Quantitative Assessment of Left Ventricular Dysfunction in Fetal Ebstein's Anomaly and Tricuspid Valve Dysplasia.

BACKGROUND: Fetal Ebstein's anomaly and tricuspid valve dysplasia (EA/TVD) are associated with high perinatal mortality relative to pulmonary atresia with intact ventricular septum (PAIVS), despite both requiring redistribution of the cardiac output (CO) to the left ventricle (LV). LV dysfunction is suspected to contribute to adverse outcomes in EA/TVD. OBJECTIVE: We sought to examine global and segmental LV function in fetal EA/TVD with comparison to normal controls and PAIVS. We hypothesized that LV dysfunction in EA/TVD is associated with abnormal LV remodeling and interventricular mechanics. METHODS: We retrospectively identified 63 cases of fetal EA/TVD (40 with retrograde ductal flow) and 22 cases of PAIVS encountered from 2004 to 2015 and compared findings to 77 controls of comparable gestational age. We measured the combined CO and global LV function using two-dimensional, Doppler-derived, deformational (six-segmental vector velocity imaging) and dyssynchrony indices (DIs; SD of time to peak), and a novel global DI. RESULTS: EA/TVD fetuses demonstrated abnormal LV global systolic function with reduced ejection fraction, fractional area change, and CO, while in PAIVS we observed a normal ejection fraction, fractional area change, and CO. PAIVS, but not EA/TVD, demonstrated increased LV sphericity, suggestive of remodeling, and associated enhanced radial function in the third trimester. In contrast, while EA/TVD fetuses had normal LV segmental longitudinal strain, there was abnormal radial segmental deformation and LV dyssynchrony with increased SD of time to peak and DI. CONCLUSIONS: Fetal EA/TVD is associated with a lack of spherical remodeling and presence of mechanical dyssynchrony, which likely contribute to reduced CO and ejection fraction. Clinical monitoring of LV function is warranted in fetal EA/TVD. Further studies incorporating quantification of LV function into prediction models for adverse outcomes are required.

Assessment of Progressive Pathophysiology After Early Prenatal Diagnosis of the Ebstein Anomaly or Tricuspid Valve Dysplasia.

In fetuses with Ebstein anomaly or tricuspid valve dysplasia (EA/TVD), poor hemodynamic status is associated with worse neonatal outcome. It is not known whether EA/TVD fetuses with more favorable physiology earlier in gestation progress to more severe disease in the third trimester. We evaluated if echocardiographic indexes in EA/TVD fetuses presenting <24 weeks of gestation are reliable indicators of physiologic status later in pregnancy. This multicenter, retrospective study included 51 fetuses presenting at <24 weeks of gestation with EA/TVD and serial fetal echocardiograms ≥4 weeks apart. We designated the following as markers of poor outcome: absence of anterograde flow across the pulmonary valve, pulmonary valve regurgitation, cardiothoracic area ratio >0.48, left ventricular (LV) dysfunction, or tricuspid valve (TV) annulus Z-score >5.6. Median gestational age at diagnosis was 21 weeks (range, 18 to 24). Eighteen fetuses (35%) had no markers for poor hemodynamic status initially, whereas only 7 of these continued to have no markers of poor outcome in the third trimester. Nine of 27 fetuses (33%) with anterograde pulmonary blood flow on the first echocardiogram developed pulmonary atresia; 7 of 39 (18%) developed new pulmonary valve regurgitation. LV dysfunction was present in 2 (4%) patients at <24 weeks but in 14 (37%) later (p <0.001). The TV annulus Z-score and cardiothoracic area both increased from diagnosis to follow-up. In conclusion, progressive hemodynamic compromise was common in this cohort. Our study highlights that care must be taken in counseling before 24 weeks, as the absence of factors associated with poor outcome early in pregnancy may be falsely reassuring.

Echocardiographic assessment of Ebstein's anomaly.

Ebstein's anomaly is a complex congenital lesion which primarily involves the tricuspid valve. The tricuspid leaflets are tethered to varying degrees to the right ventricular free wall and the ventricular septum often resulting in significant tricuspid regurgitation and a small functioning right ventricular chamber. Although the septal leaflet originates normally at the right atrioventricular junction, the proximal portion is often completely tethered to the ventricular septum resulting in a misconception and erroneous statements in many publications that its attachment is apically displaced. Although two-dimensional echocardiography represents the primary modality for the diagnosis of this anomaly, three-dimensional echocardiography provides incremental value in characterizing the extent and severity of tethering of individual tricuspid valve leaflets. This information is useful in surgical decision making whether to repair or replace the tricuspid valve.

Review of the role of cardiovascular magnetic resonance in congenital heart disease, with a focus on right ventricle assessment.

