A new method of monitoring recovery and weaning the thoratec left ventricular assist device

Background. Recent scientific and clinical data suggest that chronic mechan ical ventricular unloading may lead to myocardial recovery. Evaluating and monitoring patients for myocardial recovery and the optimal methods of wean ing the left ventricular assist device are not well defined. Methods. Six patients with advanced heart failure and severe mitral regurgi tation have undergone successful bridge to recovery using a Thoratec left v entricular assist device. Data that details their monitoring for myocardial recovery and weaning from the left ventricular assist device were prospect ively collected. Results. Clinical data collected during the recovery phase included chest r oentgenogram, echocardiography, plasma norepinephrine, tumor necrosis facto r-alpha, bioimpedance, and cardiopulmonary exercise testing (peak oxygen co nsumption). Normalization of these variables with a 10% increase in the pea k oxygen consumption was obtained before weaning. The Thoratec device rate and percent systole were manipulated to allow gradual reloading of the vent ricle. The weaning process occurred for more than 5 to 10 days to allow tim e for observation of the ventricle and its response to the increasing workl oad. Conclusions. Select patients with advanced congestive heart failure and sev ere mitral insufficiency can benefit from mechanical device support. We des cribe our technique of monitoring for myocardial recovery using clinical va riables. Our technique of weaning allows for gradual reloading of the ventr icle and a longer period of observation before device removal. Additional r esearch is needed to determine which variables will accurately predict long -term myocardial recovery and the optimal weaning method. (Ann Thorac Surg 2001;71:215-8) (C) 2001 by The Society of Thoracic Surgeons.