​Kembara Xtra - Medicine - Peripheral Arterial Disease

​Kembara Xtra - Medicine - Peripheral Arterial Disease 
Atherosclerotic occlusive disease of the peripheral arteries, known as peripheral arterial disease (PAD), most frequently affects the lower limbs. PAD ranks third in terms of the primary cause of atherosclerotic vascular morbidity, after coronary artery disease and cerebrovascular disease. With a resting anklebrachial index (ABI) of less than 0.90, PAD is frequently diagnosed as intermittent claudication (IC) or unusual leg pain.


Epidemiology 
Age: 65 years, 50 to 64 years with atherosclerosis risk factors (e.g., hyperlipidemia [HLD], hypertension [HTN], history of smoking), or 50 years with DM and one additional atherosclerosis risk factor, or 50 years with DM and both HTN and DM.
People who have recognized atherosclerotic disease in another arterial bed, such as mesenteric artery stenosis or AAA, which affects at least 7.1 million people in the United States.
Incidence
Age and the existence of cardiovascular risk factors both increase incidence.
5.9% of Americans aged 40 or older have a low ABI (0.9), which indicates the presence of PAD, according to data from the National Health and Nutrition Examination Survey (1999-2004). However, the true prevalence of PAD is difficult to determine because more than half of those with a low ABI are asymptomatic.

Pathophysiology and Etiology 
The most frequent cause of arterial blockage in PAD is underlying atherosclerotic disease.
A lower ABI is a reliable independent predictor of the link between PAD and cardiovascular morbidity and mortality.
Additionally, phlebitis, trauma, and autoimmune/vasculitic disorders can be the cause of PAD.
 Reperfusion at rest following ischemia can result in numerous subsequent physiologic changes, including inflammation, oxidant stress, endothelial dysfunction, and mitochondrial injury. Arterial narrowing results in insufficient oxygen delivery to the muscle during periods of increased demand (i.e., exercise), causing claudication and limiting exercise.
Genetics
Although a number of the PAD risk variables (listed below) are heritable, genome-wide association studies have had less success isolating single nucleotide variants that are unique to PAD. The growing clinical and genetic variability of PAD has been blamed for this.

Older age, atherosclerotic disease of any vascular bed, smoking history or current use, diabetes mellitus, HTN, HLD, and chronic kidney disease (CKD) are risk factors. Heritable conditions include chylomicronemia, hypercholesterolemia, hyperhomocysteinemia, and pseudoxanthoma elasticum.


Statin medication is recommended for patients with clinical PAD for secondary prevention of atherosclerotic cardiovascular disease in addition to regular aerobic exercise programs, quitting smoking, controlling blood pressure (BP), and managing diabetes.


Accompanying Conditions 

Other atherosclerotic diseases like myocardial infarction (MI), transient ischemic attack (TIA), and cerebrovascular accident (CVA) are linked to PAD in addition to the risk factors outlined above.

20–40% of patients with the diagnosis won't have any symptoms.
Approximately 10–35% of people have classic IC, which is characterized by walking-related pain, aches, cramps, discomfort, or fatigue that is eased by rest.
 40–50% of patients experience unusual pain
In between 1% and 2% of patients, a limb is at risk of becoming critically ischemic.
 Ulcerations and wounds that don't heal
Skin color changes
Leriche syndrome, which is caused by extensive atherosclerosis of the femoral, popliteal, iliac, and distal abdominal aorta, is characterized by erectile dysfunction, IC, and absent or decreased femoral pulses.


clinical assessment 
Pale atrophic skin with hair thinning or loss (found with chronic PAD) Dependent rubor on leg elevation Brittle or hypertrophic nails
Reduced or absent extremities pulses might be a symptom of moderate to severe PAD.
On the distal toes or heels, severe PAD may cause sores and ulcers that may not heal.
• Gangrene
Lower extremities in the distance could feel cool.

Differential Diagnosis Peripheral neuropathy Spinal stenosis or nerve root compression (pseudoclaudication) Arterial aneurysm or dissection Deep vein thrombosis (DVT) Thromboangiitis obliterans (Buerger disease) or other vasculopathies Arterial embolism

Results from the Laboratory Screening
Current AHA/ACC guidelines advise resting ABI testing for symptomatic patients and state that it may be appropriate to test asymptomatic patients with increased risk of PAD (patients with known atherosclerotic disease or risk factors of atherosclerosis including DM, HTN, HLD, smoking, and age 65 years). Routine ABI screening for asymptomatic adults without PAD risk factors is not advised by the AHA/ACC and is graded as having insufficient evidence by the A
Initial examinations (lab, imaging)
Identification of risk factors using the basic metabolic profile and fasting lipid profile
Imaging should only be performed on patients who have lifestyle-limiting symptoms (IC) despite receiving adequate, guideline-directed treatment and therapy. Exercise treadmill ABI is helpful in people who are symptomatic but have normal resting ABI.
- In symptomatic patients who are being considered for revascularization, duplex ultrasound, magnetic resonance angiography (MRA), and computed tomography angiography (CTA) are advised.
- Patients with critical limb ischemia should consider invasive angiography, and candidates for revascularization with symptomatic PAD should also consider it.

