Abstract 13124: Outcomes of Mechanical Circulatory Support for Destination Therapy in NYHA Class IIIB Patients
Background: An established selection criterion for destination therapy (DT) left ventricular assist device (LVAD) implantation is NYHA Class IV symptoms refractory to medical management. The HeartMate II (HMII) DT trial expanded enrollment to include NYHA Class IIIB patients (pts).
Hypothesis: Class IIIB and IV pts derive similar survival outcomes and quality of life improvements with LVAD therapy.
Methods: In a prospective, multi-center trial, 567 pts (n=160 Class IIIB, 407 Class IV) with contraindications to heart transplantation received a HMII continuous flow (CF) LVAD. Pts also were required to have peak VO2 < 14 ml/kg/min, optimal medical management for 45 of the prior 60 days, or inotropic support for ≥14 days or intra-aortic balloon pump (IABP) for ≥ 7 days. Outcomes in pts with Class IIIB vs IV symptoms were compared.
Results: At baseline, Class IIIB pts had lower mean pulmonary capillary wedge (22 vs. 25 mmHg, p=0.007) and central venous pressures (12 vs.13 mmHg, p=0.02), and higher pre-albumin (21 vs. 18 mg/dl, p=0.001). LV ejection fraction (17%), creatinine (1.5 mg/dl) and prior stroke (10% vs 16%) were similar between cohorts. Pre-operative use of inotropes (68% vs. 81%, p=0.002) and IABP (10% vs. 25%, p<0.0001) were less frequent in Class IIIB. Survival trended higher in IIIB pts (Figure). Adverse event rates (events/pt-yr) for bleeding (1.77 vs. 1.78), device-related infection (0.24 vs. 0.29), and stroke (0.11 vs. 0.11) were similar or lower for Class IIIB vs IV. Improvements in 6 minute walk distance and NYHA Class were similar between groups with >80% of patients in Class I or II between 6–24 months after implantation, and QoL score improvements of >40 points in both groups.
Conclusions: Class IIIB pts who met other entry criteria in the HeartMate II DT trial defined a population only slightly less ill and with much overlap with Class IV pts. Class IIIB pts derived similar survival, functional and quality of life benefits from the CF LVAD compared to Class IV patients.
- © 2010 by American Heart Association, Inc.