Long-term effects of dual-chamber pacing with periodic echocardiographic evaluation of optimal atrioventricular delay in patients with hypertrophic cardiomyopathy >50 years of age.

Various treatment modalities have been introduced to reduce the subaortic pressure gradient in patients with obstructive hypertrophic cardiomyopathy, including pacemaker insertion. Complete ventricular capture during pacing is essential and requires optimization of the atrioventricular interval (AVI). In this study, a protocol using echocardiographic examination assessing the changes in the left ventricular outflow tract (LVOT) gradient in different AVIs, pacing rates, and pacing modes was used for optimal pacemaker programming.