Rupa Bala, M.D.: Research grant from Biosense Webster, St. Jude Medical, Medtronic; Speakers honoraria from Biosense Webster.
New Endpoint for Ablation of Ventricular Tachycardia: Change in QRS Morphology with Pacing at Protected Isthmus as Index of Isthmus Block
Article first published online: 2 SEP 2009
© 2009 Wiley Periodicals, Inc.
Journal of Cardiovascular Electrophysiology
Volume 21, Issue 3, pages 320–324, March 2010
How to Cite
BALA, R., DHRUVAKUMAR, S., LATIF, S. A. and MARCHLINSKI, F. E. (2010), New Endpoint for Ablation of Ventricular Tachycardia: Change in QRS Morphology with Pacing at Protected Isthmus as Index of Isthmus Block. Journal of Cardiovascular Electrophysiology, 21: 320–324. doi: 10.1111/j.1540-8167.2009.01596.x
Francis E. Marchlinski, M.D.: Biosense Webster: Sponsored research/advisory panel/lecture honorarium; Boston Scientific/Guidant: Sponsored research/lecture honorarium; GE Healthcare: Advisory panel; Medtronic: Sponsored research/lecture honorarium; St. Jude Medical: Sponsored research/lecture honorarium.
Sandhya Dhruvakumar, M.D. and Shuaib A. Latif, M.D.: No conflicts of interest or disclosures declared.
- Issue published online: 22 FEB 2010
- Article first published online: 2 SEP 2009
- Manuscript received 3 July 2008; Revised manuscript received 25 June 2009; Accepted for publication 22 July 2009.
- Tetralogy of Fallot;
- ventricular tachycardia;
- VT ablation;
- electroanatomical mapping
New Endpoint for Ablation of Ventricular Tachycardia. Introduction: Endpoints confirming block in the critical isthmus in sinus rhythm and with pace mapping have not been established.
Methods and Results: A 44-year-old man with a history of Tetralogy of Fallot presented with recurrent ventricular tachycardia (VT). Entrainment mapping was consistent with a macroreentrant circuit rotating in a clockwise fashion under the pulmonic valve. After termination of the VT in a critical isthmus located on the conal free wall, a pace map proximal to the site of successful ablation was consistent with a change in QRS morphology. This change in QRS morphology suggested critical isthmus block and successful ablation, which was confirmed by noninducibility with programmed stimulation.
Conclusion: Evidence of conduction block can be used as an additional endpoint for successful ablation of VT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 320–324, March 2010)