Intra-arterial Doppler flowmetry in the superficial femoral artery following angioplasty

Abstract.

The aim of the study was to assess the diagnostic value of an intravascular Doppler guidewire in patients with peripheral percutaneous angioplasty (PTA). The prognostic value was also evaluated. Measurements were done prior and following angioplasty in 22 patients with peripheral arterial occlusive disease. As additional therapy, stent insertion and peripheral (Aa. poplitea Ill/tibial) angioplasty was performed (4 patients per group). For stress testing, adenosinetriphosphate (ATP) was given intra-arterially. Follow-up was performed by angiography, colour-coded duplex ultrasound or judged by unequivocal clinical stage at follow-up to 13 months. Average (APV) and maximal peak velocity (MPV) increased following PTA, after additional treatment (peripheral PTA or stent), and after intra-arterial application of a vasodilator. Patients with peripheral lesions had markedly lower velocities prior treatment and following PTA after vasodilatation. Following peripheral PTA, the values were similar to the patients with PTA alone. Velocities after stenting were markedly increased in the stress condition. Of the 22 patients, 7 had a recurrent disease. The latter patients had higher velocities at rest prior to and following PTA. In stented lesions higher velocities seem to be linked with a worse outcome. The ratio between velocity prior to and after the application of the vasodilator seems to be of diagnostic importance. A ratio of 1.9 or more was of positive prognostic value. The Doppler guidewire is a practical and valuable tool in assessing technical success after angioplasty of peripheral lesions, critical or morphologically worse lesions. In our study the decision for stent application was made on the morphological image; however, increased velocity and changes in phasicity substantiated our decisions. Increased ratios prior to and after vasodilation (flow reserve) are of prognostic value and therefore suitable as indication for stent placement or tibial angioplasty.