All questions of Cardiology for PLAB/UKMLA Exam

PVC is a relatively frequent occurrence where the heartbeat originates from Purkinje fibres in the ventricles instead of the SA node. The electrical activities of the heart, as recorded by the electrocardiogram, enable a PVC to be easily differentiated from a normal heartbeat, appearing as a broad complex qRS.

• Although a PVC can indicate reduced oxygenation to the myocardium, they are often benign and may occur in otherwise healthy hearts.
• The prevalence of PVCs tends to increase with age.
• A PVC may be experienced as a 'skipped beat' or sensed as palpitations in the chest.

In a PVC, the ventricles contract prior to the atria optimally filling the ventricles with blood, leading to inefficient circulation. However, isolated PVC arrhythmias generally do not present a risk and can be asymptomatic in healthy individuals.