Global peak left atrial longitudinal strain assessed by transthoracic echocardiography is a good predictor of left atrial appendage thrombus in patients in sinus rhythm with heart failure and very low ejection fraction - an observational study

Background: Peak left atrial longitudinal strain (PALS) can help identify left atrial appendage thrombus (LAAT) in patients with atrial fibrillation. Nevertheless, few studies have been performed in patients in sinus rhythm without established indications for anticoagulation but with increased risk of LAAT, such as heart failure (HF) with severe left ventricular systolic dysfunction patients. The primary aim of this study was to identify clinical and transthoracic echocardiography predictors of LAAT in HF patients with very low left ventricular ejection fraction and sinus rhythm. The secondary objective was to analyze frequencies and predictors of a composite clinical endpoint of death or hospitalization for ischemic stroke.

Methods: We included 63 patients with HF, left ventricular ejection fraction < 25%, sinus rhythm at presentation, no history of atrial fibrillation, and without any established indications for anticoagulation. We determined whether clinical and transthoracic echocardiography parameters, including left atrial strain analysis, predicted LAAT. Transesophageal echocardiography was performed in all patients. When LAAT was detected, anticoagulation was recommended. The participants were followed for a median of 28.6 months (range 4-40) to determine the composite endpoint.

Results: LAAT was found in 20 (31.7%) patients. Global PALS was the best independent predictor of LAAT in univariate and multivariate logistic regression analyses (Gini coefficient 0.65, area under the receiver-operating characteristic curve 0.83). A global PALS value below 8% was a good discriminator of LAAT presence (odds ratio 30.4, 95% CI 7.2-128, p < 0.001). During follow-up, 18 subjects (28.6%) reached the composite clinical endpoint. CHA₂DS₂-VASc score, use of angiotensin-converting-enzyme inhibitors or angiotensin receptor blockers, and body surface area were significant predictors for the composite endpoint of death or hospitalization for ischemic stroke in the multivariate regression model.

Conclusions: LAAT was relatively common in our group of HF patients and PALS has shown prognostic potential in LAAT identification. Further research is needed to determine whether initiation of anticoagulation or additional screening supported by PALS measurements will improve clinical outcomes in these patients.