THU059 Increased Intracellular And Extracellular Myocardial Masses On Cardiac Magnetic Resonance Imaging In Patents With Acromegaly

Abstract Disclosure: P. Wolf: None. K. Bouazizi: None. N. Kachenoura: None. C. Piedvache: None. A. Gallo: None. S. Salenave: None. L. Maione: None. J. Young: None. M. Prigent: None. A. Lecoq: None. E. Kuhn: None. H. Agostini: None. S. Trabado: None. A. Redheuil: None. P. Chanson: Research Investigator; Self; Pfizer. P. Kamenicky: None. Background: Acromegaly is associated with an increased left ventricular mass, as reported in echo-based and more recently in few cardiac MRI studies. One possible explanation of this increased ventricular mass could be water retention and consequently edema of the ventricular wall. Methods: In this prospective, cross-sectional study 26 patients with active acromegaly and 31 control subjects of comparable age and sex were investigated by cardiac MRI. Patients were explored before and after GH/IGF-I lowering treatment. Cardiac morphology, function and myocardial tissue characteristics were assessed. T2 times were used as a reflect of intramyocardial water content. Results: Ventricular mass (58.08 (54.71; 68.6) vs 46.02 (41.27; 49.82) g/m2; p<0.001) and volume (97.25 (88; 101.21) vs 81.64 (78.08; 96.23) mL/m2; p= 0.0069) were higher in patients compared to controls, without affecting cardiac function. T2 times were not increased in active acromegaly. Both, intracellular (87.9 (71.2; 103.6) vs 67.2 (51.6; 76.9) g/m2; p<0.001) and extracellular (31.9 (26.1; 36.6) vs 21.8 (19.2;24.7) g/m2; p<0.001) myocardial mass were higher in patients compared to controls. GH, but not IGF-I strongly correlated with myocardial mass (r=0.756; p<0.001). In multiple regression analysis, in addition to male sex and HDL cholesterol, the presence of acromegaly was an independent predictor of total myocardial mass and extracellular mass, whereas systolic arterial blood pressure predicted intracellular mass. GH/IGF-I lowering treatment reduced intracellular mass and ventricular volume, without affecting other myocardial tissue characteristics. Discussion: Acromegaly results in a disease specific form of myocardial hypertrophy, characterized by an increase in intra- and extracellular mass, which is reversed after GH/IGF-I lowering treatment. This increase in ventricular mass is thus different to previous observations in essential hypertension. No differences in T2 times suggest against myocardial water retention in active acromegaly as explication of increased extracellular mass. Presentation: Thursday, June 15, 2023