ORGANUM
PVD is driven by a progressive atheroscleotic disease resulting in the reduction of major organ blood flow and end-organ ischemia. The process of atherosclerosis is complex, with the involvement of numerous cells, proteins, and pathways. There are important risk factors to consider in the development of atherosclerosis:
Tobacco use/smoking
Highest risk: Odds ratio 2.7 (95% CI 2.4-3.1)
Diabetes mellitus
Hypertension
HIV
High cholesterol
Age > 50
Elevated homocysteine levels
BMI > 30
Family history of cardiovascular disease
Peripheral vascular disease affects 200 million people worldwide, including approximately 40 to 45 million americans. Over 20% of people over the age of 80 have PAD.
Data on gender differences is conflicting. In the Framingham study, intermittent claudication (IC) was more prevalent in men compared to women (1.9% to 0.8%; ratio 2.38). This finding was consistent with the Rotterdam study that found men were 1.83 times more likely to have IC, with a prevalence of 2.2% in men and 1.2% in women. However, a gender shift in prevalence occurs when the diagnosis of PAD is based on the ankle-brachial pressure index (ABI). For example, the Rotterdam study found the prevalence of ABI-based diagnosis of PAD to be 20.5% in women and 16.9% in adults, with a ratio of 0.82.
Intermittent claudication is the most classic symptom - exercise inducing cramping sensation with fatigue, weakness or pressure. Patients may deny pain and therefore asking about discomfort is more useful. Symptoms are worsened by leg elevation and relieved by placing the limb in a dependent position. Paraestheisa, lowrr extremity weakness, stiffness and cool extremities may also be present. The area of obstruction is usually seen one level above the area of discomfort - patients with narrowing of the aortoiliac region will have button and thigh symptoms. Patients may also have the inability to get leg hair.
The diagnosis of PVD can be difficult due to the increasing prevalence of similarly presenting comorbid conditions and many patients having an asymptomatic or atypical presentation. The clinical presentation of PAD depends on severity of arterial insufficiency, and presence of comorbid conditions which may alter or mask the underlying symptoms of PAD. Atypical presentations may occur in patients have lumbosacral disease, spinal stenosis, or advanced diabetes mellitus; all which may alter the perception of pain.
Pseudo claudication refers to neuropathic pain observed in patients with spinal stenosis can be differentiated from PAD with history and physical examination; it is characterised by weakness and paresthesia that is irrespective of the degree of physical activity and usually is relieved by sitting down or changing body positionings rather than rest.
A proportion of patients may progress through debilitating ischemic rest pain, critical limb ischemia and eventual amputation. Erectile dysfunction may also be seen. Critical limb ischemia is typically a result of thrombosis (80%-85%), and PAD increases the risk of this. Embolism occurs in 10-15%, and arises from a thrombus in the left atrium/mural thrombosis (following an MI). It presents with the six Ps:
Pain
Pallor
Pulselessness
Poikilothermia (Coldness)
Paraesthesia
Paralysis
Measurement of ankle-brachial index (ABI) is a cost-effective noninvasive objective measure of PAD diagnosis. ABI is obtained by measuring the systolic ankle pressure ratio to the systolic brachial pressure.
>1.3
Abnormal hardening from PVD (diabetes/renal failure)
0.9 - 1.2
Normal ABI
< 0.9
PAD
<0.4
Critical limb ischemia
Patients may have diminished or absent lower extremity pulses. Doppler studies can be done for sites of blood flow occlusions and flow velocities. In addition, CT angiography and MRA can help determine the sites of occlusion and assess if the patient is a candidate for angioplasty or bypass surgery.
Initially, improving cardiovascular risk via controlling hypercholesterolemia and lowering blood pressure, alongside lifestyle changes should be the mainstay of treatment. Cilostazol, an antiplatelet agent, can be used to cause vasodilation and suppresses the proliferation of vascular smooth muscle cells. If there is a potential response, it occurs within 12 weeks. Cilostazol cannot be used in patients with congestive heart failure.
Balloon angioplasty and stents can be used a provides a minimally invasive percutaneous treatment option for patients with PAD symptoms that does not respond to exercise or medical therapy. Endovascular treatments are best in patients with focal occlusive lesions in the iliac and superficial femoral arteries. Patients with long-segment total occlusions and infrapopliteal arterial occlusive disease see a decrease in success within surgical intervention. Bypass grafts can also be used to divert flow around the blockage or endarterectomy to segmentally remove the obstructive plaque.
Prognosis is highly dependent on lifestyle changes; if there is none, the disease is likely progressive. In addition, most patients with PAD also have coexistence of cardiovascular or cerebrovascular issues, which increases mortality rate. Outcomes in women tend to be worse due to smaller diameters of the arteries alongside a higher risk of developing complications and embolic events.
DVT
Radiculopathies/Spinal cord issues
Superficial thrombophlebitis
Raynaud phenomenon
Thromboangiitis obliterans (Buergers disease)
Sciatic