Extravascular protrusion of the Alterra adaptive prestent identified on surveillance computed tomography imaging.

BACKGROUND: The Alterra adaptive prestent is a novel self-expanding device designed to provide a landing zone for the 29 mm SAPIEN 3 valve to treat pulmonary regurgitation in patients with a right ventricular outflow tract that is too large for a balloon expandable valve alone. The mechanism of fixation for the Alterra prestent is radial force from the self-expanding stent frame, combined with a unique set of flared "tines" that protrude from both ends of the stent. AIMS, METHODS, AND RESULTS: In this report, we describe 6 patients who underwent uncomplicated transcatheter pulmonary valve replacement with an Alterra adaptive prestent and SAPIEN 3 valve and had surveillance chest computed tomography (CT) scans performed 1 day to 21 months after implant. In each patient, the CT scan demonstrated extravascular extension of a portion of the Alterra prestent, without clinical sequelae, but with extension into the ascending aorta in 1 patient and contact with the ascending aorta, left pulmonary vein, or left atrial appendage in 3 others. CONCLUSIONS: Surveillance CT imaging shows that the Alterra prestent can perforate the pulmonary artery and/or right ventricle. Although no sequelae were seen in these patients, prestent perforation has the potential to be clinically important. Implanters should be aware of this finding and its potential implications. As experience with the Alterra prestent grows, it will be important to further define the risk factors, incidence, and implications of this phenomenon.

Right ventricular outflow tract obstruction associated with neointimal tissue accumulation and distortion of the Harmony TPV25 stent frame: Potential mechanisms and treatment.

BACKGROUND: The Harmony TPV25 transcatheter pulmonary valve (Medtronic Inc.) is constructed with a self-expanding stent frame comprising six zigged nitinol wires sewn together and covered with knitted polyester fabric, with flared inflow and outflow ends and a porcine pericardial valve sutured to the central portion of the device. It was approved for treatment of pulmonary regurgitation after prior right ventricular outflow tract repair in 2021. Early outcomes of this procedure have been excellent, but little is known about valve durability or ultimate mechanisms of dysfunction. METHODS: We collected data on patients who underwent reintervention for TPV25 dysfunction and described findings related to distortion of the stent frame and tissue accumulation. RESULTS: We describe six patients who underwent valve-in-valve implant for TPV25 obstruction (peak catheterization gradient peak 28-73 mmHg) 10-28 months after implant. In all cases, there was tissue accumulation within the inflow and valve-housing segments of the device and deformation of the self-expanding valve frame characterized by variable circumferential narrowing at the junction between the valve housing and the inflow and outflow portions of the device, with additional geometric changes in all segments. All six patients underwent valve-in-valve implant that results in a final peak gradient ≤10 mmHg and no regurgitation. DISCUSSION: The occurrence of short-term Harmony TPV25 dysfunction in multiple patients with a similar appearance of frame distortion and tissue accumulation within the inflow and valve housing portions of the device suggests that this may be an important failure mechanism for this valve. Potential causes of the observed findings are discussed. It is possible to treat this mechanism of TPV25 dysfunction with valve-in-valve implant using balloon expandable transcatheter valves.

Safety and Short-Term Outcomes for Infants < 2.5 kg Undergoing PDA Device Closure: A C3PO Registry Study.

To evaluate short-term procedural outcomes and safety for infants < 2.5 kg who underwent catheterization with intended patent ductus arteriosus (PDA) device closure in a multi-center registry, as performance of this procedure becomes widespread. A multi-center retrospective review was performed using data from the Congenital Cardiac Catheterization Project on Outcomes (C3PO) registry. Data were collected for all intended cases of PDA closure in infants < 2.5 kg from April 2019 to December 2020 at 13 participating sites. Successful device closure was defined as device placement at the conclusion of the catheterization. Procedural outcomes and adverse events (AE) were described, and associations between patient characteristics, procedural outcomes and AEs were analyzed. During the study period, 300 cases were performed with a median weight of 1.0 kg (range 0.7-2.4). Successful device closure was achieved in 98.7% of cases with a 1.7% incidence of level 4/5 AEs, including one periprocedural mortality. Neither failed device placement nor adverse events were significantly associated with patient age, weight or institutional volume. Higher incidence of adverse events associated with patients who had non-cardiac problems (p = 0.017) and cases with multiple devices attempted (p = 0.064). Transcatheter PDA closure in small infants can be performed with excellent short-term outcomes and safety across institutions with variable case volume.

