Quantitative analysis of semi-supine exercise echocardiography - influence of age on myocardial Doppler imaging indices

Objectives - This study was performed to evaluate the feasibility of quantitative analysis of exercise echocardiography using pulsed wave Doppler myocardial imaging (DMI) and to examine the relation between age and DMI parameters at rest and during graded exercise in normal subjects. Methods and results - Seventy-two healthy volunteers were divided into three age groups (group 1, age :5 40 years, group 11, age 41 - 59 years and group 111, age : 60 years), and underwent a semisupine exercise echocardiogram. Peak systolic velocity (SV), time to peak SV (TPV), systolic velocity time integral (VTI) and peak diastolic velocities (V-E and V-A) were measured off-line. There was a heterogeneity in DMI parameters between different myocardial walls and a gradient was found between basal and mid segments. Both persisted during exercise. Group I had significantly higher TPV than groups II and III. Increase in workload was accompanied by an increase in velocities, while TPV decreased. Differences between groups persisted throughout exercise. Conclusions - Off-line measurements of DMI parameters are feasible during exercise. SV and E decline as age increases while A increases. SV already increases at low charge exercise and may serve as a quantitative marker for the detection of myocardial viability. Change of the absolute DMI velocity values during exercise may provide a better indicator of ischaemia or viability than the absolute values themselves.