PARADOX OF MYOCARDIAL ISCHEMIA AND NECROSIS IN YOUNG WOMEN WITH NORMAL CORONARY ARTERIOGRAMS . RELATION TO ABNORMAL HEMOGLOBIN-OXYGEN DISSOCIATION

A double-blind study was carried out on 15 premenopausal women under 40 years of age who showed objective evidence of myocardial ischemia or necrosis as demonstrated by electrocardiogram or enzyme studies, or both. In each, selective coronary arteriography was normal. Three women later died with single or multiple subendocardial infarcts. None had disease of the large or small coronary arteries. None had a predisposing cause of premature coronary artery disease, except that 8 smoked cigarettes and 4 were obese. Abnormal hemoglobin-oxygen dissociation was found in 14 of the 15 women with myocardial ischemia or necrosis. Among 3 who discontinued cigarette smoking, the anomalous dissociation returned to normal within one month of cessation of cigarettes. In the other 5 it remained anomalous. Fifteen age-matched control women were also studied by double-blind technic. Abnormal dissociation was found in the 1 control subject who smoked (more than 12 cigarettes daily for more than 15 years). Selective coronary arteriograms were not performed among women in the control group. The strong correlation between the empiric observation of abnormal hemoglobin-oxygen dissociation and the presence of myocardial ischemia and necrosis with normal coronary arteriograms suggests that there may be a relation. This may be true in view of the high oxygen demands of the myocardium (especially the subendocardium). It is possible that inefficient or slow release of oxygen by hemoglobin could contribute to myocardial ischemia or necrosis. Alternatively, the hemoglobin-oxygen affinity changes may be secondary stress phenomena." Electrocardiographic abnormalities occurring at rest during forced hyperventilation appear to aid in predicting the laboratory abnormality. Propranolol is often effective in treating this condition. © 1969."