Increased prostacyclin production after percutaneous transluminal angioplasty of the iliac artery for atherosclerosis obliterans
Onohara, T.; Fujinaga, Y.; Komori, K.; Sugimachi, K.
Panminerva Medica 41(1): 1-4
1999
ISSN/ISBN: 0031-0808 PMID: 10230247 Document Number: 501752
Background. Endothelial prostacyclin production is modulated by blood flow (wall shear stress). Local plasma prostacyclin concentrations and hemodynamic parameters have therefore been investigated in patients with atherosclerosis obliterans before and after angioplasty. Methods. Design: prospective study. Setting: department of Surgery, Matsuyama Red Cross Hospital, Matsuyama, Japan. Patients: nine lower limbs in eight patients with significant stenoses of the iliac artery were studied. Interventions: blood samples were obtained from the femoral artery and femoral vein of nine lower limbs undergoing percutaneous balloon angioplasty of the iliac artery. Measures: prostacyclin concentrations, radioimmunoassayed as 6-keto-prostaglandin F1alpha, were measured before and after balloon dilatation. Femoral blood flow and the ankle-brachial pressure index (ABI) were measured using a Doppler velocimeter before and after the procedure. The femoral blood flow waveform was used to calculate the meanblood flow and shear stress variation. Results. Before angioplasty, the mean (+-SEM) plasma prostacyclin concentration was 21.6+-1.5 pg/ml in the femoral artery and 25.4+-1.1 pg/ml in the femoral vein. After angioplasty, these values increased to 25.6+-2.2 pg/ml (p<0.05) and 32.8+-1.8 pg/ml (p<0.01), respectively. The pre-procedural ABI, mean flow rate, and shear stress variation were 0.596+-0.071, 354.1+-63.3 ml/min, and 69.1+-9.9 dyne/cm2, respectively. Both ABI and shear stress variation increased after angioplasty to 0.738+-0.076 (p<0.05) and 111.1+-24.2 (p=0.0775) dyne/cm2, but the mean flow rate (287.1+-61.1 ml/min after angioplasty) did not increase (p=0.2002). Conclusions. These results suggest that prostacyclin production increases after angioplasty, possibly due to increases in the intraluminal pressure and shear stress variation. This enhanced prostacyclin production may help to maintain arterial or bypass graft patency.