Pulmonary arterial hypertension leads to dyspnoea, fatigue, and oxygen desaturation, limiting activities of daily living and functional capacity. This study aimed to evaluate the impact of pulmonary arterial hypertension on activities of daily living performance, functional capacity, peripheral muscle strength, oxygen dynamics, and energy expenditure. Eighteen adolescents and young adults with pulmonary arterial hypertension (10 females, 8 males; age 9–30 years) and 15 healthy controls (10 males, 5 females; age 9–30 years) were included. Peripheral muscle strength was assessed using a handheld dynamometer, functional capacity via the 6-minute walk test, and muscle oxygenation through near-infrared spectroscopy. Lower-limb endurance was evaluated with the 1-minute sit-to-stand test and activities of daily living performance with the Glittre Activities of Daily Living test. Compared to controls, the pulmonary arterial hypertension group had significantly lower 6-minute walk test distance (441.9 m versus 636.9 m; p < 0.001), reduced sit-to-stand repetitions (28 versus 42.1; p < 0.001), weaker peripheral strength, and lower minimum muscle oxygen saturation (24.9% versus 51.8%; p < 0.001). Glittre Activities of Daily Living test duration was longer (143 s versus 105 s; p < 0.001), with greater oxygen desaturation (−13% versus −1%; p < 0.001), higher dyspnoea scores using modified Borg scale (5 versus 1; p < 0.001), and blunted heart rate response (ΔHR [change in heart rate]: 32 versus 64; p = 0.011). These findings demonstrate that pulmonary arterial hypertension significantly impairs both cardiopulmonary and peripheral muscle function. Protecting muscle health and improving functional capacity should be prioritised to enhance quality of life in this population.

Fulminant myocarditis is a life-threatening event that can present as cardiogenic shock. Human metapneumovirus (hMPV)–associated myocarditis is exceptionally uncommon, particularly in the pediatric population. Treatment may require mechanical ventilation, inotropic agents, vasopressors, and advanced life support systems. In this article, we report an 18-month-old previously healthy infant who presented with severe metabolic acidosis, elevated lactate, and profound biventricular systolic dysfunction secondary to hMPV infection. Despite mechanical ventilation, inotropic support, and initial immunomodulatory therapy with intravenous immunoglobulin, high-dose methylprednisolone, and anakinra, the patient’s clinical condition deteriorated rapidly, requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO) within the first 12 hours of admission. Given the absence of a patent foramen ovale and significant ventricular distention risk, surgical left ventricular decompression via a cannula inserted through the right upper pulmonary vein was performed. Hemoadsorption was additionally incorporated to mitigate hyperinflammation. Laboratory findings fulfilled macrophage activation syndrome criteria, and interferon-gamma blockade with emapalumab was initiated due to refractory cytokine storm physiology. Antioxidant therapy (nicotinamide adenine dinucleotide, coenzyme Q10, quercetin) was used as supportive treatment. Progressive improvement in ventricular function was observed under this comprehensive life support–based regimen. By day 12 of ECMO support, biventricular systolic function had normalized, and the patient was successfully weaned and discharged with full recovery. This case underscores the importance of early recognition, advanced immunomodulation, and effective ventricular unloading in managing fulminant hMPV myocarditis in children.

A patient post-Fontan palliation with a venous collateral unusually arising from the renal vein. Since renal vein oxygen saturations are relatively high, there was not systemic desaturation despite a right-to-left shunt.

Neonatal pulmonary artery thromboembolism is a rare, life-threatening condition associated with diagnostic and therapeutic challenges. Early diagnosis and intervention are critical to mitigate high morbidity and mortality. Our case underscores the importance of considering neonatal pulmonary artery thromboembolism in the differential diagnosis of a full-term neonate with unexplained acute respiratory distress and highlights a successful management approach in the absence of formal guidelines.

Primary pulmonary malignancies in single-ventricle patients are rare. Improved survival following surgical palliation has resulted in a growing Fontan population whose malignancy risk remains undefined. Standard oncologic approaches, especially for adenocarcinoma of the lung, need to be considered within the context of Fontan physiology. We present our management of primary lung adenocarcinoma in an adult with tricuspid atresia status postlateral tunnel Fontan palliation, highlighting considerations for this unique scenario.

Acute rheumatic fever is a systemic autoimmune disease resulting from an abnormal immune response to group A streptococcal pharyngitis. Cardiac findings are an important part of acute rheumatic fever and usually manifest as electrocardiographic abnormalities. The most common arrhythmia is first-degree atrioventricular block; however, in rare cases, complete atrioventricular block may occur. In this article, we present the case of an 11-year-old child who presented with complaints of knee pain and limited movement, in whom the diagnosis of acute rheumatic fever was suspected based on clinical, echocardiographic, and laboratory findings, and in whom complete atrioventricular block was detected on electrocardiographic. The patient’s electrocardiographic initially showed complete atrioventricular block, but with the treatment process, different levels of complete atrioventricular block were observed, and the electrocardiographic findings returned to normal. Particularly in patients who develop complete atrioventricular block, the response to treatment should be evaluated before making rapid decisions for pacemaker implantation, taking into account that the arrhythmia may be transient and can be corrected with medical treatment. This article emphasises that electrocardiographic abnormalities should not be ignored when diagnosing acute rheumatic fever and that patients should be evaluated in a holistic manner.

