Relationships Among Conduit Type, Pre-Stenting, and Outcomes in Patients Undergoing Transcatheter Pulmonary Valve Replacement in the Prospective North American and European Melody Valve Trials

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.

Standardized Bench Test Evaluation of Biomechanical Characteristics of Stents Used in Right Ventricular Outflow Tract Revalvulation

PURPOSE

Pre-stenting of the right ventricular outflow tract (RVOT) is commonly performed before percutaneous pulmonary valve implantation (PPVI), to relieve obstruction, prevent valved stent fractures, and provide a landing zone. This study aimed to evaluate the biomechanical characteristics of the stents currently used to perform pre-stenting of the RVOT.

METHODS

We assessed five commercially available stents: Cheatham-Platinum Stent ("CP Stent"), AndraStent XL, AndraStent XXL, Optimus XL, and Optimus XXL. Following stent deployment at nominal pressure, radial and longitudinal elastic recoils and radial resistance were measured. The bending stiffness of the stents crimped onto the balloons was also evaluated.

RESULTS

Three samples were tested for each stent. Our study showed no significant difference between the stent platforms in terms of radial elastic recoil, which was relatively low (< 10%). The longitudinal elastic recoil was also low for all the devices (< 5%). Significant differences were observed in radial resistance (P < 0.001). CP Stent and AndraStent XL exhibited the highest radial resistances. The bending stiffnesses of the stents crimped on their balloons were significantly different (P < 0.00001). Optimus XL and XXL were more flexible than the other stents.

CONCLUSION

This study highlights the significant differences between the stents currently used in RVOT pre-stenting. Stents with good radial resistance are preferred, especially for calcified vessels, and flexibility is crucial for tortuous vessels. We proposed an algorithm for selecting the most suitable stent according to the need for radial force and flexibility, which will help inform clinicians considering RVOT revalvulation.

Outcomes of transcatheter pulmonary SAPIEN 3 valve implantation: an international registry

BACKGROUND AND AIMS

Transcatheter pulmonary valve implantation (TPVI) is indicated to treat right-ventricular outflow tract (RVOT) dysfunction related to congenital heart disease (CHD). Outcomes of TPVI with the SAPIEN 3 valve that are insufficiently documented were investigated in the EUROPULMS3 registry of SAPIEN 3-TPVI.

METHODS

Patient-related, procedural, and follow-up outcome data were retrospectively assessed in this observational cohort from 35 centres in 15 countries.

RESULTS

Data for 840 consecutive patients treated in 2014-2021 at a median age of 29.2 (19.0-41.6) years were obtained. The most common diagnosis was conotruncal defect (70.5%), with a native or patched RVOT in 50.7% of all patients. Valve sizes were 20, 23, 26, and 29 mm in 0.4%, 25.5%, 32.1%, and 42.0% of patients, respectively. Valve implantation was successful in 98.5% [95% confidence interval (CI), 97.4%-99.2%] of patients. Median follow-up was 20.3 (7.1-38.4) months. Eight patients experienced infective endocarditis; 11 required pulmonary valve replacement, with a lower incidence for larger valves (P = .009), and four experienced pulmonary valve thrombosis, including one who died and three who recovered with anticoagulation. Cumulative incidences (95%CI) 1, 3, and 6 years after TPVI were as follows: infective endocarditis, 0.5% (0.0%-1.0%), 0.9% (0.2%-1.6%), and 3.8% (0.0%-8.4%); pulmonary valve replacement, 0.4% (0.0%-0.8%), 1.3% (0.2%-2.4%), and 8.0% (1.2%-14.8%); and pulmonary valve thrombosis, 0.4% (0.0%-0.9%), 0.7% (0.0%-1.3%), and 0.7% (0.0%-1.3%), respectively.

CONCLUSIONS

Outcomes of SAPIEN 3 TPVI were favourable in patients with CHD, half of whom had native or patched RVOTs.

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.

[Modern possibilities for transcatheter pulmonary valve replacement]

The literature review is devoted to transcatheter pulmonary valve replacement. The authors summarize the indications, clinical data and current capabilities of transcatheter pulmonary valve replacement. The authors also overviewed modern valves for transcatheter pulmonary artery replacement. Effectiveness of transcatheter pulmonary valve implantation has been substantiated. Various studies comparing the outcomes of different valve systems for endovascular implantation were analyzed. The authors concluded the prospects for transcatheter pulmonary valve implantation.

A Modified Technique for Transcatheter Pulmonary Valve Implantation of SAPIEN 3 Valves in Large Right Ventricular Outflow Tract: A Matched Comparison Study

INTRODUCTION

Percutaneous pulmonary valve implantation (PPVI) with a SAPIEN 3 valve is effective for treating treat right ventricle outflow (RVOT) dysfunction. A modified technique was developed without prestenting using a protective valve delivery method. We aimed to compare the procedural results of the modified technique group (MTG) to those of patients in a conventional technique group (CTG).

METHODS

We designed a matched before-after study. All consecutive PPVI with SAPIEN 3 performed in the MTG over 9 months were matched, based on the RVOT type and size, to consecutive procedures performed previously with SAPIEN 3.

RESULTS

A total of 54 patients were included, equally distributed in the two groups. The sizes of the SAPIEN 3 valves were 23 mm (n = 9), 26 mm (n = 9), 29 mm (n = 36). The two groups were similar regarding demographic data, RVOT type, and pre-procedure hemodynamics. PPVI was performed in a single procedure in all patients of the MTG, whereas six (22.2%) patients of the CTG group underwent prestenting as a first step and valve implantation later (p = 0.02). The procedures were successful in all cases. Stent embolization was reported in two patients (7.4%) in the CTG, which were impacted in pulmonary arteries. In one case (3.7%), in the MTG, an unstable 29 mm SAPIEN 3 valve was stabilized with two stents and additional valve-in-valve implantation. The hemodynamics results were good in all cases, without significant differences between the two groups. The procedures' durations and fluoroscopy times were significantly reduced in the MTG (48.1 versus 82.6 min, p < 0.0001; 15.2 versus 29.8 min, p = 0.0002). During follow-up, neither stent fracture nor valve dysfunction was noticed in either group.

CONCLUSION

PPVI without prestenting and with a protective delivery method of the SAPIEN 3 valve significantly reduces the procedure's complexity, the duration, and the irradiation while maintaining excellent hemodynamics results in selected cases.

