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

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.

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.

Non-Elective Pediatric Cardiac Catheterization During COVID-19 Pandemic: A New York Center Experience.

BACKGROUND: COVID-19 has led to major changes in hospital systems across the world. In an effort to reduce viral transmission, conserve resources, and in accordance with institutional and state mandates, all elective procedures and surgeries were postponed during the initial outbreak. Guidelines for case selection are limited and management for pediatric catheterization laboratories during this crisis is unprecedented. OBJECTIVES: To report the protocols and case selection of a high-volume pediatric cardiac catheterization laboratory in the epicenter of the novel coronavirus (COVID-19) pandemic. METHODS: All pediatric cardiac catheterization procedures from March 16, 2020 through May 10, 2020 were reviewed. Changes to case selection and periprocedural workflow are described. Data were collected on COVID-19 testing status and primary procedure type, and all procedures were classified by urgency. RESULTS: There were 52 catheterizations performed on 50 patients. Endomyocardial biopsies were the most common procedure (n = 27; 52%). Interventional and diagnostic procedures represented 27% (n = 14) and 21% (n = 11) of cases, respectively. Two emergent procedures (3.8%) were performed on patients with positive COVID-19 testing. Most cases were performed on patients with negative COVID-19 testing (n = 33; 94%). CONCLUSIONS: Adjusting to the COVID-19 pandemic in a high-volume pediatric cardiac catheterization laboratory can be safely and effectively managed by prioritizing emergent and urgent cases and modifying workflow operations. The experience of this center may assist other pediatric cardiac catheterization laboratories in adapting to similar practice changes as the pandemic continues to evolve.

Outcomes After Transcatheter Reintervention for Dysfunction of a Previously Implanted Transcatheter Pulmonary Valve.

OBJECTIVES: The aim of this analysis was to evaluate outcomes following transcatheter reintervention for degenerated transcatheter pulmonary valves (TPVs). BACKGROUND: TPV replacement (TPVR) with the Melody valve demonstrated sustained relief of right ventricular outflow tract (RVOT) obstruction and pulmonary regurgitation. METHODS: All patients who underwent TPVR with a Melody valve as part of 3 Medtronic-sponsored prospective multicenter studies were included. Transcatheter reinterventions included balloon dilation of the previously implanted Melody valve, placement of a bare-metal stent within the implanted TPV, or placement of a new TPV in the RVOT (TPV-in-TPV). Indications for reintervention, decisions to reintervene, and the method of reintervention were at physician discretion. All patients provided written informed consent to participate in the trials, and each trial was approved by local or central Institutional Review Boards or ethics committees at participating sites. RESULTS: A total of 309 patients who underwent TPVR were discharged from the implantation hospitalization with Melody valves in place. Transcatheter reintervention on the TPV was performed in 46 patients. The first transcatheter reintervention consisted of TPV-in-TPV in 28 patients (median 6.9 years [quartile 1 to quartile 3: 5.2 to 7.8 years] after TPVR), simple balloon dilation of the implanted Melody valve in 17 (median 4.9 years [quartile 1 to quartile 3: 4.0 to 6.0 years] after TPVR), and bare-metal stent placement alone in 1 (4.4 years after TPVR). There were no major procedural complications. Overall, 4-year freedom from explant and from any later RVOT reintervention after the first reintervention were 83% and 60%, respectively. Freedom from repeat RVOT reintervention was longer in patients undergoing TPV-in-TPV than balloon dilation (71% vs. 46% at 4 years; p = 0.027). CONCLUSIONS: TPV-in-TPV can be an effective and durable treatment for Melody valve dysfunction. Although balloon dilation of the Melody valve was also acutely effective at reducing RVOT obstruction, the durability of this therapy was limited in this cohort compared with TPV-in-TPV.

Safety and Outcomes of Transcatheter Closure of Patent Ductus Arteriosus in Children With Pulmonary Artery Hypertension.

