A pre-clinical framework to characterize peri-infarct remodelling using in vivo T1 maps and CARTO data

Abstract

The purpose of this work was to use in vivo MR imaging and electro-anatomical maps to characterize dense scars and border zone, BZ (a mixture of collagen and viable fibers). To better understand how these measures might probe potentially arrhythmogenic substrates, we developed a preclinical swine model of chronic infarction and integrated in vivo MRI and electrophysiology (EP) data in five swine at 5-6 weeks post-infarction. Specifically, we first aligned and registered T1-maps (from MR studies) and bipolar voltage maps (from CARTO-EP studies) using Vurtigo, an open source software. We then performed a quantitative analysis based on circumferential segments defined in the short-axis of MR images. Our results demonstrated a negative linear relation between bipolar voltage maps and T 1 maps within the first two mm of the endocardial surface. The results of our novel approach suggest that T1-maps combined with limited EP measurements can be used to evaluate the biophysical properties of healing myocardium post-infarction, and to distinguish between the infarct categories (i.e., dense scar vs. BZ) with remodelled electrical characteristics. © 2013 Springer-Verlag.