The incidence of recurrent laryngeal nerve injury resulting in vocal cord paralysis following interventional congenital catheterisation procedures.

BACKGROUND: Recurrent laryngeal nerve injury leading to vocal cord paralysis is a known complication of cardiothoracic surgery. Its occurrence during interventional catheterisation procedures has been documented in case reports, but there have been no studies to determine an incidence. OBJECTIVE: To establish the incidence of left recurrent laryngeal nerve injury leading to vocal cord paralysis after left pulmonary artery stenting, patent ductus arteriosus device closure and the combination of the procedures either consecutively or simultaneously. METHODS: Members of the Congenital Cardiovascular Interventional Study Consortium were asked to perform a retrospective analysis to identify cases of recurrent laryngeal nerve injury after the aforementioned procedures. Twelve institutions participated in the analysis. They also contributed the total number of each procedure performed at their respective institutions for statistical purposes. RESULTS: Of the 1337 patients who underwent left pulmonary artery stent placement, six patients (0.45%) had confirmed vocal cord paralysis. 4001 patients underwent patent ductus arteriosus device closure, and two patients (0.05%) developed left vocal cord paralysis. Patients who underwent both left pulmonary artery stent placement and patent ductus arteriosus device closure had the highest incidence of vocal cord paralysis which occurred in 4 of the 26 patients (15.4%). Overall, 92% of affected patients in our study population had resolution of symptoms. CONCLUSION: Recurrent laryngeal nerve injury is a rare complication of left pulmonary artery stent placement or patent ductus arteriosus device closure. However, the incidence is highest in patients undergoing both procedures either consecutively or simultaneously. Additional research is necessary to determine contributing factors that might reduce the risk of recurrent laryngeal nerve injury.

Successful radiofrequency perforation and balloon decompression of cor triatriatum sinister using novel technique, a case series.

Cor triatriatum sinister (CTS) is a rare congenital cardiac anomaly representing <0.1% of all congenital cardiac malformations. It is characterized by the presence of a left atrial (LA) membrane that leads to left ventricular inflow obstruction. Uncorrected, obstructed CTS may have significant sequelae such as pulmonary hypertension or arrhythmias. Transcatheter balloon decompression has been described as a successful alternative to surgical resection of the obstructing membrane. Our review of the literature revealed no reported cases utilizing radiofrequency (RF) energy to perforate the CTS membrane prior to balloon decompression. This manuscript describes two patients with CTS who were treated successfully with a transcatheter technique using RF energy to perforate the obstructing membrane prior to balloon angioplasty and decompression of the LA.

Can a self-expanding pediatric stent expand with an artery? Relationship of stent design to vascular biology.

OBJECTIVES: A large-diameter, intravascular, self-expanding stent system capable of continued expansion during somatic and vascular growth was modeled with finite element analysis (FEA), manufactured and tested in an animal model. BACKGROUND: Children can quickly outgrow intravascular stents. If a stent could expand after implantation in arteries this would be ideal for use in pediatric patients. METHODS: Computer-aided design and FEA were used to design and manufacture large-diameter, self-expanding nitinol stents with both high and low chronic outward force (COF). Four distinct stents with similar designs but with variable lengths and strut thicknesses were manufactured. Fourteen of these stents were implanted in the abdominal aortas or iliac arteries of four juvenile swine. RESULTS: All animals survived without complication to their designated time points of harvest (90 or 180-days), and all stents expanded to greater diameters than the adjacent non-stented artery. Luminal diameter growth was 34-49% and 20-23% for stented and non-stented segments, respectively. Histologic examination revealed variable degrees of the internal elastic lamina and/or medial disruption with a mean injury score ranging from 0.70 ± 0.56 to 1.23 ± 0.21 and low COF stents implanted in smaller arteries having a larger injury score. Inflammatory responses and stenosis formation were minimal and ranged from 0.50 ± 0.71 to 3.00 ± 0.00 and 5.52 ± 1.05% to 14.68 ± 9.12%, respectively. The stent's COF did not correlate with vessel expansion or vascular injury. CONCLUSIONS: Self-expanding stents can mirror and even exceed somatic growth. Although longer-term testing is needed, it may be possible to custom tailor self-expanding stents to expand after arterial implantation in pediatric patients.

