Aspirin Responsiveness in a Cohort of Pediatric Patients with Right Ventricle to Pulmonary Artery Conduits and Transcatheter Valve Replacement Systems.

The aim of this study was to determine the rate of aspirin responsiveness in a cohort of pediatric patients with in situ xenograft valved right ventricle to pulmonary artery (RV-PA) conduits and/or transcatheter valve replacements (TVR). Aspirin is routinely prescribed to these patients. Optimizing anti-platelet therapy could promote valve longevity and reduce the risk of infective endocarditis in this at-risk group. This was a prospective, observational study. Patients were recruited from both ward and outpatient settings. Patients were eligible if under 18 years and taking aspirin. Non-response to aspirin was defined as > 20% platelet aggregation using light transmission platelet aggregometry (LTA) and < 50% platelet inhibition by thromboelastography with platelet mapping (TEGPM). Participants were invited to provide a confirmatory sample in cases of aspirin resistance and dose adjustments were made. Thirty patients participated. Median age was 9 years (2 months to 18 years). The majority (93%) had complex right ventricular outflow tract pathology. 13 (43%) had an RV-PA conduit and 24 (80%) had a TVR, with valve situated in conduit in 7 (23%) cases. Rate of aspirin non-response on initial testing was 23% (n = 7/30) with median LTA 74.55% (60-76%) and TEG 13.25% (0-44%) in non-responders. Non-responders were more likely to be under 1 year. Two patients required dose increases and one patient non-adherence to dose was identified. Four patients on repeat testing were responsive to aspirin by laboratory tests. The rate of aspirin non-response on laboratory testing in this cohort of patients was 23% and resulted in therapeutic intervention in 10%.

Isolated left ventricular apical hypoplasia: Systematic review and analysis of the 37 cases reported so far.

BACKGROUND: Isolated left ventricular apical hypoplasia (ILVAH), also known as truncated left ventricle (LV), is a very unusual cardiomyopathy. It is characterised by a truncated, spherical, and non-apex forming LV. The true apex is occupied by the right ventricle. Due to the rarity of the disease, just a few case reports and limited case series have been published in the field. AIM: To analysing the so far 37 reported ILVAH cases worldwide. METHODS: The electronic databases PubMed and Scopus were investigated from their establishment up to December 13, 2022. RESULTS: The majority of cases reported occurred in males (52.7%). Mean age at diagnosis was 26.1 ± 19.6 years. More than a third of the patients were asymptomatic (35.1%). The most usual clinical presentation was breathlessness (40.5%). The most commonly detected electrocardiogram changes were T wave abnormalities (29.7%) and right axis deviation with poor R wave progression (24.3%). Atrial fibrillation/flutter was detected in 24.3%. Echocardiography was performed in 97.3% of cases and cardiac MRI in 91.9% of cases. Ejection fraction was reduced in more than a half of patients (56.7%). An associated congenital heart disease was found in 16.2%. Heart failure therapy was administered in 35.1% of patients. The outcome was favorable in the vast majority of patients, with just one death. CONCLUSION: ILVAH is a multifaceted entity with a so far unpredictable course, ranging from benign until the elderly to sudden death during adolescence.

Picking the Locked Door: Experiences and Techniques in Transseptal Puncture Post-Atrial Septal Defect Occlusion.

The management of atrial septal defects (ASDs) has been revolutionized by the advent of percutaneous transvenous occlusion devices. This case series describes techniques required to perform a transeptal puncture safely and effectively in patients postimplantation of an atrial septal defect occluder to facilitate catheter ablation of atrial arrhythmias. (Level of Difficulty: Intermediate.).

Transfemoral Perimembranous Ventricular Septal Defect Device Closure in Infants Weighing ≤ 10 kg.

