LONG-TERM USE OF K-STROPHANTHIN IN ADVANCED CONGESTIVE-HEART-FAILURE DUE TO DILATED CARDIOMYOPATHY - A DOUBLE-BLIND CROSSOVER EVALUATION VERSUS DIGOXIN

K-strophanthin or digoxin were added to diuretics (all cases) and vaso dilators (most cases) for treating advanced congestive heart failure i n 22 patients with dilated cardiomyopathy and sinus rhythm. K-strophan thin (0.125 mg intravenously) or digoxin (0.25 mg orally) were adminis tered daily in two 3-month periods, during which vasodilators and diur etics were kept constant and patients received one of the two digitali s preparations in a double-blind fashion, crossing over to the alterna tive preparation in the next period. Blindness was assured throughout the trial with a daily intravenous injection of 10 ml normal saline so lution either containing K-strophan-thin or not, and with daily oral a dministration of either placebo or active digoxin. At the end of the r un-in period, 15 days after starting active preparations, and thereaft er every month for the next 6 months, we evaluated left ventricular pu mp function at rest and patients' functional performance by a cardiopu lmonary exercise test. At Day 15, cardiac index and ejection fraction at rest, compared with run-in, were significantly raised with both gly cosides; during exercise while on K-strophanthin, peak oxygen consumpt ion was augmented by 1.4 ml/min/kg (p < 0.01) and oxygen consumption a t anaerobic threshold by 2.2 ml/min/kg (p < 0.01); corresponding varia tions on digoxin (-0.1 and +0.3, respectively) were not significant ve rsus run-in. These patterns were duplicated at repeated tests during f ollow-up. In the entire population, means for oxygen consumption at pe ak exercise and at anaerobic threshold were raised from run-in values by 1.4 (p < 0.01) and 2.2 ml/min/kg (p < 0.01), respectively, after 3 months of K-strophanthin treatment, and by 0.0 and 0.1 ml/min/kg, resp ectively, after treatment with digoxin for the same period of time. Re sults were similar in nine patients when they were given digoxin intra venously (0.25 mg/day) for 1 week after having completed the trial wit h the oral digoxin preparation. These results indicate that K-strophan thin improved functional performance in patients with severe cardiac d ecompensation due to dilated cardiomyopathy; digoxin failed to provide the same results, independent of the drug sequence or the route of ad ministration. The reasons for these differences are basically unknown and do not seem to be related only to changes in cardiac performance a t rest, because both K-strophanthin and digoxin significantly and pers istently raised cardiac output and ejection fraction at rest.