Echocardiographic estimation of systemic systolic blood pressure in dogs with mild mitral regurgitation.
BACKGROUND
Systemic hypertension is likely underdiagnosed in veterinary medicine because systemic blood pressure is rarely measured. Systemic blood pressure can theoretically be estimated by echocardiography. According to the modified Bernoulli equation (PG = 4v(2)), mitral regurgitation (MR) velocity should approximate systolic left ventricular pressure (sLVP), and therefore systolic systemic blood pressure (sSBP) in the presence of a normal left atrial pressure (LAP) and the absence of aortic stenosis. The aim of this study was to evaluate the use of echocardiography to estimate sSBP by means of the Bernoulli equation.


OBJECTIVE
Systemic blood pressure can be estimated by echocardiography.


METHODS
Seventeen dogs with mild MR. No dogs had aortic or subaortic stenosis, and all had MR with a clear continuous-wave Doppler signal and a left atrial to aorta ratio of < or = 1.6.


METHODS
Five simultaneous, blinded continuous-wave measurements of maximum MR velocity (Vmax) and indirect sSBP measurements (by Park's Doppler) were obtained for each dog. Pressure gradient was calculated from Vmax by means of the Bernoulli equation, averaged, and added to an assumed LAP of 8 mm Hg to calculate sLVP.


RESULTS
Calculated sLVP was significantly correlated with indirectly measured sSBP within a range of 121 to 218 mm Hg (P = .0002, r = .78). Mean +/- SD bias was 0.1 +/- 15.3 mm Hg with limits of agreement of -29.9 to 30.1 mm Hg.


CONCLUSIONS
Despite the significant correlation, the wide limits of agreement between the methods hinder the clinical utility of echocardiographic estimation of blood pressure.
Tou
Sandra P
SP
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, USA. tou@asgrets.com
Adin
Darcy B
DB
Estrada
Amara H
AH
D000818:Animals; D001795:Blood Pressure Determination / Q000379:methods / Q000662:veterinary*; D004283:Dog Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004285:Dogs; D018618:Echocardiography, Doppler, Color / Q000662:veterinary*; D005260:Female; D008297:Male; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000662:veterinary*; D017725:Ventricular Pressure / Q000502:physiology