Anti-tachycardia pacing efficacy regarding VT rates and ATP failures. (A) Efficacy of ATP proximal and distal delivery and the total for fast and slow VTs. (B) Anti-tachycardia pacing efficacy of all locations is similar to that shown in Figure 5. (C) Mechanisms for failed ATP cases in fast and slow VTs. Location nomenclature as in Figure 5. * P < 0.05, ***P < 0.0001. VT, ventricular tachycardia.