case_images: PMC3250344_01
case_images: (A and B) Cardiac CT images of left ventricle (LV) during systole and diastole. (C and D) 3D reconstructed CT images show LV cavity obstruction during systole because of significant mid-septal hypertrophy. (E) 12-lead ECG during ventricular tachycardia (VT) on admission, suggesting LV apical posterior wall origin of VT. CT, computed tomography.
case_images: ymj-53-221-g001.jpg
case_images: PMC3250344_01_ymj-53-221-g001.jpg
case_images: F1
case_images: Five months earlier, he underwent ICD implantation due to sustained monomorphic VT associated with HCM (Fig. 1A-D) and had been taking amiodarone. 12-lead ECG localized the focus of VT on left ventricular (LV) apical posterior wall (Fig. 1E).
case_images: (A and B) Left ventriculograms of LAO 35  (B) and RAO 35  views. Due to severe mid-septal hypertrophy, the LV had an hourglass-like morphology showing apical ballooning. (C and D) Catheter positions of ablation site (marked with asterisk) in LAO 35  (C) and RAO 35  views (D) match to the margin of apical ballooning due to significant mid-septal hypertrophy. (E) Electroanatomical activation map revealed that the earliest activation site of VT was located at the apical posteroseptum of the LV at the border of apical ballooning. LAO, left anterior oblique view; RAO, right anterior oblique view; VT, ventricular tachycardia.
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case_images: F2
case_images: ICD discharges despite intravenous amiodarone and beta-blocker, we decided radiofrequency catheter ablation (RFCA). In electrophysiology laboratory, left ventriculography revealed an hourglass shaped LV with apical ballooning (Fig. 2A and B). Thermo-Cool, Biosense Webster, Diamond Bar, CA, USA) after 3D-electroanatomic mapping (CARTO XP, Biosense Webster, Diamond Bar, CA, USA) (Fig. 2C, D and E). The earliest activation site of
case_images: During VT, the target ablation site (ABLd) preceded the QRS onset by 50 ms (vertical line). showing double potential. VT was terminated by mechanical bump or RF energy delivery. VT, ventricular tachycardia.
case_images: ymj-53-221-g003.jpg
case_images: PMC3250344_01_ymj-53-221-g003.jpg
case_images: F3
case_images: USA, 30 to 50 W, 30 mL/min) at the site showing double potential (Fig. 3) and the earliest activation on CARTO image (Fig. 2E). VT could not be inducible by ventricular stimulation test after RFCA. Unfortunately, however, the identical VT recurred within 1 hour after procedure.