Who would be a candidate for bridge to recovery during prolonged mechanical left ventricular support in idiopathic dilated cardiomyopathy?

Objectives: We sought to elucidate the incidence and timing of myocardial recovery in patients with idiopathic dilated cardiornyopathy during prolonged support with a left ventricular assist system and to characterize the factors influencing this phenomenon. Methods: Since 2000, 11 patients (mean age, 27.9 years) with end-stage heart failure caused by dilated cardiornyopathy were supported with a left ventricular assist system for more than 6 months. All patients had aggressive pharmacologic treatment, including beta-blockers, together with unloading by means of a left ventricular assist system. Results: During 239 to 663 days (mean, 453 days) of left ventricular assist system support, 5 patients had significant recovery of cardiac function and successfully underwent left ventricular assist system removal. All of these patients have remained in New York Heart Association class 1 during 8 to 29 months of follow-up. The improvement of left ventricular function started at various times. In particular, 2 of 5 recovered patients started to show improvement after 1 year of left ventricular assist system support. The myocardial fibrosis did not resolve but rather worsened in all patients during left ventricular assist system support. However, myocardial fibrosis was less severe in the recovered group (17.7% +/- 8.2% at left ventricular assist system implantation vs 20.1% +/- 5.2% at explantation) in comparison with that in the nonrecovered group (30.5% +/- 13.2% vs 48.4% +/- 5.1%) both before and after use of the left ventricular assist system. Conclusion: Patients with severe congestive heart failure caused by dilated cardiomyopathy have a good chance of myocardial recovery and successful explantation of the left ventricular assist system. A relatively slow response of myocardial recovery during prolonged left ventricular assist system support was demonstrated in some patients. A lesser degree of fibrotic changes in the left ventricle was predictive of recovery.