Transcatheter closure of Perimembranous VSDs (PMVSD) remains challenging particularly in infants. The aim of this study is to evaluate the efficacy and safety of transfemoral PMVSD device closure in infants weighing ≤ 10 kg in a single centre. Retrospective review of departmental databases and medical charts to define patient cohort and collect demographic, procedural and follow-up data. Between July 2014 and March 2021, 16 patients underwent attempted transfemoral PMVSD device closure (12 retrograde) at a median age of 11 months (interquartile range [IQR] 9-15.5) and a median weight of 8.3 kg (IQR 7.2-9.5). All patients were either symptomatic, had progressive left heart dilation or had VSD associated valve regurgitation. Median defect size on pre-procedural transoesophageal echocardiography was 6.8 mm (IQR 6-8.5). Median device waist size was 6 mm (IQR 4.5-8). Successful device placement was achieved in 14 patients (88%). One patient developed moderate aortic and tricuspid valve regurgitation upon retrograde and antegrade device deployment, respectively, and subsequently underwent surgical closure. The second patient developed progressive aortic regurgitation (AR) 2 days post procedure, and also underwent surgical removal with no residual AR. There was no cases of device embolization and no femoral arterial compromise. On median follow-up of 40.5 months (IQR 25-64), none of the patients developed complete heart block. Three patients (18.75%) had small residual shunts at latest follow-up which have not required any further intervention. Device closure of PMVSD's in children weighing ≤ 10 kg is feasible and safe with good procedural success rates. Use of both the antegrade and retrograde approaches may be necessary depending on anatomical variances.

Short- and medium-term outcomes for patent ductus arteriosus stenting in neonates ≤2.5 kg with duct-dependent pulmonary circulation.

BACKGROUND: Morbidity with surgical systemic-to-pulmonary artery shunting (SPS) in infants ≤2.5 kg has remained high. Patent ductus arteriosus (PDA) stenting may be a valid alternative. The objective of this study is to evaluate outcomes following PDA stenting in patients ≤2.5 kg from four large tertiary centers. METHODS: Retrospective review of all neonates ≤2.5 kg with duct-dependent pulmonary circulation who underwent PDA stenting. Procedural details, pulmonary arterial growth, reinterventions, surgery type, and outcomes were assessed. RESULTS: PDA stents were implanted in 37 of 38 patients attempted (18 female) at a median procedural weight of 2.2 kg (interquartile range [IQR], 2-2.4 kg). Seven patients (18%) had a genetic abnormality and 16 (42%) had associated comorbidities. The median intensive care unit stay was 4 days (IQR, 2-6.75 days), and the median hospital stay was 20 days (IQR, 16-57.25). One patient required a rescue shunt procedure, with three others requiring early SPS (<30 days postprocedure). Twenty patients (54%) required reintervention with either balloon angioplasty, restenting, or both. At 6-month follow-up, right pulmonary artery growth (median z-score -1.16 to 0.01, p = 0.05) was greater than the left pulmonary artery (median z-score -0.9 to -0.64, p = 0.35). Serious adverse effects (SAEs) were seen in 18% (N = 7) of our cohort. One patient developed an SAE during planned reintervention There were no intraprocedural deaths, with one early procedure-related mortality, and three interstage mortalities not directly related to PDA stenting. CONCLUSIONS: PDA stenting in infants ≤2.5 kg is feasible and effective, promoting pulmonary artery growth. Reintervention rates are relatively high, though many are planned to allow for optimal growth before a definitive operation.

Use of the Medtronic Microvascular Plug 7Q for transcatheter closure of large patent ductus arteriosus in infants weighing less than 2.5 kg.

