Transvenous endocardial conduction system pacing in patients with a Fontan operation

Ventricular pacing in patients with a Fontan operation is associated with poor outcomes.1 Moreover, delivering ventricular pacing is challenging; it is traditionally performed with epicardial leads, where dense epi-pericardial scar tissue can limit site selection for optimal electromechanical synchrony and can result in suboptimal acute lead function and decreased lead longevity. The advent of conduction system pacing (CSP) in patients with biventricular anatomy has generated a flurry of research in the past 10–20 years, leading to widespread acceptance because of superior systolic function and heart failure outcomes compared with other pacing techniques.