GH and IGF-I excess causes a specific cardiomyopathy, often complicated by diastolic and systolic dysfunction until heart failure. The aim of this study is to evaluate the effects of long-term treatment with pegvisomant on cardiac performance in acromegalic patients. Twelve patients (4 men and 8 women, age 2958 years) entered the study. A radionuclide angiography at rest and during exercise was performed at baseline and after 18 months of treatment with pegvisomant with evaluation of heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure, peak filling rate (PFR), peak ejection rate (PER), PFR/PER ratio and ejection fraction (EF), both at rest (R) and during exercise (E). All patient received an initial dose of 10 mg/day of pegvisomant, then increased of 5 mg/day every 6 weeks on the basis of IGF-I levels until their normalization, or achievement of the maximal dose of 40 mg/day. At baseline, R-EF was normal in all patients whereas percent increase of EF after exercise was normal in 10 of the 12 (83.3%) patients. At the last follow-up, E-HR (130.7±17.4 vs 107.5±18.5 vs bpm, P=0.02), E-DBP (100.0±12.6 vs 86.2±4.3 mmHg, P=0.01) and E-PFR (3.98±1.42 vs 2.66±0.7 SV/s, P=0.01) were significantly reduced compared to baseline. No significant difference was found in E-SBP and E-PER. Moreover, although no significant difference was found in EF both at rest and after exercise, a significant improvement and normalization of the EF response to exercise was found in the two cases in which it was impaired at the study entry. Conversely, one patient showed a significant worsening of EF response to exercise. In conclusion, long-term treatment with pegvisomant improves cardiac performance, mainly ameliorating the response of heart rate and blood pressure to exercise.
03 - 07 May 2008
European Society of Endocrinology