Valved Conduits for Right Ventricular Outflow Tract Reconstruction: A Review of Current Technologies and Future Directions

The need for right ventricular outflow tract reconstruction is common and growing in congenital heart surgery given expanding indications for the repair of congenital as well as acquired heart disease. Various valved conduit options currently exist including homografts, xenograft pulmonary valved conduits (Contegra™), and porcine valved conduits. The major limitation for all conduits is implant durability, which requires reoperation. Currently, cryopreserved homografts are often used given their superiority shown in long-term data. Significant limitations remain in the cost and availability of the graft, particularly for smaller sizes. Contegra conduits are available in a variety of sizes. Nonetheless, the data regarding long-term durability are less robust and studies comparing durability with homografts have been conflicting. Additionally, there is concern for increased rates of late endocarditis in this conduit. Porcine valved conduits offer a reliable option but are limited by structural valve degeneration associated with all types of bioprosthetic heart valve replacements. New developments in the field of tissue engineering have produced promising bio-restorative valved conduits that may overcome many of the limitations of previous conduit technologies. These remain in the early stages of clinical testing. This review summarizes the clinical data surrounding the conduits used most commonly in clinical practice today and explores emerging technologies that may bring us closer to developing the ideal conduit.

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.

Over-expansion of right ventricle to pulmonary artery conduits during transcatheter pulmonary valve placement

OBJECTIVES

To determine the safety and feasibility of over-expansion of right ventricle to pulmonary artery conduits during transcatheter pulmonary valve placement.

BACKGROUND

Transcatheter pulmonary valve placement is an alternative to surgical pulmonary valve replacement. Traditionally, it was thought to be unsafe to expand a conduit to >110% of its original size.

METHODS

This retrospective cohort study from two centers includes patients with right ventricle to pulmonary artery conduits with attempted transcatheter pulmonary valve placement from 2010 to 2017. Demographic, procedural, echocardiographic and follow-up data, and complications were evaluated in control and overdilation (to >110% original conduit size) groups.

RESULTS

One hundred and seventy-two patients (51 overdilation and 121 control) had attempted transcatheter pulmonary valve placement (98% successful). The overdilation group was younger (11.2 versus 16.7 years, p < 0.001) with smaller conduits (15 versus 22 mm, p < 0.001); however, the final valve size was not significantly different (19.7 versus 20.2 mm, p = 0.2). Baseline peak echocardiographic gradient was no different (51.8 versus 55.6 mmHg, p = 0.3). Procedural complications were more frequent in overdilation (18%) than control (7%) groups (most successfully addressed during the procedure). One patient from each group required urgent surgical intervention, with no procedural mortality. Follow-up echocardiographic peak gradients were similar (24.1 versus 26 mmHg, p = 0.5).

CONCLUSIONS

Over-expansion of right ventricle to pulmonary artery conduits during transcatheter pulmonary valve placement can be performed successfully. Procedural complications are more frequent with conduit overdilation, but there was no difference in the rate of life-threatening complications. There was no difference in valve function at most recent follow-up, and no difference in rate of reintervention. The long-term outcomes of transcatheter pulmonary valve placement with conduit over-expansion requires further study.

Simultaneous Stenting With Edwards SAPIEN Transcatheter Pulmonary Valve Replacement

Background

Prestenting of the landing zone for transcatheter pulmonary valve replacement (TPVR) with a balloon-expandable valve can dilate a stenotic right ventricular outflow tract (RVOT), prevent paravalvar leak (PVL), and protect against conduit tear. Simultaneous stenting (SS) with the Melody valve has been described, but to our knowledge, SS with a SAPIEN valve has not been reported. We report our experience with this novel technique.

Methods

A retrospective chart review of patients who underwent TPVR at Rady Children's hospital and UCSD Medical Center was performed. Patients were included if they had underwent SAPIEN TPVR with SS. Rationale for stent choice was a bare metal stent to relieve long-segment stenosis and covered stents to prevent PVL or to protect against conduit tear.

Results

A total of 17 cases were identified. The majority of RVOTs were transannular patches (n = 9, 56%), with a minimum diameter of 19.6 ± 5.2 mm, and the most common valve placed was an Edwards SAPIEN 26.0 mm (n = 10, 59%). All SAPIEN valves placed were of the S3 generation. The procedure was successful in all patients, with no conduit tears. Minor complications occurred in 3 patients (17.6%).

Conclusions

Simultaneous stent deployment with a SAPIEN TPVR is an alternative 1-step technique for patients who require prestenting. SS simplifies the procedure, has low complication rates, and offers the benefits of a longer landing zone and decreased PVL.

Piggyback mounting for stent and valve deployment during percutaneous pulmonary valve implantation

OBJECTIVES

We report our experience in simultaneously implanting multiple stents and valves mounted on a single balloon before and during transcatheter pulmonary valve placement.

BACKGROUND

Heterogeneity and complexity of the right ventricular outflow tract (RVOT) may complicate stent deployment when preparing a landing zone for transcatheter pulmonary valve implantation.

METHODS

Retrospective analysis of patients from Children's Hospital of Colorado, USA; and Oslo University Hospital, Norway, undergoing transcatheter pulmonary valve replacement that had at least two stents mounted on a single balloon, deployed in the RVOT.

RESULTS

Over a 42-month period, a total of 50 subjects from the two centers met inclusion criteria for the study. Subjects were predominantly male (58%), and the median age was 17 years (4-78 years). In six subjects (12%), there was need for prestenting with use of the double or triple stent piggyback technique. Forty subjects (80%) had a Melody ™ TPV implanted. In 45 cases (90%), one or more stents were mounted over the pulmonary valve using its delivery system, either the Ensemble for the Melody™ TPV or the Edwards Commander for the SAPIEN 3 THV. Thirty-seven subjects (74%) had one stent mounted and eight subjects (16%) had two stents mounted over the pulmonary valve for simultaneous deployment. No complications related to this technique were reported.

CONCLUSIONS

The piggyback technique aims to simplify and facilitate adequate conduit preparation and valve insertion by minimizing manipulation across the outflow tract and decreasing the risk of stent distortion, misalignment, and embolization.

Pre- and Postprocedure Imaging of Transcatheter Pulmonary Valve Implantation

Transcatheter pulmonary valve replacement (TPVR) is a minimally invasive procedure for treatment of right ventricular outflow tract (RVOT) dysfunction in surgically repaired congenital heart diseases. TPVR is performed in these patients to avoid the high risk and complexity of repeat surgeries. Several TPVR devices are now available to be placed in the right ventricle (RV) to pulmonary artery (PA) conduit, native RVOT, or surgical bioprosthetic valves. Imaging is used before TPVR to determine patient eligibility and optimal timing, which is critical to avoid irreversible RV dilatation and failure. Imaging is also required for evaluation of contraindications, particularly proximity of the RVOT to the left main coronary artery and its branches. Cross-sectional imaging provides details of the complex anatomy in which the TPVR device will be positioned and measurements of the RVOT, RV-PA conduit, or PA. Echocardiography is the first-line imaging modality for evaluation of the RVOT or conduit to determine the need for intervention, although its utility is limited by the complex RVOT morphology and altered anatomy after surgery. CT and MRI provide complementary information for TPVR, including patient eligibility, assessment of contraindications, and key measurements of the RVOT and PA, which are necessary for procedure planning. TPVR, performed using a cardiac catheterization procedure, includes a sizing step in which a balloon is expanded in the RVOT, which also allows assessment of the risk for extrinsic coronary artery compression. Follow-up imaging with CT and MRI is used for evaluation of postprocedure remodeling and valve function and to monitor complications. ^©RSNA, 2022 Online supplemental material is available for this article.

