Development and validation of a nomogram for predicting restenosis in 12 months after percutaneous transluminal angioplasty of arteriosclerosis obliterans

Abstract

Objective To develop and validate an individualized prediction model for risk of restenosis in patients with arteriosclerosis obliterans (ASO) after percutaneous transluminal angioplasty (PTA). Methods A case-control trial was conducted on 137 patients who received PTA treatment for ASO in the Department of Vascular Surgery of the First Affiliated Hospital of Chongqing Medical University from February 2020 to May 2022. Their clinical data were collected and analyzed. The patients were assigned into training set (n=97) and validation set (n=40) at a ratio of 7 ∶3. The primary endpoint was the occurrence of restenosis within 12 months after interventional procedure. Based on the training set, single and multiple factor Cox regression models were used to screen the independent influencing factors of restenosis within 12 months. Then the obtained regression coefficients were then employed to establish a prediction model and draw a nomogram. The data from the training and validation sets were adopted to validate the model internally and externally, and the area under the receiver operating characteristic curve (AUC) and calibration chart were used to evaluate the model's recognition. The decision curve chart was established to evaluate the benefit of using the model to treat patients. Results Intravascular ultrasound guidance, lesion type, preoperative residual outflow tract, lesion length, and intraoperative treatment were independent predictors of restenosis after PTA in ASO patients (P < 0.05) and included in the model. The AUC of the nomograph for model's internal validation was 0.84 (95%CI: 0.75~0.92), with a specificity and sensitivity of 0.797 and 0.737, respectively. The AUC of the external validation using the validation set was 0.86 (95%CI: 0.74~0.98), with a specificity and sensitivity of 0.963 and 0.615, respectively. The calibration curve in the 2 cohort groups showed that the predictive value of the nomogram matched the actual observation. The decision curve indicated that this model could significantly increase the net benefit to patients. Conclusion Our nomogram prediction model can predict vessel patency of ASO patient within 12 months after PTA, and it has been developed and validated as an individualized risk prediction model for this specific group.

Keywords

• arteriosclerosis obliterans
• angioplasty
• recurrence
• prediction model
• nomogram