To investigate whether transcatheter device closure of patent ductus arteriosus (PDA) is safe in children with pulmonary artery hypertension, we retrospectively analyzed our experience with 33 patients who underwent the procedure from January 2000 through August 2015. Pulmonary artery hypertension was defined as a pulmonary vascular resistance index (PVRI) >3 WU · m2. All 33 children (median age, 14.5 mo; median weight, 8.1 kg) underwent successful closure device implantation and were followed up for a median of 17.2 months (interquartile range [IQR], 1.0-63.4 mo). During catheterization, the median PVRI was 4.1 WU · m2 (IQR, 3.6-5.3 WU · m2), and the median mean pulmonary artery pressure was 38.0 mmHg (IQR, 25.5-46.0 mmHg). Premature birth was associated with pulmonary vasodilator therapy at time of PDA closure ( P=0.001) but not with baseline PVRI (P=0.986). Three patients (9.1%) had device-related complications (one immediate embolization and 2 malpositions). Two of these complications involved embolization coils. Baseline pulmonary vasodilator therapy before closure was significantly associated with intensive care unit admission after closure (10/12 [83.3%] with baseline therapy vs 3/21 [14.3%] without; P <0.001). Of 11 patients receiving pulmonary vasodilators before closure and having a device in place long-term, 8 (72.7%) were weaned after closure (median, 24.0 mo [IQR, 11.0-25.0 mo]). We conclude that transcatheter PDA closure can be performed safely in many children with pulmonary artery hypertension and improve symptoms, particularly in patients born prematurely. Risk factors for adverse outcomes are multifactorial, including coil use and disease severity. Multicenter studies in larger patient populations are warranted.

Association between patient age at implant and outcomes after transcatheter pulmonary valve replacement in the multicenter Melody valve trials.

OBJECTIVES: To investigate whether age and valve size at implant contribute to outcomes after Melody transcatheter pulmonary valve replacement (TPVR). BACKGROUND: Patient age and valve size at implant contribute to longevity of surgical pulmonary valves. METHODS: All patients discharged with a Melody valve in the pulmonary position, as part of three prospective Melody valve multicenter studies, comprised the study cohort. Acute and time-related outcomes were analyzed according to age: children (≤12 years), adolescents (13-18 years), young adults (19-29 years), and older adults (≥30 years). RESULTS: Successful Melody valve implantation occurred in 49 children, 107 adolescents, 96 young adults, and 57 older adults. Pediatric patients (≤18 years) were more likely to have TPVR for conduit stenosis than adults (62% vs. 44%); children had the smallest conduits. After TPVR, pediatric and adult patients had similar decreases in right ventricular (RV) size by MRI, but adults had improved percentage predicted peak VO2 (58% preimplant to 64% postimplant, p = .02) and FEV1 (69% pre to 71% post, p = .005). Younger age was associated with shorter freedom from RVOT dysfunction, reintervention, and explant. Children had the shortest freedom from endocarditis (p = .041), but all other groups had 5-year freedom from endocarditis of ≥90%. CONCLUSIONS: Younger age was associated with shorter time to RVOT dysfunction, reintervention, and explant after Melody TPVR. Patients ≥13 years of age were at low risk for endocarditis and explant to 5 years. A better understanding of time-related outcomes by age will aid in the comparison of therapeutic options for TPVR candidates. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT00740870 (NCT00740870), https://clinicaltrials.gov/ct2/show/NCT01186692 (NCT01186692), and https://clinicaltrials.gov/ct2/show/NCT00688571 (NCT00688571).

Percutaneous balloon atrial septostomy on top of venoarterial extracorporeal membrane oxygenation results in safe and effective left heart decompression.

