A 62-year-old man with a 40-year history of smoking presents with a 3-month history of progressive pain in the left calf that worsens with walking 100 metres and improves with rest. On examination, the left foot is cool to touch, and the dorsalis pedis and posterior tibial pulses are absent on the left side. The right-sided pulses are normal. Ankle-brachial index (ABI) on the left is 0.58. What is the most appropriate next step in management?

Explanation

## Clinical Presentation & Diagnosis This patient has **intermittent claudication** (Fontaine Stage II peripheral arterial disease): - Progressive calf pain on exertion (100 m claudication distance) - Relief with rest - Absent pedal pulses - **ABI 0.58** confirms haemodynamically significant stenosis (normal >0.9; claudication 0.5–0.9; critical limb ischaemia <0.4) ## Management Algorithm for Claudication ```mermaid flowchart TD A[Intermittent Claudication<br/>ABI 0.5-0.9]:::outcome --> B{Lifestyle limiting?}:::decision B -->|No| C[Conservative: Exercise,<br/>Smoking cessation, Statins]:::action B -->|Yes| D[Duplex ultrasound<br/>to assess anatomy]:::action D --> E{Suitable for<br/>intervention?}:::decision E -->|Yes| F[PTA or Surgery]:::action E -->|No| C C --> G[Reassess at 3-6 months]:::action ``` ## Key Point: **Claudication is managed conservatively first** unless symptoms are lifestyle-limiting or rapidly progressive. This patient has stable claudication with a walking distance of 100 m. ## High-Yield Management Steps | Intervention | Indication | Timing | |---|---|---| | **Conservative therapy** | All claudicants; first-line | Immediate | | **Duplex ultrasound** | Diagnosis confirmation; anatomical assessment before intervention | If intervention planned | | **Revascularization (PTA/surgery)** | Lifestyle-limiting claudication; critical limb ischaemia; rest pain | After failed conservative therapy or acute deterioration | ## Conservative Therapy Components 1. **Antiplatelet agent**: Aspirin 75 mg daily (or clopidogrel if aspirin intolerant) 2. **Statin**: High-intensity (atorvastatin 80 mg) — reduces cardiovascular events by ~25% in PAD 3. **Supervised exercise programme**: 30–50 min, 3×/week for 12 weeks — improves claudication distance by 50–100% 4. **Smoking cessation**: Halts disease progression; critical 5. **Blood pressure control**: Target <140/90 mmHg 6. **Glycaemic control**: If diabetic **Clinical Pearl:** Most claudicants (70–80%) remain stable or improve with conservative therapy alone. Revascularization is reserved for failure of conservative management or critical limb ischaemia. **Warning:** Do not rush to imaging or intervention in stable claudication — this increases cost and risk without proven benefit. Duplex is reserved for patients who fail conservative therapy or have critical limb ischaemia. [cite:Bailey & Love 27e Ch 55]