Stage 1 and 2 Palliation: Comparing Ductal Stenting and Aorto-Pulmonary Shunts in Single Ventricles with Duct-Dependent Pulmonary Blood Flow.

Patent ductus arteriosus stenting (PDAS) for ductal-dependent pulmonary blood flow (DDPBF) provides a new paradigm for managing neonates with single ventricles (SV). Currently, sparse data exist regarding outcomes for subsequent palliation. We describe our experience with inter-stage care and stage 2 (S2P) conversion with PDAS in comparison to a prior era of patients who received surgical aorto-pulmonary shunts (APS). Retrospective review of 18 consecutive DDPBF SV patients treated with PDAS between 2016 and 2021 was done and compared with 9 who underwent APS from 2010 to 2016. Patient outcomes and pulmonary artery (PA) growth were analyzed. S2P was completed in all 18 with PDAS with no cardiac arrests and one post-S2P mortality. In the 9 APS patients, there was one cardiac arrest requiring ECMO and one mortality inter-stage. Off cardiopulmonary bypass strategy was utilized in 10/18 in the PDAS and 1/9 in the APS group (p = 0.005) at S2P. Shorter ventilation time, earlier PO feeding, and shorter hospital stay were noted in the PDAS group (p = 0.01, p = 0.006, p = 0.03) (S2P). Median Nakata index increase inter-stage was not significant between the PDAS and APS at 94.1 mm2/m2 versus 71.7 mm2/m2 (p = 0.94). Median change in pulmonary artery symmetry (PAS) was - 0.02 and - 0.24, respectively, which was statistically significant (p = 0.008). Neurodevelopmental outcomes were better in the PDAS group compared to the APS group (p = 0.02). PDAS provides excellent PA growth, inter-stage survival, progression along multistage single-ventricle palliation, and potentially improved neurodevelopmental outcomes. Most patients can be transitioned through 2 stages of palliation without CPB.

Surgical Mitral Valve Replacement Using a Catheter-Based MelodyTM Valve in a Landing Zone Constructed With a PTFE-Covered Expandable Cheatham-PlatinumTM Stent.

Mitral valve replacement using a Melody valve is a promising solution to the challenge of surgical mitral valve replacement in infants with a hypoplastic annulus. We report the creation of a landing zone in the mitral valve annulus using a Cheatham-Platinum (CP)-covered stent that facilitates Melody valve placement, helps prevent paravalvular leak, minimizes left ventricular outflow tract obstruction, and allows for potential future dilation of the valve.

Neonatal Myocardial Infarction: A Proposed Algorithm for Coronary Arterial Thrombus Management.

BACKGROUND: Neonatal myocardial infarction is rare and is associated with a high mortality of 40% to 50%. We report our experience with neonatal myocardial infarction, including presentation, management, outcomes, and our current patient management algorithm. METHODS: We reviewed all infants admitted with a diagnosis of coronary artery thrombosis, coronary ischemia, or myocardial infarction between January 2015 and May 2021. RESULTS: We identified 21 patients (median age, 1 [interquartile range (IQR), 0.25-9.00] day; weight, 3.2 [IQR, 2.9-3.7] kg). Presentation included respiratory distress (16), shock (3), and murmur (2). Regional wall motion abnormalities by echocardiogram were a key criterion for diagnosis and were present in all 21 with varying degrees of depressed left ventricular function (severe [8], moderate [6], mild [2], and low normal [5]). Ejection fraction ranged from 20% to 54% (median, 43% [IQR, 34%-51%]). Mitral regurgitation was present in 19 (90%), left atrial dilation in 15 (71%), and pulmonary hypertension in 18 (86%). ECG was abnormal in 19 (90%). Median troponin I was 0.18 (IQR, 0.12-0.56) ng/mL. Median BNP (B-type natriuretic peptide) was 2100 (IQR, 924-2325) pg/mL. Seventeen had documented coronary thrombosis by cardiac catheterization. Seventeen (81%) were treated with intracoronary tPA (tissue-type plasminogen activator) followed by systemic heparin, AT (antithrombin), and intravenous nitroglycerin, and 4 (19%) were treated with systemic heparin, AT, and intravenous nitroglycerin alone. Nineteen of 21 recovered. One died (also had infradiaphragmatic total anomalous pulmonary venous return). One patient required a ventricular assist device and later underwent heart transplant; this patient was diagnosed late at 5 weeks of age and did not respond to tPA. Nineteen of 21 (90%) regained normal left ventricular function (ejection fraction, 60%-74%; mean, 65% [IQR, 61%-67%]) at latest follow-up (median, 6.8 [IQR, 3.58-14.72] months). Two of 21 (10%) had residual trivial mitral regurgitation. After analysis of these results, we present our current algorithm, which developed and matured over time, to manage neonatal myocardial infarction. CONCLUSIONS: We experienced a lower mortality rate for infants with neonatal infarction than that reported in the literature. We propose a post hoc algorithm that may lead to improvement in patient outcomes following coronary artery thrombus.

Nine-Year Experience With the Arterial Switch Operation With Closed Coronary Transfer.

