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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Aged, Aged, 80 and over, Angioplasty, Balloon, Arterial Occlusive Diseases, Blood Flow Velocity, Female, Femoral Artery, Follow-Up Studies, Graft Occlusion, Vascular, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Multivariate Analysis, Predictive Value of Tests, Stress, Mechanical, Treatment Outcome, Ultrasonography, Doppler, Duplex.
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Is high wall shear stress measured by magnetic resonance a predictor of restenosis in the femoral-artery after balloon angioplasty? Context: Wall shear stress (WSS) has been implied in the pathogenesis of restenosis after percutaneous transluminal angioplasty (PTA). Aims of the present study were to calculate WSS in the superficial femoral artery (SFA) from magnetic resonance imaging (MRI) and from duplex sonography in healthy controls and in patients after PTA of the SFA to evaluate the predictive value of WSS for restenosis. WSS was assessed by calculating the slope of velocity profiles at the vessel wall from data obtained with velocity encoded cine MR and with duplex using the formula: Shear stress=4xblood viscosityxpeak blood velocity/internal diameter. Seventeen patients were studied 1 day after successful PTA of the SFA. Restenosis was determined by duplex ultrasound at the 6-months follow-up visit. In healthy controls WSS values calculated from MRI and from duplex were similar (1.86+/-0.35 N/m2 vs 1.88+/-0.34 N/m2, n.s.). In patients the values obtained with duplex were higher than those obtained with MRI (4.1+/-2.3 N/m2 vs 2.4+/-1.2 N/m2, p=0.002). With both methods post-interventional WSS was higher in patients developing restenosis (duplex 5.4+/-2.2 N/m2, MRI 3.1+/-0.9 N/m2) than in those without restenosis (duplex 2.7+/-1.4 N/m2, MRI 1.5+/-0.7 N/m2) and was revealed to be an independent predictor of restenosis (p=0.03).
assistant
This is the first study demonstrating that increased post-interventional WSS in the SFA is predictive for restenosis. WSS values obtained with MRI and duplex were different in patients, however with both methods higher WSS was associated with restenosis. Final Decision: yes