In a sudden death scenario in a middle-aged patient with known heart disease, which is the most likely cause?

• A. Ischemic heart disease (MI)
• B. HOCM
• C. Pulmonary embolism
• D. Aortic regurgitation

Answer: (A)

The main idea here is that in a middle-aged person with known heart disease, sudden death is most often caused by a lethal ventricular arrhythmia triggered by acute myocardial ischemia from coronary artery disease. When an acute myocardial infarction occurs, the resulting electrical instability of the heart frequently degenerates into ventricular fibrillation or other fatal arrhythmias, leading to sudden death. Hypertrophic obstructive cardiomyopathy tends to be a leading cause in younger people, so in a middle-aged patient with established CAD, MI is the likeliest culprit. Pulmonary embolism and acute aortic regurgitation can cause sudden collapse, but they are less common in this context as the primary cause compared to an acute MI.