Previous applications of digital subtraction angiography (DSA) to the assessment of ventricular function, particularly during exercise, have been limited by cardiac, respiratory, and gross patient motion. Dual-energy DSA, however, is insensitive to motion, and makes DSA imaging readily applicable to cardiac patients. For the first time, dual-energy subtraction is available in a clinical cardiac catheterization laboratory. The purpose of this research is to apply the dual-energy technique to patients with cardiac disease, and quantitatively assess both global and regional left ventricular function during rest and exercise. More specifically, the aims are: Firstly, exploiting the motion immunity of this technique, it is proposed to develop and apply a digital subtraction dual-energy ventriculographic exercise stress test using a right heart catheter. This exercise test will be utilized to assess the functional significance of coronary stenoses at the time of cardiac catheterization. Secondly, a videodensitometric analysis of dual-energy subtraction images is under investigation to test the hypothesis that absolute global left ventricular volumes can be accurately measured independent of geometric assumptions, This will be done using a direct measure of blood iodine concentration. Thirdly, it will be determined whether accurate volume measurements can be made without direct sampling of the blood iodine concentration. Thus, absolute volume determinations may be possible without the need of arterial catheterization. Fourthly, a phase-matched rest/exercise wall motion display is being developed to quantitate regional myocardial function independent of cardiac coordinate systems. Phase- matching refers to the superposition of two images at the same point in the cardiac cycle, one at rest and one during exercise. The results of this research will provide improved methods of assessing the functional significance of coronary stenoses in patients. Furthermore, these techniques have the potential to provide a high resolution outpatient test for coronary artery disease and for the serial assessment of rest and exercise ventricular function in patients with cardiac disease.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL038409-05
Application #
3354642
Study Section
Diagnostic Radiology Study Section (RNM)
Project Start
1987-04-01
Project End
1993-03-31
Budget Start
1991-04-01
Budget End
1992-03-31
Support Year
5
Fiscal Year
1991
Total Cost
Indirect Cost
Name
University of Wisconsin Madison
Department
Type
Schools of Medicine
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715
Van Lysel, M S (1994) Optimization of beam parameters for dual-energy digital subtraction angiography. Med Phys 21:219-26
Horton, J D; Cuthbert, J A; Spady, D K (1994) Regulation of hepatic 7 alpha-hydroxylase expression by dietary psyllium in the hamster. J Clin Invest 93:2084-92
van Lysel, M S; Miller, W P; Fuerst, T P et al. (1994) Improved densitometric measurement of left ventricular ejection fraction using dual-energy digital subtraction angiography. Int J Card Imaging 10:113-21
McCollough, C H; Miller, W P; Van Lysel, M S et al. (1993) Densitometric assessment of regional left ventricular systolic function during graded ischemia in the dog by use of dual-energy digital subtraction ventriculography. Am Heart J 125:1667-75
Fuerst, T P; Van Lysel, M S (1993) Measurement of absolute blood iodine concentration during digital subtraction ventriculography. Med Phys 20:795-803
Spady, D K; Woollett, L A; Dietschy, J M (1993) Regulation of plasma LDL-cholesterol levels by dietary cholesterol and fatty acids. Annu Rev Nutr 13:355-81
Horton, J D; Cuthbert, J A; Spady, D K (1993) Dietary fatty acids regulate hepatic low density lipoprotein (LDL) transport by altering LDL receptor protein and mRNA levels. J Clin Invest 92:743-9
Spady, D K; Cuthbert, J A (1992) Regulation of hepatic sterol metabolism in the rat. Parallel regulation of activity and mRNA for 7 alpha-hydroxylase but not 3-hydroxy-3-methylglutaryl-coenzyme A reductase or low density lipoprotein receptor. J Biol Chem 267:5584-91
Van Lysel, M S; Miller, W P; Senior, D G et al. (1991) Left ventricular dual-energy digital subtraction angiography: a motion immune digital subtraction technique. Int J Card Imaging 7:55-65
McCollough, C H; Van Lysel, M S; Peppler, W W et al. (1989) A correlated noise reduction algorithm for dual-energy digital subtraction angiography. Med Phys 16:873-80