When constantly high levels of GH and IGF-1 stimulated the hearts of patients with acromegaly, and combined with the GH and IGF-1 receptors on the surface of cardiomyocytes, the myocardial contractility changed with increasing the intracellular calcium concentration and sensitivity to calcium, and led to myocardium interstitial collagen precipitation, muscle fiber disorder, and interstitial lymphocyte infiltration of cardiomyocytes, which eventually progressed to acromegaly cardiomyopathy (12, 35). Here, IGF1 is linked to acromegaly.