Interpreting Quality Improvement When Introducing New Technology: A Collaborative Experience in ASD Device Closures.

The objective of this study was to evaluate the impact of the regular introduction of new technologies into interventional cardiac catheterization procedures, in this case new atrial septal defect (ASD) closure devices, while conducting a multi-center collaborative initiative to reduce radiation usage during all procedures. Data were collected prospectively by 8 C3PO institutions between January 1, 2014 and December 31, 2017 for ASD device closure procedures in the cardiac catheterization lab during a quality improvement (QI) initiative aimed at reducing patient radiation exposure. Radiation exposure was measured in dose area product per body weight (µGy*m2/kg). Use of proposed practice change strategies at the beginning and end of the QI intervention period was assessed. Radiation exposure was summarized by institution and by initial type of device used for closure. This study included 602 ASD device closures. Without changes in patient characteristics, total fluoroscopy duration, or number of digital acquisitions, median radiation exposure decreased from 37 DAP/kg to 14 DAP/kg from 2014 to 2017. While all individual centers decreased overall median DAP/kg, the use of novel devices for ASD closure correlated with a temporary period of worsening institutional radiation exposure and increased fluoroscopy time. The introduction of new ASD closure devices resulted in increased radiation exposure during a QI project designed to reduce radiation exposure. Therefore, outcome assessment must be contextualized in QI projects, hospital evaluation, and public reporting, to acknowledge the expected variation during innovation and introduction of novel therapies.

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.

Surgical Versus Percutaneous Closure of PDA in Preterm Infants: Procedural Charges and Outcomes.

BACKGROUND: Studies comparing percutaneous closure of patent ductus arteriosus (PDA) with surgical ligation tend to exclude premature infants and have not assessed procedural charges. We compared our contemporary outcomes and charges of device closure to surgical ligation of PDA in preterm infants. MATERIAL AND METHODS: Preterm infants who underwent isolated PDA closure during their newborn hospitalization (January 2014 to September 2017) were grouped based on intention to treat (surgery versus device closure). Patient demographics, procedural details, and immediate postprocedural outcomes were compared. Procedural charges for device closure versus surgical ligation were compared. RESULTS: Compared with the device group (n = 33), patients undergoing surgical ligation (n = 39) were younger, smaller, and required more preoperative support (P < 0.05). The procedure time was shorter for surgical ligation (P < 0.01). Although there was no procedural mortality in either group, the complication rate was higher for device closure than for surgical ligation (15.2% versus 0%; P = 0.02). The proportion of patients returning to preprocedural respiratory support by 48 h after procedure was similar. There was a higher proportion of surgical patients who required increased inotropic support in the first 24 h after procedure (P = 0.19). The procedural charges for transcatheter device closure were twice as expensive as those for surgical ligation. CONCLUSIONS: In our early experience with percutaneous PDA closure, we found a percutaneous approach in preterm infants feasible and well tolerated. Both surgical ligation and device closure were associated with perioperative or postoperative complications. Procedural charges were higher for percutaneous closure, driven by device charge and catheterization room utilization. Further investigation is needed to establish guidelines for first-line therapy for PDA closure in preterm infants, including cost-benefit analysis.

Percutaneous transcatheter pulmonary valve replacement in children weighing less than 20 kg.

