Decreased size of the left anterior descending coronary artery is an independent predictor of deterioration in non-high-risk patients with acute pulmonary embolism.

To evaluate the efficacy of measuring left coronary artery size to predict deterioration in non-high-risk acute pulmonary embolism (PE) patients. This retrospective study enrolled non-high-risk acute PE patients from January 2011 to December 2019. Patient deterioration was defined as the occurrence of adverse events within 30 days of hospital admission. Patients with adverse events were sex- and age-matched to patients without adverse events. Risk stratification was performed. Cross-sectional areas (CSAs) of the left main and left anterior descending (LAD) coronary artery inlets were measured. The main pulmonary artery (MPA) inlet and outlet and MPA LAD plane, which adjoined the LAD in the MPA, were reconstructed. CSAs, perimeters, and hydraulic diameters were measured to evaluate MPA size and deformation. Cardiac volume was also measured. Quantitative parameters were divided into tertiles. After adjustment by risk stratification, univariate and multivariate analyses were performed. Correlations between different parameters were analysed. Seventy-three patients with adverse events were matched to 73 patients without adverse events. The results of the univariate and multivariate analyses revealed that LAD inlet CSAs (middle and high) predicted adverse events (odds ratio: 0.28 and 0.07, 95% confidence interval: 0.10-0.77 and 0.02-0.22, p = 0.013 and < 0.0001). LAD inlet CSA was strongly and negatively correlated with MPA LAD hydraulic diameter and CSA (correlation coefficients: - 0.643 and - 0.604, p < 0.001). LAD inlet CSA measurement would facilitate adverse event prediction in non-high-risk acute PE patients on the basis of risk stratification. The dilated MPA may involve the decrease in LAD inlet CSA.