title: Comparison of catheterization and Doppler-derived pressure gradients in a canine model of subaortic stenosis.
abstract: The relationship between Doppler-estimated and catheterization-measured pressure gradients was examined by repeated-measures linear regression analysis and difference plots in 15 dogs with naturally occurring subvalvular aortic stenosis. Thirty left ventricular outflow tract gradients were compared during sinus rhythm and 142 gradients during premature or postextrasystolic beats for the following pairs of data: (1) mean catheterization gradient versus mean Doppler gradient, (2) maximal instantaneous catheterization gradient versus maximal Doppler gradient, and (3) peak-to-peak catheterization gradient versus maximal Doppler gradient. The correlation between Doppler-derived and catheterization-derived pressure gradients was excellent (r = 0.99; p < 0.001) for the maximal instantaneous (sinus rhythm: standard error of the estimate [SEE] = 5.7 mm Hg; premature and postextrasystolic beats: SEE = 6.7 mm Hg) and mean gradients (sinus rhythm: SEE = 3.6 mm Hg; premature and postextrasystolic beats: SEE = 4.5 mm Hg). There was also a strong correlation between the peak-to-peak catheterization gradient and the maximal Doppler gradient (sinus rhythm: r = 0.99, p < 0.001, SEE = 5.3 mm Hg; premature and postextrasystolic beats: r = 0.97, p < 0.001, SEE = 7.2 mm Hg). Agreement between the two techniques was best for mean gradients and most disparate for the comparisons of maximal Doppler gradients and peak-to-peak catheterization gradients.
authors.affiliation: Department of Veterinary Clinical Sciences, Ohio State University College of Veterinary Medicine, Columbus, USA.
authors.forename: L B
authors.initials: LB
authors.lastname: Lehmkuhl
authors.forename: J D
authors.initials: JD
authors.lastname: Bonagura
authors.forename: D E
authors.initials: DE
authors.lastname: Jones
authors.forename: R L
authors.initials: RL
authors.lastname: Stepien
mesh_terms: D000818:Animals; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000662:veterinary; D001783:Blood Flow Velocity; D001794:Blood Pressure; D006328:Cardiac Catheterization; D005117:Cardiac Complexes, Premature / Q000000981:diagnostic imaging / Q000503:physiopathology; D002302:Cardiac Output; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000662:veterinary; D002404:Catheterization; D004283:Dog Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology; D004285:Dogs; D015150:Echocardiography, Doppler; D005260:Female; D006339:Heart Rate; D016014:Linear Models; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D013318:Stroke Volume; D017725:Ventricular Pressure