Abstract 2420: Impaired Waveform Index of Ophthalmic Artery Predicts the Severity of Systemic Atherosclerosis
Background Doppler imaging studies of ophthalmic artery (OA), which is the first major branch of internal carotid artery and is representative of microarterioles, have been recently performed. The ratio of systolic to diastolic mean velocity (Sm/Dm) is considered as an index of the severity of ophthalmic arteriosclerosis and its increase indicates the impaired OA microcirculation. The progression of systemic atherosclerosis suggests the decrease of arterial compliance which can be estimated by stroke volume divided by pulse pressure. We assessed the hypothesis that the waveform index of OA would be associated with severity of systemic atherosclerosis.
Methods and Results We enrolled 180 patients who underwent cardiac catheterization. Doppler studies of OA were examined in 90 patients with coronary artery disease (CAD) and 90 control patients who had been matched for age and sex with CAD. The Sm/Dm of OA in patients with CAD was significantly higher than that in control patients (2.52±0.43 vs 2.13±0.32, p<0.0001). The Sm/Dm was higher in proportion to the increase in number of the coronary artery stenosis (0-vessel disease: 2.13±0.32, 1-vessel disease: 2.32±0.31, multi-vessel disease: 2.62±0.45). The Sm/Dm positively correlated with age (r=0.39, p<0.0001), pulse pressure (r=0.39, p<0.0001), C-reactive protein (r=0.21, p<0.005), fibrinogen (r=0.21, p<0.005), maximum carotid intima-media thickness (r=0.37, p<0.0001), pulse wave velocity (r=0.24, p<0.005), diabetes mellitus (r=0.24, p<0.005), CAD (r=0.45, p<0.0001) and negatively correlated with diastolic blood pressure (r=−0.27, p<0.0005) and arterial compliance (r=−0.39, p<0.0001). The Sm/Dm was an independent determinant of arterial compliance in a multiple regression analysis (Table⇓).
Conclusions The waveform index of OA is closely associated with risk factors for atherosclerosis and may help to explain missing link between peripheral microcirculation and systemic arterial compliance.