Incremental Value of Left Atrial Function Analysis in the Assessment of Left Ventricular Filling Pressures in Patients with ST-Elevation Myocardial Infarction.

Background: Left atrial (LA) reservoir strain provides interesting information about left ventricular (LV) filling pressure. However, the advantages of atrial reservoir strain in comparison with conventional parameters in patients with myocardial infarction are not clear yet.

Methods: Fifty patients with ST-elevation myocardial infarction (STEMI) prospectively underwent echocardiographic assessment of LV systolic and diastolic function by conventional parameters and two-dimensional speckle tracking longitudinal strain of left atrium. LV filling pressure was estimated by brain natriuretic peptide (BNP) levels.

Results: Systolic and conventional diastolic parameters did not show significant differences between patients with increased and normal BNP values, whereas LA reservoir strain was reduced (33.1 ± 8% vs. 46.5 ± 9.8%; P = 0.001) in patients with higher BNP levels. LA reservoir strain had higher area under curve value (0.880) than the other parameters in identifying patients with elevated BNP and a cut-off value of 40.5% reached sensitivity and specificity values of 93% and 86% and positive and negative predictive values of 92% and 85%. LA reservoir strain reclassified 23 patients with increased BNP values, which were previously estimated to have normal (16 patients) and undeterminable LA pressure (seven patients) by using the recommended algorithm for diastolic function.

Conclusions: LA reservoir strain is a useful tool for the evaluation of diastolic function and seems to be more sensitive than conventional parameters in the detection of subtle increase of LV filling pressure in patients with STEMI. It allows physicians to reclassify patients with undeterminable diastolic function according to conventional algorithm.