Quantification of Mitral and Tricuspid Regurgitation Using Jet Centerline Velocities: An In Vitro Study of Jets in an Ambient Counterflow.

摘要: A method for quantifying mitral and tricuspid regurgitant volume that utilizes a measure of jet orifice velocity U(0) - m/sec), distal centerline (U(m) the intervening distance (X cm) was recently developed; where flow rate (Q(cal) L/min) is calculated as Q(cal) = (U(m)X)(2)/(26.46U(o)). This method, however, modeled free jet, whereas many atrial jets are counterflowing because opposing intra-atrial fields (counterflows). study concentrated on feasibility using quantification equation in atrium ambient may alter velocities reduce accuracy calculations. 4-cm wide chamber used to pump counterflows 0, 4, 22 cm/sec against 2.3, 4.8, 6.4 m/sec originating from 2-mm diameter orifice. For each counterflow-jet combination, were measured laser Doppler anemometry. (no counterflow), with 98% mean accuracy. all counterflow, calculation less accurate as: (i) ratio counterflow decreased (U(o)/U(c), U(c) velocity), i.e., relatively more intense, (ii) measurements made further But although lowered beneath values, it did so only significantly jet's portion (X/D > 16, >16 diameters origin jet). Thus, initial 93% >85% typical regurgitation, respectively. Counterflow lowers equivalent values. effect, most significant jet. Therefore, jets, not classically systolic inflow or jet-induced swirling flows, will decay their portions thus candidates technique. (ECHOCARDIOGRAPHY, Volume 13, July 1996)