BACKGROUND: Since FDA approval of the Melody valve, transcatheter pulmonary valve replacement (TPVR) has been offered to an expanding population. Limited data exist regarding the safety and feasibility of TPVR in smaller patients. METHODS: All patients weighing <20 kg who underwent catheterization for percutaneous TPVR at four centers were reviewed. RESULTS: Of the 51 patients reviewed, 43 (84%) had successful valve implantation and 8 (16%) were found not to be candidates due to access veins too small (n = 3), coronary artery/aortic root compression (n = 3), and RVOT too large (n = 2). The 43 patients who underwent successful percutaneous TPVR had a median age and weight of 5.8 years (3.3-10) and 17.7 kg (13.5-19.8), and most had tetralogy of Fallot (TOF). TPVR was performed via femoral vein (FV) access in 24 patients and internal jugular vein (IJV) access in 19 patients. Median weight in patients with IJV implant was 1.1 kg lower than those who underwent transfemoral implant (17.0 vs. 18.1 kg, P = 0.05). There were four adverse events: one iliac vein injury, one contained MPA tear, and two patients with post-procedure femoral vein bleeding. All patients were alive at recent follow-up, a median of 2.0 years (0.1-6.0) after TPVR. There was excellent valve function with mean Doppler gradients of 3-20 mm Hg, and trivial or mild pulmonary regurgitation in all but one patient. There were no RVOT reinterventions and no cases of endocarditis. CONCLUSIONS: Percutaneous TPVR can be safely performed in patients <20 kg. The procedure frequently requires IJV access, and access site/bleeding complications may be more common in this cohort.

Circulatory support using the impella device in fontan patients with systemic ventricular dysfunction: A multicenter experience.

BACKGROUND: There are limited mechanical circulatory support options for patients with single ventricle (SV) anatomy. This is a multicenter, retrospective study of the Impella pump to support the systemic ventricle in a cohort of SV patients with Fontan circulation. METHODS: Patients with SV anatomy supported with an Impella device from 2012 to 2015 were included. Demographic information, indication for support, adverse events and short-term outcome data were collected. RESULTS: Ten patients were included. The median age and weight at implant was 26 years (4-38 years) and 64 kg (15-102 kg). Indications for support were systemic ventricular failure with cardiogenic shock (n = 8) or high-risk electrophysiology (EP) procedures (n = 2). The median duration of support was 49 hr (2.7-264 hr). Support was discontinued for ventricular recovery in five patients, transition to another device in two patients, completion of EP procedure in two patients and death in one patient. Survival to hospital discharge was 80%. Adverse events occurred in 4 patients. There were two cases of hemolysis, one case of increasing aortic valve insufficiency with implant and one asymptomatic access site thrombus. There were no bleeding or thromboembolic events. CONCLUSIONS: Impella devices can provide temporary support for the systemic ventricle in SV patients as a bridge to recovery or additional device. Procedural survival and adverse event profiles are favorable. © 2017 Wiley Periodicals, Inc.

Radiation Exposure by Three-Dimensional Rotational Angiography (3DRA) During Trans-catheter Melody Pulmonary Valve Procedures (TMPV) in a Pediatric Cardiac Catheterization Laboratory.

This retrospective study aims to evaluate radiation exposure by three-dimensional rotational angiography (3DRA) during trans-catheter Melody pulmonary valve (TMPV) procedures. 3DRA has been reported to have added value in the management of complex congenital heart disease aiding in the performance of interventional procedures albeit with concerns of higher radiation exposure. We test the hypothesis that 3DRA does not cause additional radiation exposure during TMPV procedures. We analyzed all 81 TMPV procedures performed at St. Louis Children's Hospital, MO, USA, from January 1, 2011 to December 31, 2014. Dose-area product (DAP), DAP indexed to body weight (DAP/BW), fluoroscopy time (FT), and weight-fluoroscopy time product of each procedure were recorded. We reviewed each procedure's images to determine whether additional interventions were performed (e.g., pulmonary artery angioplasty or treatment of conduit pseudo-aneurysm). 3DRA was used in 36 % of the procedures. 3DRA group had a higher number of additional procedures performed. The 3DRA group did not differ from the non-3DRA group in DAP, DAP/BW, and weight-fluoroscopy time product. 3DRA does not cause greater radiation exposure during TMPV procedures.

Incidence and management of life-threatening adverse events during cardiac catheterization for congenital heart disease.