Reintervention and Survival After Transcatheter Pulmonary Valve Replacement

BACKGROUND

Transcatheter pulmonary valve (TPV) replacement (TPVR) has become the standard therapy for postoperative pulmonary outflow tract dysfunction in patients with a prosthetic conduit/valve, but there is limited information about risk factors for death or reintervention after this procedure.

OBJECTIVES

This study sought to evaluate mid- and long-term outcomes after TPVR in a large multicenter cohort.

METHODS

International registry focused on time-related outcomes after TPVR.

RESULTS

Investigators submitted data for 2,476 patients who underwent TPVR and were followed up for 8,475 patient-years. A total of 95 patients died after TPVR, most commonly from heart failure (n = 24). The cumulative incidence of death was 8.9% (95% CI: 6.9%-11.5%) 8 years after TPVR. On multivariable analysis, age at TPVR (HR: 1.04 per year; 95% CI: 1.03-1.06 per year; P < 0.001), a prosthetic valve in other positions (HR: 2.1; 95% CI: 1.2-3.7; P = 0.014), and an existing transvenous pacemaker/implantable cardioverter-defibrillator (HR: 2.1; 95% CI: 1.3-3.4; P = 0.004) were associated with death. A total of 258 patients underwent TPV reintervention. At 8 years, the cumulative incidence of any TPV reintervention was 25.1% (95% CI: 21.8%-28.5%) and of surgical TPV reintervention was 14.4% (95% CI: 11.9%-17.2%). Risk factors for surgical reintervention included age (0.95 per year [95% CI: 0.93-0.97 per year]; P < 0.001), prior endocarditis (2.5 [95% CI: 1.4-4.3]; P = 0.001), TPVR into a stented bioprosthetic valve (1.7 [95% CI: 1.2-2.5]; P = 0.007), and postimplant gradient (1.4 per 10 mm Hg [95% CI: 1.2-1.7 per 10 mm Hg]: P < 0.001).

CONCLUSIONS

These findings support the conclusion that survival and freedom from reintervention or surgery after TPVR are generally comparable to outcomes of surgical conduit/valve replacement across a wide age range.

Covered Stents in the Management of Aortic Coarctation and Right Ventricular Outflow Tract Obstruction

PURPOSE OF REVIEW

To review the use of covered stents in the treatment of coarctation of the aorta (CoA) and right ventricle to pulmonary artery (RV-PA) conduit obstruction.

RECENT FINDINGS

The only commercially available covered stent approved for treatment of CoA and dysfunctional RV-PA conduits is the covered Cheatham-Platinum stent (CCPS). Early outcomes have demonstrated its safety and have suggested its efficacy in treating or preventing aortic wall injury (AWI) or conduit disruption. A recent study of CCPS use for CoA reported a progressive risk of stent fracture over time and a risk of AWI despite the purported protection that the CCPS provides. The use of other covered stents has been reported, but large, systematic studies are lacking. CCPS use may reduce but does not eliminate the risk of conduit disruption or AWI. Structural limitations of the CCPS may predispose it to stent fracture. Access to a broad range of covered stents continues to be an unmet need in the field of congenital interventional cardiology.

Coronary Artery Anomalies and Their Impact on the Feasibility of Percutaneous Pulmonary Valve Implantation

One of the major obstacles preventing successful percutaneous pulmonary valve implantation (PPVI) is related to the close proximity of coronary artery branches to the expected landing zone. The aim of this study was to assess the frequency of coronary artery anomalies (CAAs) especially those associated with major coronary branches crossing the right ventricular outflow tract (RVOT) and to describe their relevance for the feasibility of percutaneous pulmonary valve implantation (PPVI). In our retrospective single-center study 90 patients were evaluated who underwent invasive testing for PPVI in our institution from 1/2010 to 1/2020. CAAs were identified in seven patients (8%) associated with major branches crossing the RVOT due to origin of the left anterior descending (LAD) or a single coronary artery from the right aortic sinus. In 5/7 patients with CAAs balloon testing of the RVOT and selective coronary angiographies revealed a sufficiently large landing zone distal to the coronary artery branch. While unfavorable RVOT dimensions prevented PPVI in one, PPVI was performed successfully in the remaining four patients. The relatively short landing zone required application of the "folded" melody technique in two patients. All patients are doing well (mean follow-up 3 years). CAAs associated with major coronary branches crossing the RVOT can be expected in about 8% of patients who are potential candidates for PPVI. Since the LAD crossed the RVOT below the plane of the pulmonary valve successful distal implantation of the valve was possible in 4/7 patients. Therefore these coronary anomalies should not be considered as primary contraindications for PPVI.

Choosing an appropriate size valve for transcatheter pulmonary valve implantation in a native right ventricle outflow tract

Introduction:

Transcatheter pulmonary valve implantation has been an effective treatment for dysfuntional right ventricular tract outflow tract (RVOT). Defining a landing zone before the intervention is crucial in patients with native RVOT. Improper sizing and undefined landing zone will lead to embolization.

Methods:

It is a retrospective observational study from August 2020 to December 2020 in native RVOT. Three patients who had significant Right ventricle dilatation were analyzed. The multi-slice computed tomography (MSCT) with magnetic resonance imaging and angiography data of all patients before the procedure were analyzed. All patients underwent an angiogram in the same sitting, before the procedure to assess the landing zone, valve diameter as well as the risk for coronary compression. We chose a valve based on valve area 23%–25% more than the area at the waist during balloon sizing.

Results:

All three patients underwent successful valve implantation. Valve sizes used were 27.5 mm in one and 32 mm in the other two. The mean RVOT gradient postprocedure was 11.5 mm Hg and pre procedure was 43 mmHg. There were no complications during the procedure or at a mean follow-up of 3.6 months.

Conclusion:

The balloon sizing gives the true narrowest diameter in comparison with MSCT, and increasing this area by 23%–25% will give the appropriate valve size for successful implantation.

