From the Guidelines
Arterial thrombosis is primarily caused by atherosclerotic plaque rupture, thrombosis of a lower extremity bypass graft, or lower extremity embolism originating from the heart or a proximal arterial aneurysm, leading to tissue ischemia and infarction in the affected areas. The severity of acute limb ischemia depends on the location and extent of arterial obstruction and the capacity of the collaterals to perfuse the ischemic territory, as noted in the acc/aha 2005 practice guidelines 1. Arterial embolism is more likely than arterial thrombosis to cause sudden, severe, limb-threatening ischemia, and the clinical diagnosis of arterial embolism is suggested by the sudden onset or sudden worsening of symptoms, a known embolic source, and the absence of antecedent claudication or other manifestations of obstructive arterial disease 1.
Key Factors Contributing to Arterial Thrombosis
- Atherosclerotic plaque rupture
- Thrombosis of a lower extremity bypass graft
- Lower extremity embolism originating from the heart or a proximal arterial aneurysm
- Extrinsic local factors such as popliteal entrapment, cystic adventitial disease, or repetitive trauma
Clinical Manifestations
- Pain
- Paralysis
- Paresthesias
- Pulselessness
- Pallor
- A cold extremity (polar)
Importance of Prompt Recognition and Treatment
Prompt recognition and treatment of arterial thrombosis are essential to prevent permanent tissue damage and potentially life-threatening complications, as the longer the obstructive lesion, the more collateral pathways that are interrupted, and thrombosis tends to propagate proximally in an artery, up to the next large side branch 1. Systemic anticoagulation is a key component of treatment to prevent further thrombus propagation.
From the Research
Arterial Thrombosis Causes
- Arterial thrombosis is mainly associated with heightened platelet reactivity and damage to the vessel wall 2
- Risk factors for arterial thrombosis include:
- Smoking
- Hypertension
- Diabetes
- The metabolic syndrome
- Hyperlipidemia 2
- Atherosclerosis is a multifactorial vascular disease that develops in the course of a lifetime, and numerous risk factors for atherosclerosis have been identified, mostly inflicting pro-inflammatory effects 3
- Vessel injury, such as occurring during erosion or rupture of atherosclerotic lesions, triggers blood coagulation, which may drive thrombo-inflammatory mechanisms and lead to thrombosis 3
Shared Risk Factors
- Age is a shared risk factor for both arterial and venous thrombosis 2, 4
- The metabolic syndrome is also a shared risk factor for both arterial and venous thrombosis 2, 4
- High body mass index is associated with both myocardial infarction and venous thromboembolism 5
- Advancing age is associated with both myocardial infarction and venous thromboembolism, with a hazard ratio per decade of age of 2.34 for myocardial infarction and 1.87 for venous thromboembolism 5
Distinct Risk Factors
- Blood pressure, high levels of triglycerides and total cholesterol, low HDL cholesterol, self-reported diabetes, and smoking are associated with increased risk of myocardial infarction but not venous thromboembolism 5
- Cancer, surgery, pregnancy, and estrogens use are risk factors for venous thrombosis, but not typically associated with arterial thrombosis 2