Apical mechanical dysfunction independently predicts left ventricular thrombus formation after anterior myocardial infarction
J Jones, B Coldea, K Rathod, G Lloyd, A Mathur, D JonesAbstract
Background
Left ventricular (LV) thrombus remains a clinically important complication following anterior acute myocardial infarction (AMI), associated with embolic risk and exposure to prolonged anticoagulation. Current risk stratification relies predominantly on left ventricular ejection fraction (EF), yet EF lacks specificity: many patients with reduced EF do not develop thrombus, while others with relatively preserved EF do. Given the bleeding risks associated with anticoagulation alongside potent dual anti-platelets, identification of patients truly at risk is required. Apical rotation (twist), reflecting the heart’s systolic wringing motion, may provide a mechanistic marker of regional stasis predisposing to thrombus formation.
Purpose
To determine whether apical rotation (twist) assessed by speckle tracking echocardiography predicts LV thrombus formation following AMI.
Methods
In a prospective registry of 200 patients with anterior AMI, apical twist (degrees) was quantified using speckle tracking echocardiography. Baseline imaging was performed prior to hospital discharge. Follow-up imaging (CMR or TTE) was conducted at a median of 1.5 months to assess for thrombus presence. Patients were categorised into two groups: those who developed LV thrombus (34.5%) and those without thrombus (65.5%).
Results
The baseline characteristics and echocardiographic parameters were comparable between groups. Peak apical twist was significantly lower in patients who developed thrombus [6.0° (IQR 3.4-8.1°)] compared to those who did not [10.5° (IQR 7.1-14.3°)], p<0.001. Representing a marked blunting of apical rotation throughout systole. Univariate analysis confirmed an association between decreased apical twist and thrombus formation [OR 1.28, 95% Cl 1.17-1.39, p<0.001]. After adjusting for EF, global longitudinal strain and LV end diastolic volume, apical twist remained an independent predictor of LV thrombus [OR 1.22, 95% Cl 1.11-1.34, p<0.001]. ROC analysis identified an optimal twist cut-off of 8.6° for predicting thrombus development, with an AUC of 0.79.
Conclusion
In patients with anterior AMI, apical twist is an independent predictor of LV thrombus and provides better discrimination than conventional systolic indices. Integrating apical mechanical assessment into clinical workflows offers a targeted based approach to post-AMI surveillance and anticoagulation strategies. Large-scale validation is required to establish apical twist as a practical tool for LV thrombus risk stratification.Figure:Apical twist and LV thrombus