Myocardial recovery during left ventricular unloading in patients with dilated cardiomyopathy: Prediction of cardiac stability in the case of assist device explantation

Aims: During unloading, cardiac recovery which allows ventricular assist device (VAD) explantation is possible. To improve weaning decisions we sought predictive parameters for post-weaning stability.

Methods: We evaluated „off-pump“ echo-parameters obtained before VAD explantation, histological changes, serum anti-ß1-adrenoreceptor-autoantibody disappearance during unloading, VAD-support duration and heart failure (HF) history. Among 79 patients weaned since 3/1995, a homogenous group of 35 idiopathic dilated cardiomyopathy (IDCM) patients weaned from LVADs were selected for evaluation.

Results: The 8-year post-weaning survival reached 78.1±8.2%. Post-weaning freedom from HF recurrence at 4 years was 69.3±8.1%. Patients with post-weaning cardiac stability were younger, HF history and recovery time during unloading shorter, LV short/long axis-ratio lower and systolic wall motion velocity higher (p<0.05). For LVEF <45% at enddiastolic diameter (LVEDD) ≤55mm the positive predictive value for ≥4years cardiac stability reached 90.5%. There was no HF recurrence during the first 4 years if LVEF was ≥45%, LVEDD ≤55% and history of HF <5years. The LVEF time-course during the first 6 post-weaning months also appeared predictive for long-term stability. History of HF >5years showed a 90% predictive value for HF recurrence during the first 3 years. Neither reduction in myocardial hypertrophy and fibrosis nor anti-ß1-adrenoreceptor-autoantibody disappearance during unloading appeared predictive for post-weaning outcome.

Conclusions: Off-pump LVEF and LVEDD, time-course of LVEF during the first 6 post-weaning months and HF duration are predictive for outcome after LVAD removal in IDCM. Patients' age, altered LV geometry, low wall motion velocity and prolonged LVAD support until improvement (>6 months) are risk factors for HF recurrence.