Isolated septal substrate for ventricular tachycardia in nonischemic dilated cardiomyopathy: Incidence, characterization, and implications

摘要: Background The substrate for ventricular tachycardia (VT) in nonischemic cardiomyopathy (NICM) has a predilection the basolateral left ventricle with right bundle branch block VT morphology. Objective purpose of this study was to describe unique group NICM patients septal substrate. Methods Between 1999 and 2010, 31 (11.6%) 266 undergoing ablation had no lateral involvement. Mean age 59 ± 12 years, ejection fraction 30% 14%. Eight heart block. Results Cardiac magnetic resonance showed delayed enhancement 8 9 patients. Electroanatomic mapping demonstrated bipolar low voltage ( 2 precordial transition pattern break 17% suggesting periseptal exit. After targeted ablation, inducible 66% "clinical targeted" 86%. Over mean follow-up 20 28 months, recurred 10 (32%) Conclusion Isolated is uncommon NICM. Biventricular low-voltage zones extending from basal septum are characteristic, but scarring can be entirely intramural as evidenced by unipolar/bipolar electrograms imaging. Multiple unmappable morphologies rule, often requiring several procedures aggressively targeting achieve moderate long-term control.