Longitudinal evaluation of allograft diastolic function in paediatric heart transplant recipients is important for early detection of acute rejection, cardiac allograft vasculopathy, and graft dysfunction. Mean diastolic right atrial and pulmonary capillary wedge pressures obtained at catheterisation are the reference standards for assessment. Echocardiography is non-invasive and more suitable for serial surveillance, but individual parameters have lacked accuracy. This study aimed to identify covariates of post-transplant mean right atrial and pulmonary capillary wedge pressures, including B-type natriuretic peptide and certain echocardiographic parameters.

A retrospective review of 143 scheduled cardiac catheterisations and echocardiograms from 56 paediatric recipients transplanted from 2007 to 2011 was performed. Samples with rejection were excluded. Univariate and multivariate linear regression models using backward selection were applied to a database consisting of B-type natriuretic peptide, haemodynamic, and echocardiographic data.

Ln B-type natriuretic peptide, heart rate z-score, left ventricular end-diastolic dimension z-score, mitral E/e’, and percent interventricular septal thickening in systole were independently associated with mean right atrial pressure. Ln B-type natriuretic peptide, heart rate z-score, left ventricular end-diastolic dimension z-score, left ventricular mass (observed/predicted), and mitral E/e’ were independently associated with mean pulmonary capillary wedge pressure. Covariates of B-type natriuretic peptide included mean pulmonary artery and pulmonary capillary wedge pressures, height, haemoglobin, fractional shortening, percent interventricular septal thickening in systole, and pulmonary vascular resistance index.

B-type natriuretic peptide and echocardiographic indices of diastolic function were independently related to post-transplant mean right atrial and pulmonary capillary wedge pressures in paediatric heart transplant recipients without rejection.

Ventriculo-ventricular interactions are known to exist, though not well quantified. We hypothesised that the ventricular–vascular coupling ratio assessed by cardiovascular MRI would provide insight into this relationship. We also sought to compare MRI-derived ventricular–vascular coupling ratio to echocardiography and patient outcomes.

Children with cardiac disease and biventricular physiology were included. Sanz’s and Bullet methods were used to calculate ventricular–vascular coupling ratio by MRI and echocardiography, respectively. Subgroup analysis was performed for right and left heart diseases. Univariate and multivariate regressions were performed to determine associations with outcomes.

A total of 55 patients (age 14.3 ± 2.5 years) were included. Biventricular ventricular–vascular coupling ratio by MRI correlated with each other (r = 0.41; p = 0.003), with respect to ventricle’s ejection fraction (r = −0.76 to −0.88; p < 0.001) and other ventricle’s ejection fraction (r = −0.42 to −0.47; p < 0.01). However, biventricular ejection fraction had only weak correlation with each other (r = 0.31; p = 0.02). Echo underestimated ventricular–vascular coupling ratio for the left ventricle (p < 0.001) with modest correlation to MRI-derived ventricular–vascular coupling ratio (r = 0.43; p = 0.002). There seems to be a weak correlation between uncoupled right ventricular–vascular coupling ratio with the need for intervention and performance on exercise testing (r = 0.33; p = 0.02).

MRI-derived biventricular ventricular–vascular coupling ratio provides a better estimate of ventriculo-ventricular interaction in children and adolescents with CHD. These associations are stronger than traditional parameters and applicable to right and left heart conditions.

The Pediatric Heart Network Normal Echocardiogram Database Study had unanticipated challenges. We sought to describe these challenges and lessons learned to improve the design of future studies.

Challenges were divided into three categories: enrolment, echocardiographic imaging, and protocol violations. Memoranda, Core Lab reports, and adjudication logs were reviewed. A centre-level questionnaire provided information regarding local processes for data collection. Descriptive statistics were used, and chi-square tests determined differences in imaging quality.

For the 19 participating centres, challenges with enrolment included variations in Institutional Review Board definitions of “retrospective” eligibility, overestimation of non-White participants, centre categorisation of Hispanic participants that differed from National Institutes of Health definitions, and exclusion of potential participants due to missing demographic data. Institutional Review Board amendments resolved many of these challenges. There was an unanticipated burden imposed on centres due to high numbers of echocardiograms that were reviewed but failed to meet submission criteria. Additionally, image transfer software malfunctions delayed Core Lab image review and feedback. Between the early and late study periods, the proportion of unacceptable echocardiograms submitted to the Core Lab decreased (14 versus 7%, p < 0.01). Most protocol violations were from eligibility violations and inadvertent protected health information disclosure (overall 2.5%). Adjudication committee reviews led to protocol changes.

Numerous challenges encountered during the Normal Echocardiogram Database Study prolonged study enrolment. The retrospective design and flaws in image transfer software were key impediments to study completion and should be considered when designing future studies collecting echocardiographic images as a primary outcome.

In CHD, three-dimensional strain analysis may overcome limitations of Doppler and two-dimensional strain of the left ventricle. The aims of this study were to evaluate feasibility and reproducibility of three-dimensional longitudinal, circumferential, and radial systolic strain by three-dimensional speckle-tracking echocardiography compared with two-dimensional echocardiography.

Patients with CHD, biventricular circulation with a systemic left ventricle, and who had two- and three-dimensional imaging performed on the same day from 2010 to 2014 were included. Quantitative two- and three-dimensional strain analyses were performed (two-dimensional cardiac performance analysis version 1.2 and four-dimensional left ventricular analysis version 3.1). Intra- and inter-observer variabilities were calculated on 25 studies.

A total of 30 patients, including 19 (61%) males, with a median age of 3.6 years (0.1–22 years) were included. The mean fractional shortening was 34.6±5.3%, and the mean ejection fraction was 62.0±6.4%. Measurement of two- and three-dimensional strain was feasible in >95% of segments. Good correlation was observed between longitudinal and circumferential strain (r=0.92, p⩽0.001 and r=0.87, p⩽0.001), but not radial strain (r=0.29, p=0.2). Intra- and inter-observer agreements were better for three-dimensional compared with two-dimensional strain, and better for both two- and three-dimensional longitudinal and circumferential strains compared with radial strain.

Left ventricular three-dimensional strain analysis is feasible in children with CHD. The reproducibility of longitudinal and circumferential strain by three-dimensional analyses is better. Further longitudinal studies are warranted for the potential clinical application of this new technology.