Visualization of tricuspid valve annulus for implantation of His bundle pacing in patients with symptomatic bradycardia.

BACKGROUND: His bundle pacing (HBP) is a physiological pacing modality, but HBP implantation remains a challenge. OBJECTIVE: This study explored the feasibility of using visualization of the tricuspid valve annulus (TVA) to locate the site for HBP. METHODS: During the lead placement in eight patients with symptomatic bradycardia, the TVA and tricuspid septal leaflet was revealed by contrast injection in the right ventricle under the fluoroscopic right anterior oblique view, and the target site for HBP was identified near the intersection of the tricuspid septal leaflet and the interventricular septum. On the basis of the imaging marker, the pacing lead was placed for HBP at either the atrial (aHBP) or ventricular side (vHBP). RESULTS: During the implantation, the pacing lead placement was attempted for aHBP in two patients, vHBP in five patients, and first for aHBP then vHBP in one patient. The aHBP was selective and had a capture threshold of 1.6 ± 0.5 V@ 1.0ms and R-wave amplitude of 1.2 ± 0.4 mV. Ventricular-side His bundle capture was selective in four patients and nonselective in two patients. The vHBP capture threshold was 0.8 ± 0.4 V@ 1.0ms (P < .05 vs aHBP) and R-wave amplitude was 4.1 ± 1.5 mV (P < .05 vs aHBP). At the final pacing programming of 3.0 V@ 1.0ms, vHBP was nonselective in all six patients and aHBP remained selective in two patients. Pacing parameters remained stable at 3 months. CONCLUSION: The location of the TVA and tricuspid septal leaflet revealed by right ventriculography can be used as a landmark to identify the HBP site.