Abstract
With the aims to create a reference population for radionuclide left (ECG-gated) and
right (first-pass) ventriculography and to identify independent determinants of normal
left and right ventricular (LV; RV) function indices, 50 healthy volunteers aged 21–69
years underwent gamma camera recordings after 30 min of rest (‘R’) and during submaximal
semi-supine bicycle exercise (‘E’). From ‘R’ to ‘E’ LV ejection fraction (EF) rose
from 0.68 ± 0.04 to 0.78 ± 0.04 (p < 0.0001; Δ LVEF ≥ 0.05 in all). General descriptive
data and measures of exercise capacity and of preload and afterload were entered as
independent co-variates in a multiple linear regression model. LV peak filling rate
(PFR) ‘R’, LV fast filling fraction (FFF) ‘R’, and Δ RVEF decreased significantly
with age while time-to-PFR (T-PFR) ‘R’, systole-to-heart cycle duration ratio (SC-ratio)
‘R’, and mean pulmonary transit time (PTT) ‘R’ + ‘E’ increased. Women had shorter
time-to-peak ejection rate (T-PER) ‘R’ and higher SC-ratio ‘R’ than men, while obesity
was related to higher Δ RVEF and regular weekly exercise to higher FFF ‘E’. Tobacco
smoking was of no influence. T-PFR ‘R’ + ‘E’ and SC-ratio ‘E’ decreased with maximal
aerobic power while LVEF ‘E’, peak ejection rate ‘E’, and Δ RVEF increased. FFF ‘R’
and RVEF ‘R’ + ‘E’ increased with normalized peak work load, while Δ LVEF increased
with watt-exercise time product. Measures of preload and afterload had modulating
influences on the LV and RV function indices (‘R’ + ‘E’).
Age exerted a negative influence on LV diastolic function at rest with an accompanying
prolongation of pulmonary transit time. Maximal aerobic power and other measures of
exercise capacity were directly related to increased left ventricular diastolic function
and right ventricular systolic function at rest as well as during exercise, and to
left ventricular systolic function during exercise.
