Background: Echocardiographic (echo) functional assessment of single systemic right ventricle (RV) lacks a reliable parameter and does not provide a substitute of volumetric ejection fraction (EF). RV volumes by 3D-echo are challenging and not widely used. Apical RV fractional area change (FAC) has shown some relation to CMR EF, but the strength of correlation has been suboptimal. Adding additional planes to apical FAC may improve this correlation. Our objective was to assess correlation of triplane FAC (apical, short-axis, and inflow-outflow) with CMR EF and to compare the tri- and single plane methods of measuring FAC to each other. Methods: Subjects with hypoplastic left heart syndrome (after superior or total cavopulmonary anastomosis) were prospectively recruited. CMR was performed and right ventricular ejection fraction was calculated. Transthoracic echo studies were performed close to the time of the CMR scan (median interval: 1 d). FAC was measured in apical 4-chamber view, parasternal short axis view at the mid ventricular level, and para-apical right ventricular inflow-outflow view. Triplane FAC was calculated by the average of the three FAC. Comparison was made between FAC and CMR-derived ejection fraction. Results: A total of 25 subjects underwent testing. Triplane FAC could not be assessed in 5, due to lack of optimal acoustic windows. Mean age was 10 ± 8 y (range 9 m to 24 y). Out of the uniplanar methods, apical FAC had the closest relationship to CMR EF. Triplane FAC showed even better correlation coefficient and R 2 values; although in this small group the difference did not reach significance. Results are summarized in the Table. Conclusion: In patients with single systemic RV, triplane FAC offers improved correlation with CMR EF relative to single plane evaluations. This approach may be useful if 3D echo is unavailable or of suboptimal quality and warrants further study.
Two‐Dimensional Measurement of Tricuspid Annular Plane Systolic Excursion in Children: Can It Substitute for an M‐Mode Assessment?
BackgroundTricuspid annular plane systolic excursion measured by M‐mode (MM‐TAPSE) has been validated as a marker of right ventricular systolic performance. A similar measurement by 2D imaging (2D‐TAPSE) can be obtained. We sought to determine the correlation and strength of agreement between MM‐TAPSE and 2D‐TAPSE in children.MethodsEchocardiographic studies performed for clinical indications were reviewed retrospectively. All consecutive subjects ≤18 years of age were included. The cohort was divided into those with normal echocardiographic findings and those with disorders affecting the right ventricle. Digitally recorded images were analyzed for both MM‐TAPSE and 2D‐TAPSE. Measurements of 2D‐TAPSE were made in an apical four‐chamber view, from the tricuspid valve annulus to a consistent point at the apex of the imaging sector at end‐diastole and end‐systole, with the difference representing the 2D‐TAPSE value.ResultsA total of 329 subjects (mean age 9.0 ± 6.1 years) met entry criteria. Correlation coefficient between MM‐TAPSE and 2D‐TAPSE was 0.90. Bland–Altman analysis showed agreement between the two methods to be within 1.2 ± 2.6 mm (mean percentage difference of 6.5%). About 1 mm difference between MM‐TAPSE and 2D‐TAPSE was consistently observed in all diagnostic subgroups, and across all age categories.ConclusionMM‐TAPSE and 2D‐TAPSE correlate strongly, with 2D‐TAPSE being consistently about 1 mm less than values obtained by the M‐mode technique. We conclude that 2D‐TAPSE can provide a reliable alternative to MM‐TAPSE to quantitatively measure right ventricular systolic function and may be especially useful in situations where retrospective comparisons are sought.