Arterial blood flow to the brain in patients with vascular disease: the SMART Study

To retrospectively investigate which characteristics are related to total arterial blood flow to the brain in patients with symptomatic vascular disease.

The study was approved by the ethics committee of the authors' institution, and written informed consent was obtained. The total volume flow rate (tVFR) values in the internal carotid arteries and the basilar artery in 636 patients (536 men, 100 women; mean age, 58 years) with symptomatic vascular disease were measured with two-dimensional phase-contrast magnetic resonance (MR) angiography. Reference tVFR values in the general population were obtained from previous research involving 158 subjects (73 men, 85 women; mean age, 60 years).

A higher tVFR was found in patients with symptomatic vascular disease, but this association was statistically significant in only those patients in the 7th decade of life. The mean tVFR decreased with increasing age (-3.4 mL/min per year; 95% confidence interval [CI]: -4.3, -2.5). Diabetes (-27.6 mL/min; 95% CI: -52.6, -2.6) and increasing body mass index (BMI) (-2.8 mL/min per BMI unit; 95% CI: -5.3, -0.2) were associated with lower tVFR. Patients with vascular disease in a cerebral location had lower tVFR values (-39.7 mL/min; 95% CI: -65.1, -14.3) than did patients with symptomatic vascular disease elsewhere in the vascular tree.

Patients with symptomatic vascular disease had slightly higher arterial blood flow to the brain compared with the general population. The tVFR decreased with increasing age and increasing BMI, and patients with diabetes had lower tVFR values than did those without diabetes. Patients with vascular disease in a cerebral location had lower tVFR values than did those with symptomatic vascular disease at other arterial sites.