Pacing Therapy

This study aims to evaluate whether posterosuperior bundle (PSB) pacing reduces the incidence of atrial fibrillation (AF) in patients with sinus node dysfunction (SND) undergoing pacemaker implantation. Approximately 300 patients will be enrolled and randomized to receive atrial pacing at either the PSB region or the right atrial appendage (RAA). The primary endpoint is the occurrence of AF episodes lasting ≥6 minutes, as detected by device or surface electrocardiogram. Patients will be followed for up to 24 months.

This is a prospective, single-center, non-randomized, within-subject interventional study. The purpose is to compare the immediate effects of different atrial pacing sites on atrial electrical activation, as reflected by P-wave characteristics on surface electrocardiography (ECG). During pacemaker implantation, short-term pacing will be performed sequentially at multiple predefined atrial sites, including the right atrial appendage (RAA), atrial septum, Bachmann's bundle (BB) area, and posterosuperior bundle (PSB) regions. ECG parameters will be recorded at each site to evaluate differences in P-wave duration and morphology.

A randomized, single-blind study comparing two pacing strategies in patients with atrioventricular block requiring permanent pacemaker implantation. This trial evaluates the impact of conduction system pacing (left bundle branch area pacing) versus standard right ventricular pacing on central hemodynamics, cardiac function, and patient quality of life over 12 months. The study will enroll 124 patients from two Estonian tertiary hospitals and measure central systolic arterial pressure as the primary outcome, with secondary assessments of arterial stiffness, echocardiographic parameters, electrical activation patterns, and quality of life scores.

Conduction system pacing is a new way of stimulating the heart using pacemaker wires. Traditional pacemakers stimulate the heart muscle which causes disordered heart beats: the walls of the heart move at different times. This wears down the heart over time. Conduction system pacemakers stimulate the heart's electrical system directly producing natural heart beats that are much less disordered. Unfortunately, these pacemakers can only be implanted by a small group of experts at specialised centres with specialist equipment. This study aims to allow conduction system pacemakers to be offered to any patient at any hospital by simplifying the process of inserting the pacemaker wires and the improving the pacemaker's ability to interpret electrical traces. Firstly, the best locations in the heart for conduction system pacemaker wires using specialised electrical traces, MRI and ultrasound scans will be identified. Features that can be seen on X-ray to guide doctors to these locations will then be identified. Secondly, the investigators will collect electrical information from the pacemaker wires and additional electrical traces to develop an algorithm that can make the interpretation the electrical traces more accurate.

Pace maker implantation after the procedure of TAVR can be estimated at 15% of patients. However, some studies have shown that the conduction disturbances after TAVR could resolve over time, and that roughly between one- and two-thirds of patients who required a permanent pace maker implantation post TAVR were not found to be dependent at subsequent follow-up. This study aims to evaluate a cohort of patients permanently implanted with a pacemaker post-TAVR for high-grade conductive disorders and to describe the prevalence of effective pacemaker stimulation at 1 year follow-up. Secondary objectives include the evaluation of the prevalence of effective stimulation 3 months after implantation of the pace maker , description of the types of conductive disorders associated with atrial and/or ventricular stimulation, description of the initial indication for pacemaker implantation, description of the characteristics of the population with or without stimulation dependency. The objective is to better rationalize indication of permanent stimulation after TAVI