Introduction
Pulmonary arterial hypertension is a progressive, life-threatening disease that may lead to severe right ventricular pressure overload and failure despite targeted therapy. In selected high-risk children, decompressive interventions such as atrial septostomy or reverse Potts shunt may be considered, whereas ventricular-level decompression remains rarely reported. Reference Ivy, Rosenzweig and Abman1–Reference Sandoval3
We describe de novo transcatheter creation of a ventricular septal shunt through an intact muscular septum using a covered stent in a child with end-stage suprasystemic pulmonary arterial hypertension.
Case report
A 7-year-old girl weighing 26 kg was referred with progressive exertional dyspnoea and fatigue. Two siblings had died from pulmonary arterial hypertension, but genetic testing for heritable pulmonary arterial hypertension was negative. Echocardiography showed marked right heart dilation, right ventricular hypertrophy, interventricular septal flattening, and an estimated right ventricular systolic pressure of 95 mmHg (Figure 1a–c). Cardiac catheterisation showed pulmonary arterial pressure of 85/46 mmHg (mean 61), systemic pressure of 90/48 mmHg (mean 62), and pulmonary vascular resistance of 26 Wood units. Bosentan and sildenafil were initiated.
Transthoracic echocardiographic images before and after transcatheter ventricular septal shunt creation. ( a – b ) Apical four-chamber views prior to the procedure demonstrating marked dilation of the RA and RV, interventricular septal flattening with LV compression, and severe tricuspid regurgitation on colour Doppler imaging. ( c ) Colour Doppler image demonstrating right-to-left shunting through the previously created atrial septal communication. ( d ) Post-procedural apical four-chamber view showing the implanted septal stent (arrow) with right-to-left ventricular flow across the stent. ( e ) Modified parasternal long-axis view demonstrating the stent (arrow) within the interventricular septum with colour Doppler evidence of right-to-left shunting. ( f ) Follow-up apical four-chamber image demonstrating the septal stent (arrow) and associated pericardial effusion (star).
At 9 years of age, worsening right ventricular failure prompted atrial septostomy. Pulmonary arterial pressure was 105/65 mmHg (mean 77), systemic pressure 75/41 mmHg (mean 55), and right atrial pressure 20 mmHg. After septostomy, right atrial pressure decreased to 18 mmHg, and systemic saturation decreased from 95% to 88%. A 7-mm atrial communication remained, and inhaled iloprost was added. Clinical stabilisation persisted for approximately three years.
At 12 years of age, the patient deteriorated despite maximal therapy. Echocardiography showed severe right ventricular dilation, reduced systolic function, marked septal deviation, and suprasystemic right ventricular pressure. Parenteral prostacyclin therapy was not initiated because of concerns regarding adherence, and lung transplantation was not available under national eligibility criteria. Reverse Potts shunt was considered, but imaging showed no suitable contact zone between the left pulmonary artery and descending aorta. Transcatheter ventricular septal shunt creation was therefore selected as a rescue option.
Under general anaesthesia and transesophageal echocardiographic and fluoroscopic guidance, a mid-to-apical muscular septal target remote from the valves was selected. A Brockenbrough needle was advanced from the right ventricle across the intact interventricular septum into the left ventricle. The tract was sequentially dilated with 6-, 10-, and 12-mm balloons. A 14 × 38 mm covered BeGraft stent was then deployed across the septum, establishing right-to-left ventricular shunting without contrast extravasation (Figure 2a–e).
Angiographic images illustrating the stepwise process of transcatheter ventricular septal shunt creation. ( a ) Left ventriculography delineates the target mid-to-apical muscular interventricular septum, with an 8.5-F steerable sheath (arrow) positioned at the intended site. ( b ) Septal perforation is performed using a Brockenbrough transseptal needle (arrow). ( c ) Balloon dilation (star) establishes the newly created ventricular communication. ( d – e ) A covered stent (arrow) is deployed across the interventricular septum; subsequent contrast injection confirms stent patency and right-to-left ventricular shunting. ( f ) The previously created atrial septal defect is closed with an 11-mm Amplatzer Septal Occluder. RA = right atrium; RV = right ventricle; LA = left atrium; LV = left ventricle.
