patients with angina decubitus （AD） were studied during hospitalization. These patients were found to have severe coronary artery obstructive lesions and an increase of myocardial oxygen consumption （MOC） before the onset to AD

indicating that AD belongs to the category of effort angina.18 patients were investigated by continuous hemodynamic monitoring. Three patients had significant increase in pulmonary artery diastolic pressure （PADP） before the onset. In the other 15 patients. PADP increased slightly in 12 and remained unchanged in 3 cases before the onset. Left ventriculography showed ejection fraction （EF）>45% in 25 of the 27 patients. These results indicate that left ventricular （LV） systolic dysfunction is not a major factor in the Pathogenesis of AD. The patients with LVEDP>12 mmHg constituted 60% of 25 patients with EF>45%

suggesting that these patients had ohvious LV diastolic dysfunction

which may be the major factor in the pathogenesis of AD.According to the results of our treatment

beta blockers may be used as the major form of tteatment in the patients with AD.