This 5-year-old girl had been experiencing dark discoloration of his lips and fingers, fast breathing, and easy fatigability since birth. Due to a lack of social awareness, the child was neglected. During an examination by a pediatrician at the age of 1 year, there was suspicion of a cardiac issue; however, the parents disregarded the child’s condition and did not pursue further medical follow-up. By the age of 3 years, the child began to exhibit more pronounced symptoms, including episodes of bluish discoloration of her hands, feet, and lips, and repeated respiratory infections. Despite this, his parents did not pursue medical care. Two years later, the patient’s condition further deteriorated, prompting her return to the hospital at the age of 5 years. On examination, she appeared underweight for his age, weighing 10 kg – only 75% of the expected weight – and was in respiratory distress. She exhibited both central and peripheral cyanosis, with an oxygen saturation of just 66% on room air. Physical assessment revealed a bulging anterior chest wall, and her apex beat was displaced to the 6th left intercostal space along the midclavicular line. A Grade 3/6 systolic murmur was detected at the tricuspid area, accompanied by a loud P2 at the left upper sternal border. Chest X-ray Figure 1 and echocardiography were performed. The chest X-ray showed cardiomegaly with left ventricle contour, the main pulmonary artery is not border forming, and there was increased pulmonary vascularity. Her echo Figure 2 showed unrestrictive conoventricular ventricular septal defect (VSD) with bidirectional shunting. Trileaflet truncal valve overriding the VSD. The left pulmonary artery (LPA) arises posteriorly and 13 mm distal to the truncal valve from the common trunk. The right pulmonary artery (RPA) likely originates from a collateral branch of the descending aorta. She underwent computed tomography (CT) of the cardiac, which showed LPA (white arrow) branching off from the common trunk supplying the left lung and RPA (orange arrow) branches off from the descending thoracic aorta and bifurcates into two branches supplying the right lung Figure 3.Figure 1: Chest X-ray showing cardiomegaly with left ventricle contour, the main pulmonary artery is not border forming, and there is increased pulmonary vascularityFigure 2: Echocardiography of truncus arteriosus: (a) Parasternal long-axis view (a) showing a large ventricular septal defect (VSD) (arrow) with override of trunk (t), (b and c) truncal valve overriding the VSD. The left pulmonary artery seen arising to the left and posteriorly from the common trunk. LA: Left atrium, LV: Left ventricle, RV: Right ventricleFigure 3: (a-d): CT cardiac which showing left pulmonary artery (white arrow) branching off from the common trunk supplying left lung and right pulmonary artery (orange arrow) branches off from descending thoracic aorta and bifurcates into two branches supplying right lungA diagnosis of persistent truncus arteriosus (PTA) type A3 was made. Unfortunately, due to the late presentation and severe pulmonary hypertension, the patient was deemed inoperable. The patient had severe pulmonary arterial hypertension with evidence of irreversible pulmonary vascular occlusive disease. Signs of inoperability in her were age > 1 year and resting systemic arterial oxygen saturation < 85%. The family was counseled regarding the poor prognosis, and the patient is currently on palliative medical therapy with sildenafil and diuretics. Follow-up is ongoing with supportive care. DISCUSSION PTA, also known as a common arterial trunk or common aorticopulmonary (AP) trunk, represents approximately 0.7% to 1.4% of all congenital heart defects in live-born infants, with an incidence rate of 0.03–0.056 per 1000 live births.1 The aortopulmonary septum develops as inward growths within the wall of the PTA, shifting position as they move from distal to proximal. This process results in a spiral-shaped septum that separates the truncus arteriosus into two equal vessels: the aorta and the pulmonary trunk. In cases of PTA, however, this septum fails to form, allowing both deoxygenated and oxygenated blood to mix and flow through a single common trunk.2 The cause of PTA is multifactorial and may be linked to conditions such as DiGeorge syndrome, a 22q11.2 deletion, maternal diabetes during pregnancy, and exposure to teratogens like retinoic acid. A nonrestrictive VSD is always present, allowing both ventricles to empty into the common trunk. Cyanosis in PTA is generally mild due to the high pulmonary blood flow and pressure. However, without timely treatment, elevated pulmonary vascular resistance (PVR) can develop early, leading to pulmonary hypertension, decreased lung perfusion, and worsening cyanosis. The Van Praagh classification system categorizes PTA based on the origin of the branch pulmonary arteries from the common trunk, the development of the aortic arch, and the presence of a patent ductus arteriosus.3 Type A1: The AP septum is partly formed, resulting in a partially separate main pulmonary artery Type A2: The AP septum is entirely absent, hence no discrete main pulmonary