Atherosclerosis

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Atherosclerotic disease is the **most common etiology of chronic upper extremity arterial occlusive disease** in older adults and typically involves the **proximal great vessels**, particularly the **ostial/proximal subclavian artery** (and less commonly the innominate), followed by axillary/brachial disease. [@shadman2004] [@martin2025]

**Clinical clues suggesting hemodynamically significant subclavian/innominate disease**

- **Inter-arm systolic blood pressure (BP) difference >=15-20 mmHg**, diminished pulses, supraclavicular bruit. [@shadman2004]
- Vertebrobasilar symptoms with arm exertion suggests **subclavian steal** (see [[Cerebrovascular Disease|Ch. 7]]). [@shadman2004]
- Angina/ischemia in patients with a **LIMA****left internal mammary artery (LIMA)** coronary graft suggests **coronary-subclavian steal** and warrants prompt evaluation. [@angle2010]

**Indications for revascularization (typical)**

Revascularization is generally recommended for **symptomatic** lesions (rather than asymptomatic stenosis) and should be individualized based on anatomic severity, symptom mechanism, and procedural risk. [@esc2017]

Common indications include:

1. **Lifestyle-limiting arm claudication** attributable to subclavian/innominate stenosis/occlusion. [@esc2017]
2. **Critical hand ischemia** (rest pain, ulcers, tissue loss) when due to correctable proximal inflow disease. [@esc2017]
3. **Embolization** from a proximal lesion (ulcerated plaque or aneurysmal disease) with recurrent distal ischemic events. [@esc2017]
4. **Subclavian steal syndrome** with reproducible vertebrobasilar symptoms and confirmed hemodynamic steal physiology. [@shadman2004]
5. **Coronary-subclavian steal** in patients with LIMA grafts (symptomatic or high-risk anatomy). [@angle2010]
6. **Pre-emptive left subclavian artery (LSA) revascularization** may be indicated in selected patients undergoing [[Thoracic and Complex Aortic Disease|thoracic endovascular aortic repair (TEVAR)]] when coverage risks posterior circulation or spinal cord ischemia. [@matsumura2009]

**Treatment strategy (overview)**

- **Best medical therapy** (antiplatelet therapy, statin therapy, smoking cessation, BP/diabetes control) is mandatory in all patients because upper extremity atherosclerosis is a marker of systemic cardiovascular risk. [@hiatt2015] [@esc2017] [@martin2025]
- **Endovascular-first** (angioplasty +/- stenting) is commonly favored for focal proximal stenoses due to high technical success and low morbidity; open reconstruction is reserved for long occlusions, failed endovascular therapy, complex anatomy, or specific operative contexts. [@angle2010] [@rutherford2018-rutherford]