Except for the electrocardiogram objective evaluation of the functional state of the coronary circulation in man is often difficult. The nature of the coronary circulation in the presence of known coronary insufficiency has not been evaluated. In this report, 17 patients were studied of whom 14 had angina pectoris. Observations were made of coronary blood flow and hemodynamics both at rest and following administration of nitroglycerin. The authors conclude that resting coronary flow is normal, but cannot increase further with dilators. They consider this phenomenon a consequence of prior exhaustion of the dilator capacity of the arterioles in compensation for the atherosclerotic obstruction of the coronary tree. The "fixed flow" concept is suggested as an objective means of detecting coronary insufficiency. Nitrites probably relieve pain in some manner other than general coronary dilatation.U NTIL the present time few objective assessments' of the state of the coronary ('irculatioll have been made except for electrocardiographic and ballistocardiographic observations. In these studies correlation was possible only with clinical findings and postmortem observations. The electrocardiogram has been extremely helpful, particularly when it has indicated myocardial isehemia. As has been pointed out by many workers, however, it gives only indirect information concerning the state and adequacy of the coronary eiren-

No abstract

A 63-year-old male with status post quadruple aortocoronary bypass surgery suddenly complained of chest pain and had ST-segment elevation in lead III during routine coronary angiography. Subsequent selective injections showed occlusion of the bypass graft to the right coronary artery, whereas by digital angiography done 15 min earlier it had been patient. Iatrogenic dissection of the graft was assumed, and balloon recanalization was immediately performed. Chest pain and signs of ischemia rapidly resolved, and no evidence of myocardial infarction was found until hospital discharge.

The case of a 10--year-old boy is reported because of the association of the Ehlers-Danlos syndrome with bifidity of the pulmonary artery and anomaly of the aortic arch. The cardiovascular aspects of this connective-tissue disorder are reviewed, and the possibility of another common feature with the Marfan syndrome is briefly discussed.

No abstract