Long-Term Outcomes After Melody Transcatheter Pulmonary Valve Replacement in the US Investigational Device Exemption Trial

Supplemental Digital Content is available in the text.

Background:

The Melody valve was developed to extend the useful life of previously implanted right ventricular outflow tract (RVOT) conduits or bioprosthetic pulmonary valves, while preserving RV function and reducing the lifetime burden of surgery for patients with complex congenital heart disease.

Methods:

Enrollment for the US Investigational Device Exemption study of the Melody valve began in 2007. Extended follow-up was completed in 2020. The primary outcome was freedom from transcatheter pulmonary valve (TPV) dysfunction (freedom from reoperation, reintervention, moderate or severe pulmonary regurgitation, and/or mean RVOT gradient >40 mm Hg). Secondary end points included stent fracture, catheter reintervention, surgical conduit replacement, and death.

Results:

One hundred seventy-one subjects with RVOT conduit or bioprosthetic pulmonary valve dysfunction were enrolled. One hundred fifty underwent Melody TPV replacement. Median age was 19 years (Q1–Q3: 15–26). Median discharge mean RVOT Doppler gradient was 17 mm Hg (Q1–Q3: 12–22). The 149 patients implanted >24 hours were followed for a median of 8.4 years (Q1–Q3: 5.4–10.1). At 10 years, estimated freedom from mortality was 90%, from reoperation 79%, and from any reintervention 60%. Ten-year freedom from TPV dysfunction was 53% and was significantly shorter in children than in adults. Estimated freedom from TPV-related endocarditis was 81% at 10 years (95% CI, 69%–89%), with an annualized rate of 2.0% per patient-year.

Conclusions:

Ten-year outcomes from the Melody Investigational Device Exemption trial affirm the benefits of Melody TPV replacement in the lifetime management of patients with RVOT conduits and bioprosthetic pulmonary valves by providing sustained symptomatic and hemodynamic improvement in the majority of patients.

Registration:

URL: https://www.clinicaltrials.gov; Unique identifier: NCT00740870.

Case report: successful emergent transcatheter pulmonary valve replacement within failing pulmonary artery conduit in the setting of cardiogenic shock with extracorporeal membrane oxygenation support

Background

To the best of our knowledge, this is the first reported case of transcatheter pulmonary valve replacement (TPVR) with extracorporeal membrane oxygenation (ECMO) support with successful decannulation as a bridge to recovery in a young adult with complex congenital heart disease.

Case summary

We describe a 24-year-old male patient with a history of D-transposition of the great arteries with ventricular septal defect status post-Rastelli repair at age three lost to follow-up and presenting with severe biventricular failure, left ventricular thrombus, and critical pulmonary conduit stenosis, deemed non-surgical and non-transplant candidate, who underwent conduit stenting and TPVR in the setting of cardiogenic shock. Upon intubation for general anaesthesia, the patient suffered from ventricular tachycardia arrest requiring cardiopulmonary resuscitation and veno-arterial ECMO. Once stabilized, conduit stenting and TPVR was performed with significant haemodynamic improvement and immediate ECMO decannulation with subsequent biventricular function improvement.

Discussion

In critically ill patients with complex congenital heart disease that are neither surgical nor transplant candidates, ECMO support can be used as a means of support during a transcatheter intervention to improve haemodynamics and a bridge to recovery, allowing time for future potential candidacy for surgery or transplantation as indicated. Patients with congenital heart disease need regular follow-up in specialty clinics to prevent the development of such critical illness.

Aspirin Use and Transcatheter Pulmonary Valve Replacement, the Need for Consistency

Transcatheter pulmonary valve replacement (TPVR) is a staple in the pediatric cardiac catheterization lab. Despite the ubiquitous use of this procedure, guidelines for antithrombosis post pulmonary valve replacement are non-existent. A survey was sent out via email to the members of the Congenital Cardiovascular Interventional Study Consortium (CCISC) and the Pediatric and Adult Interventional Cardiac Symposium (PICS-AICS). Responses were received from 109 cardiologists who perform this procedure. Following TPVR 76.5% of respondents use only Aspirin, while the remainder prescribe a second antithrombotic agent at discharge. The majority (78%) of respondents do not educate patients about avoiding enteric formulations of aspirin, and another 86% do not educate patients about the need to avoid proton pump inhibitors (PPI). In addition, 67% do not advise against concomitant use of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs). Lastly, the survey showed a wide discrepancy in prescribed dose with 56% choosing to always prescribe 70-100 mg regardless of weight, 28% choosing to do weight-based dosing, and 7.5% choosing 325 mg regardless of weight. In a survey sent out to pediatric cardiac interventionalists worldwide, a significant discrepancy was noted in antithrombotic regimens used following TPVR. We hypothesize that these discrepancies may contribute to early valve failure and suggest the need for further study and the development of unified antithrombosis guidelines following TPVR.

A New Solution for Stenting Large Right Ventricular Outflow Tracts Before Transcatheter Pulmonary Valve Replacement

BACKGROUND

Prestenting right ventricular outflow tracts (RVOTs) before transcatheter pulmonary valve replacement (TPVR) is essential. Optimus-XXL (AndraTec GmbH, Koblenz, Germany) is a new extra-large, balloon-expandable cobalt-chrome stent with promising technologies.

METHODS

From June 2020 to November 2020, 15 patients with congenital heart disease, dysfunctional RVOTs and target TPVR diameter ≥ 23 mm received Optimus-XXL stents before proceeding to TPVR using the SAPIEN valve (Edwards Lifesciences, Irvine, CA). Standard safety and outcomes were prospectively assessed.

RESULTS

Patients' median age and weight were 25.8 years (range: 10.5-63.1 years) and 58 kg (range: 43.8-101 kg), respectively. Underlying diagnosis was tetralogy of Fallot (66.7%), and RVOTs were patched (80%). Fifteen bare-metal stents were implanted using femoral (n = 14) and jugular approaches (n = 1). One conduit rupture was immediately controlled with a covered Optimus-XXL. Median stent length was 43 mm (range: 33-57 mm), and median target expansion diameter was 28 mm (range: 23-30 mm). Two procedural incidents occurred during stent delivery and were percutaneously treated. Stent stability was documented during TPVRs immediately performed in 14 patients. Median stent shortening was 13.7%, and median percentage of intended stent expansion was 95.9%. There was no stent fracture on the short-term follow-up (median: 4.5 months).

CONCLUSIONS

We report the first implantations of Optimus-XXL stents in dysfunctional RVOTs with excellent preliminary results. Optimus-XXL should be considered as a valuable adjunct in the armamentarium for routine and complex TPVR procedures.