Continued advancements in congenital cardiac catheterization and interventions have resulted in increased patient and procedural complexity. Anticipation of life-threatening events and required rescue measures is a critical component to preprocedural preparation. We sought to determine the incidence and nature of life-threatening adverse events in congenital and pediatric cardiac catheterization, risk factors, and resources necessary to anticipate and manage events. Data from 8905 cases performed at the 8 participating institutions of the Congenital Cardiac Catheterization Project on Outcomes were captured between 2007 and 2010 [median 1,095/site (range 133-3,802)]. The incidence of all life-threatening events was 2.1 % [95 % confidence interval (CI) 1.8-2.4 %], whereas mortality was 0.28 % (95 % CI 0.18-0.41 %). Fifty-seven life-threatening events required cardiopulmonary resuscitation, whereas 9 % required extracorporeal membrane oxygenation. Use of a risk adjustment model showed that age <1 year [odd ratio (OR) 1.9, 95 % CI 1.4-2.7, p < 0.001], hemodynamic vulnerability (OR 1.6, 95 % CI 1.1-2.3, p < 0.01), and procedure risk (category 3: OR 2.3, 95 % CI 1.3-4.1; category 4: OR 4.2, 95 % CI 2.4-7.4) were predictors of life-threatening events. Using this model, standardized life-threatening event ratios were calculated, thus showing that one institution had a life-threatening event rate greater than expected. Congenital cardiac catheterization and intervention can be performed safely with a low rate of life-threatening events and mortality; preprocedural evaluation of risk may optimize preparation of emergency rescue and bailout procedures. Risk predictors (age < 1, hemodynamic vulnerability, and procedure risk category) can enhance preprocedural patient risk stratification and planning.

Left main coronary artery dissection in pediatric sport-related chest trauma.

BACKGROUND: Traumatic coronary artery dissection (CAD) after blunt chest trauma (BCT) is extremely rare, particularly in children. Among coronary dissections, left main coronary artery (LMCA) dissection is the least common, with only two pediatric cases reported previously. Manifestations of coronary dissections can range from ST segment changes to sudden death. However, these manifestations are not specific and can be present with other cardiac injuries. To our knowledge we present the first pediatric case of traumatic LMCA dissection after sport-related BCT that was treated successfully with coronary stenting. CASE REPORT: A 14-year-old child sustained BCT during a baseball game. Early in the clinical course, he had episodes of ventricular dysrhythmias, diffuse ST changes, rising troponin I, and hemodynamic instability. Emergent cardiac catheterization revealed an LMCA dissection with extension into the proximal left anterior descending artery (LADA). A bare metal stent was placed from the LMCA to the LADA, which improved blood flow through the area of dissection. He has had almost full recovery of myocardial function and has been managed as an outpatient with oral heart failure and antiplatelet medications. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Our case highlights that CAD, although rare, can occur after pediatric BCT. Pediatric emergency responders must have a heightened awareness that evidence of ongoing myocardial ischemia, such as evolving and focal myocardial infarction on electrocardiogram, persistent elevation or rising troponin I, and worsening cardiogenic shock, can represent a coronary event and warrant further evaluation. Cardiac catheterization can be both a diagnostic and therapeutic modality in such cases. Early recognition and management is vital for myocardial recovery.

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

BACKGROUND: Anatomic selection for Harmony valve implant is determined with the aid of a screening report and perimeter plot (PP) that depicts the perimeter-derived radius along the right ventricular outflow tract (RVOT) and projects device oversizing. The PP provides an estimation of suitability for implant, but its sensitivity as a screening method is unknown. This study was performed to describe anatomic features and outcomes in patients who underwent Harmony TPV25 implant despite a PP that predicted inadequate oversizing. METHODS: We reviewed RVOT anatomic features and measurements in patients who underwent transcatheter pulmonary valve replacement with the Harmony TPV25 device despite a PP that predicted inadequate oversizing. RESULTS: This study included 22 patients. There were no unsuccessful implants or adverse valve-related events. Anatomic features varied, but all patients fit into 1 of 3 anatomic types characterized by differences in RVOT dimensions. Type 1 patients (n=9) had a long RVOT with a choke point and a wide main pulmonary artery. Type 2 patients (n=6) had a short RVOT that was pyramidal in shape, with no choke point, and extensive main pulmonary artery lengthening/expansion during systole. Type 3 patients (n=7) had a short, bulbous main pulmonary artery with a choke point and an open pulmonary artery bifurcation. CONCLUSIONS: Transcatheter pulmonary valve replacement with the Harmony valve is feasible in some patients whose PP fit analysis predicts inadequate oversizing. All cases in this series fit into 1 of 3 anatomic patterns, which are not identified in the screening report. Implanters must review cases individually to assess the feasibility of the implant.

