Background: Vascular rings (VR) may cause severe tracheomalacia and upper airway obstruction (UAO). Increased pulmonary artery pressure and cardiac dysfunction have been described in patients with chronic UAO, but has not been investigated in infants with obstruction associated with VR. The aim of this study is to evaluate myocardial strain in infants with UAO due to VR.
Method: Demographic characteristics, respiratory symptoms, percentage of tracheal obstruction measured and classified using Computer Tomography, and lung function testing (LFT) were collected. Left (LV) and right ventricle (RV) systolic functions were measured using speckle tracking echocardiography longitudinal strain analysis (LS). Pulmonary artery pressure was evaluated using maximal tricuspid regurgitation jet velocity (TR) and LV end-systolic eccentricity index (EI).
Results: Fifteen cases were included in the study, six had mild tracheal obstruction (<50%), nine moderate-severe obstruction (≥50%). LV LS and RV LS were significantly reduced in cases with moderate to severe airway obstruction cases compared to those with mild airway obstruction (LV LS -15.9 versus -19.9%; RV LS -15.7 versus -20.5%, p = .04 and p = .02, respectively). Respiratory symptoms were more pronounced in moderate-severe cases. No significant differences in TR, EI, and LFT were observed.
Conclusions: In cases of VR with severe tracheomalacia RV and LV myocardial strain is reduced, suggesting secondary cardiac dysfunction.
Keywords: Lung function testing; myocardial strain; tracheomalacia; upper airway obstruction; vascular rings.