Contrast-free percutaneous pulmonary valve replacement: a safe approach for valve-in-valve procedures

Introduction

Percutaneous pulmonary valve replacement (PPVI) continues to gather pace in pediatric and adult congenital practice. This is fueled by an expanding repertoire of devices, techniques and equipment to suit the heterogenous anatomical landscape of patients with lesions of the right ventricular outflow tract (RVOT). Contrast-induced nephropathy is a real risk for teenagers and adults with congenital heart disease (CHD).

Aim

To present a series of patients who underwent PPVI without formal RVOT angiography and propose case selection criteria for patients who may safely benefit from this approach.

Material and methods

We retrospectively collected PPVI data from the preceding 2 years at our institution identifying patients who had been listed as suitable for consideration for contrast-free PPVI from our multidisciplinary team (MDT) meeting based on predefined criteria. Demographic, clinical, imaging and hemodynamic data were collected. Data were analyzed using SPSS.

Results

Twenty-one patients were identified. All patients had a technically successful implantation with improvements seen in invasive and echocardiographic hemodynamic measurements. 90% of patients had a bio-prosthetic valve (BPV) in situ prior to PPVI. One patient had a complication which may have been recognized earlier with post-intervention RVOT contrast injection.

Conclusions

Zero-contrast PPVI is technically feasible and the suitability criteria for those who might benefit are potentially straightforward. The advent of fusion and 3D imaging in cardiac catheterization laboratories is likely to expand our capacity to perform more procedures with less contrast. Patients with bio-prosthetic valves in the pulmonary position may benefit from contrast-free percutaneous pulmonary valve implantation.

Edwards SAPIEN XT transcatheter pulmonary valve implantation: 5-year follow-up in a French Registry

OBJECTIVES

This study sought to investigate patient intermediate-term outcomes after transcatheter pulmonary valve replacement (TPVR) with Edwards SAPIEN valve.

BACKGROUND

The Edwards SAPIEN valve, initially designed for percutaneous aortic valve replacement, has been approved for TPVR in patients with dysfunctional right ventricular outflow tracts (RVOT), but only short-term follow-up has been reported.

METHODS

From 2011 to 2016, 62 patients undergoing successful TPVR using the SAPIEN XT valve were consecutively included into the study. Primary efficacy and safety endpoints were defined as freedom from valve-reintervention and freedom from infective endocarditis at last follow-up, respectively.

RESULTS

The primary efficacy outcome was met for 87.1% patients after a mean follow-up of 4.6 ± 1.8 years, corresponding to a freedom of reintervention at 5 years of 89% (95% CI 74.8-95.6%). Reinterventions were exclusively due to recurrent obstruction, no significant valvular regurgitation was observed. One case of infective endocarditis was reported, corresponding to a rate of 0.35% per patient-year (95% CI 0.01-2.00%). At 5 years, freedom from infective endocarditis was 98.4% (95% CI 89.1-99.8%). Six patients died or were transplanted due to advanced cardiac failure, without relationship with TPVR. In univariate analysis, reintervention was associated with young age, a smaller tube-graft, a higher pulmonary valve gradient after the procedure and a ratio of largest implanted stent diameter to invasive balloon conduit diameter over 1.35.

CONCLUSIONS

This study documents the mid-term safety and efficacy of the Edwards SAPIEN XT valve in patients with dysfunctional RVOT, and identifies a patient profile associated with an uncertain benefit-risk balance.

Semilunar Valve Interventions for Congenital Heart Disease: JACC State-of-the-Art Review

Transcatheter balloon valvuloplasty for the treatment of aortic and pulmonary valve stenosis was first described nearly 40 years ago. Since that time, the technique has been refined in an effort to optimize acute outcomes while reducing the long-term need for reintervention and valve replacement. Balloon pulmonary valvuloplasty is considered first-line therapy for pulmonary valve stenosis and generally results in successful relief of valvar obstruction. Larger balloon to annulus (BAR) diameter ratios can increase the risk for significant valvar regurgitation. However, the development of regurgitation resulting in right ventricular dilation and dysfunction necessitating pulmonary valve replacement is uncommon in long-term follow-up. Balloon aortic valvuloplasty has generally been the first-line therapy for aortic valve stenosis, although some contemporary studies have documented improved outcomes following surgical valvuloplasty in a subset of patients who achieve tri-leaflet valve morphology following surgical repair. Over time, progressive aortic regurgitation is common and frequently results in the need for aortic valve replacement. Neonates with critical aortic valve stenosis remain a particularly high-risk group. More contemporary data suggest that acutely achieving an aortic valve gradient <35 mm Hg with mild aortic regurgitation may improve long-term valve performance and reduce the need for valve replacement. Continued study will help to further improve outcomes and reduce the need for future reinterventions.

Comparison of the investigational device exemption and post-approval trials of the Melody transcatheter pulmonary valve

OBJECTIVE

We compared 5-year outcomes of transcatheter pulmonary valve (TPV) replacement with the Melody TPV in the post-approval study (PAS) and the investigational device exemption (IDE) trial.

BACKGROUND

As a condition of approval of the Melody TPV after the IDE trial, the Food and Drug Administration required that a PAS be conducted to evaluate outcomes of TPV replacement in a "real-world" environment. The 5-year outcomes of the PAS have not been published, and the IDE and PAS trials have not been compared.

METHODS

The cohorts comprised all patients catheterized and implanted at 5 IDE sites and 10 PAS sites. Differences in trial protocols were detailed. Time-related outcomes and valve-related adverse events were compared between the two trials with Kaplan-Meier curves and log-rank testing.

RESULTS

167 patients (median age, 19 years) were catheterized and 150 underwent TPV replacement in the IDE trial; 121 were catheterized (median age, 17 years) and 100 implanted in the PAS. Freedom from hemodynamic dysfunction (p = .61) or any reintervention (p = .74) over time did not differ between trials. Freedom from stent fracture (p = .003) and transcatheter reintervention (p = .010) were longer in PAS, whereas freedom from explant (p = .020) and TPV endocarditis (p = .007) were shorter. Clinically important adverse events (AEs) were reported in 14% of PAS and 7.2% of IDE patients (p = .056); the incidence of any particular event was low in both.

CONCLUSIONS

Hemodynamic and time-related outcomes in the PAS and IDE trials were generally similar, confirming the effectiveness of the Melody TPV with real-world providers. There were few significant complications and limited power to identify important differences in AEs. The lack of major differences in outcomes between the two studies questions the usefulness of mandated costly post-approval studies as part of the regulatory process for Class III medical devices.

