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Updated: Nov 9, 2025

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine
Published on: February 17, 2018
Postpacing interval is shorter than tachycardia cycle length-What's the mechanism?
Anand Manickavasagam1, Krishnakumar Nair2, Sirish Chandra Srinath Patloori1
1Department of Cardiology Christian Medical College Vellore India.
Abstract:
A 33-year-old male who underwent surgery for Tetralogy of Fallot presented with atrial flutter. Electrophysiology study revealed concealed entrainment along the mid lateral right atrium with postpacing interval shorter than the tachycardia cycle length. Ablation at this site terminated the tachycardia. The presence of shorter PPI than TCL was due to a large virtual electrode leading to downstream capture of far field tissue. This case demonstrates that sites showing PPI shorter than TCL are in a slow conducting narrow critical isthmus and hence constitute good ablation targets.
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