5-Year Outcomes From the Harmony Native Outflow Tract Early Feasibility Study

4-Dimensional Right Ventricular Outflow Tract Segmentation to Evaluate Candidacy for Transcatheter Pulmonary Valve Replacement

Candidacy for transcatheter pulmonary valve replacement utilizing newer valve platforms is aided by industry-driven fit analyses. We report augmentation of this decision-making process by visualization of 4-dimensional cine imaging of patient-specific right ventricular outflow tract anatomy and a virtual valve model within a virtual reality platform.

Transcatheter Pulmonary Valve in Congenital Heart Disease

Over the last 2 decades, experience with transcatheter pulmonary valve replacement (TPVR) has grown significantly and has become an effective and reliable way of treating pulmonary valve regurgitation, right ventricular outflow (RVOT) obstruction, and dysfunctional bioprosthetic valves and conduits. With the introduction of self-expanding valves and prestents, dilated native RVOT can be addressed with the transcatheter approach. In this article, the authors review the current practices, technical challenges, and outcomes of TPVR.

Transcatheter-Based Interventions for Tetralogy of Fallot Across All Age Groups

Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. Palliative procedures, either surgical or transcatheter, aim to improve oxygen saturation, affording definitive procedures at a later stage. Transcatheter interventions have been used before and after surgical palliative or definitive repair in children and adults. This review aims to provide an overview of the different catheter-based interventions for TOF across all age groups, with an emphasis on palliative interventions, such as patent arterial duct stenting, right ventricular outflow tract stenting, or balloon pulmonary valvuloplasty in infants and children and transcatheter pulmonary valve replacement in adults with repaired TOF, including the available options for a large, dilated native right ventricular outflow tract.

Transcatheter Pulmonary Valve Replacement With the Harmony Valve in Patients Who Do Not Meet Recommended Oversizing Criteria on the Screening Perimeter Plot

BACKGROUND

Anatomic selection for Harmony valve implant is determined with the aid of a screening report and perimeter plot (PP) that depicts the perimeter-derived radius along the right ventricular outflow tract (RVOT) and projects device oversizing. The PP provides an estimation of suitability for implant, but its sensitivity as a screening method is unknown. This study was performed to describe anatomic features and outcomes in patients who underwent Harmony TPV25 implant despite a PP that predicted inadequate oversizing.

METHODS

We reviewed RVOT anatomic features and measurements in patients who underwent transcatheter pulmonary valve replacement with the Harmony TPV25 device despite a PP that predicted inadequate oversizing.

RESULTS

This study included 22 patients. There were no unsuccessful implants or adverse valve-related events. Anatomic features varied, but all patients fit into 1 of 3 anatomic types characterized by differences in RVOT dimensions. Type 1 patients (n=9) had a long RVOT with a choke point and a wide main pulmonary artery. Type 2 patients (n=6) had a short RVOT that was pyramidal in shape, with no choke point, and extensive main pulmonary artery lengthening/expansion during systole. Type 3 patients (n=7) had a short, bulbous main pulmonary artery with a choke point and an open pulmonary artery bifurcation.

CONCLUSIONS

Transcatheter pulmonary valve replacement with the Harmony valve is feasible in some patients whose PP fit analysis predicts inadequate oversizing. All cases in this series fit into 1 of 3 anatomic patterns, which are not identified in the screening report. Implanters must review cases individually to assess the feasibility of the implant.

Early Outcomes From a Multicenter Transcatheter Self-Expanding Pulmonary Valve Replacement Registry

BACKGROUND

Transcatheter pulmonary valve replacement (TPVR) with the self-expanding Harmony valve (Medtronic) is an emerging treatment for patients with native or surgically repaired right ventricular outflow tract (RVOT) pulmonary regurgitation (PR). Limited data are available since U.S. Food and Drug Administration approval in 2021.

OBJECTIVES

In this study, the authors sought to evaluate the safety and short-term effectiveness of self-expanding TPVR in a real-world experience.

