The relationship between the left atrium/left ventricle ratio and atrial fibrillation in patients with ischemic stroke without significant left atrial enlargement.

Left atrial (LA) dilatation is a known predictor of atrial fibrillation (AF) in ischemic stroke patients. However, individuals with non-significant LA enlargement but an elevated LA/left ventricular end-diastolic diameter (LA/LVEDD) ratio may still be at risk for AF. This retrospective study included 404 patients hospitalized due to ischemic stroke and subsequently evaluated in the cardiology clinic. Patients with a left atrial diameter ≤ 45 mm were enrolled. AF was defined as an atrial rhythm lasting > 30 s. Patients were grouped based on the LA/LVEDD ratio: Group 1 (≥ 0.80) and Group 2 (< 0.80). AF was detected in 31 patients (7.6%). Eight out of 31 patients had an enlarged left atrium (LA diameter > 40 mm), and others had an LA diameter below 40 mm. Independent predictors of AF included older age, higher CHA₂DS₂-VA scores, larger LA diameter, elevated LA/LVEDD ratio, higher blood glucose, and elevated NT-proBNP. Compared to Group 2, Group 1 had significantly higher rates of hypertension (p = 0.004), diabetes mellitus (p = 0.024), and chronic kidney disease (p = 0.045). A statistically significant association was found between an LA/LVEDD ratio ≥ 0.80 and the presence of AF (p = 0.006). ROC curve analysis identified 0.82 as the optimal cut-off (sensitivity: 74%, specificity: 60%). The LA/LVEDD ratio, using a practical cut-off of 0.80, is a useful and memorable marker for identifying ischemic stroke patients at elevated risk for AF, even in the absence of marked LA enlargement.