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' fronn 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 <= 7 than in patients with MET > 7 (all P < 0.05). Conclusion Systolic and diastolic velocities measured by TD 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.