Heart Palpitations: Why Your Heart Skips a Beat

Heart palpitations — the awareness of your heartbeat being irregular, too fast, or unusually forceful — are one of the most common reasons people visit cardiologists. The vast majority are harmless, but some patterns require evaluation. What Causes Palpitations Premature Ventricular Contractions (PVCs) are the most common cause. These extra heartbeats originate from the ventricles and create a sensation of a "skipped" beat followed by a harder-than-normal beat. Nearly everyone has occasional PVCs. Caffeine, alcohol, nicotine, and stimulant medications can trigger palpitations by increasing heart rate and excitability. Stress and anxiety activate the sympathetic nervous system, releasing adrenaline that increases heart rate and force. Dehydration and electrolyte imbalances (particularly low potassium or magnesium) affect the heart's electrical system. Hormonal changes during menstruation, pregnancy, and menopause can trigger palpitations. Thyroid disorders — both overactive and underactive — can cause heart rhythm disturbances. When Palpitations Are Concerning Most isolated palpitations are benign. However, seek prompt evaluation if palpitations are accompanied by: fainting or near-fainting, chest pain or pressure, severe shortness of breath, lasting more than a few minutes, or occurring with exercise. These may indicate atrial fibrillation, supraventricular tachycardia, or other arrhythmias that benefit from treatment.