Leriche syndrome: A closer look at a rare and critical aortoiliac occlusion

Abstract

Collateral pathways in aortoiliac occlusive disease play a crucial role in maintaining blood flow to the abdomen, pelvis, and lower limbs. These pathways include systemic-to-systemic, visceral-to-visceral, and systemic-to-visceral connections. CT angiography is the primary imaging modality for diagnosing aortoiliac occlusion, offering detailed visualization of stenotic arteries and collateral pathways, particularly when enhanced by 3D reconstruction. This case report presents a 65-year-old male with poorly controlled hypertension, type 2 diabetes, and a 45-pack-year smoking history, who presented with progressively worsening claudication and rest pain. Imaging revealed thrombotic occlusion of the infrarenal aorta extending into the iliac arteries, with the development of collateral pathways. We also discuss the impact of erectile dysfunction severity and highlight evolving endovascular treatments such as CERAB, which show promising outcomes. This article aims to familiarize radiologists with the common patterns of aortoiliac occlusion and the associated collateral arterial pathways visible on CT angiography.

Introduction

Aortoiliac occlusive disease (AIOD), also known as Leriche syndrome, results from atherosclerotic narrowing or blockage of the distal abdominal aorta and iliac arteries. First noted by Robert Graham in 1814, it was later defined as a clinical syndrome by Henri Leriche, a French surgeon, who identified its hallmark triad: claudication, erectile dysfunction, and diminished or absent femoral pulses. The classification of the disease depends on the location and extent of arterial occlusions [1,2]. Multidetector computed tomography angiography (MD-CTA) with three-dimensional reconstruction is the diagnostic imaging modality of choice for a comprehensive evaluation of aortoiliac disease. It allows precise assessment of the extent of aortoiliac occlusion, delineation of collateral arterial pathways, and aids in treatment planning through advanced image postprocessing techniques [3].

Case report

A 65-year-old Black male with uncontrolled hypertension, type 2 diabetes managed with oral antidiabetics, and a 45-pack-year smoking history presented with intermittent claudication in both lower limbs. Over the past 2 years, the pain, initially exertional, progressively worsened and began occurring even at rest, particularly at night, significantly impacting his quality of life. He also reported long-standing erectile dysfunction, noted to be complete, suggesting vascular insufficiency.

Upon admission, his vital signs were stable, with a blood pressure of 138/80 mmHg, pulse rate of 84 beats per minute, respiratory rate of 18 breaths per minute, and oxygen saturation of 98%. Physical examination revealed absent pulses in the popliteal, dorsalis pedis, and posterior tibial arteries bilaterally, cold extremities, and ulcers on the dorsal foot. Based on WIfI classification, the patient’s wound was stage 2, ischemia stage 2, and foot infection stage 1. Delayed capillary refill and signs of chronic ischemia were also observed. Despite these findings, sensory and motor functions remained intact.

Laboratory results showed elevated CRP (70), indicating chronic inflammation, as well as elevated CK (230 U/L) and CK-MB (108 U/L), suggesting muscle damage. His lipid profile revealed significant dyslipidemia, with total cholesterol at 300 mg/dL, LDL at 100 mg/dL, and HDL at 40 mg/dL.

Abdominal CT and coronal MIP imaging revealed calcified plaques in the distal abdominal aorta and its branches (Fig. 1). CTA confirmed TASC D thrombotic occlusion of the infrarenal aorta extending into the iliac arteries, with robust collateral pathways (Fig. 2). A diagnosis of Leriche syndrome was made. The patient was started on medical therapy, including antiplatelets, statins, and antihypertensives, while being counseled on smoking cessation and follow-up care.

Fig. 1.

Coronal MIP (A) and volume-rendered (B) CTA images showing thrombotic occlusion of the infrarenal aorta (yellow arrow) with extension to the bilateral iliac arteries. Collateral pathways involving the internal iliac arteries (blue arrow), inferior epigastric arteries (red arrow), and spermatic arteries (green arrow) supplying blood to the occluded regions.

Fig. 2.

Abdominal CT with arterial phase enhancement (A) and coronal MIP (B) showing calcified plaques within the distal abdominal aorta and some of its branches (yellow arrow).

