**Question:** Regarding HOCM (Hypertrophic Cardiomyopathy), all are true except

A. HCM is a genetic disorder caused by mutations in cardiac myosin-binding protein C (MYBPC3) gene.
B. HCM typically affects the left ventricle (LV) and can cause left ventricular outflow tract (LVOT) obstruction.
C. HCM is primarily a disease of the elderly, with a median age of presentation around 40 years.
D. HCM is associated with increased risk of sudden cardiac death due to ventricular arrhythmias.

**Core Concept:**
Hypertrophic Cardiomyopathy (HCM) is a genetic disorder characterized by unexplained myocardial hypertrophy, leading to left ventricular outflow tract (LVOT) obstruction and cardiovascular complications. Mutations in cardiac myosin-binding protein C (MYBPC3) gene are responsible for the disease. The condition primarily affects the left ventricle (LV), and can cause LVOT obstruction. The disease usually presents in young adults or middle-aged individuals, with a median age of presentation around 40 years.

**Why the Correct Answer is Right:**

The correct answer (D) is right because HCM is indeed associated with increased risk of sudden cardiac death due to ventricular arrhythmias. Ventricular arrhythmias occur because of the abnormal myocardial hypertrophy and disarray, which can lead to re-entrant circuits, and may result in life-threatening events. However, options A, B, and C are incorrect:

**Why Option A is Incorrect:**
Option A states that HCM is a disease of the elderly. Although HCM can present at any age, the median age of presentation is around 40 years, making option A incorrect as it oversimplifies the disease presentation.

**Why Option B is Incorrect:**
Option B states that HCM primarily affects the right ventricle (RV). In reality, HCM primarily affects the left ventricle (LV), which is why this option is incorrect.

**Why Option C is Incorrect:**
Option C claims that HCM is a disease of the elderly. As mentioned earlier, HCM can present at any age, making this option incorrect in stating that it is primarily a disease of the elderly.

**Why Option D is Correct:**
Option D highlights the increased risk of sudden cardiac death due to ventricular arrhythmias in HCM patients. Ventricular arrhythmias are a result of the abnormal myocardial hypertrophy and disarray, which can lead to re-entrant circuits, and may result in life-threatening events.

**Clinical Pearls:**
HCM is a genetic disorder with autosomal dominant inheritance and can affect individuals of any age group. The disease leads to left ventricular hypertrophy and can result in LVOT obstruction, arrhythmias, and heart failure. Early diagnosis and management can improve prognosis and reduce the risk of sudden cardiac death.

**Why the Incorrect Options are Unrelated:**

**Option A:** This option incorrectly associates HCM with the right ventricle, which is not the primary affected chamber in HCM. The primary involvement is the left ventricle, as indicated by option