Background: Multiple studies have reported physiologic cardiac remodeling among collegiate-level athletes, however, there is marked variation in reported left ventricular (LV) remodelling parameters. This study sought to explain the heterogeneity in echocardiographic derived LV mass.
Methods: Pre participation screening was performed in National Collegiate Athletic football players between 2008 and 2016. Demographics were obtained at the time of image acquisition. Echocardiographic measures were completed per current guidelines with LV mass calculated by the area length method and compared to 28 age matched sedentary controls. Inter ventricular septal diameter (IVSd) was assessed with and without inclusion of the septal band (Figure 1). Conservation of mass was used as a quality metric, ensuring <5% difference in mass between diastole and systole.
Results: 230 players were screened, mean age 18.5 ± 1.2 years and body mass index (BMI) 29±4 kg/m2. LV ejection fraction and global longitudinal strain were lower in players than controls (59 ± 4% vs 62 ± 4%, p<0.001; -19.0 ± 2.0% -19.8 ± 1.2%, p=0.021). LV mass was higher in players (79 ± 10kg/m2 vs 65 ± 16 kg/m2, p<0.001). In a multivariate model with LV mass as the dependent variable and race, position, BMI and BP as independent variables only BMI was significant (r partial 0.61, p<0.001). On assessment of the IVSd, the septal band was identifiable in 194 players (84.3%) on parasternal short axis imaging. The band inserted into the mid anterior septum in 175 (90.2%) of cases. IVSd measured with inclusion of the septal band was higher than without (12.0 ± 1.4mm vs 8.4 ± 1.1mm, p<0.001), translating into a 27% different in LV mass.
Conclusion: Among collegiate football players, body composition appears to be the strongest contributor to variation in LV remodelling parameters and in assessing septal wall thickness the inclusion or exclusion of the septal band may partially explain the significant variability seen in reported LV mass.