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

BACKGROUND: Transcatheter pulmonary valve replacement (TPVR) with the self-expanding Harmony valve (Medtronic) is an emerging treatment for patients with native or surgically repaired right ventricular outflow tract (RVOT) pulmonary regurgitation (PR). Limited data are available since U.S. Food and Drug Administration approval in 2021. OBJECTIVES: In this study, the authors sought to evaluate the safety and short-term effectiveness of self-expanding TPVR in a real-world experience. METHODS: This was a multicenter registry study of consecutive patients with native RVOT PR who underwent TPVR through April 30, 2022, at 11 U.S. CENTERS: The primary outcome was a composite of hemodynamic dysfunction (PR greater than mild and RVOT mean gradient >30 mm Hg) and RVOT reintervention. RESULTS: A total of 243 patients underwent TPVR at a median age of 31 years (Q1-Q3: 19-45 years). Cardiac diagnoses were tetralogy of Fallot (71%), valvular pulmonary stenosis (21%), and other (8%). Acute technical success was achieved in all but 1 case. Procedural serious adverse events occurred in 4% of cases, with no device embolization or death. Hospital length of stay was 1 day in 86% of patients. Ventricular arrhythmia prompting treatment occurred in 19% of cases. At a median follow-up of 13 months (Q1-Q3: 8-19 months), 98% of patients had acceptable hemodynamic function. Estimated freedom from the composite clinical outcome was 99% at 1 year and 96% at 2 years. Freedom from TPVR-related endocarditis was 98% at 1 year. Five patients died from COVID-19 (n = 1), unknown causes (n = 2), and bloodstream infection (n = 2). CONCLUSIONS: In this large multicenter real-world experience, short-term clinical and hemodynamic outcomes of self-expanding TPVR therapy were excellent. Ongoing follow-up of this cohort will provide important insights into long-term outcomes.

Transcatheter ventricular septal defect (VSD) creation for restrictive VSD in double-outlet right ventricle.

BACKGROUND: Double-outlet right ventricle (DORV) with a restrictive ventricular septum is a rare but highly morbid phenomenon that can be complicated by progressive left ventricular hypertrophy, arrhythmias, aneurysm formation, severe pulmonary hypertension, and death in the newborn. Surgical creation or enlargement of a ventricular septal defect (VSD) is palliative but may damage the conduction system or the atrioventricular valves in the newborn. This report presents a transcatheter approach to palliation for a newborn that had DORV with a restrictive ventricular septum. METHODS/RESULTS: A full-term infant girl (2.9 kg) referred for hypoxia (80% with room air) and murmur was found to have DORV, interrupted inferior vena cava, and restrictive VSD (95-mmHg gradient). Transhepatic access was performed, and an internal mammary (IM) catheter was advanced through the atrial septal defect and into the left ventricle. By transesophageal echocardiographic guidance, a Baylis radiofrequency perforation wire was used to cross the ventricular septum, and the defect was enlarged using a 4-mm cutting balloon. A bare metal stent then was deployed to maintain the newly created VSD. The patient did well after the procedure but required pulmonary artery banding 4 days later. She returned 5 months later with cyanosis and the development of obstructing right ventricle muscle bundles, requiring further surgical palliation. CONCLUSIONS: This report describes the first transcatheter creation of VSD in DORV with a restrictive ventricular septum in a newborn infant. Use of the radiofrequency catheter in combination with cutting balloon dilation and stent implantation is an efficient method for creating a VSD in such a patient.

Percutaneous pulmonary valve implantation: fixing the problems and pushing the envelope.

PURPOSE OF REVIEW: A recent development within pediatric cardiology is percutaneous pulmonary valve implantation (PPVI). This has extended the life of surgical conduits and decreased the number of surgical procedures required. Early reports focused on feasibility and safety of the technique; recent literature has focused on avoidance of complications such as stent fractures and on expanding the procedure to nonconduit implantation. The purpose of this review is to summarize the recent data regarding stent fractures and alternative uses of the valve. RECENT FINDINGS: Stent fractures following PPVI are reported in 20-28% of patients. Prestenting has recently been shown to be protective and to extend the freedom from stent fractures. The use of PPVI has also been reported in nonconduit positions such as in bioprosthetic tricuspid valves, branch pulmonary arteries, aortic and mitral positions. In addition, the valve has been implanted in higher pressure environments. The short-term success in these applications appears to be quite good. SUMMARY: PPVI has allowed extension of the life of surgical conduits and failure of the valve is mainly related to stent fractures. Recent developments have minimized this complication. In addition, use of the valve has been extended to nontraditional locations and short-term results are favorable.

