Intractable heart failure despite angiotensin-converting enzyme inhibitors, digoxin, and diuretics: long-term effectiveness of add-on therapy with pimobendan

Abstract

In 25 patients whose chronic congestive heart failure (CHF) had recently worsened to New York Heart Association class IV, pimobendan (5 to 20 mg/day) was added to maximum conventional therapy consisting of digoxin, diuretics, angiotensin-converting enzyme inhibitors, coumadin derivatives to prevent thromboembolic complications, and amiodarone to suppress serious ventricular rhythm disturbances. CHF was fatal in less than 1 month in five patients (two had shown some initial improvement). The other 20 had sustained improvement by at least one functional class, interrupted by episodes of CHF that usually responded to intravenous therapy. Median survival was 12 months (range 10 days to greater than 3 years); five patients died suddenly, 12 died of intractable CHF, and two died of other causes. Six patients were alive 3 years after the onset of treatment with pimobendan. Add-on therapy with pimobendan produced a sustained improvement in many patients with severe CHF that was no longer responding to a combination of digoxin, diuretics, and angiotensin-converting enzyme inhibitors.