Association between cardiac functional capacity and parameters of tissue Doppler imaging in patients with normal ejection fraction.

OBJECTIVE: Patients with normal ejection fraction (EF) by conventional echocardiography may present with symptoms and findings of decreased cardiac functional capacity. We aimed to investigate the association between cardiac functional capacity determined by cardiopulmonary exercise test (CPET) and parameters of tissue Doppler (TD) imaging in patients with normal EF.
METHODS: In all, 52 patients with normal EF were included. Conventional and TD imaging were performed. Peak systolic (S), early (E') and late (A') diastolic velocities were obtained from septal and lateral mitral annulus and tricuspid annulus by pulsed-wave TD. CPET was performed. Exercise time, peak oxygen consumption (peak VO2), anaerobic threshold (AT), metabolic equivalents (MET) values were determined and were compared with TD imaging parameters.
RESULTS: We did not find any association between conventional echocardiographic measurements and cardiac functional capacity. However, peak S, E' and A velocity from the septal and tricuspid annulus and E' velocity from the lateral annulus correlated with exercise time, peak VO2, AT and MET (all P < 0.05). E/E' from the left ventricle correlated inversely with exercise time, peak VO2, AT and MET (all P < 0.05). S, E, A' velocities from septal and tricuspid annulus, E' velocity from lateral annulus were lower in patients with MET < or = 7 than in patients with MET > 7 (all P < 0.05).
CONCLUSION: Systolic and diastolic velocities measured byTD imaging correlated with cardiac functional capacity as determined by CPET in patients with normal EF by conventional echocardiography. TD imaging could be more susceptible to determine cardiac functional capacity in these patients.