Almost all of us will have ventricular ectopic beats (also known as premature ventricular contractions or PVCs). As the name implies these are extra beats of the heart which originate in the bottom chambers of the heart (the ventricles). A normal heart beat originates from the top of the heart (the atria). Ventricular ectopic beats occur prematurely and cause the heart to beat in a different way for that beat.
In the majority of patients, who have a structurally normal heart ventricular ectopics are almost always benign and don’t require any treatment unless they are causing symptoms. In the much smaller group of people who have evidence of structural heart disease, ventricular ectopics can be a marker of increased risk.
Many patients have no symptoms. Others may experience a sensation of fluttering or butterflies in the chest. Some people experience a sensation of their heart stopping or skipping a beat, which can understandably be worrying. This sensation occurs because after an ectopic beat, the heart beat cycle resets. This is preceded by a short pause which may feel as if your heart momentarily stops. Other common symptoms are a sensation of dizziness, a ‘thump’ in the chest or shortness of breath. Symptoms are often experienced at night or when resting. The reason for this is that your heart rate is lower at rest and when you are sleeping allowing the ectopic beats more time to occur.
Many patients will experience symptoms sporadically or with no particular trigger. Sometimes patients will experience symptoms intermittently, with weeks or months between episodes.
Caffeine in coffee and energy drinks, alcohol and tiredness or disturbed sleep are by far the most common triggers. Indeed some patients will notice an immediate improvement in their symptoms once these are eliminated. Hormonal changes such as those seen in pregnancy or during the menopause may also cause ventricular ectopics. Occasionally viral infections of the lining of the heart ( myocarditis) may cause ectopics.
Your cardiologist will take a detailed history and examination. It is important to establish if there is a potential underlying cause, lifestyle factors or a family history of heart disease. Investigations are performed to rule out an underlying cause and to gather more information. Patients will have an electrocardiogram (ECG) which provides a general overview of the heart. if ectopics are frequent an echocardiogram (heart ultrasound) or Cardiac MRI scan may be performed to confirm that your heart has a normal structure and function and to rule out heart muscle disease (cardiomyopathy). Blood tests are performed to look for other potential causes such as abnormal electrolyte levels (eg sodium and potassium) and thyroid function.
Your specialist may also perform a continuous ECG monitor to establish the ‘ectopic burden’ This is a measure of the percentage of ectopic beats when compared to all your heart beats. There is emerging evidence that a high ectopic burden (10-30%) may potentially affect the way that your heart beats over time if left untreated. The ECG monitor also helps determine if the ectopic beats are originating from one site or from multiple sites which helps guide treatment
In many patients, reassurance and understanding that the condition is likely to be benign is all that is required.
Simple lifestyle measures such as reducing caffeine and alcohol intake, smoking cessation, improved sleeping habits and stress reduction will be sufficient to considerably improve or eliminate symptoms.
Medications may also be used to suppress the ectopics and improve symptoms. If the ectopic beats are originating from one site, then a treatment called catheter ablation may be used. This procedure involves passing fine wires into the heart from the top of the leg in a minimally invasive/non-surgical procedure, A ‘virtual’ 3D geometry of your heart is created using a computer mapping system. Using electrical signals from within your heart, the exact site of origin of the ectopic beats is located and high frequency energy is delivered at this site to eliminate the abnormal beats. The procedure is minimally invasive and does not involve surgery. Most patients are discharged home on the same day.
Catheter ablation is very safe and carries a very high success rate in appropriate patients of over 85%. The risks from the procedure are small and are in the region of 1-2%. These risks include vascular complications (bleeding from the leg) and less frequently bleeding around the heart. Bleeding around the heart is usually treated very effectively with a small drain inserted from the front of the chest, without requiring an operation. Very occasionally emergency surgery or a permanent pacemaker is required as a result of treatment.