Premature Atrial Contractions Explained
A Premature Atrial Contraction (PAC) occurs when an electrical impulse originates in the heart’s upper chambers, called the atria, earlier than the next expected normal heartbeat. This causes the atria to contract prematurely, disrupting the heart’s regular rhythm. A brief pause often follows this early contraction before the heart resumes its normal beat.
Individuals often describe PACs as a “flutter” in the chest or a feeling that the heart has “skipped a beat.” It can also feel like a brief “thump” as the heart adjusts its rhythm after the premature contraction.
Premature Ventricular Contractions Explained
A Premature Ventricular Contraction (PVC) involves an electrical impulse starting in the heart’s lower chambers, known as the ventricles, before the anticipated regular beat. This leads to an early contraction of the ventricles, momentarily interrupting the normal cardiac rhythm. A compensatory pause frequently follows as the heart resets itself.
People commonly report PVCs as a “strong beat,” a “flip-flop” sensation, or a feeling of the heart “pounding” in their chest. The experience can also be described as a “skipped beat,” similar to PACs, but often with a more pronounced feeling due to the powerful contraction of the ventricles.
What Causes These Extra Beats?
Various factors can contribute to extra heartbeats. Lifestyle elements such as caffeine, alcohol, or nicotine can act as triggers. Stress, anxiety, and insufficient sleep are also frequently associated with an increased incidence of PACs and PVCs, as they can heighten the body’s overall excitability.
Certain medical conditions and medications may also provoke extra beats. Electrolyte imbalances, particularly low potassium or magnesium levels, can disrupt the heart’s electrical stability. An overactive thyroid or high blood pressure can also contribute. Some over-the-counter or prescription medications can sometimes induce premature contractions. Frequently, however, these extra beats occur in individuals with no identifiable cause and an otherwise healthy heart.
Detecting and Evaluating Extra Beats
When extra heartbeats are suspected, healthcare professionals typically begin with a physical examination and an electrocardiogram (ECG or EKG), which records the heart’s electrical activity. For intermittent extra beats, a Holter monitor (worn for 24 to 48 hours) or an event monitor (worn for longer periods, activated by the patient when symptoms occur) may be used to continuously record heart rhythms.
Upon detection, a doctor evaluates the extra beats’ frequency, patterns, and association with symptoms like dizziness or chest pain. The presence of underlying heart disease is also assessed, as this can significantly influence interpretation. While isolated PACs and PVCs are often benign, very frequent occurrences, those appearing in runs, or those accompanied by concerning symptoms may warrant further investigation. Consulting a healthcare professional is advisable if new or worsening symptoms like chest discomfort, shortness of breath, or lightheadedness occur, or if extra beats significantly impact daily life.
Managing Extra Heartbeats
For many individuals experiencing PACs and PVCs, particularly those without underlying heart disease and minimal symptoms, specific medical treatment is often unnecessary. The primary approach focuses on lifestyle modifications to help reduce the frequency of these extra beats. Limiting or avoiding triggers such as caffeine, alcohol, and nicotine can be beneficial.
Implementing stress management techniques and ensuring adequate sleep are important strategies that can help stabilize heart rhythm. If extra beats are frequent, bothersome, or associated with underlying conditions, medical interventions may be considered. This can involve addressing medical issues like electrolyte imbalances or thyroid dysfunction. Medications like beta-blockers may be prescribed to reduce frequency and alleviate symptoms. In rare instances of very frequent and problematic extra beats, catheter ablation might be considered to eliminate the source of abnormal electrical signals.