Mechanical properties of low-diameter balloon expandable covered stents.

OBJECTIVES: To determine over-dilation potential of commercially available covered stents. BACKGROUND: Covered stents including the Atrium iCast, Gore VBX, and Lifestream stents (LS) can treat ruptures, dissections, and aneurysms in small vessels. Especially in growing patients, stents often require serial dilations beyond their implant or nominal diameters. Tolerance of serial dilations is clinically important information for interventionalists. METHODS: Serial dilations of 5-12 mm iCast, VBX, and LS covered stents were performed in 1-2 mm increments (up to 20 mm). With each dilation, foreshortening and recoil were measured, and stent strut and covering integrity were assessed. High-pressure balloons were used to expand the stents until they fractured or could not be further expanded. RESULTS: The 5-8 mm LS tolerated dilation to 14.5-16 mm. The 10-12 mm LS stents tolerated dilation to 18 mm and fractured on the 20 mm balloon. LS stents foreshortened 35%-45% on average after 8 mm of over-dilation and had 5%-10% recoil on <6 mm over-dilation. All iCast stents tolerated dilation to 12-13 mm and required fracture for dilation to >14 mm. ICast stents foreshortened 19%-29% at maximum dilation, with 3-6% recoil on <2 mm over-dilation, and < 3% thereafter. VBX stents over-dilated to 2.9-4.7 mm above nominal, foreshortening 40%-50% after 4-6 mm of over-dilation before collapsing into a ring. VBX stent recoil was <2.5% on all dilations. CONCLUSIONS: LS stents had the greatest over-dilation potential. VBX stents had the least recoil but tended to foreshorten significantly 3-4 mm above nominal. Regardless of nominal size, all iCast stents (including the 5 mm) tolerated dilation to a maximum of 12-13 mm.

Apical muscular ventricular septal defect closure via hybrid approach using a right ventricular stay suture.

Transcatheter closure of large apical muscular ventricular septal defects (VSDs) can be performed via transfemoral or hybrid approach. A very large apical muscular VSD was closed via a hybrid approach. A strategy for deployment of a right ventricular stay suture was utilized to minimize the risk of device embolization without the use of bypass and without externalization of a portion of the device.

Assessing Single Ventricle Function in the Fontan Circulation using Wave Intensity Analysis.

Single ventricle hearts palliated with the Fontan operation present complications later in life as a result of increased venous pressures and abnormal ventricle function. Wave intensity analysis uses measurements of blood velocity and pressure to represent arterial hemodynamics as summations of energy waves. This methodology could potentially be a useful tool in assessment of Fontan patients. The clinical value of wave intensity parameters was utilized to evaluate the functional performance of the single ventricle in Fontan patients. A retrospective analysis of invasive hemodynamic data was retrospectively obtained from routine cardiac catheterization of patients with Fontan circulation (n = 20) and comparison to those with biventricular circulation (n = 10) who presented to the catheterization laboratory for closure of small patent ductus arteriosus (PDAs). Wave intensity analysis and wave energy flux was calculated using aortic pressure waveforms and echocardiography aortic Doppler measurements as previously described. Significant differences were seen in the peak forward compression wave (p = 0.013), early systolic energy flux (p = 0.005) and the systolic and diastolic ratio (p = 0.006) in Fontan patients versus controls. Within the Fontan group, there was a positive correlation (0.54, p = 0.02) between the wave speed and pulmonary vascular resistance. Early systolic energy flux was a potential individual indicator of a Fontan patients heart failure classification (AUC = 0.71). Wave intensity analysis could be a useful tool in screening Fontan patients and predicting clinical outcomes and Fontan failure. Future prospective analyses of Fontan hemodynamics and WIA are needed.

