Prediction of left ventricular thrombus after STEMI based on readily available clinical, echocardiographic and ECG variables

Abstract

Abstract Background Left ventricular thrombus (LVTh) is an uncommon yet serious complication after ST-segment elevation myocardial infarction (STEMI). LVTh can be accurately detected in late gadolinium enhancement (LGE) sequences in cardiac magnetic resonance (CMR). However, selection of patients who should undergo this imaging technique for LVTh detection is not defined yet. Purpose We aim to stratify the risk of LVTh occurrence after STEMI by clinical, echocardiographic and ECG variables during admission and help select patients who should undergo CMR for LVTh detection. Methods Our registry comprised reperfused STEMI patients who underwent early (1-week) and late (6-month) CMR for clinical indication. LGE sequences were used to analyze the presence of LVTh. Baseline clinical characteristics were recorded. Echocardiography (Echo) was performed before discharge and left ventricular (LV) ejection fraction (LVEF, in %), LV end-diastolic and end-systolic diameters (in mm), tricuspid annular plane systolic excursion (TAPSE, in mm), E and A waves velocities (in m/s) and left auricular antero-posterior diameter (in mm) were measured. ECG during admission were analyzed and maximum and minimum ST-segment elevation, resolution of ST-segment (in %) and the number of leads with Q wave and ST-segment elevation >1mm (Q-STE) were recorded. Univariate and multivariate comparisons were performed to check for an association with LVTh in the first 6 months after STEMI (by CMR). A p<0.05 was considered statistically significant. Results The final cohort comprised 377 STEMI patients (mean age 58.51±11.64 years, 82% male). LVTh was detected in 29 (7.7%) patients by CMR during the first 6 months after STEMI. Predictors of LVTh on multivariate analysis were anterior infarction (HR 4.57 [1.28-16.29], p=0.02), Echo-LVEF (HR 0.97 [0.93-0.99] per %, p=0.04) and Q-STE (HR 1.33 [1.06-1.67] per lead, p=0.01). Echo-LVEF (best cut-off: ≤48%) and Q-STE (best cut-off: >3 leads) were dichotomized and several risk categories for LVTh were defined. In patients with zero or one risk factor the prevalence of LVTh ranged from 1.6% to 5.2% (if anterior infarction and no other risk factors). Patients with anterior infarction and any other risk factor had a 14.3% prevalence of LVTh. However, the highest prevalence was found in patients with concomitantly anterior infarction, Echo-LVEF ≤48% and Q-STE in >3 leads - in this subgroup (n=34, 9% of the cohort) LVTh was found in 26.5% of patients. Conclusions Left ventricular thrombus occurrence in the first 6 months after STEMI can be predicted by readily available clinical (anterior infarction), echocardiographic (LVEF) and ECG (Q-STE) variables before discharge. More than a quarter of patients with anterior infarction, Echo-LVEF≤48% and Q-STE in >3 leads depict LVTh. This could help select patients who should undergo CMR after infarction for LVTh detection.Central Figure.