Adult patients with congenital heart disease (ACHD) represent a growing population due to progress in management. Surgical procedures generally fall short of restoring entirely normal anatomical and functional relations. Further procedures can be needed and lifelong follow-up is required. The right ventricle (RV) plays an important role in congenital heart disease and cardiac magnetic resonance (CMR) imaging has become the imaging method of choice for its assessment. CMR can provide relatively accurate measurements of RV volume and function, and arterial flow, with additional anatomical information provided by three-dimensional contrast angiography and late gadolinium imaging of fibrosis. Here we focus our review on three categories of ACHD in which evaluation of the RV is important: repaired tetralogy of Fallot, the systemic RV and Ebstein anomaly. We demonstrate how CMR contributes to decision-making regarding the types and timings of interventions. A dedicated CMR service should be regarded as a necessary facility of a centre specializing in the care of ACHD patients.

An atypical assessment of Ebstein's anomaly in an 86-year-old man.

We present the echocardiographic analysis of an 86-year-old man affected by Ebstein's anomaly. In the natural history of this congenital disease only 5% of patients survive beyond the fifth decade. The patient presented severe right atrial dilatation and right heart failure, and he was referred to our institution for supraventricular tachycardia.

Cardiac magnetic resonance imaging and the assessment of ebstein anomaly in adults.

No published studies have evaluated the role of cardiac magnetic resonance (CMR) imaging for the assessment of Ebstein anomaly. Our objective was to evaluate the right heart characteristics in adults with unrepaired Ebstein anomaly using contemporary CMR imaging techniques. Consecutive patients with unrepaired Ebstein anomaly and complete CMR studies from 2004 to 2009 were identified (n = 32). Volumetric measurements were obtained from the short-axis and axial views, including assessment of the functional right ventricular (RV) end-diastolic volume (EDV) and end-systolic volume. The volume of the atrialized portion of the right ventricle in end-diastole was calculated as the difference between the total RVEDV and the functional RVEDV. The reproducibility of the measurements in the axial and short-axis views was determined within and between observers. The median value derived from the short-axis and axial views was 136 ml/m(2) (range 59 to 347) and 136 ml/m(2) (range 63 to 342) for the functional RVEDV, 153 ml/m(2) (range 64 to 441) and 154 ml/m(2) (range 67 to 436) for the total RVEDV, 49% (range 32% to 46%) and 50% (range 40% to 64%) for the functional RV ejection fraction, respectively. The axial measurements demonstrated lower intraobserver and interobserver variability than the short-axis approach for all values, with the exception of the intraobserver functional RVEDV and interobserver total RVEDV for which the limits of agreement and variance were not significantly different between the 2 views. In conclusion, measurements of right heart size and systolic function in patients with Ebstein anomaly can be reliably achieved using CMR imaging. Axial imaging appeared to provide more reproducible data than that obtained from the short-axis views.

Nongeometric quantitative assessment of right and left ventricular function: myocardial performance index in normal children and patients with Ebstein anomaly.

Assessment of ventricular systolic function has been based on the geometric models of ventricular shape. This study was designed to define normal values for a nongeometric myocardial performance index (MPI) in children and to evaluate the utility of MPI in congenital heart disease. The MPI measures the ratio of total time spent in isovolumic activity (isovolumic contraction time and isovolumic relaxation time) to the ejection time. The right ventricular (RV) and left ventricular (LV) MPI were measured in 152 normal children (ages 3 to 18 years) and 45 preoperative patients with Ebstein anomaly (age 1 week to 52 years). In normal children, the RV MPI was 0.32+/-0.03 and the LV MPI was 0.35+/-0.03. In the Ebstein group, both RV and LV MPI were abnormally increased compared with age-matched normal subjects (Ebstein group: RV MPI=0.49+/-0.12, LV MPI=0.42+/-0.09, P < .001). Increasing RV dysfunction was associated with progressively increasing (abnormal) values of RV MPI (P < .001). The myocardial performance index quantitatively reflects ventricular performance in patients with complex ventricular geometry (ie, Ebstein anomaly). In the absence of a geometric solution, this nongeometric index is particularly appealing for the assessment of RV or LV performance.

Assessment of right-to-left shunt flow in atrial septal defect by transesophageal color and pulsed Doppler echocardiography.

