Diagnostic tests for renal artery stenosis in patients suspected of havingrenovascular hypertension: A meta-analysis

Purpose: To summarize and compare the validity of computed tomography angio graphy, magnetic resonance angiography, ultrasonography, captopril renal sc intigraphy, and the captopril test for diagnosis of renal artery stenosis i n patients suspected of having renovascular hypertension. Data Sources: For each diagnostic modality, published studies were identifi ed by MEDLINE literature searches. Study Selection: Original studies were selected if they met the following c riteria: 1) suspicion of renovascular hypertension was the indication for t he test; 2) intra-arterial x-ray angiography was used as the gold standard; 3) a cutoff point for a positive test result was explicitly defined; and 4 ) absolute numbers of true-positive, false-negative, true-negative, and fal se-positive results were available or could be derived from the presented d ata. Data Extraction: A standard form was used to extract relevant data. Data Synthesis: Data on the accuracy of the different diagnostic methods we re analyzed and compared by constructing summary receiver-operating charact eristic (ROC) curves and by computing areas under the summary ROC curves. Results: Although accuracy varied greatly for all diagnostic modalities, su mmary ROC curves found that computed tomography angiography and gadolinium- enhanced, three-dimensional magnetic resonance angiography performed signif icantly better than the other diagnostic tests. Conclusions: Computed tomography angiography and gadolinium-enhanced three- dimensional magnetic resonance angiography seem to be preferred in patients referred for evaluation of renovascular hypertension. However, because few studies of these tests have been published, further research is recommende d.