Immediate intraprocedural measurements showed an increase in mean aortic pressure from 65 to 80 mmHg, while pulmonary arterial pressure remained suprasystemic at 115/60 mmHg, pulmonary vascular resistance decreased modestly from 28.15 to 25.93 Wood units, and the pulmonary-to-systemic vascular resistance ratio decreased from 2.37 to 1.85. Oxygen saturation was 85%, and no further enlargement was performed. Echocardiography confirmed unobstructed shunt flow and no immediate pericardial effusion (Figure 1d–e).
On post-procedure day 4, a significant pericardial effusion developed, and pericardiocentesis was performed (Figure 1f). The fluid was serous and exudative. CT was subsequently obtained to exclude ventricular perforation or stent-related myocardial injury. Persistent hypoxaemia in the setting of combined atrial- and ventricular-level shunting prompted temporary balloon occlusion of the atrial communication. Right atrial pressure remained 18 mmHg, and the defect was closed with an 11-mm Amplatzer Septal Occluder, increasing systemic oxygen saturation to approximately 88–90% (Figure 2f).
On post-procedure day 6, persistent effusion and clinical instability raised concern for a structural complication. Surgical exploration showed no myocardial perforation, active bleeding, or stent malposition. Despite intensive care, progressive biventricular dysfunction, refractory hypoxaemia, and metabolic acidosis developed, and the patient died on post-procedure day 8.
Discussion
Transcatheter ventricular septal defect creation has previously been reported in children with severe pulmonary hypertension, including a three-patient series by Chartan et al. 4 Other reports have largely involved enlargement of a pre-existing restrictive ventricular septal defect or recreation of a communication through a surgical patch. Reference Sivakumar5–Reference Lin, Huddleston and Balzer7 In contrast, the present case involved de novo Brockenbrough needle puncture of previously intact muscular myocardium, followed by balloon dilation and covered-stent implantation. This anatomical distinction may carry a different procedural risk profile and is central to the novelty of this report.
The haemodynamic response was limited. Although right-to-left ventricular shunting was established, pulmonary arterial pressure remained suprasystemic, pulmonary vascular resistance decreased only modestly, and systemic desaturation occurred. The optimal management and timing of closure of a concomitant atrial communication remain uncertain and should be individualised according to the haemodynamic response. Given the limited available evidence, whether staged enlargement improves haemodynamic outcomes or procedural safety remains uncertain. Reference Sandoval3,Reference Sivakumar5,Reference Baruteau, Serraf and Lévy8,Reference Barst9
The post-procedure course was complicated by persistent pericardial effusion requiring pericardiocentesis and surgical exploration, representing a serious adverse event temporally associated with the intervention. Post-cardiac injury syndrome was clinically suspected; Reference Malik, Zaidi, Rana, Haider and Tahir10,Reference Platek, Persits, Khayata, Badwan, El Roumi and Klein11 however, the aetiology remained uncertain, and a procedure-related mechanical cause could not be definitively excluded. Septal puncture, balloon dilation, or stent implantation may have contributed to myocardial injury, while patients with suprasystemic pulmonary arterial hypertension may be particularly vulnerable because of extreme intracardiac pressures, myocardial hypertrophy, and limited cardiac reserve.
This case highlights the limitations and potential risks of transcatheter ventricular septal shunt creation in end-stage suprasystemic pulmonary arterial hypertension. Careful patient selection, multidisciplinary planning, and individualised risk assessment are essential when considering this approach.
Ethical standards
The authors assert that all procedures contributing to this report complied with the ethical standards of the relevant institutional guidelines and with the Declaration of Helsinki.
