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[摘要]：Obstructive apneas produce high negative intrathoracic pressure that imposes an afterload burden on the left ventricle. Such episodes might produce structural changes in the left ventricle over time. Doppler echocardiograms were obtained within 2 months of attended polysomnography. Patients were grouped according to apnea-hypopnea index (AHI): mild/no obstructive sleep apnea (OSA; AHI <15) and moderate/severe OSA (AHI >= 15). Mitral valve tenting height and area, left ventricular (LV) long and short axes, and LV end-diastolic volume were measured in addition to tissue Doppler parameters. Comparisons of measurements at baseline and follow-up between and within groups were obtained; correlations between absolute changes (Delta) in echocardiographic parameters were also performed. After a mean follow-up of 240 days mitral valve tenting height increased significantly (1.17 +/- 0.12 to 1.28 +/- 0.17 cm, p = 0.001) in moderate/severe OSA as did tenting area (2.30 +/- 0.41 to 2.66 +/- 0.60 cm(2), p = 0.0002); Delta tenting height correlated with Delta LV end-diastolic volume (rho 0.43, p = 0.01) and Delta tenting area (rho 0.35, p = 0.04). In patients with mild/no OSA there was no significant change in tenting height; there was a borderline significant increase in tenting area (2.20 +/- 0.44 to 2.31 +/- 0.43 cm(2), p = 0.05). Septal tissue Doppler early diastolic wave decreased (8.04 +/- 2.49 to 7.10 +/- 1.83 cm/s, p = 0.005) in subjects with moderate/severe OSA but not in in those with mild/no OSA. In conclusion, in patients with moderate/severe OSA, mitral valve tenting height and tenting area increase significantly over time. This appears to be related, at least in part, to changes in LV geometry. (C) 2012 Elsevier Inc. All rights reserved. (Am J Cardiol 2012;109: 1055-1059) |
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