Echocardiographic evidence for a direct effect of GH/IGF-I hypersecretion on cardiac mass and function in young acromegalics

Clin Endocrinol (Oxf). 1998 Jul;49(1):101-6. doi: 10.1046/j.1365-2265.1998.00493.x.

Abstract

Objective: The interpretation of echocardiographic abnormalities in acromegalic patients is complicated by non-specific age-related diseases, many of which are commoner in acromegaly. We have therefore investigated the cause-effect relationship between GH/IGF-I hypersecretion and precocious cardiovascular abnormalities in a series of young acromegalic patients.

Design: An open prospective study.

Patients: 20 acromegalic patients aged under 30 years, with normal blood pressure and glucose tolerance, and 20 age-matched control subjects.

Measurements: Cardiac morphological parameters and indices of systolic and diastolic function at rest were studied by Doppler echocardiography.

Results: Left ventricular mass (LVM) and LVM index (LVMi) were higher in acromegalics than in control subjects (215.0 +/- 15.4 g vs 140.8 +/- 8.5 g, P = 0.0002 and 109.8 +/- 5.9 g/m2 vs 82.1 +/- 3.7 g/m2, P = 0.0008, respectively), reaching values of left ventricular hypertrophy in 4 patients (20%). Both ejection fraction and fractional shortening were normal (66.4 +/- 2.1% vs 62.2 +/- 1.9% and 37.5 +/- 1.5% vs 35.8 +/- 1.3%, respectively), indicating normal left ventricular systolic function. Abnormalities of left and right diastolic ventricular filling were found, which consisted of an increased isovolumic relaxation time (99.2 +/- 2.7 ms vs 89.0 +/- 2.7 ms, P = 0.01) and impaired mitral and tricuspidal flow velocity curves.

Conclusions: An increase in cardiac mass and subclinical biventricular diastolic dysfunction were observed in young acromegalic patients. These findings argue for a direct cause-effect relationship between GH/IGF-I hypersecretion and myocardial abnormalities, and indicate that careful cardiological evaluation is mandatory in all acromegalics, whatever their age.

MeSH terms

  • Acromegaly / diagnostic imaging
  • Acromegaly / physiopathology*
  • Adult
  • Case-Control Studies
  • Diastole
  • Echocardiography, Doppler*
  • Female
  • Growth Hormone / metabolism*
  • Heart / physiopathology
  • Humans
  • Insulin-Like Growth Factor I / metabolism*
  • Male
  • Prospective Studies
  • Regression Analysis
  • Statistics, Nonparametric

Substances

  • Insulin-Like Growth Factor I
  • Growth Hormone