Real time three-dimensional stress echocardiography: A new approach for assessing diastolic function

Objective: To assess the feasibility of utilizing real time three-dimensional echocardiography (RT3DE) for assessment of diastolic function during stress. Methods: Rest and stress volumes were acquired in 24 patients and parameters of diastolic function-peak ventricular filling rate (PFR) and time to peak filling rate (TPFR)-were calculated. Results: Calculation of diastolic parameters was feasible in all patients. Resting PFR correlated with end-diastolic (EDV) and stroke volumes and inversely with TPFR (r = 0.53, 0.66, -0.5). With stress, PFR increased by 93% and TPFR decreased by 23% (P < 0.001). Stress PFR correlated with stress heart rate, EDV and stroke volume (r = 0.52, 0.50, 0.62) while TPFR correlated inversely with heart rate (r =-0.71). The change in PFR with stress correlated with the change in stroke volume (r = 0.42), while the change in TPFR correlated with the change in end-systolic volume (ESV) (r = 0.43) and inversely with the change in diastolic blood pressure (r =-0.41). Rest and stress PFR and TPFR are independent of age, gender and blood pressure and the change in PFR is independent of stress heart rate or blood pressure. E/E′ correlated with stress TPFR (r = 0.72) and change in TPFR (r = 0.67) and inversely with change in PFR (r =-0.67). Conclusions: RT3DE can assess diastolic function during stress by detecting changes in PFR and TPFR, independent of gender, age, and blood pressure. The changes in these parameters with stress are influenced by baseline filling pressures. Larger studies are required to validate the clinical significance of these observations.