Premature Ventricular Contraction (PVC)

Premature Ventricular Contractions (PVCs) are extra heartbeats that begin in the heart's lower chambers, called the ventricles. These extra beats disrupt the normal heart rhythm and can cause a feeling of a skipped or extra heartbeat. The condition affects the cardiovascular system and may be noticed as palpitations or an irregular heartbeat. While often harmless, frequent PVCs can sometimes indicate underlying heart problems. The main health impact is on the heart's ability to pump blood efficiently, especially if PVCs occur very frequently or in certain patterns. PVCs can occur in healthy individuals or those with heart disease. Understanding PVCs helps in evaluating heart rhythm abnormalities and their potential risks.

Premature Ventricular Contraction (PVC) is defined as an early depolarization originating from an ectopic focus within the ventricular myocardium, causing a premature and abnormal ventricular contraction. The core pathology involves abnormal automaticity or triggered activity in ventricular myocytes, often due to ischemia, electrolyte imbalances, or structural heart disease. PVCs disrupt the normal cardiac conduction system, leading to a wide and bizarre QRS complex on electrocardiogram (ECG) without a preceding P wave. They are significant because frequent or multifocal PVCs can precipitate ventricular tachyarrhythmias or indicate underlying myocardial pathology. PVCs may be isolated or occur in patterns such as bigeminy or couplets. Their presence can affect cardiac output and may cause symptoms like palpitations or syncope in some patients.