Epicardial–Endocardial Reentry in Ischemic Cardiomyopathy

Abstract

In ischemic cardiomyopathy, endocardial reentry has traditionally been the mechanistic paradigm for understanding ventricular tachycardia (VT). However, recognition is growing that epicardial myocardium is a critical component for VT substrate, even in patients with ischemic cardiomyopathy. In this report, we present a novel case of a three-dimensional VT reentry involving epicardial components and an endocardial exit.

Correlation of spatial patterns of endocardial pace mapping to underlying scar topography in patients with scar‐related ventricular tachycardia

“…However, in clinical practice, the critical isthmus is not necessarily on the subendocardial surface, even in ICM patients. 3,18 In the present study, approximately two-thirds of VT patients showed a CA-pattern, supportive of varied myocardial isthmus depths.…”

“…This is attributed to the proportion of orthodromic and antidromic capture, generating abrupt change with longer stim‐QRS interval in ICM patients. However, in clinical practice, the critical isthmus is not necessarily on the sub‐endocardial surface, even in ICM patients 3,18 . In the present study, approximately two‐thirds of VT patients showed a CA‐pattern, supportive of varied myocardial isthmus depths.…”

“…Patients with only AC-pattern showed significantly higher bipolar % scar area and lower scar ratios than those of CA-pattern (bipolar % scar: AC-pattern; 16 [9][10][11][12][13][14][15][16][17][18][19] vs. CA-pattern; 10 [7-13], p = .02, scar ratio: AC-pattern; 1.1 [0.9-1.3] vs. CA-pattern; 1.5 [1.3-1.9], p < .001) (Table 3). Proportion of CPs including LAVA and double potentials were equally distributed among groups (1.2% [0.7%-2.4%] vs. 0.8% [0.4%-1.9%], p = .33).…”