Relationship between atherosclerosis and the sleep apnea syndrome: an intravascular ultrasound study.

Background: Sleep apnea hypopnea syndrome (SAHS) is a predictive factor of cardiovascular disease. We hypothesized that SAHS could influence coronary atherosclerosis plaque volume as assessed by 3-dimensional intravascular ultrasound (3D-IVUS).

Methods: Participating patients were identified from 2 studies assessing the progression of atherosclerosis in stable coronary artery disease using coronary 3D-IVUS.

Results: Nineteen patients, aged 61+/-8 years, with a body mass index of 29+/-5 kg/m(2) were studied. Increased apnea-hypopnea index (AHI) >or=15 was found in 12/19 patients (63%). Patients with AHI>or=15 had larger coronary atherosclerotic plaque volume than patients with AHI<15 (238+/-69 mm(3) vs 169+/-64 mm(3), p=0.047) and the difference was even larger in patients with obstructive apnea/hypopnea episodes compared to patients without (243+/-70 mm(3) vs 170+/-59 mm(3), p=0.03). There was a significant positive correlation between obstructive AHI and coronary atherosclerotic plaque volume (r=0.6, p=0.01). A significant positive correlation was also demonstrated between respiratory arousal index and coronary atherosclerotic plaque volume (r=0.6, p=0.02) and between total arousal index and coronary atherosclerotic plaque volume (r=0.5, p=0.03).

Conclusion: In patients with stable coronary artery disease, there was a significant relationship between the frequency of obstructive sleep apnea/hypopnea episodes and sleep fragmentation and the importance of coronary atherosclerotic plaque volume. 3D-IVUS is well suited to correlate coronary atherosclerosis and sleep breathing disorders at early stages.