Fate of the asymptomatic contralateral limb after initial intervention for ipsilateral critical limb ischemia

Aim. In Trans-Atlantic Inter-Society Concensus (TASC) patients at risk for critical limb ischemia (CLI) without symptoms are termed "chronic subclinical ische mia," but research are still lacking. The objective was to find out whether clinically asymptomatic contralateral limbs at the time of treatment for ipsilateral CLI could be regarded as "chronic subclinical ischemia". Methods. Ninety-six patients with CLI who had no symptoms in the contralateral limb were retrospectively reviewed. The symptoms of the contralateral limb after initial intervention for the ipsilateral limb were surveyed. Risk factors for developing CLI and tissue loss were then analyzed. Results. Five patients (5.2%) became claudicants, 37 patients (38.5%) had symptoms of CLI, and 14 (14.6%) experienced tissue loss during the follow-up period. The overall CLI-free rates at 12, 36, and 60 months were 79.2%, 55.2%, and 45.8%, respectively, while the tissue loss-free rates at 12, 36, and 60 months were 91.3%, 78.8%, and 78.8%, respectively. Risk factor for developing CLI on the contralateral limb was having skin perfusion pressure (SPP) <40 mmHg at the surgery for ipsilateral limb. The presence of SPP <40 mmHg and end stage renal failure with hemodialysis resulted in a significantly high probability of tissue loss. Conclusion. Patients with CLI with an asymptomatic contralateral limb with an SPP value <40 mmHg are at a high risk of developing CLI and tissue loss during the follow-up period. Information on the contralateral limb at initial surgery may help to speculate the fate of the asymptomatic contralateral limb.