Prognostic significance of contractile reserve assessed by dobutamine-induced changes of Tei index in patients with idiopathic dilated cardiomyopathy

Aims To determine prognostic significance of global left ventricular (LV) contractile reserve, defined by dobutamine-induced changes of Tei index (ΔTei), in patients with dilated cardiomyopathy (DCM). Methods and results Thirty-eight patients with idiopathic DCM underwent high-dose (up to 40 µg/kg/min) dobutamine stress echocardiography. Prognostic value of different indices of LV contractile reserve, including ΔTei, as well as changes of ejection fraction (ΔEF) and wall motion score index (ΔWMSi), was analysed. Patients were followed up for 5 years for cardiac mortality. Patients with preserved contractile reserve, defined by ΔTei > −0.35, had significantly lower cardiac mortality when compared with those without it (38 vs. 77%, P = 0.02). Also, the Kaplan–Meier survival analysis revealed that patients with contractile reserve had better 5-year survival when compared with those without contractile reserve (log-rank = 6.01, P = 0.014). However, of all examined indices of contractile reserve, Cox's regression analysis identified ΔWMSi as the only independent predictor of 5-year mortality. Conclusion Our data indicate that the presence of contractile reserve assessed by ΔTei may identify patients with favourable long-term prognosis. Prognostic value of ΔTei appears to be similar to ΔEF, but less powerful than ΔWMSi.