WIfI Classification Based Analysis of Risk Factors for Outcomes in Patients with Chronic Limb Threatening Ischaemia after Endovascular Revascularisation Therapy

Abstract

Evaluating limb status with WIfI classifications and assessing patient risks combined with systemic factors were recommended in patients with chronic limb-threatening ischemic (CLTI). However, there was little application evidence of WIfI in the Chinese population. This study aimed to verify the utilization of the WIfI classification in a China patient population, and further identify local and systemic independent predictors for adverse outcomes of CLTI. A total of 474 patients who underwent endovascular therapy (EVT) for CLTI in a tertiary hospital between July 2017 and September 2020 were included in this retrospective study. The outcomes included 1-year major adverse limb events (MALEs), 1-year all-cause mortality, and 1-year amputation-free survival (AFS). Cox regression was used to analyze the association between risk factors and adverse outcomes. There were 104 (21.9%) all-cause mortalities observed. The MALEs rate was 17.5%, while AFS rate was 71.9%. The multivariate analysis revealed that a BMI < 18.5 kg/㎡ (P = .002), a left ventricular ejection fraction (LVEF) < 50 % (P < .001), and WIfI-Wound Grade (P < .001) were independent risk factors for MALEs, while age ≥ 77 years (P = .031), a BMI < 18.5 kg/㎡ (P < .001), coronary heart disease (P = .040), and WIfI clinical stages (P = .021) were independent risk factors for mortality in CLTI patients. Besides, age ≥ 77 years (P = .003), a BMI < 18.5 kg/㎡ (P < .001), coronary heart disease (P = .012), a LVEF < 50 % (P < .001), WIfI-Wound Grade (P = .004) and WIfI clinical stages (P = .044) were independently associated with a decreased AFS rate. This study confirms the predictive ability of WIfI classification for Chinese CLTI patients who underwent EVT. Wound grade was the most sensitive and important risk factor among the three components of WIfI. In addition, systemic factors should also be considered to ensure a more accurate prognosis prediction and appropriate clinical decision-making in CLTI patients.