Medical Management of Peripheral Arterial Disease (PAD)

1. Antithrombotic Therapy

Antiplatelet Agents

• Aspirin 75-325 mg/day - a COX-1 inhibitor, the most widely used agent
• Clopidogrel 75 mg/day - a P2Y12 receptor antagonist; in the CAPRIE trial, clopidogrel was superior to aspirin in symptomatic PAD patients (3.71% vs. 4.86% annual event rate). Clopidogrel is preferred in current smokers, as it has shown greater event reduction vs. aspirin in this group
• Ticagrelor 90 mg twice daily - In the EUCLID trial, ticagrelor showed similar benefit to clopidogrel monotherapy (HR 1.02); may have a role in poor clopidogrel metabolizers

Dual Antiplatelet Therapy (DAPT)

• DAPT (aspirin + P2Y12 antagonist) was NOT shown to reduce MACE more than aspirin alone in PAD in the CHARISMA trial, and increases bleeding risk
• Exception: In PAD patients with a prior MI, adding ticagrelor to low-dose aspirin reduced both MACE and major adverse limb events (MALE) in PEGASUS-TIMI 54
• DAPT is commonly used after peripheral endovascular interventions, though clear supporting trial data are limited

Low-Dose Oral Anticoagulation (Pathway Antithrombotic Strategy)

• Rivaroxaban 2.5 mg twice daily + aspirin is supported by two major trials:
  • COMPASS trial: In 6,391 PAD patients, this combination reduced MACE (5.1% vs. 6.9%, p=0.005) and MALE (1.5% vs. 2.6%, HR 0.57) vs. aspirin alone
  • VOYAGER-PAD trial: In 6,564 patients post-revascularization, rivaroxaban + aspirin reduced a composite of acute limb ischemia, major amputation, MI, stroke, and cardiovascular death (HR 0.85, p=0.009)
  • A meta-analysis of both trials confirmed superiority of the combination over aspirin alone for cardiovascular and limb events
• Major bleeding was increased with rivaroxaban, though fatal/critical organ bleeding was not significantly different
• Recommendation: Aspirin + low-dose rivaroxaban is reasonable in patients without elevated bleeding risk; full-dose anticoagulation is NOT routinely recommended as benefit does not outweigh bleeding risk

Vorapaxar

• A PAR-1 (thrombin receptor) antagonist approved for reducing thrombotic cardiovascular events in patients with a history of MI or PAD
• Contraindicated in patients with prior intracranial hemorrhage due to increased major bleeding risk

2. Lipid-Lowering Therapy

• Target: LDL < 70 mg/dL
• Agents: Rosuvastatin 40 mg/day or simvastatin 80 mg/day (though simvastatin 80 mg carries myopathy risk)
• Statins reduce mortality, MACE, MALE, and improve symptomatic outcomes. They also have pleiotropic effects: improved endothelial function, smooth muscle proliferation inhibition, plaque stabilization, and reduced platelet aggregation
• A VA population-based study of 155,647 patients showed high-intensity statin at PAD diagnosis significantly reduced limb loss and mortality

1. Add ezetimibe (reduces intestinal LDL absorption, proven to lower cardiovascular events)
2. Add PCSK9 inhibitors (e.g., evolocumab, alirocumab) if LDL goal still not reached - these monoclonal antibodies upregulate hepatic LDL receptors and have demonstrated reduction in MACE and major adverse lower extremity events

3. Blood Pressure Control

• Primary goal: reduce MACE
• ACE inhibitors are preferred - in the HOPE trial, ramipril reduced MI, stroke, and cardiovascular death by 25% vs. placebo in PAD patients
• Angiotensin receptor blockers (ARBs) are an alternative - In ONTARGET, telmisartan showed similar efficacy to ramipril with less angioedema
• Target BP: SBP < 140 mmHg, DBP < 90 mmHg (lower targets increasingly supported by cardiology guidelines)
• Importantly: beta-blockers are NOT contraindicated in PAD and may be used for concurrent cardiac indications

