Adenosine-Induced Myocardial Ischemia in a Patient with Myocardial Bridge: A Case Report

The adenosine stress test and exercise stress test have been widely used in the diagnosis of coronary heart disease, which has high sensitivity and specificity for diagnosis of coronary heart disease. The myocardial bridge is a congenital dysplasia of the coronary artery which may cause severe myocardial ischemia, acute myocardial infarction, arrhythmia, and sudden death. Although drug therapy for this disease is clear and widely used, indication for open-chest surgery is still vague. This case shows a patient with long-term chest pain undergoing the coronary computed tomographic angiography in our hospital 1 month ago, which showed the mild myocardial bridge in the left anterior descending (LAD) branch. Then, she did the mental stress-induced myocardial ischemia and cardiopulmonary exercise test which the results were negative. After the informed consent, the patient took the adenosine stress test and severe angina occurred during the test. Later, coronary angiography showed that the myocardial bridge caused 70% contraction of the middle segment of the LAD branch. In the case of long-term ineffective drug treatment, the patient underwent a open-chest surgery called coronary artery myotomy and her chest discomfort eventually recovered. To a degree, adenosine stress test may be more sensitive than exercise stress test in predicting the severity of coronary artery stenosis. Moreover, we may provide a unique direction of indication for surgeons to operate open-chest surgery on the myocardial bridge.