METHODS

This was a multicenter registry study of consecutive patients with native RVOT PR who underwent TPVR through April 30, 2022, at 11 U.S.

CENTERS

The primary outcome was a composite of hemodynamic dysfunction (PR greater than mild and RVOT mean gradient >30 mm Hg) and RVOT reintervention.

RESULTS

A total of 243 patients underwent TPVR at a median age of 31 years (Q1-Q3: 19-45 years). Cardiac diagnoses were tetralogy of Fallot (71%), valvular pulmonary stenosis (21%), and other (8%). Acute technical success was achieved in all but 1 case. Procedural serious adverse events occurred in 4% of cases, with no device embolization or death. Hospital length of stay was 1 day in 86% of patients. Ventricular arrhythmia prompting treatment occurred in 19% of cases. At a median follow-up of 13 months (Q1-Q3: 8-19 months), 98% of patients had acceptable hemodynamic function. Estimated freedom from the composite clinical outcome was 99% at 1 year and 96% at 2 years. Freedom from TPVR-related endocarditis was 98% at 1 year. Five patients died from COVID-19 (n = 1), unknown causes (n = 2), and bloodstream infection (n = 2).

CONCLUSIONS

In this large multicenter real-world experience, short-term clinical and hemodynamic outcomes of self-expanding TPVR therapy were excellent. Ongoing follow-up of this cohort will provide important insights into long-term outcomes.

Bilateral Harmony™ valve placement in branch pulmonary arteries

While newer self-expanding pulmonic valves were primarily designed for larger right ventricular outflow tracks, there are instances where even larger anatomies cannot accommodate these devices. In this report, we describe the successful implantation of two Harmony™ valves in bilateral branch pulmonary arteries after exhausting other options.

2024 Statement from Asia expert operators on transcatheter pulmonary valve replacement

Transcatheter pulmonary valve replacement (TPVR), also known as percutaneous pulmonary valve implantation, refers to a minimally invasive technique that replaces the pulmonary valve by delivering an artificial pulmonary prosthesis through a catheter into the diseased pulmonary valve under the guidance of X-ray and/or echocardiogram while the heart is still beating not arrested. In recent years, TPVR has achieved remarkable progress in device development, evidence-based medicine proof and clinical experience. To update the knowledge of TPVR in a timely fashion, and according to the latest research and further facilitate the standardized and healthy development of TPVR in Asia, we have updated this consensus statement. After systematical review of the relevant literature with an in-depth analysis of eight main issues, we finally established eight core viewpoints, including indication recommendation, device selection, perioperative evaluation, procedure precautions, and prevention and treatment of complications.

Five-year follow-up after percutaneous pulmonary valve implantation using the Venus P-valve system for patients with pulmonary regurgitation and an enlarged native right ventricular outflow tract

BACKGROUND

Percutaneous pulmonary valve implantation (PPVI) with the self-expandable Venus P-valve system is a promising treatment for patients with pulmonary regurgitation (PR) and a native right ventricular outflow tract (RVOT). However, limited data is available regarding its midterm outcomes. This study assessed the midterm clinical and echocardiographic outcomes following Venus P-valve implantation.

METHODS

From 2013 to 2018, 55 patients with moderate or severe PR after surgical RVOT repair with a transannular or RVOT patch were consecutively enrolled from six hospitals in China. Five-year clinical and echocardiographic outcomes were collected and evaluated. The primary endpoint was a freedom from all-cause mortality and reintervention.

RESULTS

At 5 years, the primary endpoint was met for 96% of patients, corresponding to a freedom from all-cause mortality of 96% (95% confidence interval [CI]: 86%-99%) and freedom from reintervention of 98% (95% CI: 87%-100%). Endocarditis was reported in five patients (four patients within 1 year and one patient at 5 years) following PPVI. Transpulmonary gradient and stent orifice diameter remained stable compared to at discharge (p＞0.05). No paravalvular leak was reported while only 1 patient gradually increased to moderate PR during follow-up. Significant improvement of RV diameter and LVEF (p＜0.001) sustained over the 5-year follow-up, in consistent with remarked improved New York Heart Association(NYHA) functional class (p＜0.001).

