Desjardins B, Crawford T, Good E, Oral H, Chugh A, Pelosi F, Morady F, Bogun F. Infarct architecture and characteristics on delayed enhanced magnetic resonance imaging and electroanatomic mapping in patients with postinfarction ventricular arrhythmia.
Heart Rhythm 2009;
6:644-51. [PMID:
19389653 DOI:
10.1016/j.hrthm.2009.02.018]
[Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Accepted: 02/08/2009] [Indexed: 12/12/2022]
Abstract
BACKGROUND
Delayed enhanced magnetic resonance imaging (DE-MRI) can be used for the exact assessment of myocardial infarct scar. Electroanatomic (EA) mapping can identify the subendocardial extension of infarcts and is used to identify and eliminate areas critical for postinfarction ventricular arrhythmias.
OBJECTIVES
The purpose of this study was to correlate DE-MRI with EA mapping in postinfarction patients with ventricular arrhythmias to assess myocardial infarct architecture and its relationship to postinfarction ventricular arrhythmias.
METHODS
EA mapping during sinus rhythm was performed in 14 postinfarction patients (10 men; age 64 +/- 10 years; ejection fraction 0.33 +/- 0.12) referred for ablation of ventricular arrhythmias. All patients underwent prior DE-MRI. Both DE-MRI and EA mapping data were registered in three-dimensional space. Presence of scar and its transmurality as well as scar core versus gray zone were assessed on DE-MRI and correlated with EA maps; furthermore, the electrogram characteristics of the EA map were correlated with the DE-MRI.
RESULTS
Scar areas as assessed by bipolar and unipolar voltages in the EA map both correlated well with the scar as defined by DE-MRI. The best cutoff value to differentiate subendocardial scar from normal myocardium was 1.0 mV for bipolar voltage and 5.8 mV for unipolar voltage. Areas with DE had distinct electrophysiologic characteristics compared with nonenhancing sites. All identified sites that were critical for postinfarction ventricular tachycardia (31/31) and premature ventricular complexes (5/5) were located within areas of DE, with most (71%) being located in the core area of the scar.
CONCLUSIONS
DE-MRI can accurately predict the EA characteristics of corresponding subendocardial locations. Critical sites of postinfarction arrhythmias were confined to areas of DE. The scar information on MRI can be selectively imported into an EA mapping system to facilitate the mapping and ablation procedure.
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