Feeling your heart skip a beat can be an unsettling experience, often leading to concerns about heart health. This sensation, often described as a “skipped beat” or “flutter,” is frequently due to premature ventricular contractions (PVCs). These extra heartbeats are a common type of irregular heart rhythm, often experienced without awareness.
What are Premature Ventricular Contractions?
Premature ventricular contractions (PVCs) are extra heartbeats that originate in the heart’s lower pumping chambers, the ventricles. Normally, the heart’s rhythm is controlled by an electrical signal starting in the upper chambers (atria) and traveling downward. With a PVC, an electrical impulse begins prematurely in the ventricles, disrupting the usual sequence.
This early beat is often followed by a brief pause. The next normal heartbeat can then feel more forceful, leading to the sensation of a “skipped beat” or a strong “thump” in the chest. Many people with PVCs experience no symptoms at all.
Common Causes of PVCs
Many factors can trigger premature ventricular contractions, from lifestyle choices to underlying health conditions. Common lifestyle triggers include stimulants like caffeine, tobacco, and alcohol, which heighten cardiac stimulation. Stress, anxiety, and lack of sleep are also frequently implicated, as they can lead to increased adrenaline. Dehydration and certain over-the-counter medications, such as decongestants, may also contribute.
PVCs can also be associated with various underlying heart conditions, including previous heart attacks, heart failure, and high blood pressure. Electrolyte imbalances, specifically low levels of potassium or magnesium, can affect the heart’s electrical stability and trigger PVCs. Thyroid issues, particularly an overactive thyroid, may also contribute. Despite these potential causes, PVCs often occur in individuals with otherwise healthy hearts without a clear identifiable reason.
Diagnosing PVCs
When a healthcare provider suspects premature ventricular contractions, they typically begin with a physical examination and a review of symptoms and medical history. The primary diagnostic tool is an Electrocardiogram (ECG or EKG), which records the heart’s electrical activity and can detect the extra beats. If PVCs are infrequent, a standard in-office ECG may not capture them.
In such cases, portable ECG devices are often used for longer-term monitoring. A Holter monitor is worn for 24 to 48 hours to continuously record heart activity during daily routines. For less frequent events, an event recorder can be worn for up to 30 days, allowing the individual to activate it when symptoms occur. Further tests, like an echocardiogram to assess heart structure or a stress test to see if PVCs are triggered by exercise, might be recommended if an underlying heart condition is suspected.
When to Be Concerned and Management Approaches
Isolated premature ventricular contractions are generally considered harmless and often do not require specific treatment, especially in individuals without underlying heart disease. However, certain situations warrant closer attention. These include very frequent PVCs (more than 10-15% of all heartbeats in 24 hours), PVCs occurring in runs, or those accompanied by concerning symptoms like dizziness, fainting, or chest pain. PVCs in individuals with pre-existing heart disease, such as heart failure or a history of heart attack, may indicate a higher risk of more serious rhythm problems or weakening of the heart muscle.
Management approaches vary depending on the frequency of PVCs, symptoms, and any underlying heart conditions. For benign cases, lifestyle modifications are often recommended. If lifestyle changes are insufficient or PVCs are bothersome, medications may be prescribed. Beta-blockers or calcium channel blockers, which help slow the heart rate and reduce the force of contractions, are common first-line treatments. Antiarrhythmic drugs may also be considered for more severe cases.
In rare instances, particularly for very frequent PVCs that lead to a weakened heart muscle or are unresponsive to medication, a catheter ablation procedure might be performed. This minimally invasive procedure uses heat or cold energy to create tiny scars in the heart, blocking irregular electrical signals. Consulting a healthcare professional is important for personalized advice and to determine the most appropriate management strategy.