Background: Patients with single-ventricle physiology represent a high-risk group for heart transplantation. Due to complex anatomical and physiological challenges, including multiple prior sternotomies, pulmonary artery abnormalities, and systemic consequences of altered circulation, they represent both a surgical and a clinical challenge. We aimed to analyze perioperative challenges, as well as early and long-term complications, in this specific group of patients. Methods: We performed a retrospective data analysis of a high-volume heart transplant center, focusing on patients with single-ventricle physiology who were scheduled for heart transplantation due to end-stage heart failure. We retrospectively analyzed the period from the beginning of the transplant program in November 1985 to the end of November 2024. Results: Among 1553 transplanted patients (adults and children), 29 were transplanted due to congenital heart disease (congenital valvular disease not included). In this group, nine patients were transplanted due to end-stage heart failure in the course of single-ventricle physiology. Age at transplantation ranged from 7 to 31 years (median, 17 years), and body weight ranged from 15 to 69 kg (median, 47.9 kg). All nine patients referred for heart transplantation presented with single-ventricle physiology. Their underlying congenital heart defects were heterogeneous and included hypoplastic left heart syndrome (HLHS), double-outlet left ventricle (DOLV), transposition of the great arteries (TGA) with associated ventricular septal defects (VSDs), atrial septal defects (ASDs), valvular abnormalities such as tricuspid and or pulmonary valve atresia or stenosis, systemic or atrioventricular valve regurgitation, and vascular abnormalities, including right-sided aortic arch, aortic coarctation, and pulmonary artery hypoplasia, stenosis, or occlusion, as well as associated pulmonary vascular abnormalities such as left pulmonary artery stenosis and MAPCAs. All patients had previously undergone staged palliative procedures, including Norwood, Hemi-Fontan, Fontan, bidirectional Glenn, modified Blalock-Taussig shunts, Bjork-Fontan, or pulmonary artery banding, often with repeated interventions such as balloon angioplasty, stent placement, or MAPCA closure. Extracardiac comorbidities were common and included coagulopathies, protein-losing enteropathy, hepatic dysfunction, and chronic venous insufficiency. Preoperative functional status was markedly impaired in all patients (NYHA III-IV, INTERMACS 3-4), with severely reduced exercise capacity and thrombotic events in several individuals. Perioperative transplant surgical strategies included femoral cannulation in four cases and standard aortic and caval cannulation in five cases. Pulmonary artery reconstruction was required in all patients. Extended donor pulmonary arteries were applied in eight cases, while a bifurcated Dacron prosthesis was utilized in one patient. Perioperative mortality was 33%, with three deaths attributed to bleeding and hemodynamic instability, while overall mortality was 44% including one late death unrelated to transplantation. Protein-losing enteropathy, although persistent in the immediate postoperative period, resolved in all surviving patients, underscoring the transformative impact of transplantation. Conclusions: These findings emphasize the importance of individualized surgical planning, extended donor pulmonary artery harvesting, and careful preoperative coordination. Heart transplantation remains a viable and life-extending option for selected single-ventricle patients, despite the significant technical and clinical challenges involved.

Recurrent idiopathic severe fetal structural anomalies present major challenges for reproductive decision-making and genetic counselling. A non-consanguineous healthy Estonian couple had experienced two electively terminated pregnancies at 12-13 weeks' gestation due to unexplained major fetal malformations and one early miscarriage. Their three pregnancies had resulted in unaffected newborns. Exome sequencing of fetal tissues from both terminated pregnancies identified a homozygous rare missense variant in MGRN1 (mahogunin ring finger 1), c.881G>A, p.(Arg294His) (Genome Aggregation Database V.4.1.0 allele frequency<8×10⁻⁵; no homozygotes reported in any population database). MGRN1 functions as an E3 ubiquitin ligase critical for protein homeostasis and developmental signalling. The detected substitution compromises a conserved residue within the RING (Really Interesting New Gene) finger domain. Cascade testing revealed that the parents and one unaffected child were heterozygous carriers, while two healthy siblings were homozygous for the reference allele. Both affected fetuses displayed congenital malformations closely mirroring prenatal phenotypes reported in Mgrn1 homozygous mutant mice, including cardiac malformations (ventricular septal defect, outflow tract malposition, pulmonary artery hypoplasia) and abnormal left-right axis patterning. These findings provide the first evidence implicating MGRN1 in human congenital disease and support its role in early embryonic patterning.