BACKGROUND: The sole Food and Drug Administration-approved device for transcatheter closure of the patent arterial duct in premature infants is indicated for patent ductus arteriosus (PDAs) ≤ 4 mm in diameter. We report a two-center experience with transcatheter closure of large PDAs (>4 mm) in infants weighing <2.5 kg using the Microvascular Plug 7Q (MVP-7Q) device. METHODS: This is a retrospective review of departmental databases and medical charts to define patient cohort and report demographic, procedural, and follow-up data. RESULTS: Twenty-two patients (12 male) with a median gestational age and birthweight of 25.5 weeks (interquartile range [IQR] = 24-28) and 800 g (572-1075), respectively, underwent attempted PDA occlusion with the MVP-7Q using a transvenous approach. The median age and weight at the time of PDA occlusion was 32 days (IQR = 24-28) and 1100 g (IQR = 960-1700), respectively. The median PDA length was 12 mm (IQR = 11-12.65). The median PDA diameters at the aortic and pulmonary ends were 5.1 (IQR = 4.9-5.5) and 4.8 mm (IQR = 4.6-5.3), respectively. Successful device occlusion was achieved in 20 patients (91%). There were two failed attempts: One due to inappropriate sizing, and the other secondary to left pulmonary artery stenosis. There were no procedural complications and no residual shunting on follow-up. CONCLUSIONS: The MVP-7Q is safe and effective for transcatheter closure of large (>4 mm) PDAs in infants <2.5 kg. The lack of retention disks may help with avoiding impingement on surrounding vessels.

A case report of ventricular septal defect complicating transcatheter aortic valve implant for aortic regurgitation: novel complication and technical considerations.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has proven efficacy in the treatment of aortic stenosis (AS). Understandably, there is increasing enthusiasm for its use to treat aortic regurgitation (AR). However, there are significant anatomical differences between AS and AR which make TAVI for AR more complex. CASE SUMMARY: We present the case of technically challenging TAVI for severe AR, which was complicated by a traumatic ventricular septal defect (VSD) that required percutaneous closure. To our knowledge, this is the first published case of VSD post-TAVI for AR. DISCUSSION: This unanticipated complication highlights anatomical differences between TAVI use in AS and AR. Lack of aortic valve calcification and excessive annular compliance made stable deployment of a self-expanding valve extremely challenging. Despite device oversizing, repeated embolization of the prosthesis into the left ventricular outflow tract traumatized the interventricular septum.

Paraganglioma in an adolescent awaiting a cardiac transplant due to unrepaired congenital cyanotic heart disease and a univentricular heart: the first reported case.

We report a case of a 16-year-old adolescent male born with univentricular congenital cyanotic heart disease (CCHD) who was diagnosed with an incidental paraganglioma while awaiting a cardiac transplant. The coexistence of paraganglioma and univentricular CCHD is very rare, with no previous cases described in the literature of a patient concurrently requiring a cardiac transplant. The complex physiology associated with a common atrium, common ventricle, aortopulmonary lung perfusion and a hypoplastic left lung rendered our patient extremely vulnerable to catecholamine-mediated effects of preload, contractility and afterload. The interactions and interdependence between these systems provided unique difficulties for perioperative management with serious implications for prospective cardiac transplant.

Right ventricular outflow tract stenting in symptomatic infants without the use of a long delivery sheath.

BACKGROUND AND OBJECTIVES: Right ventricular outflow tract (RVOT) stenting improves systemic oxygenation and facilitates pulmonary arterial growth in symptomatic infants prior to repair of tetralogy of Fallot. The aim of this study was to evaluate the safety and efficacy of RVOT stenting without the use of a long delivery sheath. METHODS: Retrospective data analysis of patients under 1 year of age undergoing RVOT stenting from January 2010 to January 2020 at a single tertiary pediatric cardiology center. RESULTS: Sixty-three RVOT stents were deployed during 53 procedures into 44 patients. The median age and weight at insertion were 41 days (range 2-204) and 3.6 kg (range 1.59-7) respectively. Thirty-one procedures were semi-elective and 22 were emergencies. Stent positioning was guided by transthoracic echocardiogram and/or RV angiography from a pigtail micro-catheter placed via the aorta. The median total procedure and fluoroscopy times were 67.5 (range 15-145) and 19 min (1-107), respectively. The median length of hospital stay was 7 days (range 1-258). Twenty-one patients were admitted to ICU post-procedure with a median ICU length of stay of 3 days (range 3-11). There were three major complications including two deaths within 30 days of the procedure. A patient with Cornelia de Lange Syndrome (1.8 kg) died following stent migration and inability to wean from emergency cardiopulmonary bypass and the second infant had an unexplained asystolic arrest post-procedure while awaiting transfer to ICU. CONCLUSIONS: RVOT stenting is technically possible with minimal complications without the need for a long delivery sheath. Additional imaging with transthoracic echocardiography can facilitate the safe deployment of the stent.

