Left cardiac border bulge can be seen in all, except –
**Core Concept**
A left cardiac border bulge can be observed in various conditions that affect the heart's contour or the surrounding structures. This phenomenon is often a result of an abnormality in the cardiac silhouette or the mediastinal structures adjacent to the heart.
**Why the Correct Answer is Right**
The left cardiac border bulge is typically seen in conditions that cause left atrial enlargement or left ventricular hypertrophy. The left atrium receives oxygenated blood from the lungs and pumps it into the left ventricle. When the left atrium is enlarged, it can cause a bulge in the left cardiac border due to its increased size. This is often associated with conditions such as mitral stenosis or left ventricular hypertrophy due to hypertension.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided, but typically, conditions such as left ventricular aneurysm or left atrial myxoma can also cause a left cardiac border bulge.
**Option B:** This option is not provided, but conditions such as right heart enlargement or pulmonary artery aneurysm can cause a right or anterior cardiac border bulge, not a left cardiac border bulge.
**Option C:** This option is not provided, but conditions such as left atrial diverticulum or left ventricular diverticulum can also cause a left cardiac border bulge.
**Option D:** This option is not provided, but conditions such as right atrial enlargement or right ventricular hypertrophy can cause a right or anterior cardiac border bulge, not a left cardiac border bulge.
**Clinical Pearl / High-Yield Fact**
A left cardiac border bulge can be a sign of left atrial enlargement, which is often associated with mitral stenosis. Remember the "5 S's" of mitral stenosis: sinus tachycardia, shortness of breath, syncope, sacral edema, and sudden death.
**Correct Answer:**