USMLE (United States Medical Licensing Examination) Step 1 Practice Exam

How can acute rheumatic fever lead to chronic complications in the heart?

1. Pulmonary fibrosis

2. Tricuspid valve insufficiency

3. Prolonged QT interval

4. Mitral regurgitation or stenosis

The correct answer is: Mitral regurgitation or stenosis

Acute rheumatic fever is a serious inflammatory condition that can develop after untreated streptococcal throat infections. One of the key long-term complications of this condition is the impact it can have on the heart, specifically leading to chronic rheumatic heart disease. The correct answer highlights that mitral regurgitation or stenosis can occur as a result of acute rheumatic fever. The inflammatory process during the fever can cause damage to the heart valves, particularly the mitral and aortic valves. This can result in either regurgitation—where the valve fails to close properly, allowing blood to flow backward—or stenosis, where the valve becomes narrowed, restricting blood flow. Over time, these valve injuries can lead to significant heart dysfunction and symptoms such as heart failure, as well as an increased risk for complications such as atrial fibrillation and ultimately, infective endocarditis. Other options provided do not represent primary complications of acute rheumatic fever. For instance, pulmonary fibrosis is typically associated with conditions like interstitial lung disease rather than rheumatic fever. Tricuspid valve insufficiency, although it can develop, is not as directly linked to rheumatic fever as the mitral valve involvement is. A prolonged QT interval is usually