Case series of late lead dislodgement of Medtronic SelectSecure 3830 pacing leads in growing paediatric patients.

BACKGROUND: The SelectSecure lumenless 3830 pacing lead is often considered to be the pacing lead of choice for transvenous pacing in children because of its small diameter, lead strength, and reliable long-term sensing and pacing characteristics. One of the potential long-term pitfalls of a sturdy pacing lead is relative retraction with growth in children resulting in late lead dislodgement. CASE SUMMARY: We report two cases of late SelectSecure 3830 lead dislodgement at 11.8 years (Case 1) and 8.8 years (Case 2), respectively, post the initial implantation. Case 1 was diagnosed with congenital complete heart block (CHB) at 9 months old when he presented with unconfirmed diphtheria infection. Case 2 was diagnosed with CHB at 14 weeks of age with positive maternal anti-Ro antibodies. Both patients underwent implantation of a transvenous permanent pacemaker implantation with Medtronic SelectSecure 3830 lead due to symptomatic bradycardia. Apart from a pulse generator change at 8.5 years (Case 1) and 7 years (Case 2), respectively, post-implant due to normal battery depletion, both patients are well in the interim. DISCUSSION: As part of the pacemaker follow-up for rapidly growing children, we recommend more frequent surveillance of lead 'tautness' by chest radiography especially in children with CHB with no underlying heart rhythm.

Percutaneous transcatheter occlusion of left atrioventricular valve in a patient with single ventricle and severe atrioventricular valve regurgitation.

Many patients with single ventricle physiology suffer from atrioventricular valve (AVV) regurgitation which may worsen their cardiac function and cause symptoms. It has been postulated that elimination of the nondominant hypoplastic AVV regurgitation, might improve the clinical status in patients post-Fontan surgery. We describe a case of hypoplastic left heart variant, post Fontan surgery who had severe left AVV regurgitation and underwent percutaneous transcatheter occlusion of the hypoplastic left AVV, using a VSD occluder device. At 3 months post procedure, the patient is improved. Transcatheter closure of a regurgitant hypoplastic AVV in a patient with single ventricle helps to improve the patient's cardiac function and clinical status.

Hybrid Subxiphoid Perventricular Approach as an Alternative Access in Neonates and Small Children Undergoing Complex Congenital Heart Interventions.

The hybrid subxiphoid perventricular approach provides direct access through the heart and may alleviate the technical limitations of complex percutaneous interventions particularly in infants with low body weight. We present the outcomes from a tertiary cardiology center using this approach. We performed a retrospective review of all patients less than 15 kg who underwent a hybrid perventricular approach via a small subxiphoid incision. Medical records were reviewed to obtain clinical, demographic and outcome data. Seventeen patients underwent 18 hybrid perventricular procedures using a subxiphoid approach. Median age at time of procedure was 4.6 months (IQR = 1.6 to 18 months) and median weight was 6.2 kgs (IQR = 3.4 to 8.6 kgs). Six patients underwent hybrid pulmonary valve replacement (PVR), 5 patients underwent pulmonary outflow stenting, and 5 infants underwent hybrid ventricular septal defect (VSD) device closure. One patient with a single ventricle who did not tolerate a percutaneous approach underwent left pulmonary artery (LPA) stenting for severe LPA coarctation with subsequent right ventricular outflow tract (RVOT) stenting. One further patient underwent implantation of a larger diameter stent for pulmonary artery bifurcation stenosis. Procedure success rate was 89% with two of the VSD cases reverted to open surgical repair. There were no intra-procedural complications; however, one patient died within 72 h. Minor adverse events occurred in 2 patients including a wound infection in one patient with an immunodeficiency syndrome. Hybrid subxiphoid perventricular approach provides an excellent alternative access to the heart especially in low birth weight infants to prevent hemodynamic instability or in small children requiring large delivery sheaths.

