Pediatric Myocardial T1 and T2 Value Associations with Age and Heart Rate at 1.5 T.

ABSTRACT

The objective of the study was to determine normal global left ventricular reference values for T1 and T2 in children. This is a retrospective study that included healthy subjects, age 5-19 years, who underwent CMR for the indication of pectus excavatum from 2018 to 2019. Linear regression models were used to determine associations of native T1 and T2 values to heart rate, age, and other CMR parameters. 102 patients with a mean age of 14.0 ± 2.4 years were included (range 5.4-18.8). 87 (85%) were males and 15 (15%) were females. The mean global T1 was 1018 ± 25 ms and the mean T2 was 53 ± 3 ms. T1 was negatively correlated with age (r = - 0.39, p < 0.001) and positively correlated with heart rate (r = 0.32, p < 0.001) by univariate analysis. Multivariable analysis showed that age and heart rate were independently associated with T1. T2 demonstrated a weak negative correlation with age (r = - 0.20, p = 0.047) and no correlation with heart rate. There was no difference in T1 (p = 0.23) or T2 (p = 0.52) between genders. This study reports normal pediatric T1 and T2 values at a 1.5 Tesla scanner. T1 was dependent on age and heart rate, while T2 was less dependent on age with no correlation with heart rate.