BACKGROUND: Transcatheter techniques are emerging for left atrial (LA) decompression under venoarterial extracorporeal membrane oxygenation (VA-ECMO). We aimed to assess whether balloon atrioseptostomy (BAS) is a safe and efficient strategy. METHODS: All patients who underwent percutaneous static BAS under VA-ECMO at four tertiary institutions were retrospectively reviewed. RESULTS: From 2000 to 2014, BAS was performed in 64 patients (32 adults and 32 children). Indications for ECMO support included acute myocarditis (31.3%) and non-myocarditis cardiac disease, mostly end-stage dilated cardiomyopathy (32.8%). BAS was required because of pulmonary oedema/haemorrhage and left ventricular (LV) distension. The mean balloon diameter was 21.8 ± 8.4mm. Adequate LA decompression was achieved in all patients. Mean LA pressure fell from 24.2 ± 6.9 mmHg to 7.8 ± 2.6 mmHg ( p < 0.001). The left-to-right atrial pressure gradient fell from 17.2 ± 7.1 mmHg to 0.09 ± 0.5 mmHg ( p < 0.001). Echocardiography showed an unrestrictive left-to-right atrial shunting in all patients. Improvement of day 1 chest X-ray was observed in 76.6% of patients, clinical status in 98.4% of patients and pulmonary haemorrhage in 14 out of 14 patients. Complications occurred in 9.4% of patients, representing pericardial effusion, fast atrial fibrillation, ventricular fibrillation requiring defibrillation, transient complete heart block and femoral venous dissection requiring covered stent placement. In the 37 (57.8%) patients who were successfully decannulated, the median ECMO duration was 9 (range: 4-24) days. After a median follow-up of 12.3 (range: 0.1-142) months, 35.9% patients died, 17.2% received a LV assist device as a bridge to transplantation, 31.2% were transplanted and 56.2% were home discharged and alive. CONCLUSIONS: Percutaneous BAS may be a safe and efficient strategy for discharging the LA in both adults and children supported by VA-ECMO.

P2Y12 Receptor Function and Response to Cangrelor in Neonates With Cyanotic Congenital Heart Disease.

Shunt thrombosis remains a major cause of morbidity and mortality, especially during the initial palliation for single-ventricle physiology. The authors present evidence that the P2Y12 inhibitor cangrelor may fill a therapeutic void in thromboprophylaxis. They base this theory on results showing that platelets from neonatal patients with cyanotic congenital heart disease have a robust response to adenosine diphosphate and are amenable to P2Y12 inhibition with cangrelor. Unique to this study was their ability to establish drug efficacy in an avatar mouse model that permits the in vivo evaluation of human platelet-mediated thrombus formation illustrating that this P2Y12 inhibitor yields the intended biological response.

Cardiac Catheterization in Pediatric Patients Supported by Extracorporeal Membrane Oxygenation: A 15-Year Experience.

Cardiac catheterization is commonly performed in patients being supported by extracorporeal membrane oxygenation (ECMO). We aimed to evaluate the safety, benefit, and outcomes of catheterization in pediatric patients supported by ECMO. Retrospective review of cardiac catheterizations performed in patients ≤18 years of age while on ECMO at a large tertiary care center between January 2000 and May 2015. A total of 55 catheterizations were performed on 51 patients during 53 unique ECMO courses. Indications for ECMO include ventricular dysfunction (22), cardiac arrest (20), inability to wean from cardiopulmonary bypass (7), and persistent cyanosis (4). Catheterizations included purely diagnostic studies (11), atrial septostomies (34), stenting of vessels or surgical shunts (6), adjustment of a stent (1), coil embolization (1), and endomyocardial biopsy (1). Septostomy was elective in 58.8% of cases (20) and emergent in 41.2% (14). Forty-six catheterizations had either surgical or catheter intervention during the same or subsequent study (83.6%). High severity complications occurred in three patients (5.6%), including one death due to hemothorax after pulmonary artery stent placement. There were no complications during patient transport. In total, 38 out of 53 (71.7%) ECMO courses resulted in decannulation, 29 (54.7%) patients survived to discharge from the hospital, and 25 (47.2%) were alive at follow-up. Cardiac catheterization can be safely performed on patients supported by ECMO. Cardiac catheterization is a critical tool in the early recognition, diagnosis, and direct treatment of hemodynamic/anatomic abnormalities in patients supported by ECMO.

Is Endomyocardial Biopsy a Safe and Useful Procedure in Children with Suspected Cardiomyopathy?

