We studied a cohort of in-hospital ischemic stroke patients referred for transthoracic echocardiography. Treating neurologists determined stroke etiology based on the TOAST classification. Left atrial contractile function was assessed using 2-dimensional echocardiography to determine their ejection fraction and speckle tracking to measure left atrial strain rate: a-wave. Left atrial function was compared between stroke etiology subgroups and healthy controls.
Ninety-seven patients (aged 67 ± 15 years) with ischemic stroke (16.5% large-artery atherosclerosis, 15.5% small-vessel occlusion, 11.3% cardioembolic, 5.1% other determined etiology, 51.1% undetermined etiology) and 10 healthy volunteers (aged 63 ± 7 years) were included. Left atrial ejection fraction was significantly decreased only in patients with stroke of cardioembolic and undetermined etiology compared with the control group (31.5 ± 17.2%, 40.2 ± 17.1%, and 59.1 ± 8.4%, respectively; P = .004). The left atrial strain rate was significantly lower in patients with stroke caused by cardioembolic or undetermined etiology, or large-artery atherosclerosis compared with controls (−0.86 ± 0.49, −1.31 ± 0.56, −1.5 ± 0.47, −2.37 ± 1.18, respectively; P < .001).
Patients with stroke of undetermined etiology with left atrial function (ejection fraction and strain) similar to that of cardioembolic stroke patients may be misclassified and could potentially benefit from prolonged electrocardiography monitoring. Left atrial function analysis (ejection fraction and strain) might help to identify potential cardioembolic sources in patients with stroke of undetermined etiology.