To investigate the correlation of pan-immune-inflammation value (PIV), platelet-to-lymphocyte ratio (PLR), D-dimer (D-D) and cardiac troponin I (cTnI), as well as their combined index, with the risk stratification of acute pulmonary embolism (APE).

A total of 123 APE patients admitted to Tongxiang Hospital of Traditional Chinese Medicine (Zhejiang Province) and Punan Hospital of Pudong New Area (Shanghai) from January 2021 to October 2025 were enrolled. According to pulmonary embolism severity index (PESI) scores, patients were divided into low-risk group (39 cases) and intermediate-high-risk group (84 cases). The influencing factors of APE risk stratification were analyzed, and the predictive value of single and combined indicators for APE severity was evaluated.

The neutrophil count in the intermediate-high risk group was 5.31(3.95, 7.95)×10⁹/L, monocyte count 0.64(0.47, 0.81)×10⁹/L, PIV 565.55 (373.41, 1030.36), D-dimer 7.62(4.08, 15.18)mg/L, cTnI 20.52(8.29, 36.91)ng/ml, SII 992.30(696.69, 1 828.96), NLR 4.46(3.10, 9.44), and PLR 181.56(131.90, 281.31), which were higher than those in the low-risk group [4.46 (3.12, 5.91)×10⁹/L, 0.44 (0.35, 0.51)×10⁹/L, 171.77(127.51, 333.45), 4.31(1.54, 6.89)mg/L, 5.35(2.88, 11.94)ng/ml, 494.21 (295.97, 840.78), 2.67(1.66, 4.39), and 109.03(91.24, 144.61), respectively]; while the lymphocyte count in the intermediate-high risk group was 1.14(0.76, 1.38), lower than that in the low-risk group [1.84 (1.27, 2.12)], and the differences between groups were statistically significant (P<0.05). Multivariate binary Logistic regression analysis confirmed that high levels of PIV, PLR, D-D and cTnI were independent risk factors for intermediate-high-risk APE. Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) of PIV, PLR, D-D and cTnI for predicting intermediate-high-risk APE was 0.827 (95%CI: 0.743~0.911), 0.769(95%CI: 0.681~0.857), 0.694 (95%CI: 0.598~0.790) and 0.735 (95%CI: 0.634~0.835), respectively, while the combined index had an AUC of 0.884 (95%CI: 0.817~0.951). At the optimal cut-off value of 0.560, the sensitivity, specificity and Youden index were 89.29%, 74.26% and 0.636, respectively.

PIV, PLR, D-D and cTnI are influencing factors for the occurrence of intermediate-high risk pulmonary embolism. Elevated levels of PIV, PLR combined with D-D and cTnI are closely correlated with the risk stratification of APE. Combined detection can effectively improve the early identification ability of intermediate-high risk APE and facilitate clinical evaluation.