From the Guidelines
Premature Ventricular Complexes (PVCs) are considered significant when they comprise more than 15% of the total R-R complexes in a 24-hour period, as indicated by the 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death 1. This threshold is clinically important because PVCs at this frequency are associated with an increased risk of developing cardiomyopathy, heart failure, and other cardiac complications. The 15% cutoff is often used by cardiologists to guide treatment decisions, particularly when considering antiarrhythmic medications or ablation therapy. Some studies suggest that a lower threshold may also be significant, especially in certain populations, but the 15% cutoff is the most widely accepted and evidence-based threshold 1. It is essential to note that the frequency and burden of PVCs can vary significantly between individuals, and the presence of underlying structural heart disease or other comorbidities can impact the clinical significance of PVCs 1. Therefore, patients with PVC burden exceeding this threshold should be evaluated for underlying structural heart disease and may require treatment, especially if they are symptomatic or show evidence of declining left ventricular function. Key factors to consider in the evaluation and management of PVCs include the frequency and burden of PVCs, the presence of underlying structural heart disease, and the patient's symptoms and overall clinical presentation. In general, a comprehensive evaluation, including ambulatory monitoring, echocardiography, and exercise stress testing, is necessary to determine the clinical significance of PVCs and guide treatment decisions. By prioritizing the most recent and highest-quality evidence, clinicians can provide optimal care for patients with PVCs and reduce the risk of adverse outcomes. The evidence-based threshold of 15% PVCs is a critical component of this approach, allowing clinicians to identify patients at increased risk and provide targeted interventions to improve outcomes. Ultimately, the management of PVCs requires a nuanced and individualized approach, taking into account the unique characteristics and needs of each patient. By combining the latest evidence with clinical expertise and patient-centered care, clinicians can optimize outcomes for patients with PVCs and improve overall quality of life.
From the Research
Definition of Significant PVCs
- Significant Premature Ventricular Complexes (PVCs) are generally considered to be those that occur at a frequency of 1% or more of total RR complexes 2.
Percentage of Total RR Complexes
- A study published in the Journal of cardiovascular electrophysiology in 2019 found that patients with frequent PVCs had a burden of ≥ 1% 2.
- Another study published in the Journal of cardiovascular electrophysiology in 2021 found that the median initial PVC burden ranged from 15.5% to 20.6% 3.
- A study published in Heart (British Cardiac Society) in 2019 found that patients with frequent PVCs had a median PVC burden of 18.4% 4.
Clinical Significance
- PVCs can lead to symptoms such as cardiomyopathy and increased mortality 2.
- A study published in The Mount Sinai journal of medicine, New York in 2005 found that mean frequency of PVCs correlates with vulnerability to malignant arrhythmias such as ventricular tachycardia and/or ventricular fibrillation (VT/VF) 5.
Treatment and Management
- Beta-blockers are recommended as first-line therapy to reduce PVC burden 2.
- A study published in JACC. Clinical electrophysiology in 2023 found that catheter ablation (CA) seems superior to antiarrhythmic drug (AAD) therapy for PVC recurrence, frequency, and burden 6.
- A study published in the Journal of cardiovascular electrophysiology in 2021 found that Class I and III antiarrhythmic drugs (AADs) have superior effectiveness for medical therapy in symptomatic patients 3.