Identifying cardiovascular risk factors that impact cerebrovascular reactivity: An ASL MRI study

Abstract

Background To maintain cerebral blood flow (CBF), cerebral blood vessels dilate and contract in response to blood supply through cerebrovascular reactivity (CR). Purpose Cardiovascular (CV) disease is associated with increased stroke risk, but which risk factors specifically impact CR is unknown. Study Type Prospective longitudinal. Subjects Fifty‐three subjects undergoing carotid endarterectomy or stenting. Field Strength/Sequence 3T, 3D pseudo‐continuous arterial spin labeling (PCASL) ASL, and T1 3D fast spoiled gradient echo (FSPGR). Assessment We evaluated group differences in CBF changes for multiple cardiovascular risk factors in patients undergoing carotid revascularization surgery. Statistical Tests PRE (baseline), POST (48‐hour postop), and 6MO (6 months postop) whole‐brain CBF measurements, as 129 CBF maps from 53 subjects were modeled as within‐subject analysis of variance (ANOVA). To identify CV risk factors associated with CBF change, the CBF change from PRE to POST, POST to 6MO, and PRE to 6MO were modeled as multiple linear regression with each CV risk factor as an independent variable. Statistical models were performed controlling for age on a voxel‐by‐voxel basis using SPM8. Significant clusters were reported if familywise error (FWE)‐corrected cluster‐level was P < 0.05, while the voxel‐level significance threshold was set for P < 0.001. Results The entire group showed significant (cluster‐level P < 0.001) CBF increase from PRE to POST, decrease from POST to 6MO, and no significant difference (all voxels with P > 0.001) from PRE to 6MO. Of multiple CV risk factors evaluated, only elevated systolic blood pressure (SBP, P = 0.001), chronic renal insufficiency (CRI, P = 0.026), and history of prior stroke (CVA, P < 0.001) predicted lower increases in CBF PRE to POST. Over POST to 6MO, obesity predicted lower (P > 0.001) and cholesterol greater CBF decrease (P > 0.001). Data Conclusion The CV risk factors of higher SBP, CRI, CVA, BMI, and cholesterol may indicate altered CR, and may warrant different stroke risk mitigation and special consideration for CBF change evaluation. Level of Evidence: 1 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2020;51:734–747.

Intracranial vascular feature changes in time of flight MR angiography in patients undergoing carotid revascularization surgery

“…However, unlike findings of the present study that TP3 perfusion is slightly larger than TP1 (see Table 2-3), these previous studies did not observe a significant difference between preoperative and long-term perfusion [18,20] except one study indicating a long-term increase of the ipsilateral ASL CBF in the MCA borderzone region [21]. This inconsistency may be due to multiple factors, such as the small sample size in most of these studies, unattended potential labeling failures in previous studies using ASL imaging [20], different study populations, and different time interval from surgery.…”

“…The finding that ASL CBF increased dramatically from TP1 to TP2, and then returned to a level similar to TP1 at TP3 (see Table 2-3) is largely in line with previous studies [18][19][20][21][22][23]. Most of these previous studies acquired perfusion data, either with ASL, DSC or SPECT, before CEA or CAS surgery and early post-operatively (less than 5 days), and showed that the early postoperative perfusion is much larger than preoperative perfusion.…”

“…Most of these previous studies acquired perfusion data, either with ASL, DSC or SPECT, before CEA or CAS surgery and early post-operatively (less than 5 days), and showed that the early postoperative perfusion is much larger than preoperative perfusion. Several studies also examined long-term (more than one month after surgery) perfusion measurements and reported findings similar to this study, that long-term perfusion is smaller than that acquired early post-operatively [18,20]. However, unlike findings of the present study that TP3 perfusion is slightly larger than TP1 (see Table 2-3), these previous studies did not observe a significant difference between preoperative and long-term perfusion [18,20] except one study indicating a long-term increase of the ipsilateral ASL CBF in the MCA borderzone region [21].…”

The value of 3D pseudo-continuousarterial spin labeling perfusion imaging in moyamoya disease—Comparison with dynamic susceptibility contrast perfusion imaging

“…ASL cerebral perfusion techniques are increasingly used in clinical practice because the advantages are that it does not require the injection of contrast agents, can be repeated, and can be completely quantified. The importance of ASL has been well validated in the study of ischemic brain diseases, and reduced CBF can cause irreversible damage to brain tissue, thereby increasing the risk of stroke (Noguchi et al, 2013;Soman et al, 2020).…”

Cerebral Vasoreactivity Changes Over Time in Patients With Different Clinical Manifestations of Cerebral Small Vessel Disease

“…For example, the studies on patients with cerebrovascular disease showed that the reduction in vasodilatory capacity in asymptomatic carotid disease can predispose for the development of cerebrovascular disease (Silvestrini et al, 2000). In 2020, Soman et al (2020) using arterial spin labeling MRI to evaluate which cardiovascular risk factors alter the CVR found that higher SBP, chronic kidney disease, history of past stroke, and hypercholesterolemia are responsible for the impaired CVR. Although the controls and patients with SVD in our study were well-balanced with the main comorbidities, we did not control other important risk factors of SVD.…”