The AS-PAD Score: A Novel Risk Stratification Tool for Predicting Peripheral Artery Disease and Vascular Complications in Severe Aortic Stenosis Patients Undergoing TAVI

U. A. Gohman (Bochum)¹, M. A. Nashtar (Bochum)¹, P. Liedtke (Bochum)², O. Azizy (Bochum)³, J. Trippe (Bochum)⁴, J. Strauch (Bochum)⁵, A. Canbay (Bochum)⁶, I. Schmitz (Bochum )⁷, M. Steinmetz (Bochum)⁴, P. C. Patsalis (Bochum)^1
1Knappschaft Kliniken Universitätsklinikum Bochum Medizinsche Klinik; Kardiologie, Angiologie und Internistische Notfallmedizin Bochum, Deutschland; ²Ruhr-Universität Bochum Medizinische Fakultät, Molekulare Immunologie Bochum, Deutschland; ³Knappschaftskrankenhaus Bochum-Langendreer Medizinische Klinik Bochum, Deutschland; ⁴Universitätsklinikum Knappschaftskrankenhaus Bochum Kardiologie, Angiologie und internistische Notfallmedizin Bochum, Deutschland; ⁵Berufsgenossenschaftlliches Universitätsklinikum Bergmannsheil gGmbH Herz- und Thoraxchirurgie Bochum, Deutschland; ⁶Knappschaft Kliniken Universitätsklinikum Bochum Medizinsche Klinik Bochum, Deutschland; ⁷Ruhr-Universität Bochum Medizinische Fakultät, Molekulare Immunologie Bochum , Deutschland

Background:
Severe aortic stenosis (AS) is frequently accompanied by peripheral artery disease (PAD), which complicates the management of these patients and increases procedural risks. The coexistence of AS and PAD significantly raises morbidity and mortality, highlighting the need for early detection and individualized treatment strategies.

Objective:
This study aims to develop a reliable risk score, the Aortic Stenosis with Peripheral Artery Disease (AS-PAD) Score, to predict significant PAD and related vascular complications in patients with severe AS undergoing transcatheter aortic valve implantation (TAVI), thereby improving periprocedural management.

Methods:
A retrospective analysis was conducted on 138 patients with severe AS (124 undergoing TAVI). Univariate and multivariate logistic regression analyses were performed to identify key predictors of significant PAD (≥50% stenosis). The AS-PAD Score was derived by assigning points based on significant factors: 2 points for age >75 years, 3 points for diabetes, -1 point for BMI >25 kg/m² (protective effect), and 1 point for elevated Lp(a) levels. Additionally, the Fontaine stage was included, assigning points as follows: stage I (asymptomatic) = 0, stage IIa (claudication >200 m) = 1, stage IIb (claudication <200 m) = 2, stage III (rest pain) = 3, and stage IV (necrosis/gangrene) = 4 points. The total score (maximum 10 points) classifies patients into low (-1–2), intermediate (3–6), and high risk (7–10). Internal validation of the model was performed using ROC analysis, bootstrap resampling, and 5-fold cross-validation. Vascular complications were assessed according to VARC-3 criteria.

Results:
The final model demonstrated good predictive performance, with an AUC of 0.804. Multivariate logistic regression identified age >75 years (OR 2.32, 95% CI: 1.36–7.82; p = 0.044) and diabetes (OR 3.71, 95% CI: 1.33–10.7; p = 0.013) as significant risk factors, while BMI >25 kg/m² was found to be protective (OR 0.26, 95% CI: 0.09–0.74; p = 0.011). Elevated Lp(a) was independently associated with PAD (OR 1.006, 95% CI: 1.00–1.029; p = 0.042). The AS-PAD Score demonstrated robust internal validation, with a Youden Index-based cutoff of >3.5, and consistent performance in bootstrap and k-fold analyses. Minor vascular complications were significantly more frequent in patients with intermediate- or high-risk scores (44% vs. 0%, p < 0.001), but interventional management was successful in all cases with additional closure techniques. No major vascular complications were observed.

Conclusions:
The AS-PAD Score effectively predicts significant PAD and related access site vascular complications in patients with severe AS undergoing TAVI. This tool can aid in risk stratification and optimize peri-interventional management, particularly for high-risk individuals.