Quantitative coronary angiography: Technical issues
- Morton J Kern, MD, MSCAI, FAHA, FACC
Morton J Kern, MD, MSCAI, FAHA, FACC
- Professor of Medicine
- University of California, Irvine
A reduction in the coronary artery luminal cross-sectional diameter, estimated by the visual inspection of the radiocontrast column or lumenogram during conventional angiography, has been utilized to formulate predictions about clinical presentations and stress-induced reductions in coronary blood flow. Anatomic and physiologic approaches to coronary artery disease are complementary but because of numerous factors not evident from angiography (eg, length, entrance angle, coefficient of separation of laminar flow) comparison data yield contradictory results. As a result, quantitative approaches to the angiographic evaluation of coronary anatomy are infrequently employed on a routine daily basis in most laboratories. The greatest advantage of quantitative coronary angiography is its theoretical freedom from observer influences and bias, thereby minimizing significant potential intraobserver and interobserver variability.
The technical issues related to quantitative coronary angiography will be reviewed here. The clinical utility of this procedure is discussed separately. (See "Quantitative coronary angiography: Clinical applications".)
Many techniques are available for computer applications that permit quantification of coronary stenosis . A quantitative analysis of the angiogram requires some form of optical magnification of the cineangiographic image which, in turn, permits computer-assisted definition and quantitation of disease severity. With the off-line techniques, image acquisition proceeds in the conventional manner, with the generation of a digital cineangiogram displayed on the image processor. Digital quantitation of selected image frames can be made with or without electronic magnification, easily accomplished with modern digital quantitative software and analysis systems.
A two-times magnification factor is utilized in most laboratories, without regard to the optical system employed. The positioning of the camera and selection of the lens system is usually accomplished manually. After digitization, and prior to computer analysis, the images are stored in a specifically designed image processing system. These systems vary in complexity and cost, and are available with a large selection of hardware and software.
On-line digital systems and computer application packages have become widely available through commercial distribution. These systems are designed to facilitate accurate clinical analysis of thrombolysis, stent deployment, and other endovascular interventions. The major impediment to universal application of on-line quantitation has been image quality. Advances in image-enhancement continue to refine the utility of on-line quantitation.
- Reiber, JH, Kooijman, CJ, Slager, CJ, et al. Computer-assisted analysis of the severity of obstructions from coronary cineangiograms: A methodological review. Automedica 1984; 5:219.
- Nichols AB, Gabrieli CF, Fenoglio JJ Jr, Esser PD. Quantification of relative coronary arterial stenosis by cinevideodensitometric analysis of coronary arteriograms. Circulation 1984; 69:512.
- Ellis S, Sanders W, Goulet C, et al. Optimal detection of the progression of coronary artery disease: comparison of methods suitable for risk factor intervention trials. Circulation 1986; 74:1235.
- Kirkeeide, RL, Fung, P, Smalling, RW, Gould, KL. Automated evaluation of vessel diameter from arteriograms. Comput Cardiol 1982; 5:215.
- LeFree MT, Simon SB, Lewis RJ, et al.. Digital radiographic coronary artery quantification. Comput Cardiol 1985; 99.
- Brown BG, Bolson E, Frimer M, Dodge HT. Quantitative coronary arteriography: estimation of dimensions, hemodynamic resistance, and atheroma mass of coronary artery lesions using the arteriogram and digital computation. Circulation 1977; 55:329.
- Sanders, WJ, Alderman, EL, Harrison, DC. Coronary artery quantitation using digital image processing techniques. Comput Cardiol 1979; 7:15.
- Wollschlager H, Lee P, Zeiher A, et al.. Improvement of quantitative angiography by exact calculation of radiological magnification factors. Comput Cardiol 1985; 483.
- Serruys PW, Reiber JH, Wijns W, et al. Assessment of percutaneous transluminal coronary angioplasty by quantitative coronary angiography: diameter versus densitometric area measurements. Am J Cardiol 1984; 54:482.
