Catheter Ablation -> Ventricular Arrhythmias -> Mapping & Imaging D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-104 - Prediction Of Location Of Late Potentials For Ventricular Tachycardia Ablation With Tc-99m Scintigram Scar (ID 1366)

 K. Ozu: Nothing relevant to disclose.


Background: Late potential (LP) in low voltage area is the important targeted substrate of the radiofrequency ablation for ventricular tachycardia (VT). Efficacy of MRI or CT for prediction of the VT substrate has been reported. On the other hands, Tc-99m scintigram has been reported to determine the viability of ventricular myocardium and discriminate the low viability area.
Objective: In this study, we evaluated that we could predict the location of LPs with Tc-99m scintigram.
Methods: In 8 patients (age, 67.5±8.6 years ; 8 male ; left ventricular (LV) ejection fraction, 26.0±8.7%) with ischemic cardiomyopathy and VT, electroanatomical map (EAM) and Tc-99m scintigrafic image of LV were obtained and were divided into twenty segments. LPs were determined as isolated potentials after QRS and were evaluated in EAM. The relation between LPs and scintigrafic characteristics were evaluated in total of 160 segments (Figure A).
Results: LPs were recorded in 59 segments. According to the Tc-99m uptake rate, cut off value 35% was set for the prediction of the location of LPs with ROC curve (FigureB). LPs were observed in the lower scintigram perfusion segments with ≤35% uptake rate (n=61) more than the segments with >35% uptake rate (n=99) with statistical significance (78.6% vs 11.1% p<0.0001). Moreover, enhanced cardiac CT was performed in 4 patients before ablation. The merged 3D images with CT and Tc-99m Scintigram were available. Figure C showed the well coexistence between LP recorded area and low viability area with ≤35% uptake area.
Conclusion: Lower perfusion area of Tc-99m scintigram could be utilized to predict VT substrate location in ICM patients and make the mapping procedure more simple.