The Potential Impact and Timeline of Engineering on Congenital Interventions.

Congenital interventional cardiology has seen rapid growth in recent decades due to the expansion of available medical devices. Percutaneous interventions have become standard of care for many common congenital conditions. Unfortunately, patients with congenital heart disease often require multiple interventions throughout their lifespan. The availability of transcatheter devices that are biodegradable, biocompatible, durable, scalable, and can be delivered in the smallest sized patients will rely on continued advances in engineering. The development pipeline for these devices will require contributions of many individuals in academia and industry including experts in material science and tissue engineering. Advances in tissue engineering, bioresorbable technology, and even new nanotechnologies and nitinol fabrication techniques which may have an impact on the field of transcatheter congenital device in the next decade are summarized in this review. This review highlights recent advances in the engineering of transcatheter-based therapies and discusses future opportunities for engineering of transcatheter devices.

Trans-apical systemic tricuspid valve-in-ring replacement.

Transcatheter valve replacement offers a safe and effective alternative to traditional surgical techniques in patients with congenital heart disease, especially those at high surgical risk. The most common causes of morbidity and mortality in patients with D-transposition of the great arteries status post Senning or Mustard repair is severe tricuspid valve (TV) regurgitation. Replacement of the systemic TV may be useful in those without severe systemic ventricular dysfunction. We present a case of a patient with D-loop transposition of the great arteries status post Mustard repair and TV ring placement with subsequent severe systemic TV regurgitation, at high surgical risk, who underwent a transcatheter valve replacement via a trans-apical approach using an Edwards Sapien XT valve.

Risk factors for infective endocarditis following transcatheter pulmonary valve replacement in patients with congenital heart disease.

OBJECTIVES: We sought to delineate the risk factors for infective endocarditis (IE) in patients undergoing transcatheter pulmonary valve replacement (TCPVR). BACKGROUND: Despite the therapeutic benefits of TCPVR for treatment of dysfunctional right ventricular outflow tracts, IE is a major complication of the approach. Specific hemodynamic gradients and patient immune status as predisposing factors for IE are largely unexplored. METHODS: We performed a retrospective review of patients who had undergone TCPVR at UCLA between October 2010 and October 2017. Cases of IE were diagnosed based on the modified Duke criteria. RESULTS: Two hundred and thirty-five cases of TCPVR were performed with a mean follow-up of 2.6 years (range 0.0-8.0 years). Sixteen distinct IE events developed in 13 patients (Melody™ n = 12, SAPIEN n = 1), with a median time from implant to IE of 3.3 years (range 2.0-7.2 years). Univariate Cox regression showed that immunocompromised status was significantly associated with the development of IE hazard ratios (HR 5.43 [1.80-16.4], p = .003). Kaplan-Meier curves show that the 5-year freedom from IE among immunocompetent patients was 87% (95% CI 78-96%) versus 64% (95% CI 39-89%) among immunocompromised patients (log-rank p = .02). Postimplant right ventricular systolic pressure was higher among immunocompromised patients (p = .03). The risk of IE post-TCPVR in immunocompromised patients with residual pulmonary stenosis was 43%. CONCLUSIONS: Among the risk factors examined in this study, immunocompromised status was the most significant predictor of IE development post-TCPVR. Patients with the lowest risk of IE are those with competent immune systems, without a history of IE, and with minimal residual pulmonary valve gradients post-TCPVR.

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.

Results of the combined U.S. multicenter postapproval study of the Nit-Occlud PDA device for percutaneous closure of patent ductus arteriosus.