artery, with both pulmonary arterial branches arising directly from the common trunk Type A3: One central PA branch (usually right) arises from the proximal common trunk, while the opposite lung is supplied by a central branch PA arising from the ductus arteriosus or aortopulmonary collateral supply Type A4: The aortic isthmus displays hypoplasia, coarctation, atresia, or absence. The index patient was diagnosed with Type A3 PTA. Clinical presentation varies depending on the child’s age and PVR. In the first month of life, signs of heart failure and cyanosis are generally absent. As PVR decreases, symptoms of heart failure usually appear during the 2nd month. Common findings include a hyperdynamic precordium, cardiomegaly, and a single, loud second heart sound. Infants typically present with symptoms such as tachypnea, tachycardia, and failure to thrive. PTA can be assessed using multiple imaging techniques, each highlighting characteristic features of the condition. For example, a chest X-ray may reveal an enlarged cardiothoracic ratio, right-sided aortic arch in about 50% of cases, and signs of pulmonary overcirculation. An electrocardiogram often shows evidence of right ventricular hypertrophy. Echocardiography remains the primary diagnostic tool, typically identifying a large truncal artery overriding a VSD. Increasingly, CT is used alongside echocardiography to aid in detailed preoperative planning.4 While cardiac catheterization was once central to diagnosis, it is now mainly reserved for therapeutic interventions or for evaluating hemodynamics in older patients.5 It is no longer considered a first-line diagnostic method for newborns with PTA. It is advised that infants with PTA begin antiheart failure treatment within the 1st week of life. Surgical correction should ideally be performed within the 1st month, with the Rastelli procedure recommended before 3 months of age to prevent the onset of pulmonary vascular disease. During the operation, the VSD is closed, and the pulmonary artery is separated from the truncus. A homograft conduit is then used to establish a connection between the right ventricle and the pulmonary artery. While surgical outcomes are generally very good, the implanted conduits often develop stenosis or regurgitation as the child grows, necessitating future replacement. Surgery is contraindicated in patients with severe pulmonary arterial hypertension accompanied by irreversible pulmonary vascular occlusive disease. Indicators of inoperability include age over 1 year, resting systemic oxygen saturation below 85%, and the absence of cardiomegaly.6 Patients who are borderline operable due to advanced pulmonary vascular disease should be referred to a specialized center for further assessment. The decision to proceed with surgery should be individualized, considering the patient’s medical history, physical examination findings, and results from all relevant investigations. Key factors influencing long-term prognosis include persistent or worsening pulmonary hypertension, the need for conduit replacement, progressive regurgitation of the truncal or neoaortic valve, dilation or aneurysm of the aortic root, and recurrent aortic arch obstruction, particularly in Type A4 cases. Current data show perioperative mortality rates between 7% and 11%.7 Long-term survival has significantly improved over time, with studies reporting 10-year survival rates between 80% and 90%, and a 30-year survival rate of approximately 74%.8,9 Patients with PTA who do not receive surgical treatment generally have a poor prognosis. However, survival may be prolonged in individuals with associated pulmonary stenosis, as it can limit excessive pulmonary blood flow and reduce the risk of developing pulmonary vascular disease. Although rare, there are isolated reports of long-term survival without surgery, and most of these cases involve the presence of pulmonary stenosis.10 Causes of death may include metabolic acidosis, cardiac arrest, arrhythmias, impaired heart function, and failure of multiple organs. CONCLUSIONS PTA is a complex and life-threatening cyanotic congenital heart defect, with most affected children not surviving beyond their 1st year without intervention. However, this case illustrates that some patients may live longer, prompting important questions about the factors contributing to extended survival in a small subset compared to the majority. A critical insight from this case is that, even when survival is prolonged, medication alone cannot prevent the progressive decline in health and eventual mortality. Therefore, efforts must focus on improving access to and affordability of surgical treatment, especially in resource-limited settings. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the legal guardian has given her consent for images and other clinical information to be reported in the journal. The guardian understands that names and initials will not be published, and due efforts will be made to conceal patient identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Amit Mandal (Wed,) studied this question.
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