The roles of the main pulmonary artery diameter, ascending aorta diameter, and their ratio in the prognosis of dyspneic patients

Objective: This study aimed to evaluate the prognostic significance of the main pulmonary artery diameter (mPAD), ascending aorta diameter (AAD), and the mPAD/AAD ratio in dyspneic patients.Method: In this retrospective study, patients aged >18 years who presented to the emergency department (ED) with dyspnea and underwent thoracic computed tomography (CT) between July 1, 2021, and December 31, 2022, were included. Demographic data, clinical outcomes, and radiological measurements were analyzed.Results: A total of 372 patients were enrolled, of whom 59 (16%) died during hospitalization. Non-survivors had significantly higher mPAD and mPAD/AAD ratios compared with survivors. Receiver operating characteristic analysis demonstrated that mPAD was the strongest predictor of in-hospital mortality, with an area under the curve of 0.72. Using a cut-off value of ≥29 mm, mPAD yielded a sensitivity of 81%, specificity of 52%, positive predictive value (PPV) of 24%, and negative predictive value (NPV) of 94%.Conclusion: The mPAD and the mPAD/AAD ratio can be used as reliable indicators of prognosis in patients presenting with dyspnea, such as predicting the need for mechanical ventilation, intensive care unit admission, and in-hospital mortality.