OBJECTIVES: To report the results of the Nit-Occlud PDA prospective postapproval study (PAS) along with a comparison to the results of the pivotal and continued access trials. BACKGROUND: The Nit-Occlud PDA (PFM Medical, Cologne, Germany), a nitinol coil patent ductus arteriosus (PDA) occluder, was approved by the Food and Drug Administration in 2013. METHODS: The PAS enrolled a total of 184 subjects greater than 6 months of age, weighing at least 5 kg, with PDAs less than 4 mm by angiography at 11 centers. Patients were followed prospectively at 2 months, 12 months, and 24 months postprocedure. These outcomes were compared to the 357 subjects enrolled in the pivotal and continued access protocols. Efficacy and safety data were reported. RESULTS: Among 184 subjects enrolled for the PAS between 2014 and 2017, 180 (97.8%) had successful device implantation. After 12 months, 98.7% (150/152) had trivial or no residual shunt by echocardiography and two subjects had only small residual shunts. There were three device embolizations that were all retrieved by snare without clinical consequence. Together with the pivotal and continued access study, 97.4% (449/461) had complete echocardiographic closure at 12 months in 541 enrolled subjects. The composite success was 94.4%. There were no mortalities and no serious device-related adverse events. CONCLUSIONS: The Nit-Occlud PDA is a safe and effective device for closure of a small to moderate sized PDA. There were no serious device-related adverse events in a large cohort of three clinical trials.

Incidence and outcome of infective endocarditis following percutaneous versus surgical pulmonary valve replacement.

OBJECTIVES: To provide a comparison of the outcome of infective endocarditis (IE) in patients undergoing transcatheter pulmonary valve replacement (TPVR) versus surgical pulmonary valve replacement (SPVR). BACKGROUND: Although TPVR is thought to be associated with a higher risk of IE than SPVR, there is paucity of data to support this. METHODS: Patients who underwent TPVR or SPVR at UCLA between October 2010 and September 2016 were included and retrospectively analyzed. RESULTS: Three hundred forty-two patients underwent PVR at UCLA including 134 SPVR and 208 TPVR. Patients undergoing TPVR were more likely to have had a history of endocarditis than those undergoing SPVR (5.3% vs. 0.7%, P = 0.03) and a right ventricle to pulmonary artery (RV to PA) conduit (37% vs. 17%, P = 0.0001). Two SPVR and seven TPVR patients developed IE with a 4-year freedom from endocarditis of 94.0% in the SPVR versus 84% in the TPVR group (P = 0.13). In patients who underwent TPVR and developed endocarditis, the mean gradient across the RVOT prior to intervention was higher (28.1 ± 4.5 vs. 17.4 ± 0.6 mmHg, P = 0.02) and were more likely to have a conduit (71% vs. 36%, P = 0.049). CONCLUSIONS: In this study, patients undergoing TPVR were not at a higher risk of IE than patients undergoing SPVR. TPVR patients were more likely to have had a prior history of IE and RV-PA conduit. The patients at highest risk were those with stenotic RV to PA conduits who were treated with TPVR.

4D MUSIC CMR: value-based imaging of neonates and infants with congenital heart disease.

BACKGROUND: 4D Multiphase Steady State Imaging with Contrast (MUSIC) acquires high-resolution volumetric images of the beating heart during uninterrupted ventilation. We aim to evaluate the diagnostic performance and clinical impact of 4D MUSIC in a cohort of neonates and infants with congenital heart disease (CHD). METHODS: Forty consecutive neonates and infants with CHD (age range 2 days to 2 years, weight 1 to 13 kg) underwent 3.0 T CMR with ferumoxytol enhancement (FE) at a single institution. Independently, two readers graded the diagnostic image quality of intra-cardiac structures and related vascular segments on FE-MUSIC and breath held FE-CMRA images using a four-point scale. Correlation of the CMR findings with surgery and other imaging modalities was performed in all patients. Clinical impact was evaluated in consensus with referring surgeons and cardiologists. One point was given for each of five key outcome measures: 1) change in overall management, 2) change in surgical approach, 3) reduction in the need for diagnostic catheterization, 4) improved assessment of risk-to-benefit for planned intervention and discussion with parents, 5) accurate pre-procedural roadmap. RESULTS: All FE-CMR studies were completed successfully, safely and without adverse events. On a four-point scale, the average FE-MUSIC image quality scores were >3.5 for intra-cardiac structures and >3.0 for coronary arteries. Intra-cardiac morphology and vascular anatomy were well visualized with good interobserver agreement (r = 0.46). Correspondence between the findings on MUSIC, surgery, correlative imaging and autopsy was excellent. The average clinical impact score was 4.2 ± 0.9. In five patients with discordant findings on echo/MUSIC (n = 5) and catheter angiography/MUSIC (n = 1), findings on FE-MUSIC were shown to be accurate at autopsy (n = 1) and surgery (n = 4). The decision to undertake biventricular vs univentricular repair was amended in 2 patients based on FE-MUSIC findings. Plans for surgical approaches which would have involved circulatory arrest were amended in two of 28 surgical cases. In all 28 cases requiring procedural intervention, FE-MUSIC provided accurate dynamic 3D roadmaps and more confident risk-to-benefit assessments for proposed interventions. CONCLUSIONS: FE-MUSIC CMR has high clinical impact by providing accurate, high quality, simple and safe dynamic 3D imaging of cardiac and vascular anatomy in neonates and infants with CHD. The findings influenced patient management in a positive manner.

