Introduction
Pulmonary valve dysfunction is a frequent long-term complication in patients with repaired Tetralogy of Fallot, often requiring reintervention during adolescence or early adulthood. Surgical pulmonary valve replacement has traditionally been the standard approach; however, according to the 2020 ESC Guidelines, in patients without a native right ventricular outflow tract, transcatheter pulmonary valve implantation is the preferred option when anatomically feasible.
While balloon-expandable valves have been widely used in transcatheter pulmonary valve implantation, they may be limited in non-cylindrical or distorted right ventricular outflow tract anatomies, where the risks of malapposition, paravalvular leak, or rupture are increased. Self-expanding valves, such as the Pulsta valve, offer a promising alternative due to their conformability and ability to anchor securely without the need for prestenting.
Here, we describe the first reported case in Vietnam of transcatheter pulmonary valve-in-valve implantation using a Pulsta valve in a young adult with repaired Tetralogy of Fallot and severe right ventricular outflow tract distortion, highlighting its feasibility, safety, and early clinical outcomes.
Case report
A 21-year-old Asian female with a history of repaired Tetralogy of Fallot was referred for routine follow-up. She had undergone complete surgical repair at 2.5 years of age, including ventricular septal defect patch closure, right ventricular outflow tract augmentation, and pectus excavatum correction. At 11 years old, she underwent redo open-heart surgery for severe pulmonary regurgitation, receiving a 23-mm Trifecta bioprosthetic valve (Abbott, St Paul, MN, USA) in the pulmonary position and pulmonary artery bifurcation reconstruction.
At the current evaluation, the patient was asymptomatic, with no exertional dyspnoea, chest pain, or syncope. Physical examination revealed a grade 3/6 systolic murmur at the left upper sternal border, normal blood pressure, heart rate, and oxygen saturation, without peripheral oedema or cyanosis.
Chest radiography revealed cardiomegaly, a dilated pulmonary artery trunk, left diaphragmatic paralysis, and mild scoliosis (Figure 1a). Electrocardiography showed sinus rhythm with complete right bundle branch block (QRS 162 ms) and right ventricular hypertrophy (Figure 1b). Holter monitoring demonstrated no significant arrhythmias. Transthoracic echocardiography demonstrated severe pulmonary stenosis (peak/mean gradients 71/41 mmHg), moderate regurgitation of the 23-mm Trifecta valve, a markedly dilated right ventricle with a right ventricular end-diastolic volume index of 167 mL/m2, reduced right ventricular ejection fraction of 46%, free wall strain of –20%, and an hourglass-shaped right ventricular outflow tract with distal diameter of 43 mm and a narrowed 22-mm annulus (Figure 1c–e). Cardiac MRI confirmed right ventricular dilation (right ventricular end-diastolic volume index 176 mL/m2), dysfunction (right ventricular ejection fraction 41%), and provided detailed right ventricular outflow tract anatomy and measurements used for device sizing (Figure 1f).
( a ) Chest radiography showing cardiomegaly, dilated pulmonary artery trunk, left diaphragmatic paralysis, and mild scoliosis. ( b ) Electrocardiography showing sinus rhythm, complete right bundle branch block (QRS 162 ms), and right ventricular hypertrophy. ( c – e ) Transthoracic echocardiography showing the 23-mm trifecta valve, dilated and dysfunctional right ventricle, and hourglass-shaped right ventricular outflow tract. ( f ) Cardiac MRI assessing RVOT size for device selection.
Given the severe right ventricular dilation, reduced function, and degenerated bioprosthetic valve, the multidisciplinary heart team recommended transcatheter pulmonary valve implantation to avoid the risks of a third surgical procedure.
Under general anaesthesia, femoral artery and vein access were obtained. Right heart catheterisation confirmed elevated right ventricular systolic pressure (72 mmHg). Angiography demonstrated a narrowed annulus (22 mm) and distal right ventricular outflow tract dilation (“hourglass” configuration) (Figure 2a).
( a ) Pulmonary angiography showing hourglass-shaped RVOT with the trifecta bioprosthetic valve at the waist. ( b ) High-pressure balloon dilatation of the pulmonary valve and low-pressure balloon sizing to assess adequate expansion. ( c , d ) Deployment of a 24-mm pulsta valve (TaeWoong Medical, Gimpo, Republic of Korea) using an 18-fr delivery system. ( e , f ) Post-implantation assessment showing good valve expansion and angiographic confirmation of no intra- or para-valvular leak.
