CHRONIC SYMPATHETIC SUPPRESSION IN THE TREATMENT OF CHRONIC CONGESTIVE-HEART-FAILURE

Previous short-term studies demonstrated that treatment with clonidine produced significant hemodynamic improvement in patients with congest ive heart failure (CHF). In this study we followed 12 CHF patients (10 M, 2 F age 63 +/- 11, 10 with ischemic cardiomyopathy and 2 with dila ted cardiomyopathy) treated with 0.15 or 0.075 mg oral clonidine twice daily for 13 +/- 5 months (range 6-23), with functional evaluation at baseline, 6 weeks and 6 months. There was suppression of circulating cateholamines, associated with significant ameliorations in NYHA class , in duration of exercise tolerance (from 246 +/- 68 sec to 362 +/- 30 and 459 +/- 70 sec, respectively p < 0.02), in ejection fraction (fro m 32 +/- 7% to 35 +/- 5 and 39 +/- 7% p < 0.04) and in left ventricula r enlargement as assessed echocardiographically. There were also impro vements in a number of electrophysiologic parameters calculated by com puterized analysis of ambulatory ECG tapes, such as heart rate variabi lity, indicating diminished propensity to malignant arrhythmias, as co nfirmed by decreases in the numbers of isolated premature ventricular contractions, couplets and episodes of non-sustained ventricular tachy cardia, The data suggest that chronic central sympathetic suppression with clonidine in CHF results in significant functional amelioration a nd improved electrophysiologic stability.