Image selection for volume calculations in digital ventriculography

The author describes a computer-assistance program for the selection of images to use in the calculation of cardiac parameters. Heart cycles with varying time intervals from end-systole to end-diastole may have end-diastolic volume variations, even though the contraction and relaxation patterns are normal. Thus it may be difficult to select the optimal beat from visual inspection of the image sequence only. The program calculates the points of time for end-diastole using image data. Using criteria for RR-intervals, the optimal images are found. The program needs minimal operator intervention and takes three minutes for a calculation based on 200 images. The quality of the computer output can be checked by inspection of the time-density diagram