Extrasystole is a medical term that describes an abnormal heart rhythm, characterized by a premature contraction of the heart's chambers. The term is also commonly referred to as premature ventricular contractions (PVC) or premature atrial contractions (PAC). Other synonyms that can be used to describe extrasystole include ectopic heartbeat, premature heartbeats, skipped heartbeats, and arrhythmia. The condition is generally harmless and may not require any treatment, but persistent or severe extrasystoles may require medical intervention. Treatments may include medications, lifestyle changes, or procedures to correct underlying heart conditions. It is important to consult a healthcare professional if you experience any unusual heart rhythms or symptoms.