Premature Ventricular Contraction (PVC)

Unblinded, controlled, non-randomized, mechanistic study to determine whether physiological mechanisms underlying PVC are sensitive to adenosine. One hundred subjects undergoing clinically-indicated, standard-of-care cardiac electrophysiology study (EPS) procedure for PVCs will receive adenosine and/or verapamil to learn if their arrhythmias are inducible similarly to sustained ventricular tachycardia.

Premature ventricular complexes (PVCs) are extra, abnormal heart beats arising from the ventricles of the heart and are the most common ventricular arrhythmia. PVCs can be treated with medication or with a procedure called catheter ablation. It is not known which provides a better cure or provides better quality of life. The purpose of this research project is to study the best way to treat PVCs by comparing the use of medication to catheter ablation to assess which approach is better at reducing symptoms and improving quality of life.

Whereas the available evidence mostly supports chronic sleep disruption as a risk factor for incident AF, less is known about the near-term risk of a discrete atrial fibrillation (AF) episode following a night of disrupted or poor-quality sleep. This prospective, randomized, case-crossover study aims to examine the acute effects of sleep disruption on clinically relevant cardiac ectopy pertinent to AF.

The UNIFLECA study is a prospective, single-arm, observational cohort evaluating the efficacy, safety, and tolerability of flecainide (in the form of Sanocard) in adults with frequent idiopathic premature ventricular contractions (PVCs) and suspected PVC-induced cardiomyopathy (PVCi-CMP). Frequent PVCs-defined as a burden \>5% on two separate 24-hour Holter recordings-are increasingly recognized as a cause of reversible systolic dysfunction in patients without structural heart disease. Participants undergo a comprehensive baseline evaluation including echocardiography, occasionally cardiac MRI, and coronary angiography or equivalent testing to confirm the absence of structural abnormalities. Patients are enrolled only if they are ineligible or unwilling to undergo catheter ablation, and have no contraindications to flecainide. Flecainide therapy is initiated at a starting dose of 100 mg/day and titrated up to 200 mg/day, guided by ECG findings, symptom response, and QRS duration. Regular follow-up occurs at three-month intervals over three years, with periodic 24-hour Holter monitoring and assessment of symptoms, LVEF, and adverse events. The primary outcome is the reduction in PVC burden. Secondary outcomes include improvement in LVEF, symptom relief (measured by structured questionnaires), adverse effects, and long-term treatment adherence. The study aims to generate real-world data on the non-invasive management of PVCs with flecainide and explore its role as an alternative to ablation in carefully selected patients.