Boot shaped heart on chest X – ray is seen in-
**Core Concept**
The question is testing the ability to identify a characteristic radiographic sign associated with a specific cardiac condition. A "boot-shaped heart" is a descriptive term used to describe the silhouette of the heart on a chest X-ray, which is indicative of right ventricular hypertrophy.
**Why the Correct Answer is Right**
Right ventricular hypertrophy occurs in conditions that lead to increased resistance or pressure in the right ventricle, such as pulmonary hypertension. The right ventricle becomes thicker and more prominent, causing the cardiac silhouette on a chest X-ray to take on a distinctive "boot-shaped" appearance. This is due to the upward displacement of the apex of the heart and the prominence of the right ventricle.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because left ventricular hypertrophy would not result in a boot-shaped heart on a chest X-ray. Left ventricular hypertrophy would more likely cause an increased cardiac silhouette due to the increased size of the left ventricle.
**Option B:** This option is incorrect because a normal chest X-ray would not show a boot-shaped heart. A normal heart would have a more rounded silhouette.
**Option C:** This option is incorrect because cor pulmonale is a condition characterized by right ventricular hypertrophy, but it is not the only condition that can cause a boot-shaped heart on a chest X-ray. However, cor pulmonale is a specific type of right ventricular hypertrophy caused by pulmonary hypertension.
**Option D:** This option is incorrect because cardiomyopathy would not typically result in a boot-shaped heart on a chest X-ray. Cardiomyopathy can cause a range of changes in the cardiac silhouette, but a boot-shaped heart is not a characteristic feature.
**Clinical Pearl / High-Yield Fact**
A boot-shaped heart on a chest X-ray is a classic sign of right ventricular hypertrophy, which can be caused by a variety of conditions including pulmonary hypertension, congenital heart disease, and chronic lung disease.
**Correct Answer:** C. Cor pulmonale.