ONLINE QUANTITATIVE CORONARY ANALYSIS IN CLINICAL-PRACTICE - ONE-STEPCLOSER TO REALITY

Quantitative coronary analysis is widely used in studies of progressio n/regression and restenosis of coronary lesions. On-line digital syste ms are used in diagnostic coronary angiography, and as a guide in coro nary interventions. The aim of this investigation was to test the reli ability of measures obtained with one commercially available on-line e quipment. Well-visualized coronary lesions from patient studies were a nalyzed for variability in single-frame measurement. Procedural factor s affecting the consistency of measurements were identified by repeate d visualization of the same coronary lesion with hand-and power-inject ion of contrast in various positions in the field of the image intensi fier, and by imaging of steel phantoms in the same positions. Steel ph antoms closely resembling coronary lesions as encountered in practice were visualized in the most favourable radiologic setting compatible w ith clinical situations. Accuracy and precision of measurements were f ound to be worse than reported in validation studies. This may be due to a host of variables which may need to be tested in each laboratory performing on-line quantitative coronary angiography, when data so obt ained are to be used in clinical decision making or in research studie s. (C) 1994 Wiley-Liss, Inc.