Does chest wall conformation influence myocardial strain parameters in infants with pectus excavatum?

Purpose To investigate the possible influence of chest wall conformation on myocardial strain parameters in a consecutive population of infants with pectus excavatum (PE), noninvasively assessed by modified Haller index (MHI). Methods Sixteen consecutive PE infants (MHI >2.5) and 44 infants with normal chest shape (MHI <= 2.5) entered in this prospective case-control study. All infants underwent evaluation by neonatologist, transthoracic echocardiography implemented with two-dimensional speckle tracking echocardiography (2D-STE) analysis of both ventricles and MHI assessment (ratio of chest transverse diameter over the distance between sternum and spine), at two time points: within 3 days and at about 40 days of life. Results At 2.1 +/- 1 days of life, compared to controls (MHI = 2.01 +/- 0.2), PE infants (MHI = 2.76 +/- 0.2) were diagnosed with significantly smaller cardiac chambers dimensions. Biventricular contractile function and hemodynamics were similar in both groups of infants. Left ventricular (LV) global longitudinal strain (GLS) (-16.0 +/- 2.8 vs. -21.7 +/- 2.2%), LV-global circumferential strain (GCS) (-16.3 +/- 2.7 vs. -24.0 +/- 5.2%), LV-global radial strain (GRS) (24.2 +/- 3.0 vs. 31.5 +/- 6.3%), and right ventricular free wall longitudinal strain (RVFWLS) (-16.0 +/- 3.2 vs. -22.3 +/- 4.4%) were significantly reduced in PE infants versus controls (all p < 0.001). A strong inverse correlation between MHI and the following parameters: LV-GLS (r = -0.92), LV-GCS (r = -0.88), LV-GRS (r = -0.87), and RVFWLS (r = -0.88), was demonstrated in PE infants, but not in controls, in perinatal period (all p < 0.001). Analogous results were obtained at 36.8 +/- 5.2 days after birth. Conclusions Abnormal chest anatomy progressively impairs myocardial strain parameters in PE infants. This impairment might reflect intraventricular dyssynchrony due to compressive phenomena rather than intrinsic myocardial dysfunction.

Automated summary

Abnormal chest wall conformation in infants with pectus excavatum may progressively impair myocardial strain parameters, possibly due to intraventricular dyssynchrony from compressive phenomena rather than intrinsic myocardial dysfunction.