To assess left ventricular (LV) diastolic filling at rest in patients with coronary artery disease (CAD), we analyzed high-resolution time-activity curves (10-20 msec/frame) obtained from gated radionuclide angiograms in 231 patients. Peak LV filling rate (PFR), expressed in end-diastolic volumes per second (EDV/sec), was subnormal in CAD patients (1.8 +/- 0.6 [+/- SD] vs normal mean of 3.3 +/- 0.6, p les than 0.001) and time to PFR (TPFR), measured from end-systole to PFR, was prolonged (171 +/- 41 msec vs normal mean of 136 +/- 23 msec, p less than 0.001). These indexes were also abnormal in the 141 patients with normal resting LV ejection fraction (PFR = 2.1 +/- 0.5 EDV/sec; TPFR = 175 +/- 36 msec) and in 123 patients without Q waves on the ECG (PFR = 2.1 +/- 0.5 EDV/sec; TPFR = 168 +/- 38 msec). Abnormal LV filling at rest (PFR less than 2.5 EDV/sec or TPFR greater than 180 msec) was found in 91% of all patients with CAD, 86% of patients with normal resting LV ejection fractions, 85% of patients without Q waves, and 82% of patients with normal resting LV ejection fraction, no resting regional wall motion abnormalities and no Q waves. Thus, LV diastolic filling, evaluated noninvasively by radionuclide angiography, is abnormal in a high percentage of patients with CAD at rest independent of LV systolic function or previous myocardial infarction.