Evaluation of subclinical left ventricular systolic dysfunction in patients with obstructive sleep apnea by automated function imaging method; an observational study

Objective: We aimed to evaluate the subclinical left ventricular (LV) systolic dysfunction with the automated function imaging method (AFI) based on speckle tracking echocardiography (STE) in obstructive sleep apnea patients (USA) with normal left ventricular ejection fraction (LVEF) and without any confounding disease that can cause myocardial dysfunction. Methods: Twenty-one healthy individuals and 58 USA patients were included in this observational cross-sectional study. According to the severity of disease, USA patients were examined in three groups; mild, moderate and severe USA. Apical 2-, 3- and 4- chamber images were obtained for AFI evaluation. The global systolic longitudinal strain (GL(S)) values were determined for each view, and averages of these were used in comparison of the patient groups. One-way ANOVA, Kruskal-Wallis, Pearson correlation tests and linear regression analysis were used for statistical analysis. 3 Results: The GL(S) values of the USA patients were lower than of the healthy individuals and these values were decreased along with the USA severity (Healthy:-25.58 +/--2.16%, Mild:-23.93 +/--3.96%, Moderate:-21.27 +/--2.60%, Severe:-16.94-2.66%, respectively). The difference was significant between moderate USA patients and healthy individuals, and significant between severe USA patients and all other groups (p<0.03). The apnea-hypopnea index was found to be correlated with the GL(S) (beta=-0.659, 95% CI: 0.09-0.17, p<0.001). Conclusion: Longitudinal LV mechanics in USA patients with normal LVEF are deteriorated in the subclinical stage being associated with the severity of disease. AFI can be used as an effective and safe method in the determination of subclinical myocardial dysfunction in USA patients, because it is semi-automated and easy to use with a short analysis time. (Anadolu Kardiyol Berg 2012; 12:320-30)