Arrhythmias

We are one of the most active centres in the country in interventional arrhythmia research. In addition to the UKPACE trial, we were a lead recruiting centre in the pan-European CARE-HF trial of cardiac resynchronisation therapy (CRT) for heart failure and the multi-national SAFE-PACE 2 trial of pacing for patients with recurrent falls and carotid sinus hypersensitivity. We were also the principal UK investigator for the multi-national, NIH-funded Home AED trial (N Engl J Med 2008; 358:1793-1804), which assessed the efficacy, in the event of cardiac arrest, of the deployment of automated external defibrillators by spouses or partners in the homes of 7,000 patients after myocardial infarction. Our clinical research has resulted in the first randomised trial demonstrating the benefit of radiofrequency ablation of atrial fibrillation at the time of mitral valve surgery.

We are translating pre-clinical work on electrical restitution of the heart and its relationship to risk of ventricular fibrillation into clinical studies applying high resolution electrical mapping to improve risk stratification of sudden death in post-myocardial infarction patients. This has implications for determining who may benefit from an implantable cardiac defibrillator.

The clinical arrhythmia research programme is complemented by laboratory studies examining the influence of abnormal autonomic activity and ion handling in the initiation and characteristics of ventricular fibrillation. Dr André Ng's group have developed a novel experimental preparation for these studies, which is being widely requested by other groups. Underlying mechanisms such as nitric oxide signalling are being investigated, as well as the interaction between autonomic activity and ischaemia / hypoxia. There is active NIH-funded collaboration with Professor G Salama, Pittsburgh, using optical mapping techniques to examine the autonomic influence on cytoplasmic Ca2+ and action potentials in arrhythmogenesis.