**Question:** What is not true for extrasystole in ventricle:

A. Extrasystole is always a benign condition with no clinical significance.
B. Extrasystoles can occur as a result of autonomic nervous system stimulation.
C. Extrasystoles are always associated with structural heart disease.
D. Extrasystoles are always detected during routine physical examination.

**Correct Answer:** .

**Core Concept:** Extrasystole refers to premature ventricular contractions (PVCs), which are abnormal heartbeats that occur before the expected regular heartbeat. Ventricular extrasystoles typically originate from the ventricles and can be benign or indicate underlying cardiac pathology.

**Why the Correct Answer is Right:** Extrasystole in the ventricle can be benign and have no clinical significance (Option A). However, this is not always true, as extrasystoles may also be related to autonomic nervous system stimulation (Option B). The extrasystole may be caused by various factors, such as emotional stress, physical activity, or medication intake, which can stimulate the autonomic nervous system.

**Why Each Wrong Option is Incorrect:**

- Option C states that extrasystoles are always associated with structural heart disease. While extrasystoles may indicate underlying cardiovascular abnormalities, not all ventricular extrasystoles are caused by structural heart disease (e.g., due to autonomic nervous system stimulation).
- Option D claims that ventricular extrasystoles are always detected during routine physical examination. While a doctor may auscultate for extra heartbeats during a physical examination, extrasystoles can also be identified through various diagnostic methods like electrocardiography (ECG) or Holter monitoring. Therefore, not all cases can be detected during a routine physical examination.

**Clinical Pearl:** It is essential to consider extrasystoles as a benign condition and a possible precursor to structural heart disease. A thorough evaluation with ECG and a detailed history can help differentiate between benign and concerning extrasystoles, guiding management and prognosis.