This Article Full Text Full Text (PDF) Data Supplement All Versions of this Article: 101/9/939    most recent CIRCRESAHA.107.158980v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ashikaga, H. Articles by Halperin, H. R. Search for Related Content PubMed PubMed Citation Articles by Ashikaga, H. Articles by Halperin, H. R. Related Collections Acute coronary syndromes Arrhythmias, clinical electrophysiology, drugs Chronic ischemic heart disease Ablation/ICD/surgery

(Circulation Research. 2007;101:939.)
© 2007 American Heart Association, Inc.

Integrative Physiology

Magnetic Resonance–Based Anatomical Analysis of Scar-Related Ventricular Tachycardia

Implications for Catheter Ablation

Hiroshi Ashikaga, Tetsuo Sasano, Jun Dong, M. Muz Zviman, Robert Evers, Bruce Hopenfeld, Valeria Castro, Robert H. Helm, Timm Dickfeld, Saman Nazarian, J. Kevin Donahue, Ronald D. Berger, Hugh Calkins, M. Roselle Abraham, Eduardo Marbán, Albert C. Lardo, Elliot R. McVeigh, Henry R. Halperin

From the Division of Cardiology (H.A., T.S., J.D., M.M.Z., R.E., V.C., R.H.H., S.N., R.D.B., H.C., M.R.A., E.M., A.C.L., H.R.H.), Johns Hopkins University School of Medicine, Baltimore, Md; Laboratory of Cardiac Energetics (H.A., B.H., E.R.M.), National Heart, Lung, and Blood Institute, NIH, Bethesda, Md; Division of Cardiology (T.D.), University of Maryland, Baltimore; and Heart and Vascular Research Center (J.K.D.), MetroHealth Hospital, Case Western Reserve University, Cleveland, Ohio.

Correspondence to Hiroshi Ashikaga, MD, PhD, Division of Cardiology, Johns Hopkins University School of Medicine, 720 Rutland Ave, Traylor 903, Baltimore, MD 20215. E-mail ha8000{at}gmail.com

In catheter ablation of scar-related monomorphic ventricular tachycardia (VT), substrate voltage mapping is used to electrically define the scar during sinus rhythm. However, the electrically defined scar may not accurately reflect the anatomical scar. Magnetic resonance–based visualization of the scar may elucidate the 3D anatomical correlation between the fine structural details of the scar and scar-related VT circuits. We registered VT activation sequence with the 3D scar anatomy derived from high-resolution contrast-enhanced MRI in a swine model of chronic myocardial infarction using epicardial sock electrodes (n=6, epicardial group), which have direct contact with the myocardium where the electrical signal is recorded. In a separate group of animals (n=5, endocardial group), we also assessed the incidence of endocardial reentry in this model using endocardial basket catheters. Ten to 12 weeks after myocardial infarction, sustained monomorphic VT was reproducibly induced in all animals (n=11). In the epicardial group, 21 VT morphologies were induced, of which 4 (19.0%) showed epicardial reentry. The reentry isthmus was characterized by a relatively small volume of viable myocardium bound by the scar tissue at the infarct border zone or over the infarct. In the endocardial group (n=5), 6 VT morphologies were induced, of which 4 (66.7%) showed endocardial reentry. In conclusion, MRI revealed a scar with spatially complex structures, particularly at the isthmus, with substrate for multiple VT morphologies after a single ischemic episode. Magnetic resonance–based visualization of scar morphology would potentially contribute to preprocedural planning for catheter ablation of scar-related, unmappable VT.

Key Words: ventricular tachycardia • catheter ablation • MRI

This article has been cited by other articles:

				T. Sasano, M. R. Abraham, K.-C. Chang, H. Ashikaga, K. J. Mills, D. P. Holt, J. Hilton, S. G. Nekolla, J. Dong, A. C. Lardo, et al. Abnormal sympathetic innervation of viable myocardium and the substrate of ventricular tachycardia after myocardial infarction. J. Am. Coll. Cardiol., June 10, 2008; 51(23): 2266 - 2275. [Abstract] [Full Text] [PDF]