Left Atrial Function Assessed by Left Atrial Strain in Patients with Left Circumflex Branch Culprit Acute Myocardial Infarction.

Introduction Although left atrium ( LA) has played an important role in diastole, ischemic insult of atrium in acute myocardial infarction ( AMI) has not been clearly evaluated. Methods We hypothesized that LA function would be further decreased in AMI patients with a culprit lesion in the left circumflex branch ( LCX). This was an observational cohort study in a single university hospital. Echocardiography was performed to evaluate left ventricular diastolic function, LA volume, and LA function. Systolic ( LAS) and late diastolic ( LAA) LA strain were measured using speckle tracking echocardiography. Results Sixty-eight AMI patients treated with emergent or urgent percutaneous coronary intervention were enrolled. Global LAS strain was significantly lower in patients with a culprit lesion in the LCX than culprit lesions in other vessels (left anterior descending, 27.3 ± 6.8%; left circumflex, 20.1 ± 8.9%; right coronary artery, 23.3 ± 6.5%; P = 0.007). LA volume index did not differ significantly (P = 0.093). Other clinical and conventional echocardiographic parameters, including Doppler measurements, did not differ significantly. Conclusions Global LAS strain was lower in AMI patients with a culprit lesion in the LCX than those with culprit lesions in other vessels, without any significant difference in LA volume index. The lower global LAS strain might suggest decreased LA function resulting from ischemic insult by AMI with culprit lesions in the LCX. [ABSTRACT FROM AUTHOR]