Outer Loop Tachycardia. Introduction: Ventricular tachycardia (VT) alter postinfarct ventricular septal defect (VSD) repair has not been well characterized.
Methods and Results: A 55-year-old man developed refractory VT after inferior wall infarction and VSD repair. Entrainment demonstrated a broad reentry circuit path (outer loop) between the tricuspid annulus and VSD patch. A series of radiofrequency (RF) lesions transected this path, abolishing VI’ and producing conduction block between the inferior and superior aspects of the basal right ventricular septum.
Conclusion: Some VTs have broad reentry loops requiring ablation by a series of RF lesions across the path to create a line of block. This approach is analogous to that for atrial flutter.