The degenerated bioprosthetic valve was dilated using a Atlas 22 × 40 mm high-pressure balloon inflated to 20 atmospheres. Sizing with a 24-mm Amplatzer sizing balloon (Abbott, Plymouth, MN, USA) confirmed full expansion after fracture, ensuring suitability for anchoring a self-expanding Pulsta valve (Figure 2b).
A 24-mm diameter, 31 mm length Pulsta valve (TaeWoong Medical, Gimpo, Republic of Korea) was delivered using an 18-Fr system and deployed without prestenting (Figure 2c,d). Final angiography confirmed excellent positioning, no paravalvular leak, and complete elimination of regurgitation (Figure 2e,f). The patient was discharged on postoperative day two on aspirin.
At six months, she reported improved exercise capacity without symptoms. Echocardiography showed a well-functioning valve (peak gradient 20.3 mmHg, mean gradient 10.2 mmHg, trace regurgitation), and right ventricular dimensions had normalised. Follow-up cardiac MRI confirmed improved right ventricular volumes and function, with right ventricular end-diastolic volume index 95 mL/m2 and right ventricular ejection fraction 48%, without complications.
Discussion
Bioprosthetic pulmonary valve degeneration is a common long-term complication after surgical repair of Tetralogy of Fallot, particularly in patients who underwent valve replacement during childhood or adolescence. Timely pulmonary valve replacement is essential to prevent irreversible right ventricular dysfunction, arrhythmias, and sudden cardiac death. Reference McElhinney, Hellenbrand and Zahn1,Reference Geva2
According to the 2020 ESC Guidelines, in patients without a native right ventricular outflow tract, transcatheter pulmonary valve implantation is the preferred option if anatomically feasible. Reference Baumgartner, De Backer and Babu-Narayan3 Balloon-expandable valves have shown excellent outcomes, particularly in cylindrical conduits, but they carry risks of malapposition, paravalvular leak, or rupture in irregular or heavily calcified anatomies. Reference Suradi and Hijazi4
Self-expanding valves, such as the Pulsta valve, provide an alternative because of their ability to conform to complex right ventricular outflow tract geometries without prestenting. Reference Kim, Kwon and Lim5,Reference Lee, Kim, Kim, Jang, Choi and Kang6 However, in this case, the hourglass-shaped right ventricular outflow tract was not the decisive factor for choosing an self-expanding valve, as the rigid metallic bioprosthetic ring already ensured anchoring, eliminating the need for prestenting. Theoretically, balloon-expandable valves offer superior radial force, particularly when overcoming heavy calcification. The main reason for selecting an self-expanding valve here was its potential advantage of providing a larger inner lumen compared with a balloon-expandable valve, assuming successful implantation.
Importantly, while self-expanding valves have been increasingly used in native right ventricular outflow tract settings, only a few published cases have described self-expanding valves, such as the Venus P-valve, being used in valve-in-valve transcatheter pulmonary valve implantation. Reference Li, Pan, Wang and He7 After thorough literature review, we found no previously published cases specifically reporting Pulsta valve implantation in a valve-in-valve pulmonary position, underscoring the novelty and clinical importance of this report.
Multimodal imaging, including four-dimensional echocardiography, cardiac MRI, and intra-procedural balloon sizing, played a critical role in procedural planning and valve selection. Reference Geva2,Reference Puchalski, Williams, Askovich, Minich, Mart and Tani8 Furthermore, early intervention in asymptomatic patients with objective signs of right ventricular dilation and dysfunction can promote favourable reverse remodelling and improved clinical outcomes. Reference Baumgartner, De Backer and Babu-Narayan3 This case highlights the expanding role of self-expanding valves in CHD interventions and reinforces the importance of individualised procedural strategies and multidisciplinary team decision-making.
Conclusion
This case demonstrates the feasibility and early success of using a self-expanding Pulsta valve in a valve-in-valve pulmonary position, representing the first reported experience of its kind. It highlights the importance of individualised device selection, advanced imaging, and multidisciplinary team decision-making in the management of complex CHD interventions.
