Sleep Apnea and Cardiovascular Complications of the Acromegaly. Response to the Medical Treatment

Acromegaly is a rare disease characterized by high levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). The excess of GH leads to the development of different manifestations in different organs, from subtle signs in the bones and soft tissues to the development of respiratory and cardiac insufficiency. In the cardiovascular system, the GH/IGF-1 axis exerts its influence on three major aspects: myocyte growth and structure, cardiac contractility and vascular function. In this article, we review the different cardiovascular and respiratory complications as well as the effects of the different treatments on these complications. Cardiovascular complications that occur in acromegaly are known as "acromegalic cardiomyopathy," and include ventricular hypertrophy, impaired diastolic and systolic function, valve diseases, coronary artery disease, and arrhythmias. Acromegaly is also associated with relevant complications of the respiratory system, mainly sleep apnea and respiratory insufficiency. Regarding treatment, there are different therapeutic strategies. Surgery is the first-choice treatment, but in general, half of patients will require adjuvant treatments, such as medical treatment (somatostatin analogues, dopamine agonists and GH receptor antagonists) or radiotherapy. The treatment can improve some complications of acromegaly, such as left ventricular hypertrophy, hypertension, or obstructive sleep apnea. On the other hand, when strict control of the disease is achieved, a reduction in mortality and cardiovascular morbidity is assured, reaching rates similar to those of the general population.