An Improvement of Cerebral Hemodynamics following Percutaneous Transluminal Angioplasty in Patients with Atherosclerotic Arterial Stenosis

Abstract

The purpose of this study was to evaluate changes in cerebral hemodynamics following percutaneous transluminal angioplasty (PTA) in patients with atherosclerotic cerebral arterial stenosis. PTA was performed on the patients under the condition that the arterial stenosis ratio was 70% or more and regional cerebrovascular reserve (rCVR) had decreased to 10% or less. Resting regional cerebral blood flow (rCBF) and rCVR responding to acetazolamide loading were measured by (133)Xe single photon emission tomography (SPECT) just prior to and 1 month after PTA. The average stenosis ratio was significantly improved from 77% to 36% one month after PTA. There were 185 preoperative normal rCBF and normal rCVR regions, 176 region (95%) of which retained their normal rCBF and normal rCVR postoperatively. In 9 regions (5%) only rCVR worsened. Preoperatively, there were 59 normal rCBF and decreased rCVR regions. Forty-five (76%) regions later showed normalized rCVR. Six regions (10%) remained decreased rCVR regions; no region did not worsen during the course of this study. Twenty-nine regions of both preoperative resting rCBF and rCVR decreased regions. Postoperatively, 18 regions (62%) normalized in regards to both rCVR and resting rCBF; in 4 regions (14%), only the resting rCBF was normalized. In the 24 decreased rCBF and normal rCVR regions, there were no hemodynamic alterations after PTA. Regions with decreasing rCVR are at high risk of future brain infarction. This study indicates that the risk of cerebral infarction was avoided by PTA in the low rCVR regions.