Cardiac dysfunction in acromegaly: evidence by pulsed wave tissue Doppler imaging

OBJECTIVE: To verify whether the accuracy of data on myocardial function provided by pulsed-wave tissue Doppler imaging (PWTDI), a new echocardiographic application that allows quantitative measurements of myocardial wall velocities, could help towards a better understanding of the natural history of acromegalic cardiomyopathy. DESIGN: Eighteen patients with active acromegaly (ten men and eight women; mean age 48.0+/-15.0 years) with no other detectable cause of heart disease underwent PWTDI. Thirteen healthy individuals matched for age and body mass index acted as a control group. METHODS: Ejection fraction (EF), transmitral early/late diastolic velocity (E/A) ratio and isovolumic relaxation time (IVRT) were measured by conventional echocardiography; systolic peak (Sv) and early (Ev) and late (Av) diastolic peak velocities, Ev/Av ratio and regional IVRT (IVRTs) were obtained by PWTDI. RESULTS: All patients showed appreciably abnormal left ventricular global diastolic function represented by prolongation of the IVRT (P<0.001). Using PWTDI we found a prolongation of IVRTs and inversion of the Ev/Av ratio. In addition, the Ev/Av ratio proved to be significantly negatively correlated with IVRT; this correlation was not present in the case of the E/A ratio. Furthermore, a decrease in Sv was detected in the basal segment of the lateral wall (P<0.01), which had the greatest degree of diastolic dysfunction. CONCLUSIONS: PWTDI confirmed the acknowledged diastolic dysfunction that accompanies acromegalic cardiomyopathy and highlighted the greater sensitivity of regional PWTDI with respect to global Doppler diastolic indexes. Furthermore, by revealing an impairment of regional systolic function in presence of a normal EF, the findings with PWTDI contradicted the largely accepted theory that systolic function remains normal for several years in patients affected by acromegalic cardiomyopathy.