Measurement of intracardiac pressures. State of the art--1986.
With Doppler echocardiography, through assessment of the velocity profile of flow in the region of stenoses, regurgitant lesions or shunts the pressure difference between two cardiac chambers or a cardiac chamber and great vessel can be calculated, using the Bernoulli equation. If the pressure in one chamber is known from clinical parameters, then the pressure in the second chamber can be estimated. In stenosis of the left ventricular outflow tract, the left ventricular systolic pressure can be calculated as the sum of the pressure difference between the left ventricle and aorta during systole and the cuff blood pressure. In right ventricular outflow tract obstruction, the velocity of blood flow can be used to derive the pressure gradient between the right ventricle and pulmonary artery during systole and, if the right ventricular systolic pressure is known, the pulmonary artery pressure can be estimated. This method is applicable in valvular and supravalvular stenoses, as well as for pulmonary artery bands or right ventricular-pulmonary artery conduits. If the right atrial pressure is known or estimated clinically as the jugular venous pressure, the right ventricular systolic pressure can be calculated; in the absence of right ventricular outflow tract obstruction from the velocity of a tricuspid regurgitation jet, this will approximate pulmonary artery systolic pressure. Further parameters for evaluation of pulmonary artery pressure are the isovolumetric right ventricular relaxation time or the relaxation time index (Burstin method) and the preejection period, acceleration time and right ventricular ejection time as derived from the pulmonary artery velocity profile.(ABSTRACT TRUNCATED AT 250 WORDS)
D001783:Blood Flow Velocity; D001794:Blood Pressure; D006328:Cardiac Catheterization; D004452:Echocardiography / Q000379:methods*; D006330:Heart Defects, Congenital / Q000175:diagnosis; D006331:Heart Diseases / Q000175:diagnosis*; D006349:Heart Valve Diseases / Q000175:diagnosis; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis; D011669:Pulmonary Wedge Pressure; D013599:Systole