Objective: To verify whether tissue Doppler imaging (TDI) could contribute to a better understanding of the natural history of cardiomyopathy in active Cushing's disease (CD), through its enhanced sensitivity to diastolic dysfunction, and identifying preliminary regional signs of systolic dysfunction before the appearance of clinical symptoms of cardiac pathologies.
Methods: Eleven women with newly diagnosed CD and 32 control cases, purposely matched for gender, age, body mass index and co-incidental diseases were enrolled in this study. Echocardiographic examinations were assessed by conventional echocardiography and tissue Doppler imaging. The peak systolic velocity (S'm), early diastolic myocardial peak velocity (E'm), late diastolic myocardial peak velocity (A'm), isovolumic acceleration (IVA), myocardial pre-contraction time (PCT'm), myocardial contraction time (CT'm) and myocardial relaxation time (RT'm) were measured at septal and lateral mitral anulus.
Results: In TDI, E'm and, E'm/A'm ratio were significantly lower, and PCT'm/CT'm ratio was higher, S'm, A'm, peak early diastole/E'm ratio, PCT'm, and isovolumetric myocardial relaxation time values were similar at lateral and septal anulus in patients with CD than controls (p>0.05). Lateral and septal anulus IVA were significantly lower in patients with CD than the control group (p<0.05). Correlation analysis showed that IVA time at lateral anulus correlated positively with S'm at lateral anulus (r=0.58; p=0.002) and IVA time at septal anulus correlated positively with S'm at septal anulus (r=0.51; p=0.008).
Conclusion: Our study confirms that patients with CD have impaired diastolic function. More importantly, we also demonstrated an impairment of myocardial systolic function in patients with CD by TDI. We recommend using TDI in addition to conventional echocardiography parameters for the cardiovascular risk assessment of patients with Cushing' syndrome.