Left ventricular diastolic function and cardiac performance during exercise in patients with acromegaly

Exercise-induced impairment of left ventricular (LV) ejection fraction is common in patients with acromegaly and normal resting systolic function. This study aimed to clarify whether diastolic dysfunction plays a role in the abnormal adaptation to exercise in these patients. Forty-eight patients with active acromegaly underwent LV radionuclide angiography at rest and during exercise. Doppler echocardiography was also performed to assess LV mass index and diastolic function by combined analysis of mitral and pulmonary flow velocity curves. LV ejection fraction at peak exercise was related to rest ejection fraction (r = 0.78; P< 0.001), peak filling rate (r = 0.55; P< 0.01), LV mass index ( r = -0.56; P < 0.001), and the difference between duration of diastolic reverse pulmonary vein flow and mitral flow at atrial contraction ( Delta duration) ( r = - 0.54; P < 0.01). At stepwise regression analysis, rest ejection fraction and Delta duration were the only variables that independently influenced ( P < 0.001) ejection fraction at peak exercise.