What is the etiology of Premature Ventricular Contraction (PVC)?

From the Guidelines

PVCs can arise from various cardiac and non-cardiac causes, including structural heart disease, electrolyte abnormalities, and stimulant use, and understanding the underlying etiology is crucial for appropriate management. The etiology of PVCs is multifactorial, and common cardiac causes include coronary artery disease, cardiomyopathy, myocarditis, and valvular heart disease, as well as heart failure and previous myocardial infarction with resulting scar tissue, which can create arrhythmogenic substrates 1. Non-cardiac causes of PVCs include electrolyte abnormalities, such as hypokalemia and hypomagnesemia, hyperthyroidism, caffeine, alcohol, nicotine, and certain medications, including some antiarrhythmics, antihistamines, and antipsychotics 1. Additionally, stimulant drugs like cocaine and amphetamines can trigger PVCs, and psychological stress and anxiety may also precipitate PVCs in susceptible individuals 1. Idiopathic PVCs, which occur in patients without structural heart disease, represent a significant percentage of cases and often originate from the right ventricular outflow tract or left ventricular fascicles 1.

Some key points to consider in the etiology of PVCs include:

• Structural heart disease, such as coronary artery disease and cardiomyopathy, can increase the risk of PVCs 1
• Electrolyte abnormalities, such as hypokalemia and hypomagnesemia, can trigger PVCs 1
• Stimulant use, including caffeine, alcohol, and nicotine, can precipitate PVCs 1
• Psychological stress and anxiety may also contribute to the development of PVCs 1
• Idiopathic PVCs can occur in patients without structural heart disease and may originate from the right ventricular outflow tract or left ventricular fascicles 1

Treating the root cause of PVCs, such as correcting electrolyte imbalances or reducing stimulant intake, may eliminate PVCs without requiring specific antiarrhythmic therapy. In some cases, frequent PVCs can produce a reversible form of left ventricular dysfunction, and catheter ablation may be an effective treatment option for PVC-induced cardiomyopathy 1. However, it is essential to determine the underlying etiology of PVCs to provide appropriate management and prevent potential complications, such as increased risk of ischemic heart disease events and mortality, as well as stroke 1.

From the Research

PVC Etiology

• Premature ventricular contractions (PVCs) are arrhythmias with a presentation ranging from asymptomatic and benign to symptomatic, frequent, and capable of inducing cardiomyopathy 2.
• The presence of PVCs is independently linked to an increased risk of stroke and sudden cardiac death 2.
• PVCs can be representative of underlying coronary artery disease, hypertension, or left ventricular hypertrophy, as shown in work from the late 1970s-1980s 2.
• The etiology of PVCs can also be related to underlying structural heart disease (SHD), which may indicate an increased risk of sudden death 3.
• High PVC burden may induce cardiomyopathy and left ventricular (LV) dysfunction or worsen underlying cardiomyopathy 3.
• Sometimes PVCs may be a marker of underlying pathophysiologic processes such as myocarditis 3.

Risk Factors

• The presence or absence of structural heart disease, PVC burden, and other factors can influence the prognosis of PVCs 4.
• PVC characteristics, such as frequency and burden, can also impact the presentation and prognosis of PVCs 4.
• Patient comorbidities, such as hypertension and coronary artery disease, can also play a role in the etiology and prognosis of PVCs 2, 4.

Diagnosis and Treatment

• Diagnosis of PVCs can involve physical examination, electrocardiogram, ambulatory monitoring, exercise testing, echocardiography, cardiac magnetic resonance imaging, coronary angiography, and electrophysiology study 3.
• Treatment of PVCs can include lifestyle modification, addressing reversible causes, pharmacotherapy, or catheter ablation 4, 3.
• Antiarrhythmic drugs, such as beta-blockers and dihydropyridine calcium channel blockers, are commonly used to treat PVCs, but their efficacy can vary 5, 6.
• Flecainide, propafenone, and sotalol are examples of antiarrhythmic drugs that can be used to treat PVCs, with flecainide being the most effective in achieving complete/near complete or significant PVC burden reduction 5.