Evaluation of end-diastolic left ventricular volume in equilibrium gated radionuclide cardiography

The image of the left ventricle in the end-diastole during an equilibrium gated radionuclide cardiography (EGRC) was used for evaluation of the left ventricular end-diastolic volume (EDV). The method consists of a summation of the small volumes represented by each pixel in the activity image stored in the computer. The method was adapted to a normal material of 61 women 40-80 years. EDV was 69 +/- 17 ml/m2 (means +/- 1 SEE) and did not correlate with age. The relative experimental accuracy of the single determination of EDV was 7%-16% depending on the size of EDV. The method was verified in a control group of 25 subjects without valve malfunctions of the left ventricle according to echocardiography. The results from an abnormal material of 38 subjects with verified or suspected valve malfunctions of the left ventricle demonstrated the application of EGRC and the preceding first-pass radionuclide cardiography (FPRC) for determination of left ventricular regurgitation. Intra-observer variability of EDV was unbiased with a standard error of estimate of 12% for normal EDV and 5% for enlarged EDV.