Pacing

The PROTECT-HF multi-centre randomised controlled trial will compare two different pacing approaches for treating patients with slow heart rates. In it the investigators will compare a long-standing standard approach for pacing; right ventricular pacing, with a new form of pacing, physiological pacing (His and Left bundle area pacing) in 2600 patients. Patients will be allocated at random to receive either right ventricular pacing or physiological pacing. Endpoint measurements will be undertaken at baseline, and at six-monthly intervals post-randomisation. Treatment allocation will be blinded to the endpoint assessor and the patient. Recruitment and pacemaker implantation will be carried out at each participating centre. The primary analysis will be intention to treat. The investigators will also perform an on-treatment analysis. 2048 patients are needed to detect the expected effect size with 85% power. A total of 2600 patients will be recruited to allow for patient drop-out and crossover. 500-patient sub-study will assess within patient, and between groups, echocardiographic changes over a 24-month period to try and improve mechanistic understanding of PICM (Pacing Induced Cardiomyopathy).

This is a multicenter, prospective, observational study ,the aim of this study is to find factors affecting selection of double-chamber leadless pacemaker in patients with atrioventricular block and ambulatory atrioventricular synchronous pacing status over time using a leadless ventricular pacemaker.

Heart failure with preserved ejection fraction (HFpEF) is characterised by impaired diastolic function. A recent clinical trial has demonstrated multiple beneficial outcomes in HFpEF patients receiving personalised accelerated pacing from indwelling permanent pacemakers, including symptomatic improvement, objective reductions in NT-proBNP level and AF-burden. The investigators aim to determine the underlying mechanisms behind these documented effects, to investigate the acute intracardiac haemodynamic response to temporary multisite pacing in HFpEF participants and to gain further mechanistic insight with additional haemodynamic, electrical and echocardiographic data collection during temporary pacing in this cohort. This will all provide valuable information towards new potential targets of therapy.