A 47 year old Japanese male with exertional shortness of breath, cardiac murmur and ECG abnormalities was examined with invasive and non-invasive cardiology techniques that disclosed hypertrophic cardiomyopathy, and the anomalous origin of the left coronary artery from the right sinus of Valsalva. Although both situations have been known to cause sudden death especially under a state of strenuous physical stress, his exercise thallium scintigraphy performed with the symptom limited maximal test did not uncover any significant myocardial ischemia or exercise induced malignant arrhythmias. This is a very rare association of two distinctly identified clinical situations highly indicative of a likelihood of sudden cardiac death. Therefore, careful observation is needed.