Features of asymptomatic contralateral limb in patients with chronic limb-threatening ischemia

•We analyzed asymptomatic contralateral limbs of chronic limb-threatening ischemia.•Around half of the limbs were exposed to severe ischemia.•They had a high risk of major adverse limb events as well as mortality. The current study aimed to reveal clinical features and prognosis of asymptomatic contralateral limbs in patients undergoing revascularization for chronic limb-threatening ischemia (CLTI). We analyzed a database of 520 CLTI patients registered in a prospective, multicenter registry in Japan. Severe ischemia in asymptomatic contralateral limbs was determined as the Wound, Ischemia, and foot Infection (WIfI) classification system Ischemia (I) grade 2/3. The prevalence of diabetes mellitus and dialysis-dependent renal failure was 74.2% and 53.5%, respectively. Asymptomatic limbs accounted for 65.0% [95% confidence interval (CI), 60.9–69.1%] of the overall population, and 55.0% (95% CI, 49.6–60.4%) of the asymptomatic contralateral limbs had WIfI I-2/3. The multivariate analysis identified age ≥65 years, dialysis-dependent renal failure, WIfI I-3 in the index limb, and loss of pressure sensation in the contralateral limb as independent risk factors for WIfI I-2/3 in asymptomatic contralateral limbs (all p