How useful is digitalis in patients with congestive heart failure and sinus rhythm?

Clinical, haemodynamic, and pharmacological effects of withdrawal and reintroduction of digoxin in patients with heart failure in sinus rhythm after long term treatment

A randomised, double blind, placebo controlled, crossover study of digoxin withdrawal and reintroduction was carried out over two periods of eight weeks each after long term treatment. Forty four patients with stable heart failure in sinus rhythm and plasma digoxin concentrations over 0.8 ng/ml were studied. Their progress was assessed by clinical criteria, by haemodynamic measurements (systolic time intervals and echocardiography), and by pharmacological measurements of erythrocytic sodium pump numbers and activity. After withdrawal of digoxin clinical deterioration occurred in only 25% of the patients. Furthermore, in only 9% of cases was digoxin reintroduction thought to be necessary. There was deterioration in only 11% of the patients during digoxin treatment. Deterioration during digoxin withdrawal was accompanied by changes in systolic time intervals, but similar, albeit smaller changes in systolic time intervals also occurred in patients with no deterioration. Deterioration was accompanied by changes in the pharmacological effects of digoxin on the erythrocytes, consistent with a loss of effect, and these changes did not occur in those who did not deteriorate. The occurrence of deterioration could not be predicted by any clinical, haemodynamic, or pharmacological measurements made before withdrawal.

Effect of ibopamine on the failing heart at rest and during isometric exercise: a noninvasive study

Eleven patients suffering from heart failure were treated with oral ibopamine, a di-isobutyric ester of N-methyldopamine, 100 mg three times a day for 1 week and 200 mg three times a day for 3 weeks. Therapy was discontinued by one patient because of tachycardia. Left ventricular performance was evaluated with echocardiography and systolic time intervals at rest and after 3 minutes of isometric exercise using a handgrip. Six of 10 patients completing the study were in New York Heart Association (NYHA) functional class III, 2 in class IV, and 2 in class II. All patients, except one who remained stable in class II, improved their subjective condition by one functional class during 4 weeks of therapy (p less than 0.01). There were no changes in heart rate, blood pressure, rate-pressure product, cardiac index, or total peripheral vascular resistance. The left ventricular end-systolic diameter decreased after four weeks from 71.2 +/- 12.7 (SD) to 65.9 +/- 13.0 mm (p less than 0.001); the left ventricular end-diastolic diameter did not change. The ejection fraction increased from 26 +/- 8 to 32 +/- 9% (p less than 0.01). Afterload, that is, left ventricular circumferential systolic wall stress, declined as a result of decreased systolic diameter. Systolic time intervals did not vary. There were no changes due to ibopamine during isometric exercise probably owing to increased beta-adrenergic stimulation induced by the handgrip. Neither urine volume nor body weight changed. Side effects were mild except for tachycardia of one patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute hemodynamic and metabolic effects of ICI 118,587 (Corwin), a selective partial beta 1 agonist, in patients with dilated cardiomyopathy

The effects of acute intravenous administration of ICI 118,587 (Corwin), a partial beta 1 agonist, were studied in nine patients with dilated cardiomyopathy and symptomatic congestive heart failure. Hemodynamic and metabolic parameters were measured using Swan-Ganz, arterial, and coronary sinus catheters. Repeated doses of Corwin produced no significant change in left ventricular performance, while a trend towards decreased blood pressure and stroke work was seen. No change occurred in coronary sinus blood flow, transmyocardial lactate extraction, or catecholamine release. One patient had significant depression of left ventricular function with hypotension. Thus, acute infusion of Corwin produced no beneficial inotropic responses, but rather produced features suggestive of further myocardial depression.