Validation of a Doppler echocardiographic method for calculating severity of discrete stenotic obstructions in a canine preparation with a pulmonary arterial band.

Abstract

The purpose of this study was Vol. 69, No. 6, June 1984 in tracking changes in gradients within the same animal was also analyzed. MethodsSurgical technique in the animal preparation. Six mongrel dogs weighing 20 to 30 kg were anesthetized with intravenous sodium pentobarbitol (30 mg/kg), intubated, and ventilated with a standard volume respirator. After a median sternotomy, the pericardium of each dog was opened and the heart was exposed. The ascending aorta and the main pulmonary artery were dissected and cleaned of fat and adventitia and an appropriately sized, precalibrated electromagnetic flow probe (GouldStatham SP2204) was placed around the ascending aorta approximately 2 cm above the aortic valve to continuously monitor cardiac output. Catheter-tipped micromanometers (Millar) or fluid-filled catheters connected to strain-gauge transducers (Statham P231D) were placed in the right ventricle, pulmonary artery, and aorta to record pressures continuously. Umbilical tape (l/' inch) was sewn to the posterior rim of the pulmonary artery just above the valve anulus and progressively tightened to produce varying degrees of stenosis. After each degree of constriction of the pulmonary arterial band, the animal was allowed at least 2 min to stabilize and adapt to

Plasma N-Terminal Pro B-Type Natriuretic Peptide Concentrations in Dogs with Pulmonic Stenosis

“…However, invasive assessment is uncommonly available in veterinary medicine, because they require general anesthesia and carry a risk of life-threatening complications. In contrast, the continuous wave Doppler-derived peak PG system, which measures the PG across the pulmonic valve as an indirect assessment of hemodynamics [8, 14, 21, 28], is essential method to diagnose the severity of PS in dogs [10, 17]. Francis et al reported that the Doppler-derived PG increases in proportion to the degree of PS in dogs [10].…”

“…The size of the Doppler sample volume was set at an axial length of 2 mm. The trans-pulmonic valve PG was calculated by modified Bernoulli’s equation (PG=4 × (peak PS velocity 2 ) [28]. …”

“…Echocardiographic examination is essential method to diagnose the PS in dogs [10, 17]. Continuous wave Doppler is using to assess the pressure gradient (PG) across the pulmonic valve, which indicates the severity of stenosis [9, 14, 21, 28]. The main limitation of Doppler-derived PG is that they require a high technique of echocardiography.…”

Evaluation of plasma N-terminal pro-brain natriuretic peptide and troponin I concentrations in dogs with congenital ventricular outflow tract stenosis

“…The pressure gradient (PG) across the stenotic valve has been found to be well correlated to the severity of stenosis [22,25]. Therefore, in this study, we sub-grouped our study population, based on the PG across the stenotic valve.…”

Retrograde transfemoral catheterization of the left ventricle in children with aortic valve stenosis

“…Its management depends on the severity of the obstruction which can be assessed by measuring the pressure gradient across the aortic valve [9,10] and calculating the valve orifice area by Gorlin's formula [5] . Although the transaortic valvar pressure gradient can be assessed roughly by Doppler echocardiography [11], direct retrograde catheterization of the left ventricle remains the most accurate and widely adopted method of assessing the severity and morphology of the aortic valve lesion . Much has already been published on the technique of crossing the stenotic aortic valve in adult patients [1,2,3,[6][7][8], but little has been written on such procedure in children .…”