# Aortoiliac Occlusive Disease > Aortoiliac occlusive disease for NEET-PG Surgery: Leriche syndrome, TASC II, aortobifemoral bypass, kissing stents and Takayasu in the young. - Canonical URL: https://prepelephant.com/topics/neet-pg/surgery/aortoiliac-occlusive-disease - Exam / course: NEET-PG · Subject: Surgery - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-02 - Last updated: 2026-10-02 - How to cite: "Aortoiliac Occlusive Disease", PrepElephant, https://prepelephant.com/topics/neet-pg/surgery/aortoiliac-occlusive-disease ## Direct answer Buttock and thigh claudication with absent femoral pulses and erectile dysfunction — Leriche's triad — is the signature of atherosclerotic occlusion at the aortic bifurcation and iliac segments. The workup runs from ankle-brachial index (with thigh pressures to unmask proximal disease) through duplex to CT angiography, which maps the anatomy that the TASC II classification then sorts into four grades of extent — type A short focal lesions best served by balloon angioplasty with stenting (kissing stents at the aortic bifurcation for ostial disease), type D long aortoiliac occlusions best served by aortobifemoral bypass with five-year patency around 85-90%, and types B and C decided by centre expertise and patient factors. Extra-anatomic grafts (axillobifemoral, femorofemoral) serve the hostile abdomen or high-risk patient at lower patency. In a young Indian woman with arm and leg claudication, bruits and raised inflammatory markers, Takayasu arteritis — common in South Asia — replaces atherosclerosis as the working diagnosis and demands immunosuppression before or with revascularisation. Smoking cessation, antiplatelet and statin therapy underpin every choice. ## What you must remember - **Leriche's triad:** buttock or thigh claudication, absent femoral pulses, erectile dysfunction — from occlusion at the aortic bifurcation; often called the aortoiliac occlusion syndrome. - **Collateral anatomy:** chronic aortic occlusion is survivable through Winslow's pathway — the internal mammary to inferior epigastric to external iliac route — and the mesenteric arcades via the marginal artery of Drummond; these circuits explain the often-insidious onset. - **TASC II mapping:** type A — short iliac stenosis, endovascular; type D — extensive aortobiliac occlusion, surgery; B and C are zone-of-debate lesions matched to centre expertise. - **Aortobifemoral bypass:** the durability benchmark at roughly 85-90% five-year patency; specific risks include impotence from sympathetic plexus injury at the bifurcation, colonic ischaemia, and distal embolisation. - **Endovascular technique:** kissing stents — parallel stents from both iliacs into the distal aorta — for ostial bifurcation disease; covered stents favoured for recanalised chronic occlusions. - **Extra-anatomic options:** femorofemoral crossover for unilateral iliac occlusion, axillobifemoral for hostile abdomen — lower patency, lower operative stress. - **Takayasu arteritis:** the young Indian woman's disease — stenoses of aorta and branches with claudication, bruits, diminished pulses and active-phase inflammatory markers; immunosuppression precedes intervention to prevent restenosis. - **Differential discipline:** distinguish vascular claudication from neurogenic (spinal stenosis relieves with sitting, not standing; treadmill testing separates) and consider radiation arteritis and retroperitoneal fibrosis in the atypical. ## Two patients, two diseases A 58-year-old smoker limps 200 metres on flat ground with buttock and calf pain; femoral pulses are absent, ankle-brachial index 0.5, and CT angiography shows the aorta occluded from just below the renal arteries into both common iliacs with good distal runoff — TASC D. The consultation walks through aortobifemoral bypass (best patency, biggest operation, with impotence and other defined risks), bilateral iliac stenting (less durable across this extent), and the non-negotiables: stop tobacco, statin, antiplatelet, supervised exercise. Contrast a 24-year-old woman with arm and leg claudication, carotid and abdominal bruits, an absent radial pulse and a C-reactive protein that is elevated — this is Takayasu arteritis until imaging and inflammatory markers prove otherwise, and the treatment ladder begins with corticosteroids and immunosuppression, because stenting an inflamed vessel invites restenosis. The anatomy looks similar on the angiogram; the management barely overlaps — which is why age, sex and inflammatory markers lead the viva answer. ## Where students slip The triad gets quoted incompletely — erectile dysfunction is the forgotten third element and the one that completes the mark. TASC types are memorised as letters without treatment mapping; the examinable pairings are A with angioplasty and D with bypass. The collateral question (Winslow's pathway) separates prepared candidates from the rest. On Takayasu, students reach for the stent before suppressing the inflammation — the restenosis rate makes that an examinable error. Finally, candidates forget that thigh pressure measurement on the ankle-brachial study is what unmasks aortoiliac disease hiding above a normal calf pressure. ## Frequently asked questions ### What constitutes Leriche's triad? Buttock and thigh claudication, absent femoral pulses, and erectile dysfunction — from occlusive disease at the aortic bifurcation. Chronic onset is cushioned by collaterals. ### Which TASC II type is treated surgically? Type D — extensive aortoiliac occlusive disease — is the surgical indication, usually aortobifemoral bypass. Type A short lesions go to angioplasty; B and C depend on centre expertise. ### What are kissing stents? Parallel stents deployed from both iliac arteries into the distal aorta, reconstructing the bifurcation. They treat ostial disease at the aortic bifurcation endovascularly. ### Why does Takayasu arteritis matter in India? It is a leading cause of aortoiliac and branch occlusion in young South Asian women, mimicking premature atherosclerosis. Active disease needs immunosuppression before revascularisation. ### What patency does aortobifemoral bypass achieve? Around 85-90% at five years — the durability standard against which endovascular options are judged. Its price is a major abdominal operation with specific complications.