Clinical Research Directory

Physical Impairments in Premature Ventricular Complex

Premature ventricular complexes may be observed in individuals without underlying disease due to factors such as physical inactivity, advanced age, smoking, male sex, and psychosocial disturbances, and in some cases may result in sudden cardiac death. Therefore, the aim of this study is to investigate respiratory function, respiratory muscle strength, cough strength, handgrip strength, physical activity level, and quality of life in individuals with premature ventricular complexes.

Catheter Ablation Versus Anti-arrhythmic Drugs for Premature Ventricular Complexes

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.

Sustained Auricular Nerve Stimulation for PVC Suppression

Non-invasive vagus nerve stimulation has been clinically tested for the treatment cardiac arrhythmias. However, prior studies have shown mixed results-possibly in part due to inadequate stimulation duration. Therefore, we have designed an investigator-initiated early feasibility study to evaluate safety, tolerability, and compliance with prolonged, nocturnal auricular nerve stimulation using the Parasym device.

TAES for FPVCs: a Pragmatic, Randomized Controlled Trial

This prospective, randomized controlled trial aims to evaluate the efficacy and safety of Transcutaneous Auricular Vagus Nerve Stimulation (TAVNS) for patients with frequent premature ventricular coomplexes (FPVCs). Ninety participants will be randomized to TAVNS group and sham-TAVNS group with the ratio of 1:1. They will receive TAVNS plus usual care or sham-TAVNS plus usual care for 6 weeks, and then be followed up for 12 weeks after the treatment. The primary outcome was the proportion of participants with a 50% decrease of the 24 hour (24h) premature ventricular complexes (PVCs) after 6-week treatment. Secondary outcomes include the proportion of participants with a 75% decrease of the 24h-PVCs; the decrease from baseline of 24h-PVCs, total 24h-heartbeat, and the frequency of supraventricular arrhythmia; the score change from baseline in PVCs-related symptoms; the score change from baseline in SAS and SDS. Subgroup analyses will be performed in age, gender, and the severity of PVCs. Safety assessment will be documented during the whole trial.

Flecainide in Idiopathic Premature Ventricular Contractions and Related Cardiomyopathy

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.

Transcutaneous Vagus Nerve Stimulation for Ventricular Arrhythmias

Ventricular arrhythmias are abnormal heart rhythms that arise from the bottom chambers of the heart. They can cause debilitating symptoms when they occur intermittently (these are called premature ventricular ectopics or PVCs) and can be life-threatening when they occur continuously (called ventricular tachycardia or VT). These are the most common causes of sudden cardiac death, especially in patients with pre-existing heart disease. They can be a result of overactivation of the sympathetic nervous system, and in extreme circumstances, surgery to cut the nerve may be needed. A novel approach to target this nervous system using a transcutaneous electrical nerve stimulator (TENS) machine has successfully treated arrhythmias that come from the top chambers of the heart (atrial fibrillation). An ear clip is applied for an hour per day connected to a device (smaller than a phone) that can activate the parasympathetic nervous system (that counteracts the sympathetic nervous system). This is called Low-Level Tragus Stimulation (LLTS). Because it has been used for epilepsy for decades, we have evidence of a very high safety profile and tolerability. We plan to enrol 72 patients, 34 with many PVCs and 38 with VT, and randomise them to either first receive LLTS or first receive sham treatment (this will appear the same to the patient and researchers but without any meaningful vibrations being emitted in the sham group). Each patient will then swap over to the other treatment. We will compare whether the LLTS reduces the amount of ventricular arrhythmias during compared to the amount during the sham treatment period. We will use Holter monitors to measure the amount of PVCs after each period in the PVC group. VT patients have an implantable defibrillator that continuously monitors for VT episodes in this group. We will only enrol adults who can give informed consent, and study participation will not interfere with a patient's clinical treatment.

WHEN DO WE HAVE to PERFORM CARDIAC MAGNETIC RESONANCE in PATIENTS REFERRED for PREMATURE VENTRICULAR COMPLEXES by THEIR CARDIOLOGISTS

Premature ventricular complexes (PVC) are a common entity affecting approximatively 20% of the general population. It can be discovered incidentally on electrocardiogram (ECG) or associated with symptoms with a wide spectrum from palpitations, chest pain, to syncope. The initial and non invasive assessment includes holter ECG monitoring, a transthoracic echocardiography (TTE) and an exercise stress test to rule out structural heart disease (SHD), and referred to as benign or "idiopathic" ventricular arrhythmias (IVA). However, these exams may fail to identify subtle myocardial abnormalities such as arrhythmogenic right ventricle dysplasia (ARVD), apical hypertrophic cardiomyopathy, healed myocarditis, ischemic or non-ischemic cardiomyopathies. Cardiac magnetic resonance (CMR) imaging is the gold standard modality to assess regional and global ventricular function. It is also a unique modality to non-invasively detect myocardial edema, myocardial fatty replacement, focal and diffuse fibrosis and could potentially identify SHD in patients with PVC. However, the role of CMR is uncertain, recommended in case of atypical presentation or when the initial assessment can't exclude a cardiomyopathy (recommendations class IIa). This study sought to determine whether and when CMR can be performed to provide diagnosis or prognostic information complementary to initial assessment in patients referred for PVC by their cardiologists.