4. Glycemic Control (Diabetic Patients)

• DM significantly accelerates PAD progression; severity of disease correlates with chronic glucose exposure
• HbA1c target: <7% recommended by Global Vascular Guidelines for CLTI; <8% suggested by IWGDF to avoid hypoglycemia - individualize based on patient factors
• SGLT2 inhibitors (e.g., empagliflozin, dapagliflozin): reduce cardiovascular mortality, heart failure, renal complications, MACE, and amputation
• GLP-1 receptor agonists (e.g., semaglutide, liraglutide): similar cardiovascular and renal benefits
• Tight glycemic control reduces microvascular complications short-term and macrovascular complications when sustained over decades

5. Symptom Management - Intermittent Claudication

Cilostazol

• Cilostazol 100 mg twice daily is a Class I recommendation (ACC/AHA) for intermittent claudication
• Mechanism: reversible PDE-IIIa inhibitor - causes vasodilation and inhibits platelet aggregation (increases cAMP in platelets and vascular smooth muscle)
• Based on a Cochrane review of 16 RCTs: significantly improves pain-free and maximum walking distance
• Key contraindication: Congestive heart failure of any severity (class effect of PDE3 inhibitors)
• Common side effects: headache, palpitations, diarrhea, dizziness (main reasons for noncompliance)
• Should NOT substitute for aspirin/clopidogrel in ACS patients with concurrent PAD

Pentoxifylline

• No longer recommended - removed from guidelines due to lack of demonstrated benefit

6. Smoking Cessation

• Assess smoking status at every visit
• Pharmacologic options (used alone or in combination):
  • Varenicline (most effective)
  • Bupropion
  • Nicotine replacement therapy (patches, gum, lozenges)
• Intensive smoking cessation intervention (behavioral + pharmacologic) resulted in 21.3% vs. 6.8% success at 6 months compared with minimal intervention

7. Supervised Exercise Therapy

• A Cochrane review of 32 RCTs (1,835 IC patients): exercise improved both pain-free and maximum walking distance vs. placebo/usual care
• A meta-analysis of 25 RCTs: supervised treadmill exercise improved walking performance by ~180 m vs. no exercise
• Since 2017, CMS covers up to 36 sessions over 12 weeks for PAD patients with walking impairment
• Protocol: Minimum 45-60 minutes, 3 times/week for 12 weeks; intensity sufficient to elicit claudication
• Home-based walking is a reasonable alternative for those without access to supervised programs

Summary Table

Peripheral Arterial Disease - Medical Management

1. Antithrombotic Therapy

Single Antiplatelet Therapy (SAPT) - First Line for All Symptomatic PAD

• Asymptomatic PAD: SAPT reasonable if reduced ABI + low bleeding risk, given high prevalence of subclinical CAD
• USPSTF 2022 guidance against aspirin for primary prevention in the general population does not override clinical judgment in established PAD

Dual Antiplatelet Therapy (DAPT)

• Aspirin + clopidogrel: NOT superior to aspirin alone in PAD (CHARISMA trial) and increases bleeding
• Exception: Aspirin + ticagrelor in PAD patients with prior MI reduces MACE and MALE (PEGASUS-TIMI 54)
• Commonly used post-peripheral intervention, though RCT data are limited

Low-Dose Anticoagulation (Vascular Dose Strategy)

• Rivaroxaban 2.5 mg BID + aspirin (COMPASS trial):
  • In 6,391 PAD patients: reduced MACE (5.1% vs. 6.9%, p=0.005) and MALE (HR 0.57)
• Rivaroxaban 2.5 mg BID + aspirin (VOYAGER-PAD trial):
  • In 6,564 post-revascularization patients: reduced composite of ALI, major amputation, MI, stroke, CV death (HR 0.85, p=0.009)
• Major bleeding increased, but fatal/critical organ bleeding was not significantly different
• Recommended in patients without elevated bleeding risk; full-dose anticoagulation is NOT routinely recommended

Vorapaxar

• PAR-1 thrombin receptor antagonist; approved for PAD patients to reduce thrombotic CV events
• Contraindicated in prior intracranial hemorrhage

