PubMed2000
PURPOSE: In the procedure of renal artery angioplasty, the angiographically measured degree of stenosis should be compared with the intraarterial transstenotic blood pressure gradient and pre-interventional Doppler findings. METHODS: In a total of 46 renal arteries in 35 patients with renovascular hypertension, the angiographic-morphological parameters: "linear", "geometric" and "densitometric" degree of stenosis are compared with the invasive transstenotic blood pressure gradient and the pre-interventional Doppler ultrasound. RESULTS: All angiographically determined degrees of stenosis ("linear", "geometric" and "densitometric") correlate--moderately--with the transstenotic blood pressure gradient (correlation coefficients: 0.67 ("linear"), 0.65 ("geometric") and 0.49 ("densitometric"), each versus systolic pressure gradient, respectively). Stenoses that are angiographically classified as "low grade" (< 50%) nevertheless have a high number of high transstenotic pressure gradients: 21 of 22 show systolic values > or = 10 mmHg, 13 of 22 even > or = 30 mmHg. All stenoses Doppler sonographically classified as "high or very high grade" (Vmax,syst > or = 3 m/s) are confirmed by angiography and/or pressure measurement. CONCLUSIONS: Angiography has the tendency to underestimate the degree of renal artery stenosis, especially in "low grade" stenoses (< 50%). However, in those > or = 50% a high transstenotic blood pressure gradient can be taken for granted. If the angiographic degree of stenosis seems uncertain, we recommend measurement of blood pressure gradient.