Beating, Fast and Slow

Abstract

A 52-year-old man presented to his primary care physician with a 2-week history of exertional chest discomfort, described as a sensation of fullness in the center of his chest without radiation, and dyspnea. He reported not having these symptoms at rest. He had no light-headedness or syncope. Exertional chest discomfort and dyspnea in this age group are most worrisome for cardiac causes, particularly myocardial ischemia. Other cardiac diseases that need to be considered are bradyarrhythmias, heart failure due to cardiomyopathy, valvular heart disease, and acute myocarditis or pericarditis. The patient should be asked about symptoms that would suggest recent viral illness. Other possible causes are pulmonary disease (e.g., chronic obstructive pulmonary disease, reactive airway disease, and interstitial lung disease) and systemic causes that might contribute to ischemia independent of coronary artery disease, such as anemia and hyperthyroid-ism. The subacute nature of the symptoms makes pulmonary embolism and aortic dissection less likely. The patient had a history of type 2 diabetes mellitus, hypertension, dyslipidemia, and obstructive sleep apnea, for which he used continuous positive airway pressure. He had no known coronary artery disease. He reported no nausea, vomiting, edema in the legs or feet, or recent fevers or viral illnesses. His medications were aspirin, ramipril, atorvastatin, metformin, and glyburide. He did not smoke, drank alcohol rarely, and reported no illicit-drug use. Because his father had received a diagnosis of hypertrophic cardiomyopathy, the patient had undergone screening echocardiogra-phy 3 years previously, which had revealed mild left ventricular hypertrophy but otherwise normal cardiac structure and function. He had no family history of prema-ture coronary artery disease. Ischemia resulting in angina pectoris remains the most likely cause, given the patient's history of diabetes mellitus and other cardiovascular risk factors. The family history raises concern about hypertrophic cardiomyopathy, but his fairly recent echocardiogram makes this condition less likely. Symptomatic bradycardia, an inability to increase heart rate with exercise, or both should also be considered.