Rationale: atheromatous stenosis of both renal arteries, or of the artery of a functionally solitary kidney is a frequent cause of renal failure in the elderly. Atheromatous Ischemic Renal Insufficiency (AIRI) can be ameliorated by surgery or angioplasty. However, such procedures can be hazardous in a patient with extensive aortic atheromatous plaques. This justified a study of the validity of Pulsed Doppler (PD), a diagnostic procedure less invasive than renal angiography in AIRI.
Objectives: to evaluate the diagnostic interest of PD in AIRI, using renal angiography as a criterion of adequacy.
Methods: renal arteries PD (Ultramak-4, 3.5 and 5 Mhz probes) followed by renal angiography (Seldinger). "Significant" stenosis = 50% on angiography. "Positive" PD = turbulences and/or acceleration.
Patients: 32 patients were investigated for suspected AIRI on the grounds of 1) age greater than 50; 2) atheromatous background and 3) renal insufficiency with no other evident etiology, or rapidly declining GFR in such a patient treated with ACE inhibitors.
Results: 16/32 angiographies disclosed significant stenosis of at least 1 renal artery. 56 renal arteries were investigated with both angio. and PD. Prevalence of stenoses was 16/56. PD had 93.7% sensitivity and 55% specificity. Positive predictive value was 45.5% and negative predictive value was 95.7%. Specificity was 80% when PD disclosed acceleration.
Conclusions: negative PD is sufficient argument to reconsider the indication of renal angiography in a high risk pt with suspected AIRI.