Introduction

Leriche syndrome, commonly referred to as aortoiliac occlusive disease (AIOD), is a product of atherosclerosis affecting the distal abdominal aorta, iliac arteries, and femoropopliteal vessels.[1] Leriche syndrome was first described in 1914 by Robert Grahman, but it was not until later that the symptoms were documented as a syndrome by Henri Leriche, a French surgeon and physiologist. The extent and localization of atherosclerotic occlusions relative to these arteries determine the classification of the disease.

AIOD is classified as Type I when confined to the distal abdominal aorta and common iliac arteries, Type II when predominately distal abdominal aorta with disease extension into common iliac and external iliac arteries, and Type III when affecting the aortoiliac segment and femoropopliteal vessels.[2] AIOD, when symptomatic, classically presents with a triad of claudication, impotence, and absence of femoral pulses. Claudication refers to cramping leg pain reproducible with exercise. 

Etiology

Leriche syndrome is caused by atherosclerosis. Modifiable risk factors for atherosclerosis include hypertension, diabetes mellitus, smoking, hyperlipidemia, hyperglycemia, and hyperhomocysteinemia. Non-modifiable risk factors for atherosclerosis include age, gender, ethnicity, and family history.[3]

Epidemiology

Ten percent of patients with peripheral arterial disease (PAD) may be asymptomatic, so the exact prevalence and incidence of Leriche syndrome are unknown. However, the prevalence of PAD increases with age. The prevalence of PAD is 14% for patients older than 69.[4] Additionally, AIOD is more prevalent among men and non-Hispanic Black individuals.

Pathophysiology

Leriche syndrome occurs secondary to atherosclerotic-induced arterial wall injury, leading to 2 out of 3 factors involved in Virchow triad, endothelial damage, and thrombosis. Once endothelial damage occurs, a resultant inflammatory response leads to lipid accumulation in smooth muscle cells and macrophages, eventually forming a plaque in the arterial lumen. Eventually, aortoiliac segments become more than 50% stenotic, and the resultant oxygen debt during exercise causes claudication. Once PAD becomes extensive in the aortoiliac segment, the majority of men with Leriche syndrome present with impotence and sexual dysfunction secondary to reduced penile arterial flow.[3]

History and Physical

Patients commonly present with claudication, which is cramping in the lower extremities (hips, thighs, buttocks) reproducible by exercise. A detailed history is essential in determining symptoms' location, severity, and duration. While impotence and sexual dysfunction may occur in the majority of patients, the hallmark of Leriche syndrome is reduced or absent femoral pulses.[2] However, due to collateral vasculature, limb-threatening ischemia is not universal.[5]

Evaluation

A serum lipid profile (total cholesterol, LDL, HDL, TG) and HbA1c (if the patient is diabetic), lipoprotein A, and homocysteine levels should be obtained.[3] An ankle-brachial index (ABI) should also be performed to evaluate the perfusion of the lower extremities. An ABI is often the first screening test performed as it is non-invasive, inexpensive, and reliable. An ABI provides the ankle systolic blood pressure ratio divided by the brachial systolic blood pressure detected using a Doppler probe. An ABI lower than 0.9 is considered abnormal and indicates the patient has PAD significant enough to cause claudication.[6] Duplex ultrasonography and CTA are performed to determine the location and degree of stenosis while planning an intervention.[5] Coronary artery disease is seen in 10% - 71% of patients with PAD, so obtaining an EKG as well to rule out coronary artery disease is recommended.[4]

Treatment / Management

Surgical treatment options for Leriche syndrome include thromboendarterectomy, aortobifemoral bypass (AFB), and percutaneous transluminal angioplasty (PTA) with or without stenting.[7][3][8] AFB is preferred over TEA, mainly when intervention is necessary for arteries deep in the pelvis. Long-term patency of surgically repaired vessels in AFB has been recognized as superior to thromboendarterectomy and PTA with or without stenting in surgically fit patients. The long-term patency rates of AFB approach 85-90% at 5 years and 75-80% at 10 years.[3] PTA and stenting are the interventions of choice in patients with multiple comorbidities, particularly those resulting in reduced lung function. Medical management includes smoking cessation, management of diabetes, antiplatelet, and statin therapy, in addition to antihypertensive therapy. Implementation of a walking exercise program has been shown to improve walking ability by 50% - 200%. The exercise program should consist of daily 30-minute walking sessions. Intolerable claudication pain should be the endpoint for each session.[9] Smoking cessation and lowering glucose and lipid levels (LDL <100 mg/dL and HbA1c below 7%) are primary objectives of medical management. Cilostazol, a phosphodiesterase III inhibitor, may be administered to treat the patient's claudication symptoms. Cilostazol may also have benefits in graft patency and prevention of stenosis.[10] 

Differential Diagnosis

Numerous vascular conditions can mimic the symptoms of Leriche syndrome and must be considered in the differential diagnosis. Arterial dissection, particularly in the iliac arteries, may cause claudication and absent femoral pulses, mimicking the symptom profile of Leriche syndrome.[11] The presence of rest pain and a definitive time course of symptom onset would be useful in delineating the underlying pathology in conjunction with ultrasound and arteriographic imaging. Patients who have recently undergone instrumentation and graft placement are at increased risk for dissection and acute occlusion. Critical limb ischemia is not often seen in Leriche syndrome, as its time course allows for the development of collateral vasculature. Signs of critical limb ischemia include sudden onset of pain in the affected extremity, paresthesias, paleness or coolness, and severely diminished or absent pulses.[12] Occlusion may result from thrombosis, emboli from a more proximal vascular region, or dissection. 

Prognosis

Without treatment, the prognosis of Leriche syndrome is poor. However, with modern medicine, outcomes are good. In some cases with slow progression or onset of Leriche syndrome, collaterals may develop as a self-compensating mechanism.[13]

Complications

Limb ischemia is a potential complication of Leriche syndrome, as well as heart failure, myocardial ischemia/infarction, gangrene, and even death.[14][15][16][17]

Consultations

If May-Thurner syndrome is suspected, a vascular surgery or interventional cardiology consultation should be obtained.

Deterrence and Patient Education

All patients should be encouraged to prevent/treat all modifiable risk factors.

Pearls and Other Issues

With the complexity of Leriche syndrome, it is highly recommended a purposeful interprofessional team be involved when Leriche syndrome is suspected.[18] Team members should include the patient's primary care physician, a cardiologist, an imaging specialist, a vascular surgeon, as well as an interventional cardiologist. The advantages of a team approach are that it can appropriately manage Leriche syndrome and improve patient satisfaction and the success of the intervention.

Enhancing Healthcare Team Outcomes

Multiple studies have investigated the benefit of utilizing an interprofessional team to enhance patient satisfaction and healthcare outcomes; the results are stunning. In light of this new evidence, it is now recommended that all institutions involved in percutaneous or cardiothoracic interventions should set algorithms in place and encourage interprofessional communication.[18] Many institutions have complied with this recommendation by engaging in interprofessional conferences to discuss complex cases. In the case of Leriche syndrome, an interventional cardiologist and a cardiothoracic surgeon should be involved to ensure the best management option is undergone in a case-by-case manner.