BACKGROUND: Coronary artery transfer is a critical step of the arterial switch operation (ASO) for transposition of the great arteries (TGA). Strategies for coronary transfer include open transfer before neoaortic anastomosis and closed transfer after neoaortic anastomosis. This study reports outcomes of ASO with closed coronary transfer at a single institution. METHODS: A retrospective analysis was performed of patients undergoing ASO for TGA from November 2006 to September 2015. Closed coronary transfer was universally employed. Patients were assigned to simple vs complex coronary anatomy groups. The primary outcome was overall survival. Secondary outcomes included reoperation-free survival, coronary reintervention, and aortic insufficiency. RESULTS: Ninety-six consecutive patients underwent ASO for TGA. Median follow-up was 5.8 years. Thirty-five (36%) patients had complex coronary anatomy, which was associated with significantly longer cardiopulmonary bypass and aortic cross-clamp time. Overall survival was 97.4%, and reoperation-free survival was 83.6%. There was no difference in survival or reoperation-free survival of patients with simple vs complex coronary anatomy. Hispanic ethnicity, side-by-side great arteries, and urgent or emergent operation were significantly associated with the composite outcome of reoperation or mortality. There were no coronary interventions after ASO, and the incidence of moderate or greater aortic insufficiency was 2.1% at hospital discharge and 1.5% in follow-up. CONCLUSIONS: Closed coronary transfer during ASO has excellent short-term and midterm results. Despite variable and often complex coronary anatomy, coronary ischemic events after ASO are avoidable. Closed coronary transfer has a low risk of aortic valve injury or insufficiency.

Repair of Anomalous Single Coronary Artery From the Pulmonary Artery (ASCAPA).

We describe the management of an infant presenting with severe heart failure at 6 weeks of age found to have an anomalous single coronary artery originating from the main pulmonary artery (MPA). This patient was transferred to our hospital and ultimately had their coronary artery translocated to the ascending aorta successfully. Preoperative severe left ventricular (LV) dysfunction and moderate/severe mitral regurgitation (MR) improved to normal function and mild-to-moderate MR 6 weeks postrepair. Three-dimensional CT reconstructions proved valuable and allowed for accurate preoperative planning leading to successful coronary transfer.

Staged Repair of Van Praagh Truncus Type A3.

Van Praagh (VP) A3 variant of truncus arteriosus (or common arterial trunk) is defined by only one pulmonary artery (usually the right) originating from the common trunk, while the other lung is supplied either by collaterals or a pulmonary artery arising from the aortic arch. This report describes a staged approach to manage a VP-A3 variant truncus arteriosus with ductal origin of the left pulmonary artery (LPA), a hypoplastic right pulmonary artery, and cyanosis. Initially, the ductal portion of the proximal LPA was stented with a Resolute Onyx drug-eluting stent. The pulmonary arteries grew and at four months of age had an acceptable McGoon ratio and Nakata index. The patient then underwent repair which included unifocalization of the branch pulmonary arteries, closure of the ventricular septal defect, and placement of a right ventricle-to-pulmonary artery homograft conduit.

Autologous Patch Angioplasty of a Giant Right Coronary Artery Aneurysm and Coronary Stenosis in Kawasaki Disease.

We describe our management of a 2-year-old patient with Kawasaki disease with a giant proximal right coronary artery (RCA) aneurysm and a >99% RCA ostial stenosis. After median sternotomy and cardioplegic arrest of the heart, we opened the aorta and cut into the RCA ostium past the stenosis and giant aneurysm. The RCA was reconstructed with an autologous pericardial patch. Cross-clamp and cardiopulmonary bypass times of 84 minutes and 114 minutes, respectively, were required. Our approach avoids mammary harvesting and grafting in such small patients while successfully treating ischemia and hopefully prevents further aneurysmal dilation over time.

Repair of Anomalous Right Coronary Artery From the Pulmonary Artery Using the Modified Trapdoor Technique.

BACKGROUND: Anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA) is rare. Unique anatomical characteristics observed include tethering secondary to the extensive collateral vessels, severe native coronary tortuosity, and massive dilation of the coronary arteries. This requires specific technical consideration to ensure safe translocation. METHODS: A single-center retrospective review of six patients with ARCAPA was performed. Echocardiographic and computerized tomography scan data were analyzed for anatomical and functional cardiac characteristics. Operative techniques were analyzed, which reflected an evolution toward a modified-trapdoor technique. RESULTS: Five children presented with asymptomatic murmurs and one adult patient with unstable angina. All patients underwent successful surgical correction. The modified trapdoor technique provided the most ideal geometry for coronary transfer secondary to its anatomical characteristics. Two patients had coronary button transfers above the sinotubular junction using vertical stab incisions, one had the button implanted after excising part of the aortic wall, and last three patients had modified trapdoor incisions. Mean cardiopulmonary bypass and cross-clamp times were 170 ± 27 minutes and 99.5 ± 29 minutes respectively. The average hospital stay was five days and there were no mortalities. CONCLUSIONS: Anomalous right coronary from the pulmonary artery's unique anatomical characteristics require a coronary transfer technique different from that performed in aortic root replacement. In some respects, our modified technique resembles coronary transfers used in difficult arterial switch operations. The use of a modified trapdoor incision simplifies coronary transfer and may minimize coronary kinking and subsequent complications related to coronary transfer.

EncoMPASS: an online database for analyzing structure and symmetry in membrane proteins.

The EncoMPASS online database (http://encompass.ninds.nih.gov) collects, organizes, and presents information about membrane proteins of known structure, emphasizing their structural similarities as well as their quaternary and internal symmetries. Unlike, e.g. SCOP, the EncoMPASS database does not aim for a strict classification of membrane proteins, but instead is organized as a protein chain-centric network of sequence and structural homologues. The online server for the EncoMPASS database provides tools for comparing the structural features of its entries, making it a useful resource for homology modeling and active site identification studies. The database can also be used for inferring functionality, which for membrane proteins often involves symmetry-related mechanisms. To this end, the online database also provides a comprehensive description of both the quaternary and internal symmetries in known membrane protein structures, with a particular focus on their orientation relative to the membrane.

Successful recycling of a previously transplanted heart: another option for limited resources.

We report a case of successful reuse of a previously transplanted heart. The organ was retransplanted 16 days after the initial transplantation into a 60-year-old man who had previously received a left ventricular assist device.