Left ventricular subclinical dysfunction associated with myocardial deformation changes in obstructive sleep apnea patients estimated by real-time 3D speckle-tracking echocardiography

Previous studies have demonstrated that patients with obstructive sleep apnea (OSA) may develop left ventricular (LV) diastolic dysfunction. We aimed to study whether OSA patients have LV regional systolic dysfunction with myocardial deformation changes, despite a normal LV ejection fraction, using real-time 3D speckle-tracking echocardiography (Rt3D-STE). Seventy-eight patients with OSA and no comorbidities were studied. They were divided into the following three groups according to the apnea–hypopnea index (AHI): 5~15/h as group I (mild OSA, 26 cases), 15~30/h as group II (moderate OSA, 29 cases), and ≥30/h as group III (severe OSA, 23 cases). Thirty gender–age-matched normal subjects were included as controls. The parameters of LV diastolic function were acquired with traditional echocardiography. The LV myocardial deformation parameters were obtained, including the longitudinal (LS), circumferential (CS), radial (RS), and area (AS) strains, with Rt3D-STE. LV global systolic function was normal in all patients, but diastolic function was impaired in groups II and III (E/E′ was 9.6 ± 2.8 and 10.4 ± 2.5, respectively, p