Risk Factor Analysis for Crossing Failure in Primary Antegrade Wire-Catheter Approach for Femoropopliteal Chronic Total Occlusions

Introduction: Antegrade wire-catheter crossing remains the primary approach for femoropopliteal interventions. Nonetheless, data reporting on crossing failure are limited. Aim of this study is to identify risk factors for antegrade crossing failure in patients with femoropopliteal chronic total occlusions (CTOs). Methods: This is a single-center, retrospective analysis. Patients with femoropopliteal CTOs treated between May 2018 and February 2020 were included into this study. Primary endpoint of this analysis was primary crossing success defined as successful antegrade crossing without the use of retrograde access, crossing or re-entry devices. The assisted crossing success was additionally analyzed. A logistic regression analysis identified risk factors for failed primary antegrade crossing. Results: Data from 300 patients were analyzed. The majority (n=183, 61%) presented with lifestyle limiting claudication. The mean lesion length was 180 mm [interquartile range (IQR) 100-260 mm], whereas the median CTO length was 100 mm (IQR=50-210 mm). A chronic total occlusion crossing approach based on plaque morphology (CTOP) type I configuration was observed in 9% (n=26) of the lesions, type II in 61% (n=183), type III in 8% (n=25), and type IV in 66 CTOs (n= 66, 22%). Severe calcification based on the Peripheral Arterial Calcium Scoring Scale (PACSS), Peripheral Academic Research Consortium (PARC), and 360 degrees grading systems was identified in 17%, 24%, and 28% of the lesions, respectively. A contralateral femoral access was used in 278 cases (93%). The primary crossing success amounted to 70% (n=210). The use of a re-entry device in 28 patients (9%) or of a combined antegrade-retrograde approach in 11% (n=34) of the cases increased the assisted crossing success to 89% (n=267). The presence of calcification (odds ratio [OR]=4.2, 95% CI=1.7-10.2) or of circumferential calcium (OR=2.5, 95% CI=1.3-4.9), a CTOP class Iota Iota Iota or Iota V (OR=1.9, 95% CI=1.4-2.6), a proximal superficial femoral artery (SFA) occlusion (OR=3.5, 95% CI=1.7-7.4) and a CTO at P3 (OR=4.1, 95% CI=1.5-10.8) were associated with an increased risk for antegrade crossing failure. Conclusions: In this study, chronic total occlusions (CTO) morphology, calcification burden, and lesion's location were identified as independent risk factors for failed antegrade crossing. Nonetheless, the use of alternative crossing strategies significantly increased the overall crossing success.