- Peters RJ, Kok WE, Pasterkamp G, et al. Videodensitometric quantitative angiography after coronary balloon angioplasty, compared to edge-detection quantitative angiography and intracoronary ultrasound imaging. Eur Heart J 2000; 21:654.
- Beatt KJ, Luijten HE, de Feyter PJ, et al. Change in diameter of coronary artery segments adjacent to stenosis after percutaneous transluminal coronary angioplasty: failure of percent diameter stenosis measurement to reflect morphologic changes induced by balloon dilation. J Am Coll Cardiol 1988; 12:315.
- Reiber JHC, Serruys PW, Slager CJ. Quantitative Coronary and Left Ventricular Cineangiography: Methodology and Clinical Applications, Martinus Nijhoff, Boston 1986.
- Crawford DW, Brooks SH, Selzer RH, et al. Computer densitometry for angiographic assessment of arterial cholesterol content and gross pathology in human atherosclerosis. J Lab Clin Med 1977; 89:378.
- Reiber JH, Kooijman CJ, Slager CJ, et al. Coronary artery dimensions from cineangiograms methodology and validation of a computer-assisted analysis procedure. IEEE Trans Med Imaging 1984; 3:131.
- Reiber JHC. Morphologic and densitometric quantitation of coronary stenoses: An overview of existing quantitation techniques. In: New Developments in Quantitative Coronary Arteriography, Reiber JHC, Serruys PW (Eds), Martinus Nijhoff, Dordrecht 1988. p.34.
- Kishon Y, Yerushalmi S, Deutsch V, Neufeld HN. Measurement of coronary arterial lumen by densitometric analysis of angiograms. Angiology 1979; 30:304.
- Doriot PA, Suilen C, Guggenheim N, et al. Morphometry versus densitometry--a comparison by use of casts of human coronary arteries. Int J Card Imaging 1992; 8:121.
- Di Mario C, Haase J, den Boer A, et al. Edge detection versus densitometry in the quantitative assessment of stenosis phantoms: an in vivo comparison in porcine coronary arteries. Am Heart J 1992; 124:1181.
- Mancini GB, Simon SB, McGillem MJ, et al. Automated quantitative coronary arteriography: morphologic and physiologic validation in vivo of a rapid digital angiographic method. Circulation 1987; 75:452.
- Haase J, Di Mario C, Slager CJ, et al. In-vivo validation of on-line and off-line geometric coronary measurements using insertion of stenosis phantoms in porcine coronary arteries. Cathet Cardiovasc Diagn 1992; 27:16.
- Reiber JH, Serruys PW, Kooijman CJ, et al. Assessment of short-, medium-, and long-term variations in arterial dimensions from computer-assisted quantitation of coronary cineangiograms. Circulation 1985; 71:280.
- Syvänne M, Nieminen MS, Frick MH. Accuracy and precision of quantitative arteriography in the evaluation of coronary artery disease after coronary bypass surgery. A validation study. Int J Card Imaging 1994; 10:243.
- Foley DP, Deckers J, van den Bos AA, et al. Usefulness of repeat coronary angiography 24 hours after successful balloon angioplasty to evaluate early luminal deterioration and facilitate quantitative analysis. Am J Cardiol 1993; 72:1341.
- Foley DP, Escaned J, Strauss BH, et al. Quantitative coronary angiography (QCA) in interventional cardiology: clinical application of QCA measurements. Prog Cardiovasc Dis 1994; 36:363.
- Wijns W, Serruys PW, Reiber JH, et al. Quantitative angiography of the left anterior descending coronary artery: correlations with pressure gradient and results of exercise thallium scintigraphy. Circulation 1985; 71:273.
- Baptista J, Arnese M, Roelandt JR, et al. Quantitative coronary angiography in the estimation of the functional significance of coronary stenosis: correlations with dobutamine-atropine stress test. J Am Coll Cardiol 1994; 23:1434.