Vertebral Artery Stenoses Contribute to the Development of Diffuse Plaques in the Basilar Artery

Abstract

Vertebral artery (VA) stenosis is relevant to a high early risk of recurrent stroke and basilar artery (BA) is the most common intracranial site of atherosclerotic lesions. It is important to show predictive risk factors for transient ischemic attack (TIA) or posterior infarctions. The aim of the study is to investigate morphometry and hemodynamics in intracranial vertebral and basilar arteries of health and diseased patients to enhance the risk assessment. Based on the geometrical model reconstructed from CTA images in 343 patients, a transient three-dimensional computational model was used to determine the hemodynamics. Patients were classified in symmetric, asymmetric, hypoplastic, and stenotic groups while patients in the stenotic group were divided into unilateral, bilateral, bifurcation, and tandem stenotic sub-groups. Patients in bilateral, bifurcation, and tandem stenotic sub-groups had significantly lower basilar artery diameters than other groups. Patients in the stenotic group had significantly higher surface area ratio (SAR) of high time-averaged wall shear stress gradient (TAWSSG) and higher incidence of TIAs or posterior infarctions than other groups while patients in the tandem stenotic sub-group had the highest values (SAR-TAWSSG of 57 ± 22% and TIAs or posterior infarction incidence of 54%). The high SAR-TAWSSG is predisposed to induce TIAs or posterior infarction.

Probing the possibility of lesion formation/progression in vicinity of a primary atherosclerotic plaque: A fluid–solid interaction study and angiographic evidences

“…It should be noted that plaque formation is not only dependent on mechanical factors but also chemical factors, 44 blood composition and lipid content, 77 hematocrit and viscosity 78 . Each of the these parameters can be important, but according to the hemodynamic outcomes of the current study (as presented in Table 4), the most critical area is region VI where the probability of plaque formation and growth is almost twice of any other marked region (full susceptibility score) which is in favor of axial growth of the primary lesion The suggested axially extended configurations of the plaques is in complete agreement with previous patient‐specific observations 79 . Then, regions III in the PF and V in the PS obtained high‐vulnerability scores.…”

“…78 Each of the these parameters can be important, but according to the hemodynamic outcomes of the current study (as presented in Table 4), the most critical area is region VI where the probability of plaque formation and growth is almost twice of any other marked region (full susceptibility score) which is in favor of axial growth of the primary lesion The suggested axially extended configurations of the plaques is in complete agreement with previous patient-specific observations. 79 Then, regions III in the PF and V in the PS obtained high-vulnerability scores. Any degeneration in region V indicates more constricted lumen, for example, progression from S50 to S65.…”

Morphometric Study of the Intracranial Segment of the Vertebral Artery

“…Syncope is the clinical manifestation in the posterior cerebral artery occlusion or temporary sludge flow in the vertebral artery (VA). VA stenosis is the primary risk factor for recurrent stroke [ 1 ]. All the vertebral arteries had a tortuous course and were covered with rich venous plexuses [ 2 ].…”

Hemodynamic Differences Between Basilar Artery Fenestration and Normal Vertebrobasilar Artery: A Pilot Study

“…A recent study observed that patients with vertebral artery stenosis had significantly high SAR-TAWSSG and a high incidence of transient ischemic attacks (TIAs) or posterior circulation infarction. Further, high SAR-TAWSSG may induce TIA or posterior circulation infarction ( 25 ). In our study, we found that higher SAR-TAWSSG both at the bifurcation and basilar artery zone of patients with BAF compared to that of those patients with normal vertebrobasilar arteries.…”