Clinical Characteristics, Treatment Response, and Prognosis Between Saddle and Non-Saddle Pulmonary Embolism in Intermediate- to High-Risk Acute Pulmonary Embolism.

OBJECTIVE: To investigate the clinical characteristics of patients with saddle pulmonary embolism (SPE) among those with intermediate- to high-risk acute pulmonary embolism (APE). STUDY DESIGN: A comparative study. Place and Duration of the Study: Department of Interventional Vascular Surgery, the First Hospital of Putian City, Putian, China, from May 2017 to October 2024. METHODOLOGY: Combined anticoagulation and interventional therapy was administered to all enrolled intermediate- to high-risk APE patients (with right ventricular dysfunction and/or elevated cardiac biomarkers, or haemodynamic instability) per the study protocol. Based on whether SPE was identified on computed tomography pulmonary angiography, patients were divided into the SPE group and the non-SPE group. Clinical characteristics, cardiac biomarkers, imaging features, and clinical outcomes were compared between the two groups. RESULTS: When comparing the groups, no significant differences were observed in N-terminal pro-B-type natriuretic peptide, right ventricular diameter/left ventricular diameter, and peripheral pulmonary artery obstruction index before and after treatment (p >0.05). However, the SPE group had higher levels of cardiac troponin I than the non-SPE group before and after treatment (p <0.05). There was no significant difference in in-hospital mortality between the two groups (p = 0.653). In the SPE group, the saddle embolism resolved completely in 94.74% of patients after treatment. CONCLUSION: Patients with SPE may experience more severe myocardial injury. The short-term resolution of the saddle embolism after treatment appears not to be a critical factor affecting treatment response. KEY WORDS: Intermediate- to high-risk, Acute pulmonary embolism, Computed tomography pulmonary angiography, Saddle pulmonary embolism, Clinical characteristics.