[Inferior vena cava compression in children with pectus excavatum]

In severe cases of pectus excavatum (PE) the sternal depression may cause distortion of the cardiac chambers and great vessels. The aim of our study was to determine if the sternal impingement causes significant inferior vena cava (IVC) compression.

Retrospective study of patients with severe PE assessed between 2015-2017. The antero-posterior (AP) and transverse diameters of the suprahepatic IVC were measured on a cardiac-MRI at the level of the diaphragmatic hiatus. Results were compared with patients that had a thoracic image study performed for other causes, adjusting for age and sex.

Among the 81 patients, 28 cases and 53 controls, 63% were males and had a mean age of 12.9±0.5 yrs. Significant differences were found between groups in both AP and transverse diameter of the IVC: 13.3±0.75 mm vs. 15.8±0.76 mm (p=0.001) and 28.8±1.34 mm vs. 27.1±0.89mm (p=0.045) respectively. After adjusting for age and sex, these differences were only statistically significant for AP IVC diameter in males 12.7±0.5 mm (95% CI 11.66-13.79 mm) vs. 16.6±0.5 mm (95% CI 15.69-17.56 mm) (p=0.000). The Pearson correlation coefficient for the Haller index was r=0.471 (p=0.01).

Male patients with severe sternal depression show changes in the IVC diameter that may correspond to compression. These changes are correlated with the severity of the deformity and can justify certain clinical symptoms and cardiac function abnormalities in patients with severe PE.