Iliac Calcium Score thresholds predict cardiovascular and limb-related outcomes in TASC D aortoiliac disease

Introduction Extensive lower limb arterial calcification complicates revascularization and is linked to poor outcomes, including limb loss and cardiovascular events. Standardized scoring systems are lacking, particularly in aortoiliac TASC II D lesions. This study evaluated the prognostic value of a CT-based Iliac Calcium Score (ICS) in predicting major adverse limb events (MALE), cardiovascular events (MACE), and all-cause mortality in patients with severe aortoiliac disease. Methods In this prospective cohort (2013–2024), 109 patients with TASC II D aortoiliac occlusive disease underwent elective revascularization and preoperative CT angiography. Iliac artery calcification was scored semiquantitatively by morphology, circumference, and lesion length. Patients were stratified into low (≤ 36) and high (≥ 37) ICS groups. Outcomes included MALE, MACE, and mortality, analyzed using Kaplan-Meier and Cox regression. Results The study included 109 patients (95.4% male) with a median follow-up of 67 months. Baseline characteristics were similar across ICS groups, though ICS ≥ 37 was associated with more advanced Rutherford stages ( p = 0.035). At 30 days, both groups improved clinically, but Rutherford class improvement was greater in the ICS ≤ 36 group ( p = 0.013), with no other significant differences. At 1 year, MALE was more frequent in patients with ICS ≥ 37 (48.1% vs. 27.3%; p = 0.024). At 60 months, this group showed significantly lower amputation-free (74.5% vs. 97.8%; p = 0.002), MACE-free (47.3% vs. 73.4%; p = 0.005), and overall survival (54.6% vs. 77.0%; p = 0.013). Acute heart failure occurred only in the high ICS group ( p = 0.015), while patency rates were similar. ICS ≥ 37 remained an independent predictor of MACE (aHR 2.30; p = 0.008) and major amputation (aHR 7.52; p = 0.008) in multivariable analysis. Conclusion In patients with extensive TASC II D aortoiliac occlusive disease, an ICS ≥ 37 was independently associated with increased long-term risk of MACE, MALE, and reduced overall survival, despite similar short-term outcomes. These findings support the integration of preoperative calcium scoring as a simple, lesion-specific tool for risk stratification, procedural planning, and personalized postoperative surveillance in complex peripheral arterial disease.