Cardiac Magnetic Resonance to Predict Coronary Artery Compression in Transcatheter Pulmonary Valve Implantation Into Conduits.

OBJECTIVES: The aim of this study was to evaluate the accuracy of cardiac magnetic resonance (CMR) in predicting coronary artery (CA) compression during transcatheter pulmonary valve implantation (TPVi). BACKGROUND: TPVi is a widely available option to treat dysfunctional right ventricle (RV)-to-pulmonary artery (PA) conduits, but CA compression is an absolute contraindication. CMR can evaluate coronary anatomy, but its utility in predicting CA compression is not well established. METHODS: After Institutional Review Board approval was obtained, all patients at 9 centers with attempted TPVi in RV-PA conduits and recent CMR (≤12 months) were analyzed. A core laboratory reviewed all CMR studies for the shortest orthogonal distance from a CA to the conduit, the shortest distance from a CA to the most stenotic area of the conduit, and subjective assessment of CA compression risk. RESULTS: Among 231 patients, TPVi was successful in 198 (86%); in 24 (10%), balloon testing precluded implantation (documented CA compression or high risk). Distance to the RV-PA conduit ≤2.1 mm (area under the curve [AUC]: 0.70) and distance to most stenotic area ≤13.1 mm (AUC: 0.69) predicted CA compression. Subjective assessment had the highest AUC (0.78), with 96% negative predictive value. Both distances and qualitative assessment remained independently associated with CA compression when controlling for abnormal coronary anatomy or degree of conduit calcification. CONCLUSIONS: CMR can help predict the risk for CA compression during TPVi in RV-PA conduits but cannot completely exclude CA compression. CMR may assist in patient selection and counseling families prior to TPVi, although balloon testing remains essential.

Defect closure in the lipomatous hypertrophied atrial septum with the Amplatzer muscular ventricular septal defect closure device: a case series.

Variations in the anatomy of the atrial septum can confound the transcatheter closure of atrial septal defects and patent foramen ovale. While lipomatous hypertrophy of the atrial septum is not frequently encountered, attempts to use standard atrial septal occlusion devices in such patient can lead to malapposition and continued shunt. Some operators have suggested that atrial septal hypertrophy is a relative contraindication to transcatheter-based closure techniques. We present a novel technique exploiting the features of the Amplatzer muscular ventricular septal defect occluder to treat atrial septal defects in the setting of lipomatous hypertrophy of the atrial septum in two patients.

Midterm outcomes of the Potts shunt for pediatric pulmonary hypertension, with comparison to lung transplant.

OBJECTIVE: For children with severe pulmonary hypertension, addition of Potts shunt to a comprehensive palliation strategy might improve the outcomes afforded by medications and delay lung transplantation. METHODS: A prospective analysis was conducted of all children undergoing Potts shunt (first performed in 2013) or bilateral lung transplant for pulmonary hypertension from 1995 to present. RESULTS: A total of 23 children underwent Potts shunt (20 surgical, 3 transcatheter), and 31 children underwent lung transplant. All children with Potts shunt had suprasystemic right ventricle pressures despite maximal medical treatment. In the majority of patients, the Potts shunt was performed through a left thoracotomy approach (90%, 18/20), by direct anastomosis (65%, 13/20), and without the use of extracorporeal support (65%, 13/20). Perioperative outcomes after Potts shunt were superior to lung transplant including mechanical ventilation time (1.3 vs 10.2 days, P = .019), median hospital length of stay (9.8 vs 34 days, P = .012), and overall complication rate (35% [7/20] vs 81% [25/31], P = .003). Risk factors for operative mortality after Potts shunt (20%, 4/20; compared with 6%, 2/31 for lung transplant, P = .195) included preoperative extracorporeal membrane oxygenation and significant right ventricle dysfunction. In midterm follow-up (median 1.8, maximum 6.1 years), patients with Potts shunt had durable equalization of right ventricle/left ventricle pressures and improved functional status. There was no significant survival difference in patients with Potts shunt and patients with lung transplant (P = .258). CONCLUSIONS: Potts shunt is an effective palliation for children with suprasystemic pulmonary hypertension that may become part of a strategy to maximize longevity and functional status for these challenging patients.

