[The concept of critical arterial stenosis: value of a model of measures obtained by an angiographic method and the Doppler technic before and after transluminal angioplasty of the iliac arteries].

INTRODUCTION

Numerous studies in the literature have proven the fact that a critical size appears during the stenosis evolution. The work presented is a non invasive approach of this value, with correlation to the invasive results. The study was realized on a homogeneous group of 23 arteriopathic patients, selected for iliac artery angioplasty procedure.

MATERIAL AND METHODS

Patients selection: twenty-three patients including 24 angioplasty procedures have been selected on a 21 month time study. Invasive data: two measurements are realized during angioplasty: trans-stenotic pressure gradient before and after angioplasty. stenosis calibration: both diameter and section have been calculated on radiological films. Non invasive data: a standard Doppler test is performed on lower limbs. Two parameters are compared with the invasive data: the ascending time of velocity curve at the common femoral level. the systolic pressure index (peripheral pressure/radial pressure).

RESULTS

1. Critical stenosis--invasive techniques (fig. 1): trans-stenotic pressure gradient versus stenotic measurements shaw an hyperbolic correlation. The critical stenotic level is found to be 60% in diameter and 80% in section. 2) Critical stenosis--non invasive techniques: stenotic measurements compared to ascending time (fig. 2) as well as pressure index at rest (fig. 3) shaw the same type of curve. The critical stenotic level is found to be the same than with invasive techniques.

DISCUSSION

Some discordant results open the discussion about angioplasty as a "gold standard", specially with a geometrical analysis. Bad precision in non regular stenosis. Hemodynamic consequences of turbulent stenosis are not evaluated. Clinical interest of critical stenotic notion is underlined.(ABSTRACT TRUNCATED AT 250 WORDS)