Endomyocardial biopsy (EMB) is a common procedure used to aid in the diagnosis, prognosis and treatment of suspected pediatric cardiomyopathy. In suspected cardiomyopathy, no multicenter experience has previously reported on the safety and utility of EMBs. Retrospectively, adverse event (AE) and patient and procedural characteristics were obtained at seven institutions participating in the Congenital Cardiac Catheterization Outcomes Project for both a cardiomyopathy (n = 158) and a post-transplant surveillance (n = 2665) cohort. Descriptive information regarding biopsy indication, pathology and clinical management based on EMB findings were retrospectively obtained. High-severity AEs were more common in the cardiomyopathy cohort when compared to the post-transplant surveillance cohort. The cardiomyopathy cohort was younger, more hemodynamically vulnerable and required more cardiorespiratory support during the procedure. The eight high-severity AEs in the cardiomyopathy group included one myocardial perforation, two ECMO cannulations and three deaths following the EMB. Factors associated with high-severity AEs included performing another catheter-based intervention during the EMB and longer fluoroscopy time. Notably, an increased number of biopsy attempts did not increase the risk of an AE. Suspected myocarditis was the most common indication. Diagnostic EMB pathology and thus alteration to clinical management based on pathology occurred more frequently in patients with suspected myocarditis. In conclusion, there is an increased incidence of high-severity AEs in patients undergoing EMB for suspected cardiomyopathy. EMB may be more clinically useful in the management of suspected myocarditis. The increased risk of high-severity AEs when additional interventions are performed highlights the hemodynamic vulnerability in patients with suspected cardiomyopathy.

Maladaptive aortic properties after the Norwood procedure: An angiographic analysis of the Pediatric Heart Network Single Ventricle Reconstruction Trial.

OBJECTIVES: Aortic arch reconstruction in children with single ventricle lesions may predispose to circulatory inefficiency and maladaptive physiology leading to increased myocardial workload. We sought to describe neoaortic anatomy and physiology, risk factors for abnormalities, and impact on right ventricular function in patients with single right ventricle lesions after arch reconstruction. METHODS: Prestage II aortic angiograms from the Pediatric Heart Network Single Ventricle Reconstruction trial were analyzed to define arch geometry (Romanesque [normal], crenel [elongated], or gothic [angular]), indexed neoaortic dimensions, and distensibility. Comparisons were made with 50 single-ventricle controls without prior arch reconstruction. Factors associated with ascending neoaortic dilation, reduced distensibility, and decreased ventricular function on the 14-month echocardiogram were evaluated using univariate and multivariable logistic regression. RESULTS: Interpretable angiograms were available for 326 of 389 subjects (84%). Compared with controls, study subjects more often demonstrated abnormal arch geometry (67% vs 22%, P < .01) and had increased ascending neoaortic dilation (Z score 3.8 ± 2.2 vs 2.6 ± 2.0, P < .01) and reduced distensibility index (2.2 ± 1.9 vs 8.0 ± 3.8, P < .01). Adjusted odds of neoaortic dilation were increased in subjects with gothic arch geometry (odds ratio [OR], 3.2 vs crenel geometry, P < .01) and a right ventricle-pulmonary artery shunt (OR, 3.4 vs Blalock-Taussig shunt, P < .01) but were decreased in subjects with aortic atresia (OR, 0.7 vs stenosis, P < .01) and those with recoarctation (OR, 0.3 vs no recoarctation, P = .04). No demographic, anatomic, or surgical factors predicted reduced distensibility. Neither dilation nor distensibility predicted reduced right ventricular function. CONCLUSIONS: After Norwood surgery, the reconstructed neoaorta demonstrates abnormal anatomy and physiology. Further study is needed to evaluate the longer-term impact of these features.

Percutaneous coronary artery revascularization procedures in pediatric heart transplant recipients: A large single center experience.

OBJECTIVES: To describe our experience, at a large pediatric heart transplant center, with percutaneous coronary interventions (PCI) for cardiac allograft vasculopathy (CAV). BACKGROUND: CAV is a leading cause of late graft failure, mortality, and re-transplantation in pediatric heart transplant (HTx) recipients. Studies of PCI in adult patients have shown some short-term improvements, but no significant change in long-term outcomes. There are limited data on PCI for CAV in pediatric patients. We describe the largest single-center experience to date. METHODS: We performed a retrospective chart review of all pediatric HTx recipients who underwent PCI for a diagnosis of CAV from 2005 to 2014. RESULTS: Twenty-three procedures were performed in 13 patients, at a median age of 16.4 years (range 5.6-21.2) and median time from HTx to first PCI of 8.3 years (range 2.9-20.3). Three cases consisted of angioplasty alone, two cases had bare metal stents implanted, and the remaining 18 had drug-eluting stents implanted. There was acute procedural success in all but one case, and there was only one procedure-related complication (rebleeding from access site). During the follow-up interval (median 10.4 months, range 0.2-111.8), 7/13 patients had repeat PCI performed, two patients died (at 1.8 and 5.8 months post-PCI), and five were re-transplanted (range 0.2-18 months post-PCI). Freedom from death or retransplant by Kaplan-Meier analysis was 54% at 1 year. CONCLUSIONS: PCI can be performed safely and effectively in pediatric HTx recipients with CAV. Similar to the adult experience, there remains a high rate of disease progression and graft failure. © 2016 Wiley Periodicals, Inc.