CONCLUSION

The 5-year results of the China VenusP Study demonstrated the midterm benefits of Venus P-valve implantation in the management of patients with severe PR with an enlarged native RVOT by providing sustained symptomatic and hemodynamic improvement.

Current status of transcatheter intervention for complex right ventricular outflow tract abnormalities

Various transcatheter interventions for the right ventricular outflow tract (RVOT) have been introduced and developed in recent decades. Transcatheter pulmonary valve perforation was first introduced in the 1990s. Radiofrequency wire perforation has been the approach of choice for membranous pulmonary atresia in newborns, with high success rates, although complication rates remain relatively common. Stenting of the RVOT is a novel palliative treatment that may improve hemodynamics in neonatal patients with reduced pulmonary blood flow and RVOT obstruction. Whether this option is superior to other surgical palliative strategies or early primary repair of tetralogy of Fallot remains unclear. Transcatheter pulmonary valve replacement has been one of the biggest innovations in the last two decades. With the success of the Melody and SAPIEN valves, this technique has evolved into the gold standard therapy for RVOT abnormalities with excellent procedural safety and efficacy. Challenges remain in managing the wide heterogeneity of postoperative lesions seen in RVOT, and various technical modifications, such as pre-stenting, valve ring modification, or development of self-expanding systems, have been made. Recent large studies have revealed outcomes comparable to those of surgery, with less morbidity. Further experience and multicenter studies and registries to compare the outcomes of various strategies are necessary, with the ultimate goal of a single-step, minimally invasive approach offering the best longer-term anatomical and physiological results.

Catheter-based Interventions in Tetralogy of Fallot Across the Lifespan

Surgical treatment of tetralogy of Fallot (TOF) involves surgical relief of right ventricular outflow tract (RVOT) obstruction and closure of ventricular septal defect. However, some patients may require staged palliation before surgical repair. This traditionally was achieved only with surgery but recently evolved to include catheter-based techniques. RVOT dysfunction occurs inevitably after the surgical repair of TOF and, depending on the surgical approach, manifests as either progressive stenosis, regurgitation, or a combination of both. This predisposes the individual to repeated RVOT interventions with the attendant risks of multiple open-heart surgeries. The advent of transcatheter pulmonary valve replacement has reduced the operative burden, and the expansion of transcatheter pulmonary valve replacement device platforms has widened the type and size of RVOT anatomies that can be treated. This review will discuss the transcatheter therapies available throughout the lifespan of the patient with TOF.

Early results of Pulsta® transcatheter heart valve in patients with enlarged right ventricular outflow tract and severe pulmonary regurgitation due to transannular patch

OBJECTIVE

The purpose of this study is to assess the feasibility, effectivity, and safety of a novel self-expandable valve system, Pulsta® transcatheter heart valve in patients with tetralogy of fallot and severe pulmonary regurgitation after transannular patch repair.

BACKGROUND

Severe pulmonary regurgitation after tetralogy of fallot repair is a life-threatening problem and should be treated by pulmonary valve implantation. Although percutaneous pulmonary valve implantation has been ever increasingly used for this purpose, available balloon-expandable valves have limitations and cannot be used by most patients. Pulsta® transcatheter heart valve is a new self-expandable valve system and offers a new solution to be used in patients with different types of native right ventricular outflow tract geometry.

PATIENTS AND METHODS

Ten patients with severe regurgitation after tetralogy of fallot repair with a transannular patch have been enrolled in the study according to echocardiographic examination. MRI was used in asymptomatic patients to delineate the indication and the right ventricular outflow tract geometry. Pulsta® transcatheter heart valve implantation was performed in ten patients, and preprocedural, procedure, and 6 months follow-up findings of the patients were evaluated.

RESULTS

Pulsta® pulmonary valve implantation was performed in ten patients successfully without any severe complications. Valve functions were perfect in six of ten patients, while the others had insignificant regurgitation by echocardiographic examination at the end of 6 months follow-up.