Transcatheter native pulmonary valve and tricuspid valve replacement with the sapien XT: Initial experience and development of a new delivery platform.

BACKGROUND: While the Melody valve is unable to be used for replacement of large pulmonary outflow tracts, the 29 mm Sapien XT transcatheter valve, designed specifically for aortic valve replacement, can potentially be used in these large native outflow tracts. Techniques to enable off-label use of the Sapien XT valve for large-diameter pulmonary and tricuspid valve replacement are described. METHODS: Use of the Sapien valve for transcatheter pulmonary and tricuspid valve replacement using both the commercially available Novaflex+ system and using a novel flexible delivery system was reviewed. This customized flexible delivery platform was constructed using the Ensemble sheath and a 30 mm Nucleus balloon. This system was bench tested prior to its clinical use. RESULTS: Ten patients had successful implantation of Sapien valves into native right ventricular outflow tracts (RVOTs) (n = 7) or tricuspid valves (n = 3). There was no stenosis or regurgitation after Sapien valve implantation. Several of the pulmonary valve replacement cases were extremely challenging due to the limited flexibility of the Novaflex system. The Sapien valve was crimped onto a 30 mm Nucleus balloon preloaded through an Ensemble sheath. This system was able to consistently deliver the Sapien valve safely in a bench model as well as in native RVOTs in two patients. CONCLUSION: The 29 mm Sapien XT valve allows for large-diameter transcatheter valve replacement in both the pulmonary and tricuspid positions. Initial results of new techniques to utilize a more flexible delivery platform are described that could obviate the need for the Novaflex system. © 2016 Wiley Periodicals, Inc.

Transcatheter closure of an iatrogenic ventricular septal defect after SAPIEN valve implantation.

A 57-year-old woman developed progressive calcific mitral and aortic valve disease with a porcelain aorta secondary to a history of radiation therapy. She was considered a very poor operative candidate and referred for transcatheter aortic valve replacement (TAVR). Four weeks after extensive coronary artery stenting, a TAVR was performed with a 23 mm Edwards SAPIEN valve (Edwards Life Sciences, Irvine, CA) through a transapical approach. Post-operatively, her symptoms of dyspnea persisted and worsened. She was found to have an acquired ventricular septal defect (VSD) measuring 8 mm by 5 mm by transesophageal echocardiogram and by a CT angiogram. Percutaneous VSD closure was accomplished with an 8 mm Muscular VSD Occluder (St. Jude Medical, St. Paul, MN) with elimination of her shunt, improvement of her dyspnea, and marked improvement in exercise tolerance.

Transcatheter melody valve placement in large diameter bioprostheses and conduits: What is the optimal "Landing zone"?

