Japanese scoring system as a prediction of successful guidewire crossing of below-the-knee chronic total occlusion

Abstract

Background A condition known as chronic limb-threatening ischemia (CLTI) occurs when there is a drastic reduction in blood flow to the lower extremities because of arterial blockage. Aim To evaluate the efficacy of Japanese scoring system in our population as a prediction of successful guidewire crossing of below-the-knee chronic total occlusion. Patients and methods This study was conducted on 48 patients with 55 chronic total occlusion (CTO) lesions. Patient assessment included history taking, laboratory analysis, and radiological assessment of the affected limbs. Patients were prepared for intraoperative angiography and then we applied Japanese below-the-knee chronic total occlusion (J BTK-CTO) scoring in our patients with antegrade of BTK-CTO by using 0.018, 0.035 wire, or additional retrograde guidewire crossing. Results In the current study, 54.5% of the studied lesions showed technical success and 45.5% showed failure. The median J BTK-CTO score was statistically significantly higher in the cases with failed crossing as compared with the cases with successful crossing [4 (2–6) and 1 (0–4), respectively] (P < 0.001). The area under the curve for Japanese score in differentiating failure from success among the studied lesions is excellent with the best-detected cut-off point 3, yielding sensitivity of 83.3%, specificity of 96% and total accuracy 89.1%, and cut-off point 4 yielding sensitivity of 96.7%, specificity of 80% and total accuracy 89.1%. Conclusion Failure of guidewire crossing of below-the-knee chronic total occlusion is common and may be associated with serious complications. J BTK-CTO revealed high diagnostic accuracy for prediction of failure in these cases and this could provide a good prognostic score for careful management of limb ischemia. Lesions categorized as grade C or D (the J BTK-CTO score of 4–6) have a lower chance of S-GC. In such lesions, a retrograde approach using pedal artery wiring or a digital artery puncture should be considered after failure antegrade.