Echocardiographic Left Ventricular Systolic and Diastolic Functions in Hyperthyroidism

Abstract

In this study, left ventricular systolic and diastolic function were assessed in 24 thyrotoxic patients and 19 age-matched controls by two-dimensional and pulsed Doppler echocardiography. Enddiastolic diameter, endsystolic diameter, enddiastolic volume, endsystolic volume were measured from parasternal long axis projection. Ejection fraction, fractional shortening, stroke volume, cardiac output were calculated by those measurements. All measurements, the indexes of systolic function, were similar in both patients and controls. Peak early filling velocity (E), peak late filling velocity (A), flow velocity integral of early filling (FVIe), flow velocity integral of late filling (FVIa), deceleration time, isovolumic relaxation time (IVRT), acceleration time were measured by pulsed Doppler echocardiography and the ratio was calculated between E and A. There was no significant difference in FVIe, deceleration time, acceleration time, IVRT between the two groups. But E, E/A was significantly lower in patients groups (p < 0.01, p < 0.001, respectively). A, FVIa significantly increased (p < 0.001, p < 0.001 respectively). As a result, we found the abnormal diastolic functions in hyperthyroidism. These observations may provide an explanation for the common symptom of impaired exercise tolerance in hyperthyroidism.