Arteriopathic Effects of Hypertension by Signal Intensity Gradient from Time-of-Flight Magnetic Resonance Angiography

Hypertension is the most prevalent RF for cerebrovascular disease (CVD). Although previous studies have employed ultrasonography and phase-contrast magnetic resonance image (MRI) to assess cerebral hemodynamics, the quantitative impact of hypertension on cerebral arterial flow characteristics remains incompletely understood. This study focused on the relationship between hypertension, other risk factors (RF), and arterial velocity gradient using the signal intensity gradient (SIG) from time-of-flight magnetic resonance angiography (TOF-MRA).

This cross-sectional study included individuals who underwent health screening at our institution between January 2015 and June 2021. Participants with no history of CVD who underwent intracranial TOF-MRA were included. Arterial wall SIGs was measured in the cerebral arteries. Participants were categorized into four groups according to vascular RFs: none (no RF), other RFs (RFs except hypertension), hypertension-only, and hypertension-plus (hypertension with other RFs).

A total of 1154 healthy subjects (mean age 63.2 ± 9.5 years, 43.2% women) were enrolled. The hypertension-plus group had the highest systolic (125.3 ± 19.1 mm Hg) and diastolic (74.7 ± 10.5 mm Hg) blood pressures, HbA1c (6.1 ± 0.7%), intima-media thickness (0.86 ± 0.24 mm), and the highest rates of intracranial artery stenosis (14.4%) and chronic kidney disease (6.1%). The hypertension-plus group showed the lowest SIG values among all cerebral arteries. After adjusting for confounding factors, the hypertension-plus group showed significantly lower SIG values in the intracranial arteries but not in the extracranial arteries.

The arterial wall SIG was significantly associated with hypertension and other vascular RFs. SIG may offer quantitative information on the arteriopathic effects of hypertension, especially intracranial cerebral arteries.