Among structural causes of syncope, which is most common in the elderly population?

Among structural causes of syncope, which is most common in the elderly population?

• A. Hypertrophic Cardiomyopathy
• B. Pulmonary Embolism
• C. Aortic Stenosis
• D. Myocardial Infarction

Answer: (C)

In older adults, the most common structural cause of syncope is aortic stenosis due to calcific degeneration of the aortic valve. The narrowing creates a fixed outflow obstruction, so the heart cannot increase the stroke volume during exertion. As a result, during activity the blood pressure may fail to rise adequately, cerebral perfusion drops, and fainting occurs. This pattern fits the elderly best because degenerative calcification of the aortic valve becomes more prevalent with age. Other options—such as hypertrophic cardiomyopathy (more typical in younger people with dynamic outflow obstruction), pulmonary embolism, or myocardial infarction—are either less common structural causes in the elderly or present with different acute patterns rather than a chronic, fixed obstruction.

In older adults, the most common structural cause of syncope is aortic stenosis due to calcific degeneration of the aortic valve. The narrowing creates a fixed outflow obstruction, so the heart cannot increase the stroke volume during exertion. As a result, during activity the blood pressure may fail to rise adequately, cerebral perfusion drops, and fainting occurs. This pattern fits the elderly best because degenerative calcification of the aortic valve becomes more prevalent with age. Other options—such as hypertrophic cardiomyopathy (more typical in younger people with dynamic outflow obstruction), pulmonary embolism, or myocardial infarction—are either less common structural causes in the elderly or present with different acute patterns rather than a chronic, fixed obstruction.