ISSN: 2155-9880
Tahmeed Contractor, Gopi Krishna Panicker, Behzad Pavri and Yash Lokhandwala
Aims: Right ventricular pacing results in a prolongation of the left ventricular activation time, which is attributed to delayed activation of the left ventricular lateral wall. Left ventricular activation time has only been indirectly recorded in human subjects. The objective of this study was to model to directly measure left ventricular activation time utilizing a novel left lateral accessory pathway model and assess its shortening with His-bundle pacing, a proposed physiological pacing modality.
Materials and Methods: Consecutive adults with a pure retrograde conducting left lateral accessory pathway and both His-bundle as well as isolated myocardial capture were included. The interval from the pacing stimulus to the atrial activation in the left lateral region was measured as the left ventricular activation time, which was then compared during His-bundle versus myocardial pacing using paired t-test for means.
Results: A total of 50 subjects were found eligible for inclusion (Males=27; mean age=39±14). His-bundle pacing resulted in a significant reduction of left ventricular activation time when compared to myocardial pacing (122±15 vs 152±17; p<0.001).
Conclusion: Left ventricular activation time can be directly recorded in human subjects utilizing a pure-retrograde left lateral accessory pathway model and is significantly reduced with His-bundle pacing.