OBJECTIVES: This study sought to elucidate the optimal bioprosthetic valve (BPV) size prior to Melody valve implantation. BACKGROUND: BPVs provide an ideal "landing zone" for future Melody valve insertion. To guide surgical choice of BPV size, it is important to understand which BPV size can serve consistently as substrates for Melody valve placements. METHODS: A database of all patients who underwent Melody implantation at UCLA or Kaiser Permanente Los Angeles from 2010 to 2014 was analyzed retrospectively. Patients with an existing BPV were stratified into those with a valve diameter of ≥27 mm or <27 mm. RESULTS: One hundred and sixty patients underwent catheterization with the intention to implant a Melody valve. Melody valve implantation was performed in the pulmonary position in 52 patients with prior BPVs. The immediate procedural success rate was 100%. Immediately post-Melody, the right ventricular to pulmonary artery gradient was significantly higher in the <27 mm group compared to the ≥27 mm group (14.3±3 vs. 8.6±6.8, P=0.006). There was a significantly shorter time from prior valve replacement to Melody implantation in the <27 mm group. There was one patient in whom transcatheter pulmonary valve implantation was aborted due to inadequate landing zone in the <27 mm group, and no patients in the ≥27 mm group (P=NS). CONCLUSIONS: The results of this study indicate that 27 and 29 mm BPV provide a superior landing zone for Melody valve implantation with excellent immediate and intermediate term hemodynamic results when compared to smaller BPVs less than 27 mm.

SCAI expert consensus statement for advanced training programs in pediatric and congenital interventional cardiac catheterization.

Pediatric and Congenital Interventional Cardiology is the practice of catheter-based techniques that improve cardiac physiology and circulation through the treatment of heart disease in children and adults with congenital or acquired heart defects. Over the last decade, and since last published training guidelines for pediatric cardiac catheterization and interventional cardiology were published in 2005 [1] the field of Pediatric and Congenital Cardiac Catheterization has evolved into a predominantly interventional discipline. As there is no sub-specialty certification for interventional cardiac catheterization in pediatrics, the Congenital Heart Disease Committee of the Society of Cardiovascular Angiography and Interventions has put together this consensus statement for advanced training in pediatric and congenital interventional cardiac catheterization. The statement puts forth recommendations for program infrastructure in terms of teaching, personnel, equipment, facilities, conferences, patient volume and trainee assessment. This is meant to set a standard for training programs as well as giving applicants a basis on which to judge and compare programs.

In vitro evaluation of an external compression device for fontan mechanical assistance.

While Fontan palliation in the form of the total cavopulmonary connection has improved the management of congenital single ventricle physiology, long-term outcomes for patients with this disease are suboptimal due to the lack of two functional ventricles. Researchers have shown that ventricular assist devices (VADs) can normalize Fontan hemodynamics. To minimize blood contacting surfaces of the VAD, we evaluated the use of an external compression device (C-Pulse Heart Assist System, Sunshine Heart Inc.) as a Fontan assist device. A mock circulation was developed to mimic the hemodynamics of a hypertensive Fontan circulation in a pediatric patient. The Sunshine C-Pulse compression cuff was coupled with polymeric valves and a compressible tube to provide nonblood-contacting pulsatile flow through the Fontan circulation. The effect of the number, one or two, and placement of valves, before or after the compression cuff, on inferior vena cava pressure (IVCP) was studied. In addition, the effect of device inflation volume and compression rate on maintaining low IVCP was investigated. With one valve located before the cuff, the device was unable to maintain an IVCP below 15.5 mm Hg. With two valves, the C-Pulse was able to maintain IVCP as low as 8.5 mm Hg. The C-Pulse provided pulsatile flow and pressure through the pulmonary branch of the mock circulation with a pulse pressure of 16 mm Hg and 180 mL/min additional flow above unassisted flow. C-Pulse compression reduced IVCP below 12 mm Hg with 13 cc inflation volume and compression rates above 105 bpm. This application of an external compression device combined with two valves has potential for use as an artificial right ventricle by maintaining low IVCP and providing pulsatile flow through the lungs.