Sternal torsion in pectus excavatum is related to cardiac compression and chest malformation indexes

Abstract

Background/purpose: The role of sternal torsion (ST) in patients with pectus excavatum (PEX) is unknown. We evaluated the relationship between ST and both chest malformation and cardiac compression (CC) indexes. Methods: We included consecutive patients with PEX who underwent chest computed tomography and cardiac magnetic resonance (CMR) to define surgical candidacy. Malformation indexes included the Haller index (HI), correction index (CI), and ST. CC and the tricuspid to mitral annulus width ratio were evaluated using CMR. Results: One-hundred and sixteen patients were included, with a mean HI of 5.8 ± 3.6 and a mean CI of 35.8 ± 18.0%. ST was significantly related to malformation indexes, being patients with absence of ST those showing the lowest HI (p = 0.048) and CI (p = 0.002). Right-sided ST was significantly related to the CC classification (p = 0.0001), and the tricuspid/mitral annulus width ratio was significantly lower among these patients (absence 0.98 ± 0.15, left-sided 0.91 ± 0.10, right-sided 0.80 ± 0.15, p < 0.0001). A significant inverse relationship between ST degrees and the tricuspid/mitral ratio was also identified (r = -0.47, p < 0.0001). Conclusions: We identified a significant relationship between ST and both chest malformation and CC indexes; the absence of ST being identified as a marker of an overall more benign phenotype.