Aortic Root Distortion and Aortic Insufficiency During Balloon Angioplasty of the Right Ventricular Outflow Tract Prior to Transcatheter Pulmonary Valve Replacement.

OBJECTIVE: To describe the significance of aortic root distortion (AD) and/or aortic valve insufficiency (AI) during balloon angioplasty of the right ventricular outflow tract (RVOT) performed to rule out coronary artery compression prior to transcatheter pulmonary valve (TPV) implantation. METHODS: AD/AI was assessed by retrospective review of all procedural aortographies performed to evaluate coronary anatomy prior to TPV implantation. AD/AI was also reviewed in all pre-post MPV implant echocardiograms to assess for progression. RESULTS: From 04/2007 to 3/2015, 118 pts underwent catheterization with intent for TPV implant. Mean age and weight were 24.5 ± 12 years and 64.3 ± 20 kg, respectively. Diagnoses were: TOF (53%), D-TGA/DORV (18%), s/p Ross (15%), and Truncus (9%). Types of RV-PA connections were: conduits (96), bioprosthetic valves (14), and other (7). Successful TPV implant occurred in 91 pts (77%). RVOT balloon angioplasty was performed in 43/118 pts (36%). Aortography was performed in 18/43 pts with AD/AI noted in 6/18 (33%); 2 with D-TGA (1 s/p Lecompte, 1 s/p Rastelli), 2 with TOF, 1 Truncus and 1 s/p Ross. Procedure was aborted in the 2 who developed severe AD/AI. TPV was implanted in 3/4 patients with mild AD/AI. Review of pre-post TPV implantation echocardiograms in 83/91 pts (91%) revealed no new/worsened AI in any patient. CONCLUSION: AD/AI is relatively common on aortography during simultaneous RVOT balloon angioplasty. Lack of AI progression by echocardiography post-TPV implant suggests these may be benign findings in most cases. However, AD/AI should be carefully evaluated in certain anatomic subtypes with close RVOT/aortic alignments.

Balloon valvuloplasty for congenital aortic stenosis: Multi-center safety and efficacy outcome assessment.

OBJECTIVE: To describe contemporary outcomes of balloon aortic valvuloplasty (BAVP) performed in 22 US centers. BACKGROUND: BAVP constitutes first-line therapy for congenital aortic stenosis (cAS) in many centers. METHODS: We used prospectively-collected data from two active, multi-institutional, pediatric cardiac catheterization registries. Acute procedural success was defined, for purposes of this review, as a residual peak systolic gradient≤35 mm Hg and no more than mild aortic regurgitation (AR) for patients with isolated cAS. For patients with mixed aortic valve disease, a residual peak systolic gradient≤35 mm Hg without worsening of AR was considered successful outcome. RESULTS: In 373 patients with a median age of 8 months (1 day to 40 years of age) peak systolic gradient had a median of 59 [50, 71] mm Hg pre-BAVP and 22 [15, 30] mm Hg post-BAVP (P<0.001). Procedural success was achieved in 160 patients (71%). The factors independently associated with procedural success were: first time intervention (OR=2.0 (1.0, 4.0) P=0.04), not-prostaglandin dependent, (OR=3.5 (1.5, 8.1); P=0.003), and isolated cAS (absence of AR) (OR=2.1 (1.1-3.9); P=0.03). Twenty percent of patients experienced adverse events, half of which were of high severity. There was no procedural mortality. Neonatal status was the only factor associated with increased risk of high severity adverse events (OR 3.7; 95% CI 1.5-9.0). CONCLUSION: In the current era, BAVP results in procedural success (gradient reduction with minimal increase in AR) in 71% of patients treated at US centers where BAVP is considered first-line therapy relative to surgery.

