Haemodynamic and electrocardiographic effects of frusemide during supine exercise in patients with angina pectoris.

The influence offrusemide on haemodynamic, electrocardiographic, and symptomatic response to exercise was studied in 19 patients with documented coronary artery disease. During the control exercise period all patients experienced angina and showed ST segment depression, accompanied by raised pulmonary artery wedge pressures (PWP). In 12 of these patients 40 mg frusemide was administered intravenously and in the other seven patients 40 mg frusemide was given orally. After significant diuresis (>400 ml), the exercise test was repeated. Data were collected at the same exercise work load and duration as had been achieved before frusemide. Both in the intravenous and oral group there was a reduction in cardiac output at rest and a less obvious reduction during exercise. The PWP during exercise after intravenous frusemide decreased from 32-9 to 11P8 mmHg and after oral frusemide from 30 7 to 15-7 mmHg. During the control period there was evidence of mitral regurgitation in seven of the patients during angina, as shown by high amplitude v waves in the PWP recordings. These alterations disappeared completely after the administration of frusemide. Ischaemic ST depression improved in 15 of 19 patients after frusemide (0-21 vs 0 09 mV). Furthermore, there was a reduction of complete suppression of anginal pain in 18 of 19 patients. Ten patients were capable of continuing exercise for a further period of time at the same work load. These data, demonstrating the antianginal properties of frusemide, may be explained by the reduction in ventricular volumes and pressures, resulting in a decrease in myocardial wall stress and oxygen demand. The effects may be the result ofboth the diuretic action offrusemide and its venodilator capacity.