Left Ventricular Wall Thickness and Decrement Evoked Potentials in Ablation of Ischemic Ventricular Tachycardia.

INTRODUCTION

Preprocedural imaging can improve the success rate of ventricular tachycardia (VT) ablation. Left ventricular wall thickness (LVWT) measured by cardiac computed tomography (CT) can be used to identify infarct regions. We sought to determine whether an association exists between left ventricular wall thickness (LVWT) as obtained from CT imaging and the presence of decrement evoked potentials (DeEPs) as obtained from electroanatomic mapping.

METHODS

In this single-center, retrospective analysis, 14 patients with ischemic heart disease who underwent a VT ablation in the University Medical Center Groningen (UMCG) between January 2021 and March 2023 were included. CT images as well as electroanatomic maps were obtained and processed, after which a 3D model of the left ventricle was obtained and segmented in 17 segments. The primary outcome was the presence of DeEPs, defined as late potentials exhibiting a decremental delay response longer than 20 ms after S2 extrastimulus delivery (with the extrastimulus delivered at 50 ms above the ventricular effective refractory period [VERP]), in each of the left ventricular segments. The mean segment LVWT and coefficient of variation of LVWT, defined as the standard deviation of the LVWT of each segment divided by the mean segment LVWT, were analyzed as determinants of the primary outcome.

RESULTS

The mean age was 69 ± seven years and 13 (92.9%) patients were male. The mean LVWT was significantly associated with the presence of DeEPs in left ventricular segments [odds ratio (OR) 0.65 (95% confidence interval (CI) 0.55 - 0.78); p < 0.001], as was the coefficient of variation of LVWT [OR 1.10 (95% CI 1.06 - 1.15); p < 0.001].

CONCLUSIONS

The mean and coefficient of variation of LVWT were significantly associated with the presence of DeEPs. This may possibly allow for the preprocedural identification of arrhythmogenic regions as potential targets for VT ablation.