Syncope in children is commonly benign, yet rare cardiovascular anomalies may be causative. We present a child with recurrent syncope, ultimately diagnosed with an aorto-right atrial connection. Transcatheter closure was successfully performed with an Amplatzer Duct Occluder II. This case emphasizes considering aorto-atrial connections in pediatric syncope with continuous murmurs and highlights the efficacy of percutaneous closure.

While transcatheter atrial septal defect closure is routinely performed, acute biventricular failure is an extraordinary complication in adolescents, with only anecdotal reports in the literature. We present a 16-year-old male with borderline left ventricular systolic function and biventricular diastolic dysfunction who developed transient severe biventricular failure immediately following Amplatzer Septal Occluder (Abbott, Plymouth, MN, USA) deployment. Preprocedural echocardiography revealed right ventricular dilation, a D-shaped septum in diastole. Intraprocedural haemodynamic assessment demonstrated elevated right ventricular diastolic pressures (right ventricular minimal diastolic pressure: 11 mmHg; end-diastolic pressure: 17 mmHg). Haemodynamic collapse occurred within minutes of device release, necessitating emergent dopamine infusion and urgent coronary angiography to rule out device-related complications. Remarkably, ventricular function normalised within 2 hours, enabling extubation the same day. Reports of transient biventricular failure following atrial septal defect closure in adolescents without comorbidities are exceedingly rare, underscoring the critical role of preexisting diastolic dysfunction in precipitating acute decompensation. This case advocates for preprocedural balloon occlusion testing and vigilant haemodynamic monitoring in adolescents with impaired ventricular compliance to mitigate catastrophic outcomes.

Vitamin D deficiency is a common nutritional problem in exclusively breastfed infants. Dilated cardiomyopathy is a rare but potentially fatal complication of this condition. We describe a 15-month-old who presented with cardiogenic shock. Laboratory and radiographic findings were consistent with vitamin D deficiency. Metabolic parameters normalised within one week and echocardiography normalised by 19 months after supplementation. Although rare, severe vitamin D deficiency must be on the differential for young children presenting with new-onset dilated cardiomyopathy. Clinicians must maintain a high index of suspicion for vitamin D deficiency in at-risk populations to prevent potentially life-threatening complications.

The clinical case describes a 13-year-old boy with a history of transposition of the great arteries, ventricular septal defect, and pulmonary stenosis who underwent surgical correction at age 1 with the REV procedure and the Lecompte maneuver. At age 2, severe subaortic obstruction required reoperation for subaortic tunnel reconstruction, myectomy, and reimplantation. Due to severe right ventricular outflow tract dysfunction, a 19 mm No-React Injectable BioPulmonic prosthesis was implanted. At 12 years, the patient presented with reduced exercise tolerance. Echocardiography and cardiac catheterisation demonstrated severe stenosis and regurgitation of the pulmonary bioprosthesis, right ventricular dilatation and hypertrophy, and an increased right ventricular–pulmonary artery gradient with normal pulmonary artery pressures. The manuscript presents an in vitro test demonstrating that the No-React Injectable BioPulmonic prosthesis frame can be modified using high-pressure balloons to increase its true inner diameter. The patient subsequently underwent transcatheter valve-in-valve implantation of a 23 mm Sapien 3 following pre-dilation and frame modification of the 19 mm No-React Injectable BioPulmonic prosthesis with a 22 × 20 mm Atlas Gold balloon, achieving an favourable haemodynamic outcome. Post-implant pulmonary arteriography excluded any intra-perivalvular regurgitation. Post-procedure haemodynamic assessment showed a residual peak-to-peak gradient of 10 mmHg, with systolic right ventricular pressures below half of systemic pressure. At the 6-month follow-up after the procedure, the post-procedural peak echocardiographic gradient across the pulmonary prosthesis was measured at 28 mmHg, with no evidence of regurgitation. Short-term results have been optimal, which encourages the use of this strategy for the treatment of similar cases.

As staged palliative surgery for patients with hypoplastic left heart syndrome ages to greater than 50 years in practice, providers are increasingly faced with the challenges of managing patients with “failed Fontan” physiology. In this brief case report, we discuss different ways paediatric palliative care can support this population.

A 15-year-old female presented with exertional chest pain and near-syncope. Imaging revealed a large left sinus of Valsalva aneurysm compressing the left coronary artery. She underwent successful surgical repair. Intraoperative and pathologic findings confirmed Takayasu arteritis. This case highlights a rare aetiology of cardiac chest pain in adolescents and underscores the importance of evaluating for an underlying vasculitis when a sinus of Valsalva aneurysm is identified.

Levoatriocardinal vein is a rare venous anomaly occasionally presenting as a bidirectional shunt in structurally normal hearts. We describe two unique systemic connections of levoatriocardinal vein without intracardiac defects, one causing paradoxical embolism via the hemiazygos vein, and the other draining from the left jugular vein to the pulmonary vein, requiring surgical correction to preserve cerebral venous return.