Improvement of left ventricular hypertrophy and arrhythmias after lanreotide-induced GH and IGF-I decrease in acromegaly. A prospective multi-center study

We report the results of a prospective Italian multi-center study of the effects of lanreotide, a slow-release somatostatin analog, on left ventricular morphology and function and on the prevalence of ventricular arrhythmic events in 19 patients with active, newly diagnosed, uncomplicated acromegaly. Cardiac features were evaluated with Doppler-echocardiography and 24-h Holter ECG monitoring at baseline and after 6 months of lanreotide therapy. Fifteen patients (78.9%) had left ventricular hypertrophy. Lanreotide treatment significantly decreased the left ventricular mass (127.8±6.9 vs 140.7±7.1 g/m², p<0.001) and left ventricular hypertrophy significantly disappeared in 6 of these patients. Treatment did not significantly affect systolic function, whereas it increased the Doppler-derived early-to-late mitral flow velocity, (E/A) ratio, of early-to-late transmitral flow velocity (1.34±0.1 vs 1.09±0.06, p=0.001). Stroke volume was slightly but not significantly increased after treatment, whereas systolic BP was significantly higher (134±14 vs 129±13 mmHg, p<0.05). The 24-h mean heart rate was significantly reduced after treatment (66.5±11 vs 71.5±20 beats/min, p<0.05). Supra-ventricular premature beats (>50/24 h) occurred in 16.6% of patients and were unaffected by treatment. Differently, ventricular premature beats (>50/24 h) occurred in 33.3% of patients before treatment vs 16.5%, after treatment. In conclusion, lanreotide reduced the left ventricular mass, and improved ventricular filling and ventricular arrhythmic profile.