Rest angina induced by coronary artery spasm at the first septal artery: a case report

A 41-year-old man was admitted because of chest pain at rest. The exercise test and coronary angiography were performed after all antianginal medication was discontinued for 24 hours. During the graded treadmill exercise stress test using the Bruce protocol, the patient had anginal pain with the electrocardiogram (ECG) showing ST segment elevation in leads V1 and V2. A baseline coronary angiogram disclosed 50% stenosis of the first septal branch of the left coronary artery. After a bolus of 0.1 mg ergonovine was administered into the coronary artery, the patient complained of typical anginal pain. Complete occlusion of the first septal branch was demonstrated, associated with significant ST segment elevation in leads V1-V3, right bundle branch block, and electrical axis deviation to the left on the ECG. The coronary occlusion reversed soon after nitroglycerin administration into the coronary artery. We diagnosed a rare case of angina pectoris caused by spasm of the minor branch of coronary artery, and that serial ECG changes might demonstrate ventricular septal ischemia including the cardiac conduction system. ST segment elevation in leads V1-V3 indicated ischemia of the ventricular septum, and right bundle branch block, axis deviation to the left, and increased amplitude of the precordial R wave might be induced by ischemia of the right bundle branch, left anterior bundle branch and septal branch in the cardiac conduction system supplied by the septal branches of the left anterior descending coronary artery.