Transcatheter Pulmonary Valve Replacement With the Sapien Prosthesis.

BACKGROUND: There are limited published data focused on outcomes of transcatheter pulmonary valve replacement (TPVR) with either a Sapien XT or Sapien 3 (S3) valve. OBJECTIVES: This study sought to report short-term outcomes in a large cohort of patients who underwent TPVR with either a Sapien XT or S3 valve. METHODS: Data were entered retrospectively into a multicenter registry for patients who underwent attempted TPVR with a Sapien XT or S3 valve. Patient-related, procedural, and short-term outcomes data were characterized overall and according to type of right ventricular outflow tract (RVOT) anatomy. RESULTS: Twenty-three centers enrolled a total of 774 patients: 397 (51%) with a native/patched RVOT; 183 (24%) with a conduit; and 194 (25%) with a bioprosthetic valve. The S3 was used in 78% of patients, and the XT was used in 22%, with most patients receiving a 29-mm (39%) or 26-mm (34%) valve. The implant was technically successful in 754 (97.4%) patients. Serious adverse events were reported in 67 patients (10%), with no difference between RVOT anatomy groups. Fourteen patients underwent urgent surgery. Nine patients had a second valve implanted. Among patients with available data, tricuspid valve injury was documented in 11 (1.7%), and 9 others (1.3%) had new moderate or severe regurgitation 2 grades higher than pre-implantation, for 20 (3.0%) total patients with tricuspid valve complications. Valve function at discharge was excellent in most patients, but 58 (8.5%) had moderate or greater pulmonary regurgitation or maximum Doppler gradients >40 mm Hg. During limited follow-up (n = 349; median: 12 months), 9 patients were diagnosed with endocarditis, and 17 additional patients underwent surgical valve replacement or valve-in-valve TPVR. CONCLUSIONS: Acute outcomes after TPVR with balloon-expandable valves were generally excellent in all types of RVOT. Additional data and longer follow-up will be necessary to gain insight into these issues.

Biventricular assist devices as a bridge to heart transplantation in small children.

BACKGROUND: Experience with the use of biventricular assist device (BiVAD) support to bridge small children to heart transplantation is limited. METHODS AND RESULTS: We used BIVAD support (Berlin EXCOR) in 9 pediatric heart transplant candidates from 4/05 to 7/07. The median patient age was 1.7 years (12 days to 17 years). The median patient weight was 9.4 kg (3 to 38 kg). All children were supported with multiple intravenous inotropes+/-mechanical ventilation (6) or ECMO (3) before BiVAD implantation. All had significant right ventricular dysfunction. The median pulmonary vascular resistance index (Rpi) was 6.0 WU/m(2). Eight patients were successfully bridged to heart transplantation after a median duration of BiVAD support of 35 days (1 to 77 days). One death occurred after 10 days of support from perioperative renal failure in a 3 kg infant. Five patients required at least 1 blood pump change. One patient had a driveline infection requiring treatment. There were no acute neurological complications, no thromboembolic events, and no bleeding complications. In 2 patients with Rpi >10 WU/m(2) unresponsive to pulmonary vasodilator therapy, Rpi dropped to 1.4 and 4.6 WU/m(2), after 33 and 41 days of support, respectively. All 8 survivors underwent successful heart transplantation. Of 5 patients supported >30 days, 3 developed an extremely elevated (>90%) panel reactive antibody by ELISA that was not confirmed by other methods; none had a positive donor-specific retrospective crossmatch. There was 1 episode of rejection (with hemodynamic compromise) in the 8 transplanted patients. Rpi was normal (<3 WU/m(2)) without pulmonary vasodilators in all patients within 3 months after transplant. There have been no deaths after transplant with a median follow-up of 19 months. CONCLUSIONS: BiVAD support can effectively be used in small children as a bridge to heart transplantation and can be accomplished with low mortality and morbidity. BiVAD support may offer an additional means to reverse extremely elevated pulmonary vascular resistance. Surveillance for HLA antibody sensitization during BiVAD support may be complicated by the development of non-HLA antibodies which may not reflect true HLA presensitization.