Prevalence of renal artery stenosis in flash pulmonary oedema: Determination using gadolinium-enhanced MRA

PurposeThe primary purpose was to determine the prevalence of renal artery stenosis (RAS) in patients presenting with acute (“flash”) pulmonary oedema (FPE), without identifiable cause using contrast-enhanced magnetic resonance angiography (CE-MRA) of renal arteries. A secondary goal was to correlate clinical parameters at presentation with the presence or absence of RAS.Materials and methodsPatients presenting with acute pulmonary oedema without identifiable cause prospectively underwent CE-MRA. > 50% renal artery stenosis was considered significant. Clinical parameters (blood pressure, serum creatinine, history of hypertension/hyperlipidaemia) were compared in patients with and without RAS using an unpaired t-test. Results expressed; mean (+/−SD).Results20 patients (4 male, 16 female, age 78.5+/−11 years) underwent CE-MRA. 9 patients (45%) had significant RAS (6 (30%) bilateral, 3 (15%) unilateral). Systolic BP was higher in patients with RAS (192+/−38 mm Hg) than those without (134+/−30 mm Hg) (p < .005). Diastolic BP was higher in patients with RAS (102+/−23 mm Hg) than those without (76+/−17 mm Hg) (p < .01). All patients with RAS and 6/11(55%) patients without RAS had a history of hypertension. No significant difference in creatinine or hyperlipidaemia history was observed.ConclusionThe prevalence of RAS in patients presenting with FPE is 45%. The diagnosis should be considered in patients presenting with unexplained acute pulmonary oedema, particularly if hypertensive at presentation.