Are wall thickness channels defined by computed tomography predictive of isthmuses of postinfarction ventricular tachycardia?

Heart Rhythm. 2019 Nov;16(11):1661-1668. doi: 10.1016/j.hrthm.2019.06.012. Epub 2019 Jun 15.


Background: Wall thickness (WT) in post-myocardial infarction scar is heterogenous, with channels of relatively preserved thickness bordered by thinner scar.

Objective: This study sought to determine whether 3-dimensionally-reconstructed computed tomography (CT) channels correlate with electrophysiological isthmuses during ventricular tachycardia (VT).

Methods: We retrospectively studied 9 postinfarction patients (aged 57 ± 15 years, 1 female) with 10 complete VT activation maps (cycle length 429 ± 77ms) created using high-resolution mapping. Three-dimensionally-reconstructed WT maps from CT were merged with the activation map during sinus rhythm (SR) and VT. The relationship between WT and electrophysiological characteristics was analyzed.

Results: A total of 41 CT channels were identified (median 4 per patient), of median (range) length 21.2 mm (17.3-36.8 mm), width 9.0 mm (6.7-16.5 mm), and area 1.49 cm2(1.00-1.75 cm2). WT in the channel was significantly thicker in the center than in the edge (median 2.4 mm vs 1.5 mm, P < .0001). Of 3163 (2493-5960) mapping points in SR, 382 (191-1115) local abnormal ventricular activities (LAVAs) were identified. One patient had a maximal proportion of LAVAs in 3-4 mm, 3 patients in 2-3 mm, 2 in 1-2 mm, and 2 in 0-1 mm. The VT isthmuses of all 10 VTs corresponded with 1-4 CT channels. Twenty-one of the 41 CT channels (51.2%) corresponded to a VT isthmus (entrance, mid, or exit). Electrophysiological VT isthmuses were more likely to be associated with CT channels that were longer (P = .04, odds ratio [OR] 1.05/mm), thinner (but not less than 1 mm) (P = .03, OR 0.36/mm), or parallel to the mitral annulus (P = .07, OR 3.93).

Conclusion: VT isthmuses were always found in CT channels (100% sensitivity), and half of CT channels hosted VT isthmuses (positive predictive value 51%). Longer and thinner (but >1 mm) CT channels were significantly associated with VT isthmuses.

Keywords: Contrast-enhanced multidetector computed tomography; High-resolution mapping; Isthmus; MUSIC; Myocardial infarction; Ventricular tachycardia; Wall thickness.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cicatrix / physiopathology
  • Contrast Media
  • Electrophysiologic Techniques, Cardiac
  • Female
  • Heart Conduction System / physiopathology
  • Humans
  • Imaging, Three-Dimensional
  • Male
  • Middle Aged
  • Myocardial Infarction / complications*
  • Retrospective Studies
  • Tachycardia, Ventricular / diagnostic imaging*
  • Tachycardia, Ventricular / etiology*
  • Tomography, X-Ray Computed / methods*


  • Contrast Media