To investigate the clinical significance and problems of right-to-left (R-L) shunt flow dynamics in atrial septal defects, we performed transesophageal color and pulsed Doppler echocardiography in 30 patients with atrial septal defects of the ostium secundum type. The 30 patients consisted of 20 with a pulmonary artery systolic pressure of less than 40 mm Hg, four with a pressure of 40 to 60 mm Hg, three with a pressure of 90 mm Hg or more, two patients with pulmonic stenosis, and one patient with Ebstein's anomaly. R-L shunting was determined by the presence of a shunt flow signal across the defect during each cardiac cycle. The time of R-L shunt flow was compared with the various parameters obtained by echocardiography and cardiac catheterization. R-L shunt flow signals were detected at the following times: (1) at the onset of ventricular contraction or the closing phase of the tricuspid valve in five patients with isolated atrial septal defect. These patients showed an increase of mean right atrial pressure but had no severe pulmonary hypertension; (2) during ventricular systole in five of 26 patients with tricuspid regurgitation and one patient with Ebstein's anomaly. The tricuspid regurgitant signal was directed toward the ostium of the defect in three patients and was massive in the other patients; (3) during middiastole in three patients without pulmonary hypertension. These patients showed massive left-to-right shunt flow from end systole to early diastole; and (4) during atrial systole in three patients with severe pulmonary hypertension and two patients with pulmonic stenosis. The former, in particular, showed the aliasing signal as a high-speed shunt flow. In two of the three patients with severe pulmonary hypertension, R-L shunting continued from atrial systole to early ventricular systole and was also observed in early diastole. R-L shunt flow was detected in patients with atrial septal defects not only with pulmonary hypertension but also without pulmonary hypertension and was influenced by the right atrial pressure in the phase of tricuspid valve closing, the volume or direction of tricuspid regurgitation, rebound flow caused by massive left-to-right shunt flow, the grade of right ventricular distensibility or the complication of pulmonary hypertension, and complications with other cardiac anomalies. Thus R-L shunt flow in patients with atrial septal defects was detected easily by transesophageal color and pulsed Doppler echocardiography because of the high efficiency of this method for its detection.

Echocardiographic assessment of the right ventricle in Ebstein's anomaly: relation to clinical outcome.

Two-dimensional echocardiography was performed in 16 patients with Ebstein's anomaly to assess right ventricular anatomy and function in relation to clinical features and prognosis. Measurements of right ventricular anatomy and function were established in 10 normal subjects for comparison. Ten patients were in New York Heart Association functional class I, four in class II and one each in classes III and IV. Right ventricular morphology and the three tricuspid valve leaflets were assessed from right ventricular inflow tract and apical four chamber views. The anterior tricuspid leaflet was abnormal but not displaced in all patients; the septal and posterior leaflets were displaced in 14 (88%) and 11 (69%) patients respectively. The posterior leaflet was best visualized from the right ventricular inflow tract, and in two patients this view was required for the echocardiographic diagnosis of Ebstein's anomaly, based on displacement of the septal tricuspid valve leaflet. An index of right ventricular function, the fractional area contraction, was defined as the difference between the end-diastolic and the end-systolic area, normalized to the end-diastolic area. This index was calculated for both the proximal (atrialized) right ventricle and the total right ventricle. Total right ventricular end-diastolic area and fractional area contraction exceeded 95% confidence limits when compared with values in the normal group. During a median follow-up period of 4 years three patients died. They had severe right heart morphologic or functional abnormalities; two were in functional class III or IV and one was asymptomatic. None of the survivors had severe symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Two-dimensional echocardiographic spectrum of Ebstein's anomaly: detailed anatomic assessment.

This report details the two-dimensional echocardiographic assessment of 41 patients with Ebstein's anomaly. The anatomic spectrum of Ebstein's anomaly is correlated with surgical and autopsy observations in 66% of these patients. Morphologic abnormalities of the tricuspid valve and right heart structures were uniquely assessed by noninvasive two-dimensional echocardiographic examination. Features of the tricuspid valve that best related to decreased functional capacity were: 1) absence of the septal leaflet, and 2) pronounced tethering, restriction of motion and displacement of the anterior leaflet of the tricuspid valve. This 4 1/2 year experience suggests that two-dimensional echocardiography can replace angiography as the procedure of choice for diagnostic and morphologic assessment of Ebstein's anomaly. Cardiac catheterization is necessary only when specific hemodynamic questions or clinical inconsistencies exist.

Two-dimensional echocardiographic assessment of Ebstein's anomaly.

Nine patients with Ebstein's anomaly of the tricuspid valve were studied by two-dimensional echocardiography, using the standard long and short axis views as well as the apex four chamber view. With this latter view, the displacement of the tricuspid valve into the right ventricle was clearly seen in all nine cases of Ebstein's anomaly and was not noted in a control population. The severity of the tricuspid displacement was assessed by comparing the position of the mitral and tricuspid valves relative to the cardiac apex. The apex four chamber view allowed visualization of the atrioventricular (AV) ring simultaneously with the displaced tricuspid valve, and therefore the size of the "atrialized" right ventricle, true right ventricle and right atrium could be determined. These dimensions compared favorably with angiography.