Diagnostic Techniques/Other Toe-brachial index (TBI) is advised when ABI is 1.40, indicating a noncompressible vessel. Doppler ABI is the ratio of systolic blood pressure at the ankle and brachial arteries.
Test Interpretation: 0.90 abnormal, diagnostic of PAD; 0.91 to 0.99 borderline; clinically correlated; and seek more testing; 1.00 to 1.40 normal; >1.40 worry for incompressible arteries; relationship with diabetes mellitus.

Management A supervised exercise program, medicinal therapy based on guidelines, and risk factor reduction are all part of the multifaceted approach to treating PAD.
The following recommendations are mostly based on AHA/ACC Guidelines.
 Determine functional state using the Rutherford or Fontaine classification schemes. The Trans-Atlantic Inter- Society Consensus (TASC) determines the anatomic classification of complexity. It is possible to utilize this classification to direct management.
 Modification of cardiovascular risk factors, particularly in the context of smoking cessation
- High-intensity statin (lipid-lowering medication) has been found to minimize all-cause mortality and is advised for all patients with PAD. 1A.
- Aim BP 140/90 mm Hg
- In patients with PAD 1A, ACE inhibitors are significantly related with a decrease in major adverse cardiovascular events.
- Assistance with quitting smoking, including counseling, pharmacological interventions (such as varenicline, bupropion, and nicotine replacement therapy), and behavioral interventions.
The first course of treatment for patients with IC is advised to be supervised exercise training, which takes place in a hospital or outpatient facility. Patients are urged to walk for at least 30 to 45 minutes, three times per week, for at least 12 weeks (taking breaks as symptoms arise). When a supervised program cannot be implemented, a structured community or home-based exercise program is advised.
For the best results, an interdisciplinary team of medical professionals—including, if necessary, vascular specialists—nurses, exercise physiologists, podiatrists, nutritionists, and social workers is advised.

First Line of Medicine

Antiplatelet monotherapy is advised for PAD patients who don't have any bleeding risk contraindications. First-line antiplatelet medications like aspirin (75 to 325 mg) or clopidogrel (75 mg) are appropriate.
Antiplatelet monotherapy can be prescribed to asymptomatic patients with an ABI diagnosis of PAD. The effectiveness of antiplatelet treatment in asymptomatic patients with borderline ABIs (0.91 to 0.99) is not well established.
Dual antiplatelet treatment (DAPT; aspirin and clopidogrel) should only be provided after endovascular intervention because the evidence for its efficacy is unreliable and the risk of bleeding is elevated.
Statins are advised by the most recent professional organization guidelines for everyone with symptomatic and asymptomatic PAD.
The above drugs can be taken concurrently with the start of an exercise program. Cilostazol (100 mg orally twice daily) has been demonstrated to improve walking distance and should be evaluated in all individuals with claudication that impacts daily functioning.
Next Line
Pentoxifylline (400 mg three times daily) was once thought to be the first line treatment for claudication symptoms, but the effectiveness of this approach is questionable (Cochrane, other reviews).

Surgical Techniques 

Patients with a poor response to less intrusive treatments (such as exercise and medication), considerable claudication-related disability, and a positive risk-benefit ratio might explore percutaneous and surgical procedures.
In order to enlarge the stenosed arterial lumen through balloon angioplasty and potential stent insertion, percutaneous intervention entails gaining access to the artery with a wire or catheter. Drug eluting balloons and stents are possible.
 Favorable for aortoiliac illness patients and reasonable for femoropopliteal disease
Infrapopliteal lesions currently lack significant data, however ongoing research are comparing the effectiveness of surgical and endovascular treatments.
A bypass graft is used during surgery to revascularize the artery proximal to the stenosis.

Healthcare Alternatives 

Additionally, studies on Ginkgo biloba, L-arginine, propionyl-L-carnitine, omega-3 fatty acids, and vitamin E have been conducted; their efficacy is generally unknown. Chelation therapy and B-complex vitamins are not advised in patients with PAD. As a result, it is currently not advised to utilize them in the primary care setting.

Follow-Up Patients should have complete physical and history checks at the follow-up appointment. They should be questioned regarding their success in reducing risk factors (such as smoking, blood sugar management, and HTN), exercise endurance and program compliance, and the efficacy of medicines.
Patients should obtain routine symptom and occlusion assessment following endovascular or surgical intervention by resting and exercise ABIs.


Diet All individuals with PAD or atherosclerotic disease and risk factors should follow a heart-healthy diet.
The best diets are probably balanced ones with plenty of fruits, vegetables, nuts, lean protein, and healthy fats, like the Mediterranean diet.
When necessary, patients can benefit from nutritional advice.

Limb ischemia and IC prognosis: 15-20% of patients will experience worsening claudication, 5-10% will need endovascular or surgical intervention, and 2-5% will have an amputation (most frequently patients who smoke and those with diabetes).
In terms of cardiovascular outcomes, 20% of patients with PAD will have a cardiovascular event that is not fatal at 5 years, and 15% to 20% will pass away, most frequently from cardiovascular disease.

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