Endocrine Abstracts

Background: Acromegaly affects almost all organs, including the cardiovascular system. Long-term exposure to high levels of IGH and insulin-like-growth-factor 1 (IGF1) may lead to cardiomyopathy.

Study design: Aim of our investigation was to study cardiac function in patients with active acromegaly using magnetic resonance imaging of the heart (cardiac-MRI) and echocardiography. Eleven patients with active acromegaly could be evaluated within a period of 6 months.

Results: Mean age of the patients (six woman, five men) was 51.5 years (range 23–78). As IGF1 levels have age-related normal ranges, Z-scores were used to compare the endocrine tumor activity. Mean IGF1 value was 416.2 ng/ml ± 228.9 with a mean Z-score for all patients with 2.7.

Echocardiographic evaluation revealed a hypertrophic left ventricle in five patients (45.5%) with an enlarged left atrium in six patients (54.5%). Interventicular septal thickness was enlarged in seven acromegalic patients (63.6%). Mean septal thickness was 12.5 mm (24)±2.3 in men and 12.3 mm±3.0 in women. Diastolic dysfunction measured by early (E) to late (A) atrial peak velocities (E/A ratio) could be seen in three patients (27.8%). Systolic left ventricular ejection fraction (LVEF) was within the low normal range (mean 57.2%±3.6) in all but one patient.

Cardiac MRI confirmed left ventricular hypertrophy in five patients. In four patients (36.4%) a late enhancement could be found in MRI imaging as a sign of myocardial fibrosis. Intramyocardial oedema coud nor be detected. All but one patient with pathologic findings in cardio-MRI or in echocardiography had Z-scores for IGF1 levels above 2.2.

Conclusion: Cardio-MRI gives additional information to standard echocardiographic examinations in the cardiovascular work-up of patients with acromegaly. For the first time cardiac fibrosis could be detected in a relevant proportion of patients with acromegaly by MRI.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.