Pulmonary venous atresia (PVA) is a rare congenital anomaly of the pulmonary venous system, most commonly diagnosed in early childhood, with adult presentations being exceedingly uncommon. We report the case of a 43-year-old male who presented with progressive dyspnea in the context of a newly diagnosed laryngeal squamous cell carcinoma. Contrast-enhanced chest CT revealed complete right pulmonary venous atresia, associated right pulmonary artery hypoplasia, a right upper lobe pulmonary arteriovenous fistula, multiple mediastinal venous collaterals, and ipsilateral parenchymal changes. Pulmonary hypertension was subsequently confirmed by right heart catheterization. This case underscores the central role of CT in identifying unilateral PVA in adults, reviews the characteristic imaging features of this rare condition, and highlights the importance of including PVA in the differential diagnosis of unilateral pulmonary abnormalities.

Introduction: Congenital structural anomalies of the pulmonary artery in children, encompassing defects such as pulmonary atresia (PA), pulmonary stenosis (PS), pulmonary artery hypoplasia, and tetralogy of Fallot (ToF), pose significant challenges in pediatric cardiac surgery due to impaired blood flow in pulmonary circulation. Traditional options for conventional repair-including autologous materials such as the native pericardium and synthetic materials such as artificial patches-have limitations including a lack of growth potential and vulnerability to restenosis over time. ProxiCor® patches, based on the extracellular matrix (ECM), have emerged as biologically compatible substitutes capable of fostering tissue regeneration. The primary outcomes of this study were the safety (absence of patch-related complications such as restenosis, dilation, aneurysm, infection, or thrombosis) and feasibility (intraoperative handling and surgical success) of ProxiCor® for pulmonary artery and right ventricular outflow tract (RVOT) reconstruction in a single-center pediatric cohort. Secondary outcomes included mortality, postoperative complications (prolonged mechanical ventilation > 72 h, need for continuous renal replacement therapy (CRRT), and intensive care unit (ICU) and hospital stay), and qualitative echocardiographic assessment of vessel patency during follow-up. Patients and methods: A retrospective analysis was conducted in 25 consecutive pediatric patients who underwent pulmonary artery or RVOT reconstruction with ProxiCor® at the Department of Pediatric Cardiac Surgery in Poznań (Poland) between the years 2023 and 2024. Surgical techniques, clinical outcomes, and follow-up data were assessed using transthoracic echocardiography (TTE). Results: The median age was 224 (Q1-Q3: 124-362) days, and median weight was 4.2 (Q1-Q3: 2.8-8.5) kg. Procedures targeted repairs of the main pulmonary artery (MPA), right pulmonary artery (RPA), left pulmonary artery (LPA), and RVOT. Diagnoses included tetralogy of Fallot (ToF), pulmonary artery stenosis (PS), pulmonary atresia (PA), pulmonary artery hypoplasia, and anomalous left coronary artery from the pulmonary artery (ALCAPA). The mortality rate stood at 8% (2/25), stemming from multiorgan failure and hemorrhagic stroke, unrelated to the patch. Over a median observation period of 483 (Q1-Q3: 363-584) days, no patch-related complications (e.g., restenosis or dilation) arose. The median hospitalization time was 22 (Q1-Q3: 8.5-38.5) days. Conclusions: ProxiCor® ECM patches appear to be safe and feasible for use in pulmonary artery and RVOT reconstruction, with favorable early outcomes. However, the small cohort size, lack of a control group, and limited mid- to long-term echocardiographic data preclude definitive conclusions about long-term outcomes or comparative effectiveness.

The patient was diagnosed with unguarded tricuspid orifice (UGTO), functional pulmonary atresia, and left pulmonary artery hypoplasia. In view of the severe right ventricular dysfunction, the staged single ventricular palliation procedure was selected. The surgical procedure on Starnes operation and left pulmonary artery augmentation was performed one month after birth. As left pulmonary artery stenosis was diagnosed, secondly, the bidirectional cavopulmonary shunt with additional systemic to pulmonary shunt and intrapulmonary patch septation and left pulmonary artery augmentation with in-situ pericardium were performed. Despite the necessity for additional balloon dilation and surgical blunt dilation, the total cavopulmonary connection operation was ultimately performed, resulting in the successful implementation of staged single-ventricle palliation in conjunction with left pulmonary artery rehabilitation.