Clinical Research Directory

Catheter ablation (CA) of premature ventricular complexes (PVCs) will be performed in standard fashion as approved by international guidelines. CA aims to deliver therapeutic energy to the site of origin of the PVCs, rendering the tissue there incapable of causing the arrhythmia. Ablations will be performed under sedation or GA, guided by electroanatomic mapping and cardiac imaging. End point of CA will be abolition of all PVCs (with and without isoprenaline provocation) with a 30-minute waiting period. Occasionally, patients may experience episodes of PVC quiescence and an absence of PVCs on the day of CA. This can be a result of changes in medication, stress, hormones, electrolytes and can be unpredictable. As at least one PVC occurring during the CA is required to perform a CA, an episode of PVC quiescence on the day of the procedure that inhibits the ablation from taking place will not preclude the patient from having a repeat attempt at the CA.

This arm aims to replicate standard of care for patients with PVCs managed by a non-interventional approach, usually encompassing patients who have symptoms and have not previously been prescribed an AAD or BB, being commenced on an AAD and/or a BB. Choice of AAD/BB will be left to primary physician: If deferred to the trial team, clinical protocol suggests sotalol (which has both AAD and BB properties) 80mg twice daily, or a lower dose if indicated. If sotalol is contraindicated, an alternative BB may be initiated using standard doses (metoprolol, atenolol, bisoprolol). Clinicians may consider alternative AAD if BBs are contraindicated. For example, a dihydropyridine calcium channel blocker (verapamil or diltiazem) may be initiated if patient has concurrent asthma. If coronary artery disease and structural heart disease is ruled out, flecainide (class I anti-arrhythmic agent) may be used. As with clinical practice, AAD/BB can be changed at any time depending on clinical response.