Discussion

Leriche syndrome is primarily a result of atherosclerosis, influenced by both modifiable and non-modifiable risk factors. Modifiable risk factors include arterial hypertension, diabetes mellitus, smoking, dyslipidemia, hyperglycemia, and elevated homocysteine levels. Non-modifiable factors comprise age, gender, ethnicity, and a family history of cardiovascular diseases [2,3]. Poor glycemic control in diabetes accelerates endothelial dysfunction and promotes atherosclerosis, further increasing the risk of AIOD.

AIOD, which is the underlying cause of Leriche syndrome, is particularly more common in men and non-Hispanic Black populations, as evidenced by our case involving a Black male patient [4].

The condition typically affects the aortoiliac segment, with the infra-inguinal arteries usually spared. It starts with stenosis of the distal abdominal aorta or common iliac arteries and can progress proximally or distally. Leriche syndrome can present in four forms: (a) isolated iliac artery stenosis, (b) stenosis at the aortic bifurcation, (c) combined stenosis of the aorta and iliac arteries (as seen in our case), and (d) complete occlusion of the infrarenal aorta [5].

Leriche syndrome may remain asymptomatic if arterial flow is maintained through collateral circulation. Symptomatic patients often experience pain, paresthesia, paralysis, pulselessness, pallor, weakness, or impotence. Pain is typically located in the hips and buttocks, often associated with a weak or absent femoral pulse [6]. The degree of erectile dysfunction correlates with the extent of occlusion and adequacy of collateral circulation.

Ultrasound is often the first-line imaging modality. In our case, Doppler findings confirmed proximal obstruction via a tardus parvus waveform and reduced peak systolic velocities. Ultrasound can also aid in post-procedural monitoring.

MRI angiography may be an alternative for patients with contraindications to CTA.

CT angiography of the abdomen and lower extremities is the preferred diagnostic imaging modality for managing AIOD [6]. It provides high spatial resolution and rapid imaging, allowing for precise identification of occlusion sites, detection of atherosclerosis, visualization of collateral pathways, and determination of the optimal segments for stent graft placement [[7], [8]].

Advanced imaging, such as 3D volume-rendered images, maximum intensity projections (MIP), and multiplanar reformations (MPR), helps assess the extent of AIOD and collateral circulation. MIP images may require oblique projections to capture 3D anatomical details accurately [7].

Differential diagnoses for Leriche syndrome include aortic dissection, primary and secondary aortic occlusion, neurogenic claudication due to spinal stenosis, deep vein thrombosis (DVT), aortoiliac aneurysms, and acute limb ischemia. A thorough clinical evaluation, including ABI testing, Doppler ultrasound, and CTA, is critical for accurate diagnosis [9].

Without treatment, the prognosis of Leriche syndrome is poor. However, the gradual progression may allow the development of collateral circulation to compensate for reduced blood flow. Potential complications include limb ischemia, myocardial infarction, gangrene, and death in severe cases [10].

Treatment typically begins with medical management, including lifestyle modifications, antiplatelet therapy, and control of underlying conditions like hypertension or diabetes. If medical therapy is insufficient, revascularization procedures such as endovascular intervention or open surgery are considered [[8], [11]]. Recent advances, particularly the CERAB technique (Covered Endovascular Reconstruction of the Aortic Bifurcation), offer promising mid- to long-term patency rates with favorable functional outcomes and reduced perioperative morbidity. This technique may significantly improve patient quality of life and challenge older paradigms of surgical management [12].

Conclusion

AIOD is frequently underdiagnosed and depends on collateral pathways for blood flow compensation. Failing to identify these pathways during surgery can cause severe complications like critical limb ischemia. CT angiography, along with maximum intensity projection and multiplanar reconstructions, is crucial for assessing AIOD and its collateral circulation. Radiologists must be familiar with both common and rare occlusion patterns and collateral pathways for accurate interpretation. Incorporating newer techniques like CERAB and functional assessments such as WIfI may enhance diagnostic precision and guide personalized therapeutic approaches.

Patient consent

Written informed consent for publication was obtained from patient.