Mid-Term Outcomes Following Percutaneous Pulmonary Valve Implantation Using the "Folded Melody Valve" Technique

Background:

The folded valve is a manual shortening of the Melody device, which has been validated as a valuable therapeutic option for the management of dysfunctional right ventricular outflow tracts needing a short valved stent. In this article, we aimed to evaluate, in a multicenter cohort, the mid-term outcomes of patients in whom a percutaneous pulmonary valve implantation was performed using the folded valve technique.

Methods:

A 2012 to 2018 retrospective multicenter study was performed in 7 European institutions. All patients who benefit from percutaneous pulmonary valve implantation with a folded Melody valve were included.

Results:

A total of 49 patients (median age, 19 years [range 4–56], 63% male) were included. The primary percutaneous pulmonary valve implantation indication was right ventricular outflow tract stenosis (n=19; 39%), patched native right ventricular outflow tracts were the most common substrate (n=15; 31%). The folded technique was mostly used in short right ventricular outflow tracts (n=28; 57%). Procedural success was 100%. After a median follow-up of 28 months (range, 4–80), folded Melody valve function was comparable to the immediate postimplantation period (mean transvalvular peak velocity=2.6±0.6 versus 2.4±0.6 m/s, P>0.1; only 2 patients had mild pulmonary regurgitation). Incidence rate of valve-related reinterventions was 2.1% per person per year (95% CI, 0.1%–3.9%). The probability of survival without valve-related reinterventions at 36 months was 90% (95% CI, 76%–100%).

Conclusions:

The folded Melody valve is a safe technique with favorable mid-term outcomes up to 6.5 years after implantation, comparable with the usual Melody valve implantation procedure. Complications and reinterventions rates were low, making this technique relevant in selected patients.

Morphological changes and number of candidates for transcatheter pulmonary valve implantation in conduits involving heterograft and artificial material

Heterograft and artificial materials have been used for extracardiac conduit implantation to create right ventricular (RV) to pulmonary artery (PA) continuity for biventricular repair in Japan because of the limited availability of homograft valves. However, few studies have examined morphological changes and number of candidates for transcatheter pulmonary valve implantation (TPVI) in which the conduit includes more than one type of material. Overall, 88 patients who underwent biventricular repair with an external conduit were included in this evaluation. Based on catheterization data and surgical records, we estimated morphological change in the RV outflow tract for each material and the number of candidates for Melody valve implantation based on premarket approval application criteria established by the U.S. Food and Drug Administration. There were 63 candidates for TPVI (72%, 63/88). Median anteroposterior and lateral diameter of the RV outflow tract was 20.4 mm (range 9.0-41.5) and 17.8 mm (range 9.5-34.9), respectively. Bovine pericardium tended to dilate by 11.2%. Polytetrafluoroethylene (ePTFE), homograft, and Dacron polyethylene terephthalate (PET) tended to become stenotic by 11.1%, 28.0%, and 13.4%, respectively. While ePTFE (27/33, 82%) and Dacron PET (2/2, 100%) were highly suitable for TPVI, bovine pericardium (32/48, 67%) was less suitable. In Japan, many patients with hemodynamic indications for TPVI following extracardiac conduit implantation to create RV to PA continuity may also meet the morphological indications.

Bilateral Percutaneous Pulmonary Valves for Severe Pulmonary Regurgitation in a Patient with Prior Valvotomy

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Severe PR is a common long-term complication after valvotomy.

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There are no current endovascular valves for severe dilation of the main PA.

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Implantation of transcatheter valves in the main PA branches is an alternative.

Melody Valve Fracture Causing Mitral Stenosis: Novel Solution for Transapical Valve-in-Valve

The use of Melody valves in the mitral position has been introduced in clinical practice. Stent fracture is a recognized complication of Melody valve implantation in the pulmonary position; however, reports in the mitral position are rare. We present the case of an 8-year-old boy in whom complete fracture of the proximal stent struts occurred, causing acute severe mitral stenosis, and in whom urgent hybrid transapical Melody valve implantation in the fractured Melody valve was performed successfully using a novel modified technique. This modification simplified the implantation, led to reduced time of the procedure, and minimized hemodynamic instability.

Prevention and management of endocarditis after transcatheter pulmonary valve replacement: current status and future prospects

Introduction: Transcatheter pulmonary valve replacement (TPVR) has become an important tool in the management of congenital heart disease with abnormalities of the right ventricular outflow tract. Endocarditis is one of the most serious adverse long-term outcomes and among the leading causes of death in patients with congenital heart disease and after (TPVR).Areas covered: This review discusses the current state knowledge about the risk factors for and outcomes of endocarditis after transcatheter pulmonary valve replacement in patients with congenital and acquired heart disease. It also addresses practical measures for mitigating endocarditis risk, as well as diagnosing and managing endocarditis when it does occur.Expert opinion: With increasing understanding of the risk factors for and management and outcomes of endocarditis in patients who have undergone TPVR, we continue to learn how to utilize TPVR most effectively in this complex population of patients.

Pulmonary regurgitation after repaired tetralogy of Fallot: surgical versus percutaneous treatment

Pulmonary regurgitation is the most important sequellae after correction of Tetralogy of Fallot and has a considerable impact over the right ventricle. Surgery has demonstrated low early mortality after pulmonary valve replacement and good long-term outcomes, remaining nowadays the gold standard treatment of pulmonary regurgitation in rTOF patients. Nevertheless, transcatheter pulmonary valve implantation has emerged as a new, safe and efficient alternative to surgical valve replacement. In this review article, we try to evaluate and compare both techniques to find out which is the best therapeutic option in this patients.

Covered CP Stent for Treatment of Right Ventricular Conduit Injury During Melody Transcatheter Pulmonary Valve Replacement

BACKGROUND

High-pressure balloon and stent angioplasty are frequently necessary to prepare the dysfunctional right ventricular outflow tract conduit before transcatheter pulmonary valve replacement (TPVR). Conduit injury can result, which may be catastrophic to the patient or prevent successful TPVR.

METHODS AND RESULTS

The PARCS trial (Pulmonary Artery Repair With Covered Stent) was a pivotal, prospective multicenter trial to evaluate the safety and efficacy of the NuMED Covered CP Stent (CCPS) for treatment of conduit injury occurring during TPVR. The study also evaluated immediate and short-term TPVR function in patients receiving covered stents. A total of 616 patients were consented; 120 (19.5%) had a wall injury identified and were treated with CCPS. Severe conduit injuries were uncommon (5%), but predictors for severe injury were not identified. Stenotic homografts had the highest incidence of injury (29%), compared with other conduit substrates. Among patients receiving CCPS implant, 96% required no further therapy for conduit injury, and 94% underwent TPVR at that procedure. Only 2 patients (1.6%) required urgent surgery for conduit injury, despite CCPS implant. There were few CCPS-related complications. TPVR function was similar between CCPS and non-CCPS groups at follow-up.