The wedding cake solution: A percutaneous correction of a form fruste superior sinus venosus atrial septal defect.

We present the case of a patient with a superior sinus venosus defect (SSVD), with the atypical finding of an intact atrial septum and posterior atrial wall, which underwent percutaneous closure in the cardiac catheterization laboratory for repair. SSVDs are rare congenital cardiac anomalies, but when the anatomy is amenable to percutaneous strategies, a collaborative and creative approach can result in a safe and effective result.

Clinical and hemodynamic outcomes up to 7 years after transcatheter pulmonary valve replacement in the US melody valve investigational device exemption trial.

BACKGROUND: Studies of transcatheter pulmonary valve (TPV) replacement with the Melody valve have demonstrated good short-term outcomes, but there are no published long-term follow-up data. METHODS AND RESULTS: The US Investigational Device Exemption trial prospectively enrolled 171 pediatric and adult patients (median age, 19 years) with right ventricular outflow tract conduit obstruction or regurgitation. The 148 patients who received and were discharged with a TPV were followed up annually according to a standardized protocol. During a median follow-up of 4.5 years (range, 0.4-7 years), 32 patients underwent right ventricular outflow tract reintervention for obstruction (n=27, with stent fracture in 22), endocarditis (n=3, 2 with stenosis and 1 with pulmonary regurgitation), or right ventricular dysfunction (n=2). Eleven patients had the TPV explanted as an initial or second reintervention. Five-year freedom from reintervention and explantation was 76±4% and 92±3%, respectively. A conduit prestent and lower discharge right ventricular outflow tract gradient were associated with longer freedom from reintervention. In the 113 patients who were alive and reintervention free, the follow-up gradient (median, 4.5 years after implantation) was unchanged from early post-TPV replacement, and all but 1 patient had mild or less pulmonary regurgitation. Almost all patients were in New York Heart Association class I or II. More severely impaired baseline spirometry was associated with a lower likelihood of improvement in exercise function after TPV replacement. CONCLUSIONS: TPV replacement with the Melody valve provided good hemodynamic and clinical outcomes up to 7 years after implantation. Primary valve failure was rare. The main cause of TPV dysfunction was stenosis related to stent fracture, which was uncommon once prestenting became more widely adopted. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00740870.

Balloon atrial septostomy in pulmonary arterial hypertension: effect on survival and associated outcomes.

BACKGROUND: Pulmonary arterial hypertension (PAH) is a progressive disease that, without early identification and treatment, may lead to right heart failure, multi-organ dysfunction and early death. In severe PAH, in addition to maximal medical therapy, balloon atrial septostomy (BAS) may be used for palliation and as a bridge to lung transplantation. We present our contemporary institutional experience utilizing BAS in adult and pediatric patients with severe PAH. METHODS: We performed a retrospective analysis of 46 BASs performed in 32 patients with PAH from 2002 to 2013. Data obtained included vital status, functional class, medications, hemodynamic measurements from right heart catheterizations and biomarkers. Lung transplantation-free and repeat-BAS-free survival was analyzed. RESULTS: Median age at BAS was 23 (range 1 to 56) years. The most common indications were symptomatic right heart failure (21 of 46 patients) and pre-syncope/syncope (19 of 46 patients); 69% of patients were WHO Functional Class III or IV pre-BAS. There were no procedural complications or deaths. There were no significant differences in biomarkers or hemodynamic findings between pre-BAS and 1 year or latest follow-up. Seven patients were successfully bridged to lung transplantation. Lung transplantation-free and repeat-BAS-free survival at 30 days, 1 year and 5 years was 87%, 61% and 32%, respectively. CONCLUSIONS: In our experienced center, BAS was shown to be safe in patients with severe PAH on maximal medical management, with no procedural deaths or complications. BAS was safely used as a bridge to lung transplantation or to alleviate right heart failure symptoms and/or syncope. Other potential benefits for end-organ function and overall survival remain to be determined.