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.

Short to medium term outcomes of right ventricular outflow tract stenting as initial palliation for symptomatic infants with complete atrioventricular septal defect with associated tetralogy of Fallot.

OBJECTIVES: To assess the impact of right ventricular outflow tract (RVOT) stenting as the primary palliation in infants with complete atrioventricular septal defect with associated tetralogy of Fallot (cAVSD/TOF). BACKGROUND: Historically, palliation of symptomatic patients with cAVSD/TOF has been achieved through surgical systemic to pulmonary artery shunting. More recently RVOT stenting has evolved as an acceptable alternative in patients with tetralogy of Fallot. METHODS: Retrospective review of all patients with cAVSD/TOF who underwent RVOT stenting as palliation over a 13-year period from two large tertiary referral centers. RESULTS: Twenty-six patients underwent RVOT stenting at a median age of 57 days (interquartile range [IQR] 25.5-106.5). Median weight for stent deployment was 3.7 kg (IQR 2.91-5.5 kg). RVOT stenting improved oxygen saturations from a median of 72% (IQR 70-76%) to 90% (IQR 84-92%), p < .001. There was a significant increase in the median Z-score for both branch pulmonary arteries at median follow-up of 255 days (IQR 60-455). Eight patients required RVOT stent balloon dilatations and 8 patients required re-stenting for progressive desaturation. The median duration between reinterventions was 122 days (IQR 53-294 days). Four patients died during the follow-up period. No deaths resulted from the initial intervention. To date, definitive surgical intervention was achieved in 19 patients (biventricular repair n = 15) at a median age of 369 days (IQR 223-546 days). CONCLUSION: RVOT stenting in cAVSD/TOF is a safe and effective palliative procedure in symptomatic infants, promoting pulmonary artery growth and improving oxygen saturations.

Decision-Making in the Catheter Laboratory: The Most Important Variable in Successful Outcomes.

Increasingly the importance of how and why we make decisions in the medical arena has been questioned. Traditionally the aeronautical and business worlds have shed a light on this complex area of human decision-making. In this review we reflect on what we already know about the complexity of decision-making in addition to directing particular focus on the challenges to decision-making in the high-intensity environment of the pediatric cardiac catheterization laboratory. We propose that the most critical factor in outcomes for children in the catheterization lab may not be technical failures but rather human factors and the lack of preparation and robust shared decision-making process between the catheterization team. Key technical factors involved in the decision-making process include understanding the anatomy, the indications and objective to be achieved, equipment availability, procedural flow, having a back-up plan and post-procedural care plan. Increased awareness, pre-catheterization planning, use of standardized clinical assessment and management plans and artificial intelligence may provide solutions to pitfalls in decision-making. Further research and efforts should be directed towards studying the impact of human factors in the cardiac catheterization laboratory as well as the broader medical environment.

The Assessment of Cardiac Masses by Cardiac CT and CMR Including Pre-op 3D Reconstruction and Planning.

PURPOSE OF REVIEW: The purpose of this review is to (1) review the recent evidence examining the use of CT and CMR in the assessment of a suspected cardiac mass, (2) summarize the typical imaging features of the most common cardiac masses, and (3) examine the latest developments in the use of three-dimensional reconstructions and models in the preoperative assessment of a cardiac mass. RECENT FINDINGS: CMR can distinguish between tumors and non-tumor masses and between benign and malignant mass with a high degree of accuracy. CT and CMR are complementary tools in the evaluation of cardiac masses. CMR is the preferred initial imaging modality due to its versatile imaging planes and superior tissue characterization. CT better depicts calcification and has a higher spatial resolution compared with CMR, which is of particular importance in preoperative planning. CT also offers a valuable alternative in those with contraindications to CMR. Three-dimensional reconstructions, particularly of CT datasets, are a valuable adjunct in the preoperative assessment of a cardiac mass and may allow a better appreciation of the margins of the mass and its relationship with surrounding structures. Three-dimensional printing is an emerging technology which may be of additional value in selected patients with a cardiac mass.

