Alteration of diastolic filling rate during exercise radionuclide angiography: a highly sensitive technique for detection of coronary artery disease

Diastolic and systolic parameters of left ventricular performance were characterized from high-frequency time-activity curves obtained in 10 normal volunteers (mean age 29 +/- 4 yr), in 25 patients with normal coronary arteries, and in 50 patients with coronary artery disease (CAD) at rest and during three stages of exercise radionuclide angiography. In the normal volunteers ejection fraction was 65 +/- 5% (SD) at rest and 78 +/- 5% with exercise (p less than .001). In patients with normal coronary arteries ejection fraction was 64 +/- 5% at rest and 72 +/- 8% with exercise (p less than .0001). In patients with CAD resting ejection fraction was 60 +/- 10% and that during exercise was 61 +/- 13% (p = NS). Peak diastolic filling rate in the first half of diastole, peak systolic ejection rate, and times to peak rates and to end-systole were measured. In the normal subjects resting peak diastolic filling rate was 3.1 +/- 0.6 end-diastolic counts/sec and it increased in all subjects with exercise to 3.6 +/- 0.7 (p less than .05). In patients with normal arteries and those with CAD peak diastolic filling rate was 2.3 +/- 0.8 at rest and with exercise this parameter increased to 3.2 +/- 1.1 (p less than .001) in patients with normal arteries and fell to 1.7 +/- 0.6 in those with CAD (p less than .001). Peak systolic ejection rate decreased from 2.5 +/- 0.8 to 1.9 +/- 0.8 with exercise in patients with CAD (p less than .001).