MRI evaluation by T1 mapping of the post-myocardial infarction left ventricular thrombus

Abstract

Abstract Background Left ventricular thrombus is a post-myocardial infarct complication. It is composed of a fibrinous composition that evolves over time, being assessable by MRI. Objectives The objective of this study is to evaluate the post-myocardial infarction left ventricular thrombus on cardiac MRI by measuring its T1 mapping value, thus to determine the age of thrombus. Methods This observational retrospective study was performed on all patients scheduled for 3.0 Tesla cardiac MRI post-myocardial infarction on our institution from January 2015 to December 2022. Thirty-five patients with a left ventricular thrombus that may be measurable on T1 mapping sequence were included. They were separated in two groups based on the duration between the infarct and the MRI—less than three months: group A and more than three months: group B. T1 mapping value was measured for all thrombi. Results T1 of thrombi was 1098 ± 61 ms in group A and 1316 ± 75 ms in group B, p < 10–4. T1 of the myocardium was 1224 ± 73 ms in group A and 1254 ± 48 ms in group B, p = 0.139. T1 of the blood pool was 1934 ± 137 ms in group A and 2008 ± 124 ms in group B, p = 0.135. Conclusions Recent thrombi had shorter mapping T1 than old thrombi.