Experience of stent implantation for recurrent aortic arch obstruction following Norwood or Damus-Kaye-Stansel operation over the last decade.

BACKGROUND: Recurrent aortic arch obstruction following the Norwood procedure is recognised as an important complication. Balloon arch angioplasty is associated with a high recoarctation rate. METHODS: We sought to evaluate the prevalence and outcome of stent implantation for recoarctation in children following Norwood or Damus-Kaye-Stansel procedure over the past decade at a single national cardiology centre. RESULTS: Of 114 children who underwent Norwood procedure or Damus-Kaye-Stansel procedure between January 2003 and June 2013, 80 patients survived. Of these 15 children underwent stent implantation for recoarctation. Six of these patients had previous balloon angioplasty. The median age at stent implantation was 4.4 months (range 2-82 months). The median peak aortic arch gradient at catheterisation decreased from 26mmHg (range 10-70mmHg) to 2mmHg (range 0-20mmHg). The median luminal diameter increased from 4.7 mm (range 3.2-7.9 mm) to 8.6 mm (range 6.2-10.9 mm). The median coarctation index increased by 0.49 (range = 0.24-0.64). A Valeo stent was employed in 11 children, a Palmaz Genesis stent in 2 patients, a MultiLink stent in 1 child, and a Jomed covered stent in 1 child. Two factors were associated with the need for stent placement: previous arch angioplasty (p valve < 0.001, χ-square 11.5) and borderline left ventricle (p = 0.04, χ-square = 4.1). Stent migration occurred in one child. There were two deaths related to poor right ventricular systolic function and severe tricuspid regurgitation. Six patients underwent redilation of the stent with no complications. CONCLUSIONS: The prevalence of recurrent aortic arch obstruction following Norwood/Damus-Kaye-Stansel procedure was 18%. Stent implantation is safe and reliably eliminates the aortic obstruction. Redilation can be successfully achieved to accommodate somatic growth or development of stent recoarctation.

Atrioventricular septal defect and tetralogy of Fallot - A single tertiary center experience: A retrospective review.

BACKGROUND: Complete atrioventricular septal defect (CAVSD) in association with tetralogy of Fallot is a rare and complex disease that makes its repair more difficult than repair of either lesion alone. We reviewed retrospectively our experience in managing this lesion. PATIENTS AND METHODS: Between February 2006 and May 2017, 16 patients who underwent repair of CAVSD/tetralogy of Fallot (TOF) were reviewed retrospectively. Fifteen patients had trisomy 21. Five patients underwent primary repair while eleven patients went for staged repair in the form of right ventricular outflow tract (RVOT) stenting (n = 9) or systemic to pulmonary (S-P) surgical shunt (n = 2). RVOT stenting has replaced surgical shunt since 2012 in our center. Early presentation with cyanosis was the main determinant factor for staged versus primary repair. RESULTS: The median age at first palliation was 46 days (range 15-99 days). The median age at total repair for both groups was 6 months (range 3-18 months); the median age for the palliated patients was 6.5 months (range 5-18 months) while the median age for primary repaired patients was 5 months (range 3-11 months). The median weight at final repair was 6.9 kg (3.7-8.2 kg). The pulmonary valve was preserved in five patients (31%), four of them had no prior palliation. Chylothorax occurred in 50% of the patients. One late mortality occurred after final repair due to sepsis. CONCLUSION: CAVSD/TOF can be repaired with low mortality and morbidity. The use of RVOT stent has replaced the surgical (S-P) shunt with acceptable results in our center.