CASE REPORTS Reduction of Coronary Blood Flow during Coronary Artery Spasm Occurring Spontaneously and after Provocation by Ergonovine Maleate

SUMMARY A 50-year-old man suffering from recurrent chest pain accompanied by transient ST-segment elevation developed spasm of the left anterior descending coronary artery after receiving ergonovine maleate. During spontaneous chest pain, thermodilution coronary sinus blood flow fell from 96 ml/min to 46 ml/min, while the coronary sinus arteriovenous oxygen difference widened from 9.82 volumes percent to 11.3 volumes percent. During spontaneous relief of pain, coincident with resolution of the ST-segment changes, coronary sinus blood flow gradually rose to 135 mI/min, while cor-CHEST PAIN occurs as a result of transient coronary artery spasm ' in some patients with variant angina pectoris.2 Reduction in myocardial perfusion, suggested by accom-panying ST-segment elevation, recently has been documented by thallium-201 imaging.3 ' 4The magnitude of the reduced coronary artery blood flow that occurs as a con