Chapter 23: Arterial Disease

KEY POINTS

1. Carotid intervention as a preventive strategy should be performed in patients with 50% or greater symptomatic internal carotid artery stenosis and those with 80% or greater asymptomatic internal carotid artery stenosis. Carotid intervention for asymptomatic stenosis between 60% and 79% remains controversial and is a function of an operator’s stroke rate. The choice of intervention—carotid endarterectomy versus carotid stenting—remains controversial; currently, carotid endarterectomy appears to be associated with lower stroke rate, whereas carotid stenting is more suitable under certain anatomic or physiologic conditions.

2. Abdominal aortic aneurysms should be repaired when the risk of rupture, determined mainly by aneurysm size, exceeds the risk of death due to perioperative complications or concurrent illness. Endovascular repair is associated with less perioperative morbidity and mortality compared to open reconstruction and is preferred for high-risk patients who meet specific anatomic criteria.

3. Symptomatic mesenteric ischemia should be treated to improve quality of life and prevent bowel infarction. Operative treatment—bypass—is superior to endovascular intervention, although changes in wire and stent technology have improved the results of mesenteric stenting in recent series.

4. Aortoiliac occlusive disease can be treated with either endovascular means or open reconstruction, depending on patient risk stratification, occlusion characteristics, and symptomatology.

5. Claudication is a marker of extensive atherosclerosis and is mainly managed with risk factor modification and pharmacotherapy. Only 5% of patients with claudication will need intervention because of disabling extremity pain. The 5-year mortality of a patient with claudication approaches 30%. Patients with rest pain or tissue loss need expeditious evaluation and vascular reconstruction to ameliorate the severe extremity pain and prevent limb loss.

GENERAL APPROACH TO THE VASCULAR PATIENT

Since the vascular system involves every organ system in our body, the symptoms of vascular disease are as varied as those encountered in any medical specialty. Lack of adequate blood supply to target organs typically presents with pain; for example, calf pain with lower extremity claudication, postprandial abdominal pain from mesenteric ischemia, and arm pain with axillo-subclavian arterial occlusion. In contrast, stroke and transient ischemic attack (TIA) are the presenting symptoms from middle cerebral embolization as a consequence of a stenosed internal carotid artery. The pain syndrome of arterial disease is usually divided clinically into acute and chronic types, with all shades of severity between the two extremes. Sudden onset of pain can indicate complete occlusion of a critical vessel, leading to more severe pain and critical ischemia in the target organ, resulting in lower limb gangrene or intestinal infarction. Chronic pain results from a slower, more progressive atherosclerotic occlusion, which can be totally or partially compensated by developing collateral vessels. Acute on chronic is another pain pattern in which a patient most likely has an underlying arterial stenosis that suddenly occludes; for example, the patient with a history of calf claudication who now presents with sudden, severe acute limb-threatening ischemia. The clinician should always try to understand and relate the clinical manifestations to the underlying pathologic process.