Acute cellular rejection (ACR) compromises graft function after heart transplantation (HTX). The purpose of this study was to describe systolic myocardial deformation in pediatric HTX and to determine whether it is impaired during ACR. Eighteen combined cardiac magnetic resonance imaging (CMR)/endomyocardial biopsy (EMBx) examinations were performed in 14 HTX patients (11 male, age 13.9 ± 4.7 years; 1.2 ± 1.3 years after HTX). Biventricular function and left ventricular (LV) circumferential strain, rotation, and torsion by myocardial tagging CMR were compared to 11 controls as well as between patients with and without clinically significant ACR. HTX patients showed mildly reduced biventricular systolic function when compared to controls [LV ejection fraction (EF): 55 ± 8% vs. 61 ± 3, p = 0.02; right ventricular (RV) EF: 48 ± 7% vs. 53 ± 6, p = 0.04]. Indexed LV mass was mildly increased in HTX patients (67 ± 14 g/m² vs. 55 ± 13, p = 0.03). LV myocardial deformation indices were all significantly reduced, expressed by global circumferential strain (−13.5 ± 2.3% vs. −19.1 ± 1.1%, p < 0.01), basal strain (−13.7 ± 3.0% vs. −17.5 ± 2.4%, p < 0.01), mid-ventricular strain (−13.4 ± 2.7% vs. −19.3 ± 2.2%, p < 0.01), apical strain (−13.5 ± 2.8% vs. −19.9 ± 2.0%, p < 0.01), basal rotation (−2.0 ± 2.1° vs. −5.0 ± 2.0°, p < 0.01), and torsion (6.1 ± 1.7° vs. 7.8 ± 1.1°, p < 0.01). EMBx demonstrated ACR grade 0 R in 3 HTX cases, ACR grade 1 R in 11 HTX cases and ACR grade 2 R in 4 HTX cases. When comparing clinically non-significant ACR (grades 0–1 R vs. ACR 2 R), basal rotation, and apical rotation were worse in ACR 2 R patients (−1.4 ± 1.8° vs. −4.2 ± 1.4°, p = 0.01 and 10.2 ± 2.9° vs. 2.8 ± 1.9°, p < 0.01, respectively). Pediatric HTX recipients demonstrate reduced biventricular systolic function and decreased myocardial contractility. Myocardial deformation indices by CMR may serve as non-invasive markers of graft function and, perhaps, rejection in pediatric HTX patients.

We describe an infant with an anomalous left coronary artery arising from the pulmonary trunk leading to myocardial ischaemia and development of an apical aneurysm of the left ventricle. Clinical presentation in general is based on myocardial hypoperfusion resulting in ischaemia and infarction. When presenting in infancy, however, then the features, as in our patient, may be tachypnea, dyspnea, failure to thrive and irritability, especially during feeding. Then, again as in our patient, it is possible to miss the definitive diagnosis, which is made by echocardiography and cardiac catheterization. Reimplantation of the anomalous left coronary artery into the aorta usually results in improvement of left ventricular function over time. In our patient, the myocardial infarction was complicated by formation of an aneurysm, and reimplantation alone was not sufficient to restore cardiac function. Resection of the aneurysm greatly improved the hemodynamics.

Although echocardiography remains the primary imaging modality for assessing Fontan palliation, a standardized systematic approach for evaluating the univentricular heart throughout the different stages of palliation has yet to be established. This document aims to provide a narrative review and practical guide for the echocardiographic assessment of the univentricular heart at various phases of Fontan palliation. Additional objectives include highlighting the potential of advanced three-dimensional (3D) and four-dimensional (4D) imaging modalities, as well as outlining a systematic strategy for detecting thromboembolic complications. We propose a sequential framework for echocardiographic evaluation, encompassing key anatomical and functional components of the univentricular heart. This includes the atrial septum and pulmonary veins, ventricular function, atrioventricular valve, aorta and neo-aorta, sub-aortic region, aortic arch, and pulmonary arteries. Furthermore, we detail the assessment of pulmonary blood supply at different stages of palliation, including the modified Blalock–Taussig–Thomas (mBTT) shunt, Sano conduit, Glenn procedure, and total cavo-pulmonary connection (TCPC). A comprehensive analysis of potential thrombus formation sites is provided, along with diagnostic pitfalls. Additionally, we outline methods for screening for extracardiac clots following Glenn and TCPC procedures. This document serves as a practical guide for the systematic echocardiographic evaluation of the univentricular heart across all stages of Fontan palliation, offering guidance for clinical practice. It also explores the capabilities of emerging 3D and 4D echocardiographic techniques in univentricular heart assessment and provides an in-depth review of thromboembolic complications, emphasizing key diagnostic challenges.