Determinants of Survival and Major Amputation after Peripheral Endovascular Intervention for Critical Limb Ischemia

SLR - November 2015 - Lisa Grant-McDonald

Reference: Vierthaler L, Callas PW, Goodney PP, Schanzer A, Patel VI, Cronenwett J, Bertges DJ. Determinants of Survival and Major Amputation After Peripheral Endovascular Intervention for Critical Limb Ischemia. J Vasc Surg. 2015 Sept; 62(3): 655-664.

Scientific Literature Review

Reviewed By: Lisa Grant-McDonald, DPM
Residency Program: Western Pennsylvania Hospital

Podiatric Relevance: Peripheral arterial disease afflicts approximately 8 million people per year, and represents nearly 20 percent of Americans over the age of 65. Critical limb ischemia, a class of lower limb ischemia, increases a patient’s risk for lower extremity amputation. Historically, lower extremity bypass has been the treatment of choice for correction of critical limb ischemia, however there is increasing popularity in peripheral endovascular intervention. Numerous studies have surveyed the patient survivorship, amputation rates and one year re-intervention rate in patients who have underdone peripheral bypass, however few exist to exclusively determine outcomes for peripheral endovascular procedures.  

Methods: This study is a prospective review using data from NSGNE. It followed 1414 patients who underwent peripheral endovascular interventions by 108 surgeons at 23 academic institutions. Patients included in this study had rest pain and tissue loss, but were excluded for symptoms of claudication, acute ischemia or aneurysm. Interventions were determined at the discretion of the surgeon and included balloons, stenting, and artherectomy. Arteries involved were classified in four segments for anatomic identification. Technical success was defined as residual stenosis less than 30 precent. Outcome measures were one-year overall survival, freedom from amputation, morbidity and intervention rate.

Results: One thousand fourteen interventions were performed on 1253 patients. Patient co-morbidities were hypertension (90 percent), smoking (75 percent), diabetes (61 percent), and renal insufficiency (8 percent). Overall survival was deemed lower for patients treated for rest pain. Survival rates were lower in patients with tissue loss, emergency procedures, dialysis, age >80, CHF, dependent living status prior to intervention, creatinine > 1.8. Several predictors were associated with major amputation, which included dialysis, tissue loss, prior amputation, non-Caucasian race, and male gender. Interestingly smoking appeared to protect from future amputation.

Conclusions: The recent insurgency of endovascular procedures is in part due to the limited morbidity and mortality inherent to the procedure however re-intervention and durability remain an important consideration with these procedures. It has become a great challenge for the vascular surgeon to weigh the risk of co-morbidities and potential for functional improvement in patients. This study is helpful as it recognizes the increased failure risk for patient with several co-morbidities. The greatest predictor of failure of endovascular procedure is dialysis dependence. The data from this study only begins to aid in risk-adjusted outcome reporting and patient selection criteria.