Accuracy of Common Femoral Artery Doppler Waveform Analysis in Predicting Haemodynamically Significant Aortoiliac Lesions TC26-TC28
Dr. Varsha P. Rangankar,
Associate Professor, Department of Radiology, SKN Medical College and GH, Pune-411 041, India.
Introduction: Doppler ultrasound is cost-effective and accurate noninvasive method for evaluation of peripheral arterial disease. However, there is difficulty in detection of aortoiliac lesions due to inadequate visualization of aortoiliac arteries in many patients. The Doppler waveform changes occurring distal to significant stenosis or occlusion are well documented. Accordingly, common femoral artery (CFA) Doppler waveform analysis may be used to predict haemodynamically significant proximal aortoiliac lesions. Aim To evaluate the accuracy of Doppler waveform analysis at the CFA for diagnosing haemodynamically significant aortoiliac stenosis or occlusion in patients of peripheral arterial disease.
Materials and Methods: A total of 67 patients (114 aortoiliac segments) with suspected peripheral arterial disease were retrospectively evaluated and labeled as normal or abnormal by analysing the Doppler waveform of CFA. The triphasic waveform with normal reversal pattern was categorized as normal, while low velocity biphasic or monophasic waveform were labeled as abnormal and indirect diagnosis of normal or diseased (>50% stenosis or occlusion) aortoiliac segment was made. The results were compared to intra-arterial angiography, considered as the gold standard.
Results: The Doppler waveform analysis of CFA was abnormal in 41 out of 114 common femoral arteries, while intra-arterial angiography showed significant stenosis (21 arteries) or occlusion (26 arteries) in 47 (41%) of 114 aortoiliac segments in 67 patients. Out of 67 normal aortoiliac segments seen on angiography, the CFA waveform analysis was interpreted as normal in 62 segments. An abnormal CFA waveform could diagnose significant aortoiliac lesion with 87% sensitivity, 92% specificity, 89% Positive Predictive Value (PPV), 91% Negative Predictive Value (NPV) and 90% accuracy using angiography as the gold standard. The low velocity monophasic waveform which was seen in 38 (33%) of 114 segments was reliable predictor of significant aortoiliac disease with 93% positive predictive value.
Conclusion: CFA Doppler waveform pattern analysis is a sensitive and accurate technique for the prediction of haemodynamically significant aortoiliac stenosis or occlusion.