ABSTRACT
A prospective, randomised, double-blind study was performed to compare the effects of propranolol and placebo on sudden cardiac death in a high-risk group of patients who survived acute myocardial infarction. Altogether 4929 patients with definite acute myocardial infarction were screened for inclusion: 574 (11.6%) died before randomisation, and 3795 (77%) were excluded. Five hundred and sixty patients aged 35 to 70 years were stratified into two risk groups and randomly assigned treatment with propranolol 40 mg four times a day or placebo. Treatment started four to six days after the infarction. By one year there had been 11 sudden deaths in the propranolol group and 23 in the placebo group (p less than 0.038, two-tailed test analysed according to the "intention-to-treat" principle). Altogether there were 25 deaths in the propranolol group and 37 in the placebo group (P less than 0.12), with 16 and 21 non-fatal reinfarctions respectively. A quarter of the patients were withdrawn from each group. Withdrawal because of heart failure during the first two weeks of treatment was significantly more common among propranolol-treated patients than among the controls, but thereafter the withdrawal rate was the same. The significant reduction in sudden death was comparable with that after alprenolol, practolol, and timolol, which suggests that the mechanism of prevention is beta-blockade rather than any other pharmacological property of the individual drugs.
Subject(s)
Myocardial Infarction/drug therapy , Propranolol/therapeutic use , Adult , Aged , Clinical Trials as Topic , Death, Sudden , Double-Blind Method , Female , Heart Arrest/prevention & control , Humans , Male , Middle Aged , Myocardial Infarction/mortality , Myocardial Infarction/prevention & control , Propranolol/adverse effects , Random Allocation , Time FactorsABSTRACT
The first in vivo haemodynamic observations of the recently developed Hall-Kaster central flow prosthetic heart valve are reported. Haemodynamic evaluation of valve function was performed both in acute and chronic experiments following implantation of the Hall-Kaster prosthesis in the mitral position in dogs. These studies showed a low transvalvular pressure gradient, an effective opening angle of about 70 degrees and good diastolic flow through both the large and small orifices of the prosthesis. A slow rotational movement was depicted by the disc during opening and closure.
Subject(s)
Heart Valve Prosthesis , Hemodynamics , Mitral Valve/surgery , Animals , Atrial Function , Blood Pressure , Cardiac Output , Dogs , Evaluation Studies as Topic , Heart Valve Prosthesis/adverse effects , Mitral Valve/diagnostic imaging , Prosthesis Design , Pulmonary Artery/physiology , Radiography , Thrombosis/etiology , Ventricular FunctionSubject(s)
Arrhythmias, Cardiac/therapy , Pacemaker, Artificial , Adult , Aged , Female , Heart Block/therapy , Humans , Male , Middle Aged , Sinoatrial Block/therapyABSTRACT
We report on the effect of verapamil in 12 patients suffering from pulmonary hypertension. The drug caused a slight, but statistically significant decrease in mean pulmonary artery pressure and in the work performance by the right ventricle. The mean pressure of the right atrium, the end-diastolic pressure of the right ventricle, the pulmonary arteriolar resistance, the cardiac index and the stroke volume were not significantly changed, however, and there was a wide spread of the values observed. In some patients the drug exerted a marked negative inotropic effect, with a concomitant increase in the pulmonary arteriolar resistance.
