Tricuspid valve disease with significant tricuspid insufficiency in the fetus: Diagnosis and outcome

AbstractThe echocardiographic studies and clinical course of 27 fetuses (mean gestationl age 26.9 weeks) diagnosed in utero with tricuspid valve disease and significant tricuspid regurgitation were reviewed. The diagnosis of Ebstein's anomaly was made in 17 of the fetuses, 7 had tricuspid valve dysplasia with poorly developed but normally attached leaflets and 2 had an unguarded tricuspid valve orifice with little or no identifiable tricuspid tissue. One fetus was excluded from data analysis because a more complex heart lesion was documented at autopsy. All fetuses had massive right atrial dilation and most who were serially studied had progressive right-sided cardiomegaly. Hydrops fetalis was found in six cases and atrial flutter in five.Associated cardiac lesions included pulmonary stenosis in five cases and pulmonary alresia in six. Four fetuses with normal forward pulmonary artery flow at the initial examination were found at subsequent study to have retrograde pulmonary artery and ductal flow in association with the development of pulmonary stenosis (n = 1) and pulmonary atresia (n = 3). On review of the clinical course of the 23 fetuses (excluding 3 with elective abortion), 48% of the fetuses died in utero and 35% who were liveborn died despite vigorous medical and, when necessary, surgical management, many of whom had severe congestive heart failure. Of the four infants who survived the neonatal period, three had a benign neonatal course, all of whom were diagnosed with mild to moderate Ebstein's anomaly; only one had pulmonary outflow obstruction. An additional finding at autopsy was significant lung hypoplasia documented in 10 of 19 autopsy reports.Tricuspid valve anomalies with tricuspid insufficiency can be identified echocardiographically in the fetus and should be searched for in the presence of right atrial enlargement. The prognosis for the fetus diagnosed in utero with significant tricuspid valve disease is extremely poor, with a prenatal course that includes progressive right heart dilation, with cardiac failure and lung hypoplasia in many and development of pulmonary stenose or pulmonary atresia later in gestation in some

747-4 Evaluation of Regurgitant Jets by Sound Intensity Using a Pulsatile Flow Model: Potential Contribution of Regurgitant Volume and Reynolds Number

Our goal in this study was to determine whether a new type of digital heart sound analysis method could give quantitative information about flow velocity and volume so as to allow a potentially lower-cost approach to followup studies of patients with stenotic or regurgitant valve lesions. To elucidate the relationships between hydrodynamic factors such as Reynolds number, flow velocity and flow volume and the sound characteristics of cardiac murmurs, we developed an in vitro pulsatile flow model with variable orifice size and shape (circular 0.11 cm2, 0.24 cm2, 1.77 cm2and 3.80 cm2; oval 0.24 cm2, with a ratio of major to minor axis=2; rectangular 0.24 cm2, ratio=4). Heart sounds were recorded with a new digital system (MCG) with real time spectral analysis and display and averaged over 15 “cardiac” cycles. Mean flow rate ranged from 0.6 l/min to 6 l/min. Actual instantaneous flow rate was measured using an ultrasonic flow meter for peak flow rates 1.6 l/min to 16.8 l/min. Reynolds number ranged from 6820 to 40050. For each orifice, there was an excellent relationship between total integrated sound energy (See figure: integration of intensity (I) and frequency (F) over time (T).) obtained by digital processing and Reynolds number, peak flow velocity and peak flow rate (r=0.89–0.97, 0.89–0.97, 0.93–D.99, P<0.001, respectively). The best relationship was obtained for the smallest orifice. Higher sound energies were detected for any given flow volume in asymmetrical orifices, probably due to higher turbulence. For all orifices combined, a correlation was found between peak frequency and peak velocity, but only total sound energywas correlated with peak flow rate (r=0.84, P<0.0t). Total integrated sound energy determined digitally is related to peak flow rate; peak velocity and Reynolds number parallel peak sound frequency

Validation of the accuracy of both right and left ventricular outflow volume determinations and semiautomated calculation of shunt volumes through atrial septal defects by digital color Doppler flow mapping in a chronic animal model

AbstractOBJECTIVESThe aim of the present study was to quantitate shunt flow volumes through atrial septal defects (ASDs) in a chronic animal model with surgically created ASDs using a new semiautomated color Doppler flow calculation method (ACM).BACKGROUNDBecause pulsed Doppler is cumbersome and often inappropriate for color flow computation, new methods such as ACM are of interest.METHODSIn this study, 13 to 25 weeks after ASDs were surgically created in eight sheep, a total of 24 hemodynamic states were studied at a separate open chest experimental session. Electromagnetic (EM) flow probes and meters were used to provide reference flow volumes as the pulmonary and aortic flow volumes (Qpand Qs) and shunt flow volumes (Qpminus Qs). Epicardial echocardiographic studies were performed to image the left and right ventricular outflow tract (LVOT and RVOT) forward flow signals. The ACM method digitally integrated spatial and temporal color flow velocity data to provide stroke volumes.RESULTSLeft ventricular outflow tract and RVOT flow volumes obtained by the ACM method agreed well with those obtained by the EM method (r = 0.96, mean difference = 0.78 ± 1.7 ml for LVOT and r = 0.97, mean difference = −0.35 ± 3.6 ml for RVOT). As a result, shunt flow volumes and Qp/Qsby the ACM method agreed well with those obtained by the EM method (r = 0.96, mean difference = −1.1 ± 3.6 ml/beat for shunt volumes and r = 0.95, mean difference = −0.11 ± 0.22 for Qp/Qs).CONCLUSIONSThis animal study, using strictly quantified shunt flow volumes, demonstrated that the ACM method can provide Qp/Qsand shunt measurements semiautomatically and noninvasively