CONCLUSIONS

Conduit injury during TPVR is common, although severe injury is rare. The CCPS was a safe and effective treatment for right ventricular outflow tract conduit injury during preparation for TPVR, allowing nearly all patients to complete the procedure without identifiable impact on valve performance.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01824160.

The Sapien valve provides enough grip to be implanted in pulmonary position without a pre-stent

Background

Pre-stenting is a widely used technique for transcatheter pulmonary valve implantation (TPVI). For the Melody valve a pre-stent creates a reliable and solid landing zone. In contrast to the Melody valve, the Edwards Sapien valve consists of a strong balloon expandable stent designed for implantation in the aortic position. The usage of a Sapien valve in pulmonary position might therefore obviate the need of a pre-stent.

Methods

This retrospective, single centre study reviewed the procedural outcomes of patients receiving the Sapien XT transcatheter valve in pulmonary position without prior implantation of a pre-stent. All consecutive patients with dysfunctional right ventricle to pulmonary artery (RV-PA) conduits or with dysfunctional pulmonary valve treated at the German Heart Centre in Munich were included in this study.

Results

We report on successful implantation of a Sapien XT/3 without usage of a pre-stent.

Conclusions

Abandonment of the pre-stent simplified the procedure and reduces the radiation burden for the patients.

Pulmonary Valve Replacement for Tetralogy of Fallot

Right ventricular outflow tract (RVOT) dysfunction is common following surgical repair of tetralogy of Fallot and other forms of complex congenital heart disease. This results in pulmonary stenosis or regurgitation and may ultimately lead to RV failure and dysrhythmias. Transcatheter valve technologies are now available to treat certain patients with RVOT dysfunction. Current devices include the Medtronic Melody valve and the Edwards Lifesciences SAPIEN XT. Although these valves are approved for use in dysfunctional circumferential RVOT conduits, they are increasingly being used off label for nonconduit outflow tracts. Procedural complications include but are not limited to conduit rupture and coronary compression. Longer-term complications include stent fracture and endocarditis. Outcomes with these valves have demonstrated durable relief of stenosis and regurgitation. The Medtronic Harmony valve and the Alterra Prestent from Edwards Lifesciences are investigational devices that are intended to treat the patulous RVOT that is too large to accommodate currently available valves. This review will focus on current indications to treat RVOT dysfunction, existing transcatheter valve technologies, and investigational devices undergoing clinical trials. Hopefully, within the not-too-distant future, transcatheter pulmonary valve implantation will be feasible in the vast majority of patients with RVOT dysfunction following surgical repair of congenital heart disease.

Intentional Fracture of Bioprosthetic Valve Frames in Patients Undergoing Valve-in-Valve Transcatheter Pulmonary Valve Replacement

BACKGROUND

Percutaneous transcatheter pulmonary valve replacement (TPVR) has good clinical and hemodynamic outcomes in treating dysfunctional bioprosthetic valves (BPV) in the pulmonary position. Valve-in-valve therapy can further decrease the inner diameter (ID), potentially resulting in patient-prosthesis mismatch in patients with smaller BPVs.

METHODS AND RESULTS

To evaluate feasibility and outcomes of intentional BPV fracture to enlarge the pulmonary valve orifice with TPVR, 37 patients from 13 centers who underwent TPVR with intended BPV fracture were evaluated. A control cohort (n=70) who underwent valve-in-valve TPVR without attempted fracture was evaluated. BPV was successfully fractured in 28 patients and stretched in 5 while fracture was unsuccessful in 4. A Melody valve was implanted in 25 patients with fractured/stretched frame and a Sapien (XT 3) valve in 8. Among patients whose BPV was fractured/stretched, the final ID was a median of 2 mm larger (0-6.5 mm) than the valve's true ID. The narrowest diameter after TPVR in controls was a median of 2 mm smaller ( P<0.001) than true ID. Right ventricular outflow tract gradient decreased from median 40 to 8 mm Hg in the fracture group. Cases with fracture/stretching were matched 1:1 (weight, true ID) to controls. Post-TPVR peak gradient was lower but not significant (8.3±5.2 versus 11.8±9.2 mm Hg; P=0.070). There were no fracture-related adverse events.

CONCLUSIONS

Preliminary experience shows intentional fracture of BPV frame can be useful for achieving larger ID and better hemodynamics after valve-in-valve TPVR.

Branch Pulmonary Artery Valve Implantation Reduces Pulmonary Regurgitation and Improves Right Ventricular Size/Function in Patients With Large Right Ventricular Outflow Tracts

OBJECTIVES

The authors sought to assess the intermediate-term effects of percutaneous placed valves in the branch pulmonary artery (PA) position.

BACKGROUND

Most patients with large right ventricular outflow tracts (RVOTs) are excluded from available percutaneous pulmonary valve options. In some of these patients, percutaneous branch PA valve implantation may be feasible. The longer-term effects of valves in the branch PA position is unknown.

METHODS

Retrospective data were collected on patients with significant pulmonary regurgitation who had a percutaneous branch PA valve attempted.

RESULTS

Percutaneous branch PA valve implantation was attempted in 34 patients (18 bilateral and 16 unilateral). One-half of the patients were in New York Heart Association (NHYA) functional class III or IV pre-implantation. There were 2 failed attempts and 6 procedural complications. At follow-up, only 1 patient had more than mild valvar regurgitation. The right ventricular end-diastolic volume index decreased from 147 (range: 103 to 478) ml/m² to 101 (range: 76 to 429) ml/m², p < 0.01 (n = 16), and the right ventricular end-systolic volume index decreased from 88.5 (range: 41 to 387) ml/m² to 55.5 (range: 40.2 to 347) ml/m², p < 0.01 (n = 13). There were 5 late deaths. At a median follow-up of 2 years, all other patients were in NYHA functional class I or II.

CONCLUSIONS

Percutaneous branch PA valve implantation results in a reduction in right ventricular volume with clinical benefit in the intermediate term. Until percutaneous valve technology for large RVOTs is refined and more widely available, branch PA valve implantation remains an option for select patients.

Transcatheter Pulmonary Valve Replacement With the Melody Valve in Small Diameter Expandable Right Ventricular Outflow Tract Conduits

OBJECTIVES

This study sought to evaluate the safety, feasibility, and outcomes of transcatheter pulmonary valve replacement (TPVR) in conduits ≤16 mm in diameter.

BACKGROUND

The Melody valve (Medtronic, Minneapolis, Minnesota) is approved for the treatment of dysfunctional right ventricular outflow tract (RVOT) conduits ≥16 mm in diameter at the time of implant. Limited data are available regarding the use of this device in smaller conduits.