2. Lipid-Lowering Therapy

• Statins reduce mortality, MACE, MALE, and improve walking symptoms
• Pleiotropic effects: improved endothelial function, plaque stabilization, reduced platelet aggregation
• VA study (155,647 patients): high-intensity statin at PAD diagnosis significantly reduced limb loss and mortality

3. Blood Pressure Control

• Target: SBP < 140 mmHg, DBP < 90 mmHg (lower targets increasingly supported)
• ACE inhibitors are preferred:
  • Ramipril: 25% reduction in MI, stroke, and CV death vs. placebo (HOPE trial, PAD subgroup)
• ARBs are an equivalent alternative:
  • Telmisartan showed similar efficacy to ramipril with less angioedema (ONTARGET)
• Beta-blockers are NOT contraindicated in PAD

4. Glycemic Control (Diabetic Patients)

• Individualize based on age, duration of DM, comorbidities, hypoglycemia risk
• SGLT2 inhibitors (empagliflozin, dapagliflozin): reduce CV mortality, heart failure, renal events, MACE, and amputation
• GLP-1 receptor agonists (semaglutide, liraglutide): reduce CV mortality and MACE

5. Symptom Management - Intermittent Claudication

Cilostazol (Class I Recommendation - ACC/AHA)

• Dose: 100 mg twice daily for a 3-month trial
• Mechanism: Reversible PDE-IIIa inhibitor → increases cAMP → vasodilation + antiplatelet effect
• Evidence: Cochrane review of 16 RCTs - significantly improves pain-free and maximum walking distance
• Contraindication: Heart failure of ANY severity (all PDE3 inhibitors)
• Side effects: Headache (most common), palpitations, diarrhea, dizziness
• Does NOT substitute for aspirin/clopidogrel in concurrent ACS

Pentoxifylline

• No longer recommended - removed from guidelines (lack of efficacy)

6. Smoking Cessation

• Associated with decreased mortality and improved amputation-free survival
• Assess at every visit; counsel + offer pharmacotherapy + refer to cessation program
• Intensive intervention: 21.3% vs. 6.8% success at 6 months vs. minimal intervention

7. Supervised Exercise Therapy

• Most effective non-interventional treatment for claudication symptoms
• Cochrane review (32 RCTs, 1,835 patients): improved pain-free and maximum walking distance
• Meta-analysis (25 RCTs): supervised treadmill exercise improved walking by ~180 m vs. no exercise
• CMS-covered: up to 36 sessions over 12 weeks for PAD patients with walking impairment (since 2017)
• Protocol: 45-60 min, 3x/week, 12 weeks; intensity sufficient to elicit claudication symptoms
• Home-based walking: reasonable alternative if supervised therapy is inaccessible

8. Wound and Foot Care (CLTI Patients)

• Multidisciplinary approach: vascular surgeon, wound care specialists, podiatry, nutritionists
• Regular foot inspection; patient education on footwear and skin care
• Early referral for non-healing wounds

Quick Reference Summary

MACE Prevention:
  ├── SAPT: Aspirin 75-325 mg OR Clopidogrel 75 mg (preferred in smokers)
  ├── Consider: Rivaroxaban 2.5 mg BID + ASA (if low bleeding risk)
  ├── Statin: LDL goal <70 mg/dL (+ ezetimibe / PCSK9i if needed)
  └── ACE inhibitor / ARB for BP control

Limb Symptom Relief (IC):
  ├── Supervised Exercise (36 sessions / 12 wk) - most effective
  └── Cilostazol 100 mg BID (contraindicated in CHF)

Risk Factor Modification:
  ├── Smoking cessation (varenicline preferred)
  ├── Diabetes: SGLT2i or GLP-1 agonist (HbA1c <7-8%)
  └── BP target: <140/90 mmHg

• 2024 ACC/AHA PAD Guideline - PMID 38743805
• 2024 ESC Guidelines for PAD and Aortic Diseases - PMID 39210722
• 2025 SVS Focused Update - Intermittent Claudication - PMID 40316185