Chronic treatment with the somatostatin analog octreotide improves cardiac abnormalities in acromegaly

The aim of this study was to investigate the effects of a 6-month octreotide treatment on cardiac mass and function by means of Doppler echocardiography in 11 normotensive patients affected with active acromegaly. The GH and insulin-like growth factor-I levels were normalized during octreotide therapy from 34 ± 6.5 and 767.4 ± 72.4 μg/ L to 4.6 ± 0.9 and 235 ± 10.3 μg/L, respectively (P <0.001; mean ± SEM). After the 6-month treatment, we observed a significant decrease in the left ventricular mass index from 138 ± 11 to 116 ± 13 g/m² (P <0.001) and in the mean wall thickness/internal end-diastolic radius ratio from 0.47 ± 0.1 to 0.44 ± 0.1 (P <0.001). No significant differences were found in systolic function indices, whereas diastolic filling indices improved over the course of the therapy; the isovolumic relaxation time decreased from 115 ± 6 to 100 ± 6 ms (P<0.05), tricuspid late diastolic filling velocities decreased from 41 ± 3 to 36 ± 2 cm/s (P <0.03), and tricuspid deceleration time decreased from 280 ± 28 to 198 ± 15 ms (P <0.005); the ratio of early to late peak velocity of the right ventricular filling significantly increased from 1 ± 0.01 to 1.3 ± 0.1 (P <0.03). A significant correlation was detected between left ventricular mass regression and increase in the early to late peak velocity ratio of the left ventricular filling (r = 0.62; P <0.05). The results of this study show an improvement in cardiac structural and functional abnormalities during chronic treatment with octreotide, thus supporting the hypothesis of a specific heart disease secondary to high circulating GH levels.