Understanding Critical Limb Ischemia: A Guide for Clinicians and Patients

1. Northside Cherokee 2nd Annual CV Summit Scott R. Beach, MD FACC

2. Peripheral Arterial Disease • Affects over 8 million Americans • Affects 12% of the general population and 20% of those > 70 years old • Prevalence continues to increase as baby boomer generation ages

3. Critical Limb Ischemia • Subset of PVD patients • Prevelance is 1-2% of patients with PVD over the age of 50

4. Critical Limb Ischemia • Blood flow is insufficient to meet tissue oxygen demands • Ischemic injury occurs in tissues with the least blood supply and results in necrosis • Local and systemic inflammatory response • Compensatory mechanisms: post stenotic arteriolar vasodilatation collateral circulation

5. Critical Limb Ischemia • Acute ischemia – sudden decrease is blood flow that causes a potential threat to limb viability – rest pain, ischemic ulcers, and/or gangrene who present w/i 2 weeks of event • Chronic ischemia – similar manifestations as actue ischemia but > 2 weeks.

6. Critical Limb Ischemia • Mortality approaches 25% at 1 year after diagnosis • Additional 25% require major amputation • Amputation increases morbidity and mortality – 50% mortality at 5 years • Only 65% BKA amputees ambulatory 1 yr • Only 29% AKA amputees ambulatory 1 yr

7. Rutherford Classification • Stage 0 – Asymptomatic • Stage 1 – Mild Claudication • Stage 2 – Moderate Claudication • Stage 3 – Severe Claudication • Stage 4 – Rest Pain • Stage 5 – Ischemic ulceration not exceeding the digits of the foot • Stage 6 – Severe Ischemic ulcers or gangrene

8. Pathophysiology • Usually seen when two or more levels of the distal arterial tree has a significant stenosis or occlusion. • Multi level disease promotes severe ischemia by reducing the effectiveness of collateral flow and lower distal systolic driving pressures

9. CLI treatment goals Pain Relief Heal Wounds Promote / Protect Mobility Save a LIMB Save a Life

10. Clinical Presentation of CLI • Rest Pain - Pain in foot usually when limb is elevated and relieved with dependency • Ulceration – Distal areas of extremities such as tip of toes, severe pain, dry, poor vascularity • Gangrene – Devitalized tissue

11. Clinical Presentation of CLI

12. Avoid at all Cost! BKA patient has 50% mortality at 5 years Estimated > 50% increase in energy expenditure in order to Ambulate after BKA

13. Algorithm for CLI

14. Interventional Options • Angiogram required to formulate “game plan” • Must evaluate inflow and outflow, usually multi-level disease • Treat inflow lesions first • Must optimize risk factors and anti platelet therapies

15. Equipment : Basic Needs • Sheaths • Guidewires • Crossing catheters • PTA balloons • Stents • Re-entry devices • Athrectomy devices

16. Tibial Interventions • Retrograde • Antegrade • Crossing the lesion • Pedal access • Use of CTO devices • Subintimal vs intraluminal approach

17. Anterior Tibial Artery PTA

18. Athrectomy

19. Chronic Total Occlusion

23. Anterior Tibial lesion in CLI

24. Before and After

25. Subintimal Approach

27. SFA artery CLI patient

28. Common Iliac Artery

29. Tibial artery revascularization

30. Economics of Limb Salvage • Limb salvage revascularization is expensive, but better than the alternative of primary amputation.

31. Critical Limb Ischemia • 1-year mortality for patients with CLI is 25% (mainly cardiac events) • The economic burden is high for patients with CLI • The median cost of medical care for a patient following an amputation is estimated to be twice that of a successful limb salvage

32. Goals of endovascular treatment • Increase tissue perfusion • Provide blood flow to affected area to faciliate healing • Achieve resolution of rest pain and gangrene • Improve patient function • Prevent limb loss

33. Diagnostic Testing • ABI/ PVR • Ultrasound • CTA/ MRA – good for inflow but bad for outflow • Angiogram – provides most accurate road map for developing a plan for each individual

34. Advantages of Endovascular Treatment • Minimally invasive • Avoidance of general anesthesia • Minimal risk of wound infection • Minimal recovery time • Minimal hospital stay, many going home the same day

37. Good News Goodney, JVS 2009; 50:54-60

38. Revascularization Trends Geraghty et al MVSS 2005

39. Post revascularization plan • Check distal pulses • Evaluate for possible complications of revascularization both endovascular and surgical • Patient education

40. Post Operative Period • Graft occlusion – acute rest pain may be initial presentation, or sudden motor loss/ limb weakness • Surigcal incisions – must be kept clean and dry. Observe for signs of infection (cellulitis, elevated WBC, drainage) • Lymphatic injury – clear, pale yellow drainage, lymphocele

41. Post operative • Hematoma • Pseudoaneurysm • Sphenous neuropathy – pain along the medial aspect of the lower part of the thigh and leg, usually resolves in 3-6 months

42. Foot care • Alleviate heel pressure • No bare feet! • Apply lubricating cream to legs and feet • Gangrenous lesions must be kept clean and dry • Avoid heating pads, cold packs, and any adhesives

43. Take home message • For patients who present with CLI, it is imperative to move quickly and consult an endovascular specalist • Positive outcomes require the cohesive team of endovascular specialists, podiatry, wound care, infectious disease specalists, and primary care physicians.