Left atrial mechanics for secondary prevention from embolic stroke of undetermined source

Aims Anticoagulation is not justified unless atrial fibrillation (AF) is detected in cryptogenic stroke (CS) patients. We sought to explore whether left atrial (LA) remodelling is associated with embolic stroke of undetermined source (ESUS). Methods and results In this prospective study, we evaluated consecutively 186 patients in sinus rhythm who presented with an acute ischaemic stroke (embolic and non-embolic) and sex- and age-matched controls. We performed continuous electrocardiogram (ECG) monitoring to capture paroxysmal AF episodes as recommended by the guidelines. After 12 months of follow-up, continuous ECG monitoring was repeated in patients with undetected AF episodes. We quantified LA reservoir and contraction strain (LASr and LASct) by speckle-tracking, LA volumes by 3D echocardiography. Out of 186 patients, 149 were enrolled after comprehensive investigation for the source of ischaemic stroke and divided into other cause (OC) (n = 52) and CS (n = 97) groups. CS patients were also subdivided into AF (n = 39) and ESUS (n = 58) groups. Among CS patients, LA strain predicted AF independently from CHARGE-AF score and LA volume indices. ESUS group, despite no captured AF, had significantly worse LA metrics than OC and control groups. AF group had the worst LA metrics. Moreover, LASr predicted both CS (embolic stroke with and without AF) and ESUS (embolic stroke with no detected AF) independently from LAVImax and CHA2DS2-VASc score. LASr >26% yielded 86% sensitivity, 92% specificity, 92% positive, and 86% negative predictive values for the identification of ESUS (areas under curve: 0.915, P < 0.0001, 95% confidence interval: 0.86–0.97). Conclusion Echocardiographic quantification of LA remodelling has great potential for secondary prevention from ESUS.

Can left atrial mechanics predict anticoagulation in cryptogenic stroke?

Introduction Ischemic stroke is a leading cause of death and disability in the Western world, frequently due to cardioembolism and atherothromboembolism. Cryptogenic strokes occur without a well-defined aetiology after a standard vascular and cardiac evaluation, and secondary prevention may include antiplatelet therapy while awaiting results of long-term cardiac monitoring. In this study, we aimed to identify echocardiographic predictors of paroxysmal atrial fibrillation (AF) latter identified in follow-up of patients with cryptogenic stroke. Methods We retrospectively assessed all patients with cryptogenic stroke admitted in our hospital in the last 2 years. Only patients in normal sinus rhythm with a minimum of 24 hours of cardiac monitoring at admission and 24 hours Holter monitor within 6 months after discharge were included. Echocardiographic measures included left ventricle ejection fraction, left atrium (LA) volume, left and right atrium longitudinal strain, left and right ventricle longitudinal strain, E/A ratio, E/e' ratio, isovolumetric relaxation time (IVRT) and E wave deacceleration time. Echocardiographic data was assessed to determine its accuracy to identify AF. Results The study included 32 patients with a mean age of 72±10 years and a male preponderance (87.5%). AF was identified in 12 (37.5%) patients. This group of patients had a larger indexed LA volume (44.3 vs 29.1 mL/m2, p=0.043), a lower IVRT (87 vs 116 ms, p=0.028), and a lower LA longitudinal strain in contractile (6.7 vs 13.6%, p<0.001) and in reservoir phase (17.1 vs 23.6%, p=0.042). All other variables were not significantly different among groups, including LA longitudinal strain in conduit phase. LA longitudinal strain in contractile phase showed the best predictive power with an area under the ROC curve of 0.925 (95% CI 0.82–1 p=0.001). The cut-off value that best predicted AF was 8.17% with a sensitivity of 1 and specificity of 0.9. Conclusion LA longitudinal strain in contractile phase is a powerful method to identify AF in cryptogenic stroke. When reduced, anticoagulation may be considered in order to prevent recurrence. Further studies are warranted to reproduce these results in larger cohorts. Funding Acknowledgement Type of funding source: None