Cardiac function in primary hypothyroidism
J. T. Hayford, R. M. Schieken and R. G. Thompson
Cardiac chamber dimensions and myocardial function were studied in 15
children with primary hypothyroidism prior to and after thyroxine therapy.
Small pericardial effusions were detected in 11 of 15 subjects before
therapy, which resolved in nine of 11 subjects after initiation of
thyroxine replacement. There was no association between the severity of the
thyroid failure and the presence of effusion, and no evidence of cardiac
compromise due to effusions. No significant abnormality in cardiac chamber
or myocardial dimensions, systolic time intervals, or indices of myocardial
contractility was detected among the hypothyroid children as compared with
a normal population. Neither myocardial dimensions nor contractility
indices changed significantly on reestablishment of normal thyroxine
concentrations with exogenous hormone. These data refute the existence of a
myocardiopathy associated with hypothyroidism in children.