Heel Wounds Predict Mortality but Not Amputation after Infrapopliteal Revascularization

Abstract

Ischemic heel ulcerations are generally thought to carry a poor prognosis for limb salvage. We hypothesized that patients undergoing infrapopliteal revascularization for heel wounds, either bypass or endovascular intervention, would have lower wound healing rates and amputation-free survival (AFS) than patients with forefoot wounds. A retrospective chart review was performed on patients who presented between 2006 and 2013 to our institution with ischemic foot wounds and infrapopliteal arterial disease and underwent either pedal bypass or endovascular tibial artery intervention. Data were collected on patient demographics, comorbidities, wound characteristics, procedural details, and postoperative outcomes then analyzed by initial wound classification. The primary outcome was major amputation or death. Three hundred ninety-eight limbs underwent treatment for foot wounds; accurate wound data were available in 380 cases. There were 101 bypasses and 279 endovascular interventions, with mean follow-up of 24.6 and 19.9months, respectively (P=0.02). Heel wounds comprised 12.1% of the total with the remainder being forefoot wounds; there was no difference in treatment modality by wound type (P=0.94). Of 46 heel wounds, 5 (10.9%) had clinical or radiographic evidence of calcaneal osteomyelitis. Patients with heel wounds were more likely to have diabetes mellitus (DM) (P=0.03) and renal insufficiency (P=0.004). 43.1% of wounds healed within 1 year, with no difference by wound location (P=0.30). Major amputation rate at 1 year was 17.8%, with no difference by wound location (P=0.81) or treatment type (P=0.33). One- and 3-year AFS was 66.2% and 44.0% for forefoot wounds and 45.7% and 17.6% for heel wounds, respectively (P=0.001). In a multivariate analysis, heel wounds and endovascular intervention were both predictors of death; however, there was significant interaction such that endovascular intervention was associated with higher mortality in patients with forefoot wounds (hazard ratio 2.25, P<0.001) but not those with heel wounds (hazard ratio 0.67, P=0.31). Patients presenting with heel ulceration who undergo infrapopliteal revascularization are prone to higher mortality despite equivalent rates of amputation and wound healing and regardless of treatment modality. These patients may benefit from an endovascular-first strategy.