Myocardial haemodynamic responses to dobutamine stress compared to physiological exercise during cardiac magnetic resonance imaging

Background Pharmacological methods remain the most common methods of inducing myocardial stress, and remain the gold standard for diagnostic purposes in the MR-environment. MR compatible ergometers now permit CMR to be performed during exercise stress, allowing physiological responses to exercise to be studied. Inotropic agents such as dobutamine are widely used in low-output states such as cardiogenic shock. However, this has consistently been shown to worsen patient outcomes. Though the effects of dobutamine are thought to mimic that of exercise stress, exercise is known to have a beneficial effect on patient outcomes. The aim of this study was to investigate the effects of these two stress methods on myocardial haemodynamics and deformation to gain insight as to factors that may contribute to their differing impacts on prognosis.