CONCLUSIONS

This study showed that Pulsta® transcatheter heart valve is a feasible, effective, and safe method in the treatment of severe pulmonary regurgitation due to transannular patch repair in patients with tetralogy of fallot.

1-Year Outcomes in a Pooled Cohort of Harmony Transcatheter Pulmonary Valve Clinical Trial Participants

BACKGROUND

The Harmony transcatheter pulmonary valve (TPV) is the first U.S. Food and Drug Administration-approved device for severe pulmonary regurgitation (PR) in the native or surgically repaired right ventricular outflow tract (RVOT).

OBJECTIVES

One-year safety and effectiveness of the Harmony TPV were evaluated in patients from the Harmony Native Outflow Tract Early Feasibility Study, Harmony TPV Pivotal Study, and Continued Access Study, representing the largest cohort to date of Harmony TPV recipients.

METHODS

Eligible patients had severe PR by echocardiography or PR fraction ≥ 30% by cardiac magnetic resonance imaging and clinical indications for pulmonary valve replacement. The primary analysis included 87 patients who received a commercially available TPV22 (n = 42) or TPV25 (n = 45) device; 19 patients who received an early device iteration prior to its discontinuation were evaluated separately.

RESULTS

In the primary analysis, median patient age at treatment was 26 years (IQR: 18-37 years) in the TPV22 group and 29 years (IQR: 19-42 years) in the TPV25 group. At 1 year, there were no deaths; 98% of TPV22 and 91% of TPV25 patients were free from the composite of PR, stenosis, and reintervention (moderate or worse PR, mean RVOT gradient >40 mmHg, device-related RVOT reoperation, and catheter reintervention). Nonsustained ventricular tachycardia occurred in 16% of patients. Most patients had none/trace or mild PR (98% of TPV22 patients, 97% of TPV25 patients). Outcomes with the discontinued device are reported separately.

CONCLUSIONS

The Harmony TPV device demonstrated favorable clinical and hemodynamic outcomes across studies and valve types through 1 year. Further follow-up will continue to assess long-term valve performance and durability.

Self-Expanding Pulmonary Valves in 53 Patients With Native Repaired Right Ventricular Outflow Tracts

BACKGROUND

Self-expanding pulmonary valve grafts have been designed for percutaneous pulmonary valve implantation (PPVI) in patients with native repaired right ventricular (RV) outflow tracts (RVOTs). However, their efficacy, in terms of RV function and graft remodelling remain unclear.

METHODS

Patients with native RVOTs who received Venus P-valve (N = 15) or Pulsta valve (N = 38) implants between 2017 and 2022 were enrolled. We collected data on patient characteristics and cardiac catheterization parameters as well as imaging and laboratory data before, immediately after, and 6 to 12 months after PPVI and identified risk factors for RV dysfunction.

RESULTS

Valve implantation was successful in 98.1% of patients. The median duration of follow-up was 27.5 months. In the first 6 months after PPVI, all patients exhibited resolution of paradoxical septal motion and a significant reduction (P < 0.05) in RV volume, N-terminal pro-B-type natriuretic peptide levels, and valve eccentricity indices (-3.9%). Normalization of the RV ejection fraction (≥ 50%) was detected in only 9 patients (17.3%) and was independently associated with the RV end-diastolic volume index before PPVI (P = 0.03). Nine patients had residual or recurrent pulmonary regurgitation or paravalvular leak (graded as ≥ mild), which was associated with a larger eccentricity index (> 8%) and subsided by 12 months postimplantation.

CONCLUSIONS

We identified the risk factors likely to be associated with RV dysfunction and pulmonary regurgitation following PPVI in patients with native repaired RVOTs. RV volume-based patient selection is recommended for PPVI of a self-expanding pulmonary valve, along with monitoring of graft geometry.

