsatile-flow HeartMate XVE. The primary hypothesis of the current study is that trial patients enrolled after the initial data cohort would have better clinical outcomes. Methods and Results— Two hundred eighty-one patients who underwent HMII for DT from May 2007 to March 2009 (Mid Trial [MT] group) were compared with the initial 133 HMII patients from March 2005 to May 2007 (Early Trial [ET] group). Patient entry criteria were the same during the 2 time periods. Survival, adverse events, and quality of life were compared between the 2 groups. Baseline characteristics were similar between the groups. Compared with the ET group, patients in the MT group had reduced adverse event rates for bleeding requiring transfusions (1.66 versus 1.13 events per patient-year, P <0.001), sepsis (0.38 versus 0.27, P =0.025), device-related infections (0.47 versus 0.27, P <0.001), and hemorrhagic stroke (0.07 versus 0.03, P =0.01). Other event rates were similar between groups including ischemic stroke (0.06 versus 0.05 events per patient-year, P =0.57). Survival at 1 year in the MT group was 73% versus 68% in the ET group ( P =0.21). Additionally, there was a significant reduction in deaths caused by hemorrhagic stroke ( P =0.01). Quality of life improvements were significant in both the groups ( P <0.001). Conclusions— The benefit of DT therapy with the HMII is confirmed in subsequent trial patients, with improved adverse event rates and a strong trend for improvements in survival. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00121485.