METHODS

The study retrospectively evaluated patients from 9 centers who underwent percutaneous TPVR into a conduit that was ≤16 mm in diameter at the time of implant, and reported procedural characteristics and outcomes.

RESULTS

A total of 140 patients were included and 117 patients (78%; median age and weight 11 years of age and 35 kg, respectively) underwent successful TPVR. The median original conduit diameter was 15 (range: 9 to 16) mm, and the median narrowest conduit diameter was 11 (range: 4 to 23) mm. Conduits were enlarged to a median diameter of 19 mm (29% larger than the implanted diameter), with no difference between conduits. There was significant hemodynamic improvement post-implant, with a residual peak RVOT pressure gradient of 7 mm Hg (p < 0.001) and no significant pulmonary regurgitation. During a median follow-up of 2.0 years, freedom from RVOT reintervention was 97% and 89% at 2 and 4 years, respectively, and there were no deaths and 5 cases of endocarditis (incidence rate 2.0% per patient-year).

CONCLUSIONS

In this preliminary experience, TPVR with the Melody valve into expandable small diameter conduits was feasible and safe, with favorable early and long-term procedural and hemodynamic outcomes.

Percutaneous pulmonary valve implantation (PPVI) in non-obstructive right ventricular outflow tract: limitations and mid-term outcomes

BACKGROUND

Percutaneous pulmonary valve implantation (PPVI) has been established as a safe and effective alternative to surgery treating patients with a failing pulmonary valve conduit. Nevertheless, the majority of patients in need of a valve have a native, non-obstructive right ventricular outflow tract (RVOT). The current approved stent-valves have a balloon-expandable design. Pre-stenting of the RVOT to create a landing zone and also protect the valve stability is usually mandatory; large, non-obstructive RVOTs need pre-stenting to reduce the RVOT-diameter for a balloon-expandable valve implantation.

METHODS

A retrospective study design was used to analyze the medium-term outcome after PPVI in a series of 26 patients with native or reconstructed RVOT.

RESULTS

PPVI was successfully performed in all, but 1 (96%). Within the follow-up of a minimum of 2 years, the percutaneous implanted valves remained competent; a significant pressure gradient was not detected. Furthermore, no PPVI-related complications such as endocarditis, migration or stent fractures were observed. The electrocardiogram at rest, in particular the QRS duration remained unchanged immediate post-PPVI as well as at medium-term follow-up of 24 months. However, ventricular arrhythmias were documented in 3 patients (11.5%); all patients were successfully treated with antiarrhythmic drugs, utilizing metoprolol. A trial of an invasive catheter based RVOT-ablation in one remained unsuccessful; pre-stented RVOT did not allow a successful intervention.

CONCLUSIONS

Medium-term follow-up showed excellent results of the mechanical valve function. PPVI utilizing balloon-expandable stent-valves in a native RVOT remains an off-label use. Despite our encouraging results, advanced manipulations of the patched or native RVOT might be associated with significant ventricular arrhythmias. There is a need for less invasive RVOT reduction devices.

Implantation of the Melody transcatheter pulmonary valve PB1016 in patients with dysfunctional right ventricular outflow tract conduits

OBJECTIVES

This study describes procedural and 1-year outcomes of the 16 mm Melody PB1016 valve in patients with dysfunctional RVOT conduits.

BACKGROUND

The Melody PB1016 is a standard Melody valve produced from a 16 mm bovine jugular vein and is intended for deployment up to 20 mm.

METHODS

This is a prospective, non-randomized, multicenter study of the procedural and short-term outcomes of Melody PB1016 TPV replacement within dysfunctional RVOT conduits. Data from eight centers were included in the analysis.

RESULTS

During the study period, 39 patients underwent attempted Melody TPVR. Of the 39 patients, 30 underwent successful Melody TPVR. The majority of patients underwent placement of one or more stents prior to TPVR. There was a significant reduction in peak conduit pressure gradient following TPVR (38 mmHg vs. 11 mmHg, P < 0.001). There were three cases of confined conduit tears successfully treated with covered stents or the valve itself. Repeat catheterization was performed in one patient for early re-obstruction that was successfully treated with balloon valvuloplasty. At recent follow-up, there were no cases of more than mild valve regurgitation and the mean pulmonary valve gradient by echocardiogram remained reduced relative to pre-TPVR implant measurements (33.5 mmHg vs. 15.2 mmHg). There were no cases of valve stent fracture or endocarditis reported at the 1-year follow-up.

CONCLUSIONS

Our analysis of TPVR with the PB1016 valve in RVOT conduits showed it to be safe and effective and can be performed in a wide range of conduit sizes with preserved valve function. ClinicalTrials.gov Identifier: NCT02347189.

Repeat Pulmonary Valve Replacement: Similar Intermediate-Term Outcomes With Surgical and Transcatheter Procedures

OBJECTIVES

This study compares 30-day, 1-year, and 3-year echocardiographic findings and clinical outcomes of transcatheter pulmonary valve-in-valve replacement (TPVR) and repeat surgical pulmonary valve replacement (SPVR).

BACKGROUND

In patients with adult congenital heart disease and previous pulmonary valve replacement (PVR) who require redo PVR, it is unclear whether TPVR or repeat SPVR is the preferred strategy.

METHODS

We retrospectively identified 66 patients (TPVR, n = 36; SPVR, n = 30) with bioprosthetic pulmonary valves (PVs) who underwent either TPVR or repeat SPVR at Emory Healthcare from January 2007 to August 2017.

RESULTS

The TPVR cohort had fewer men and more patients with baseline New York Heart Association (NYHA) functional class III or IV. There was no difference in mortality, cardiovascular readmission, or post-procedural PV reintervention at 30 days, 1 year, or 3 years. Post-procedural echocardiographic findings showed no difference in mean PV gradients between the TPVR and SPVR groups at 30 days, 1 year, or 3 years. In the TPVR cohort, there was less right ventricular dysfunction at 30 days (2.9% vs. 46.7%; p < 0.01), despite higher baseline NYHA functional class in the SPVR cohort.

CONCLUSIONS

In patients with bioprosthetic PV dysfunction who underwent either TPVR or SPVR, there was no difference in mortality, cardiovascular readmission, or repeat PV intervention at 30 days, 1 year, or 3 years. Additionally, TPVR and SPVR had similar intermediate-term PV longevity, with no difference in PV gradients or PVR. The TPVR cohort also had less right ventricular dysfunction at 30 days despite a higher baseline NYHA functional classification. These intermediate-term results suggest that TPVR may be an attractive alternative to SPVR in patients with previous bioprosthetic surgical PVs.