The patient’s diagnosis was uncommon for a person who was generally inactive—and in good health. A 44-year-old Hispanic man underwent evaluation for episodes of nonexercise-related chest pain localized to the precordium. These had been occurring over the previous several weeks. He had a mostly sedentary lifestyle and a history of syncope with prodromal symptoms, including dizziness, after a period of physical activity. He denied palpitations or dyspnea. He did not smoke or use recreational drugs, and he had no family history of premature coronary artery disease, syncope, sudden cardiac death, or cardiac arrhythmias.