From the Guidelines
High burden PVC is typically defined as PVCs comprising more than 15% of total heartbeats, as stated in the 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death 1. This condition is clinically significant because a high PVC burden can lead to cardiomyopathy (weakening of the heart muscle), heart failure, and increased risk of sudden cardiac death in some patients.
Key Points
- High burden PVC can be a reversible cause of left ventricular (LV) dysfunction that can be effectively treated with catheter ablation, as shown in a prospective study where ablation was completely successful in 80% of patients 1.
- Treatment options include beta-blockers, calcium channel blockers, or antiarrhythmic medications, with catheter ablation considered for patients with very symptomatic or refractory cases 1.
- The underlying mechanism involves abnormal electrical impulses from the ventricles that disrupt the heart's normal rhythm, often due to increased automaticity, triggered activity, or reentry circuits in the ventricular tissue.
Considerations
- The definition of high burden PVC may vary, but the 2017 AHA/ACC/HRS guideline provides a clear threshold of more than 15% of total heartbeats 1.
- The European Society of Cardiology (ESC) guidelines also support the consideration of catheter ablation for patients with frequent symptomatic PVC or NSVT, and for those with LV dysfunction associated with PVCs 1.
- The choice of treatment should be individualized based on the patient's symptoms, LV function, and other clinical factors, with a focus on reducing morbidity, mortality, and improving quality of life.
From the Research
Definition of High Burden of Premature Ventricular Contractions (PVCs)
- A high burden of PVCs is typically defined as more than 20% of all beats 2
- This definition is based on studies that have shown a significant association between high-burden PVCs and heart failure (HF) 2
- Other studies have used different thresholds, such as more than 10% or 5% of all beats, to define a high burden of PVCs 3, 4
Characteristics of High-Burden PVCs
- High-burden PVCs may be an important determinant of heart failure (HF) in patients presenting for PVC ablation 2
- Patients with high-burden PVCs have a three-fold greater odds of HF and 10-fold greater odds of having a first-degree family member with sudden death 2
- The prevalence and characteristics of high-burden PVC patients outside the setting of PVC ablation remain unknown 2
Diagnosis and Evaluation of High-Burden PVCs
- A 24-hour Holter monitor is typically used to quantify PVC burden 5, 3, 2, 4
- The number of PVCs on a 12-lead electrocardiogram (ECG) can be used as a predictor of high-burden PVCs 2
- Patients with symptoms such as palpitations, chest pain, dizziness, or shortness of breath should undergo workup for PVCs, regardless of age 4