1042 Assessment of left ventricular systolic function in obstructive sleep apnea with automatic function imaging and its relation relation with hypoxia

Abstract Funding Acknowledgements OSA & Subclinical myocardial impairment Background Early detection of left ventricular (LV) systolic dysfunction is crucial for patients with obstructive sleep apnea (OSA) . LV longitudinal strain (GLS), derived from automated function imaging (AFI) based on 2D echocardiography, provides a new tool to detect subclinical impairment of both global and regional myocardium. Its value in OSA remains unclear compared to traditional parameters since obesity is not uncommon in OSA, which may compromise the accuracy of AFI. We aimed to investigate the feasibility of AFI in OSA and further to explore the impact of OSA severity and degree of hypoxia on LV function. Methods Comprehensive transthoracic echocardiography was done in those receiving polysomnography (PSG) suspected as OSA consecutively (n = 322). All subjects were divided into 3 groups by apnea-hyponea index (AHI) by PSG (Control: AHI＜5; mild-to-moderate AHI 5-30; severe: AHI≥30) and GLS and mitral annular plane systolic excursion (MAPSE) were compared among the 3 groups. Results 322 patients with normal LVEF (≥50%) were finally analyzed. Though more segments were measured, inter- and intra- observer variability of GLS were comparable with MAPSE in a Bland-Altman analysis. For group comparison, GLS was reduced compared to the other 2 groups in the severe OSA category (p ≤ 0.001) while MAPSE showed no differences. Further analysis showed the feasibility of AFI was acceptable even in obese patients. In multivariable analysis of GLS, only maximum desaturation was an independent associated factor (p = 0.027). Conclusions Even in OSA patients with obesity, AFI-derived GLS is feasible. GLS is more sensitive than MAPSE or TDI for detection of reduced LV systolic function in OSA. Control(n = 27) Mild-Mod OSA(n = 145) Severe OSA(n = 160) P-value Age(years) 43 ± 13 47 ± 12 46 ± 11 0.218 Males, n(%) 17(63.0%) 118(81.4%) 154(96.3%) ＜0.001 BSA(m2) 1.82 ± 0.18 1.88 ± 0.18 1.97 ± 0.17*† ＜0.001 BMI(kg/ m2) 24.7 ± 4.4 26.8 ± 3.7* 28.6 ± 4.2*† ＜0.001 LVEF(%) 66.5 ± 6.4 67.0 ± 5.0 66.7 ± 4.6 0.813 Sep S’(cm/s) 8.3 ± 1.7 8.4 ± 1.5 8.7 ± 1.9 0.256 Sep E’(cm/s) 9.5 ± 3.0 9.0 ± 2.4 8.2 ± 2.0*† 0.003 E/ E’ 9.2 ± 2.9 9.1 ± 2.9 9.8 ± 2.9 0.145 GLS(%) 19.1 ± 2.7 19.0 ± 2.5 17.9 ± 2.4*† ＜0.001 MAPSE(mm) 15.1 ± 2.5 14.7 ± 2.3 14.3 ± 2.2 0.302 *p＜0.05 compared with mild OSA patients, †p＜0.05 compared with moderate OSA patients Echo Comparison between 3 OSA Groups