Post-procedural structural heart CT imaging: TAVR, TMVR, and other interventions

Transcatheter valve replacement has experienced substantial growth in the past decade and this technique can now be used for any of the four heart valves. Transcatheter aortic valve replacement (TAVR) has overtaken surgical aortic valve replacement. Transcatheter mitral valve replacement (TMVR) is often performed in pre-existing valves or after prior valve repair, although numerous devices are undergoing trials for replacement of native valves. Transcatheter tricuspid valve replacement (TTVR) is similarly under active development. Lastly, transcatheter pulmonic valve replacement (TPVR) is most often used for revision treatment of congenital heart disease. Given the growth of these techniques, radiologists are increasingly called upon to interpret post-procedural imaging for these patients, particularly with CT. These cases will often arise unexpectedly and require detailed knowledge of potential post-procedural appearances. We review both normal and abnormal post-procedural findings on CT. Certain complications-device migration or embolization, paravalvular leak, or leaflet thrombosis-can occur after replacement of any valve. Other complications are specific to each type of valve, including coronary artery occlusion after TAVR, coronary artery compression after TPVR, or left ventricular outflow tract obstruction after TMVR. Finally, we review access-related complications, which are of particular concern due to the requirement of large-bore catheters for these procedures.

Single‐Center Experience of Hybrid Pulmonary Valve Replacement Using Left Anterior Thoracotomy With Pulmonary Artery Plication in Patients With Large Right Ventricular Outflow Tract

Background

Until recently, a large right ventricle outflow tract interfered with the feasibility of standard transcatheter pulmonary valve replacement (PVR). We are describing our experience using a hybrid approach for PVR using a left anterior thoracotomy approach to allow for plication of the main pulmonary artery followed by a transcatheter PVR using a Sapien S3 valve.

Methods and Results

This is a single‐center, retrospective review of patients who were evaluated to be appropriate for a hybrid PVR approach. The patients' demographics, procedure details, and follow‐up data were collected. Between May 2018 and April 2021, a total of 11 patients presented for hybrid transcatheter PVR. The median age and weight were 24 years (interquartile range, 19–43 years) and 81.8 kg (interquartile range, 69–91 kg), respectively. Nine out of 11 patients received a transcatheter PVR after main pulmonary artery plication. There were no procedurally related deaths. One major complication was encountered in which the valve was malpositioned requiring successful surgical PVR. Minor complications included acute kidney injury (n=1) and a broken rib (n=1). The median length of stay was 4 days (interquartile range, 2–4 days), with median follow‐up of 7 months (interquartile range, 3–18 months). A well‐functioning pulmonary valve was observed in all patients at the last follow‐up.

Conclusions

A hybrid approach using left anterior thoracotomy with pulmonary artery plication followed by transcatheter Sapien S3 PVR provides a less‐invasive option for patients with an enlarged right ventricular outflow tract. Preliminary results demonstrated this to be a safe option with good short‐term outcomes.

Right ventricular outflow tract anomalies: Neonatal interventions and outcomes

Right ventricular outflow tract (RVOT) anomalies comprise a wide spectrum of congenital heart disease, typically characterized by obstruction to flow from the right ventricle to pulmonary arteries. This review highlights important considerations surrounding management strategy as well as clinical outcomes for the neonate with RVOT anomaly, including: pulmonary atresia with intact ventricular septum, congenital pulmonary valve stenosis, tetralogy of Fallot, and Ebstein anomaly with anatomic or physiologic RVOT obstruction.

Transcatheter Device Therapy and the Integration of Advanced Imaging in Congenital Heart Disease

Transcatheter device intervention is now offered as first line therapy for many congenital heart defects (CHD) which were traditionally treated with cardiac surgery. While off-label use of devices is common and appropriate, a growing number of devices are now specifically designed and approved for use in CHD. Advanced imaging is now an integral part of interventional procedures including pre-procedure planning, intra-procedural guidance, and post-procedure monitoring. There is robust societal and industrial support for research and development of CHD-specific devices, and the regulatory framework at the national and international level is patient friendly. It is against this backdrop that we review transcatheter implantable devices for CHD, the role and integration of advanced imaging, and explore the current regulatory framework for device approval.