What are the implications of multiple premature ectopic contractions (PVCs) on an electrocardiogram (ECG)?

From the Guidelines

The presence of multiple premature ectopic contractions (PVCs) on an electrocardiogram (ECG) is associated with increased cardiovascular risk and mortality, particularly if frequent, and warrants further evaluation to rule out underlying conditions such as ischemic heart disease or left ventricular dysfunction. This is based on the most recent and highest quality study, which found that frequent PVCs, defined as at least 1 PVC on a 12-lead ECG or >30 PVCs per hour, are associated with increased cardiovascular risk and mortality 1.

Key Findings

• PVCs are common and increase in frequency with age, with approximately 50% of people with or without heart disease having PVCs on longer-term monitoring 1.
• The presence of PVCs on 2 minutes of monitoring in middle-aged patients is associated with increased risk of ischemic heart disease events and mortality, with or without prevalent ischemic heart disease 1.
• Multifocal PVCs are associated with increased risk of death and nonfatal cardiovascular adverse outcomes, including stroke 1.
• Nonsustained ventricular tachycardia (NSVT) is independently associated with increased risk of death and other cardiovascular adverse outcomes, including stroke 1.

Clinical Implications

• The detection of PVCs, particularly if multifocal and frequent, is generally considered a risk factor for adverse cardiovascular outcomes, and such patients should be evaluated to ensure they do not have underlying conditions that warrant further treatment to reduce risk 1.
• Treatment of PVCs with antiarrhythmic medications has not been shown to reduce mortality and may increase the risk of death in certain populations, such as post-myocardial infarction patients or those with reduced left ventricular ejection fraction (LVEF) 1.
• Beta blockers may be considered for treatment of PVCs, but the decision to treat should be individualized based on the patient's underlying condition and symptoms.

Evaluation and Management

• A 12-lead ECG and exercise stress test are recommended as the minimal level of testing to acquire prognostic information in patients with PVCs 1.
• An echocardiogram may also be performed to rule out structural abnormalities, and other imaging studies such as computed tomography or magnetic resonance imaging may be considered in certain cases 1.
• A 24-hour ambulatory monitor may be helpful in determining the frequency and pattern of PVCs, and patients with >2000 PVCs per 24 hours may require annual cardiological evaluation 1.

From the Research

Implications of Multiple Premature Ectopic Contractions (PVCs) on an Electrocardiogram (ECG)

• Multiple PVCs on an ECG can have varying implications, ranging from being asymptomatic to predisposing patients to underlying cardiomyopathy, heart failure, or sudden cardiac death 2, 3.
• A higher burden of PVCs is a risk factor for the development of PVC-induced cardiomyopathy (PIC) 3, 4.
• PVCs can result in symptoms such as palpitations, dyspnea, presyncope, and fatigue, and can also lead to a reduced left ventricular ejection fraction 4, 5.
• The prognosis of patients with PVCs is variable, with an increased PVC frequency potentially being a risk factor for heart failure and death 4, 5.
• Diagnostic testing, including 12-lead ECG, ambulatory monitoring, echocardiogram, and cardiac magnetic resonance imaging, is essential for evaluating the underlying structure and function of the heart in patients with PVCs 3, 4, 5.

Management and Treatment of PVCs

• Management of PVCs depends on the presence and severity of symptoms, as well as the frequency and burden of PVCs 2, 4.
• Patients with no or mild symptoms, a low PVC burden, and normal ventricular function may be best served with simple reassurance 4.
• Medical treatment, including β-blockers or nondihydropyridine calcium channel blockers, or catheter ablation may be considered for patients with symptomatic PVCs or a reduced left ventricular ejection fraction 4, 5.
• Catheter ablation is a highly effective approach to eradicate PVCs, but may confer increased upfront risks 5.

Mapping Strategies for PVCs

• Mapping strategies, including activation, voltage, and pace mapping, are used to visualize the area of earliest activation and to identify the target area for catheter ablation 5.
• A combination of activation and pace mapping is often used to maximize procedure outcome and efficiency 5.
• Voltage mapping plays a primary role in the mapping of substrate-based sustained arrhythmias in patients with underlying structural heart disease 5.