Partial Heart Transplant in a Neonate With Irreparable Truncal Valve Dysfunction.

Importance: The treatment of neonates with irreparable heart valve dysfunction remains an unsolved problem because there are no heart valve implants that grow. Therefore, neonates with heart valve implants are committed to recurrent implant exchanges until an adult-sized valve can fit. Objective: To deliver the first heart valve implant that grows. Design, Setting, and Participants: Case report from a pediatric referral center, with follow-up for more than 1 year. Participants were a recipient neonate with persistent truncus arteriosus and irreparable truncal valve dysfunction and a donor neonate with hypoxic-ischemic brain injury. Intervention: First-in-human transplant of the part of the heart containing the aortic and pulmonary valves. Main Outcomes and Measures: Transplanted valve growth and hemodynamic function. Results: Echocardiography demonstrated adaptive growth and excellent hemodynamic function of the partial heart transplant valves. Conclusions and Relevance: In this child, partial heart transplant delivered growing heart valve implants with a good outcome at age 1 year. Partial heart transplants may improve the treatment of neonates with irreparable heart valve dysfunction.

Cardiac forces regulate zebrafish heart valve delamination by modulating Nfat signaling.

In the clinic, most cases of congenital heart valve defects are thought to arise through errors that occur after the endothelial-mesenchymal transition (EndoMT) stage of valve development. Although mechanical forces caused by heartbeat are essential modulators of cardiovascular development, their role in these later developmental events is poorly understood. To address this question, we used the zebrafish superior atrioventricular valve (AV) as a model. We found that cellularized cushions of the superior atrioventricular canal (AVC) morph into valve leaflets via mesenchymal-endothelial transition (MEndoT) and tissue sheet delamination. Defects in delamination result in thickened, hyperplastic valves, and reduced heart function. Mechanical, chemical, and genetic perturbation of cardiac forces showed that mechanical stimuli are important regulators of valve delamination. Mechanistically, we show that forces modulate Nfatc activity to control delamination. Together, our results establish the cellular and molecular signature of cardiac valve delamination in vivo and demonstrate the continuous regulatory role of mechanical forces and blood flow during valve formation.

Long-term outcomes of truncus arteriosus repair: A modulated renewal competing risks analysis.

OBJECTIVE: In this study, we sought to identify independent risk factors for mortality and reintervention after early surgical correction of truncus arteriosus using a novel statistical method. METHODS: Patients undergoing neonatal/infant truncus arteriosus repair between January 1984 and December 2018 were reviewed retrospectively. An innovative statistical strategy was applied integrating competing risks analysis with modulated renewal for time-to-event modeling. RESULTS: A total of 204 patients were included in the study. Mortality occurred in 32 patients (15%). Smaller right ventricle to pulmonary artery conduit size and truncal valve insufficiency at birth were significantly associated with overall mortality (right ventricle to pulmonary artery conduit size: hazard ratio, 1.34; 95% confidence interval, 1.08-1.66, P = .008; truncal valve insufficiency: hazard ratio, 2.5; 95% confidence interval, 1.13-5.53, P = .024). truncal valve insufficiency at birth, truncal valve intervention at index repair, and number of cusps (4 vs 3) were associated with truncal valve reoperations (truncal valve insufficiency: hazard ratio, 2.38; 95%, confidence interval, 1.13-5.01, P = .02; cusp number: hazard ratio, 6.62; 95% confidence interval, 2.54-17.3, P < .001). Right ventricle to pulmonary artery conduit size 11 mm or less was associated with a higher risk of early catheter-based reintervention (hazard ratio, 1.54; 95% confidence interval, 1.04-2.28, P = .03) and reoperation (hazard ratio, 1.96; 95% confidence interval, 1.33-2.89, P = .001) on the right ventricle to pulmonary artery conduit. CONCLUSIONS: Smaller right ventricle to pulmonary artery conduit size and truncal valve insufficiency at birth were associated with overall mortality after truncus arteriosus repair. Quadricuspid truncal valve, the presence of truncal valve insufficiency at the time of diagnosis, and truncal valve intervention at index repair were associated with an increased risk of reoperation. The size of the right ventricle to pulmonary artery conduit at index surgery is the single most important factor for early reoperation and catheter-based reintervention on the conduit.

Systemic thrombolysis in a patient with massive acute valvular thrombosis.

Prosthetic valve thrombosis (PVT) is considered an exceptionally rare condition, often associated with pro-thrombotic factors or suboptimal anticoagulant therapy. Guidelines recommend emergent surgery for patients with left heart valve prosthetic thrombosis who present in cardiogenic shock, and systemic thrombolysis is reserved in scenarios where surgery is not immediately available. However, several factors may affect surgical prognosis and are overlooked by current recommendations. We describe the case of a 34-year-old female who presented in the emergency department with cardiogenic shock and acute pulmonary edema due to acute valve thrombosis.

Persistent common arterial trunk with hexaleaflet truncal valve and intact ventricular septum.

We report a case of a 3-week-old infant who presented a heart murmur and low oxygen saturation. An echocardiography was performed and presented a common arterial trunk type B4 with an interrupted aortic arch and intact ventricular septum. We describe the surgical management and short-term follow-up.

ADAMTS19-associated heart valve defects: Novel genetic variants consolidating a recognizable cardiac phenotype.

Recently, ADAMTS19 was identified as a novel causative gene for autosomal recessive heart valve disease (HVD), affecting mainly the aortic and pulmonary valves. Exome sequencing and data repository (CentoMD) analyses were performed to identify patients with ADAMTS19 variants (two families). A third family was recognized based on cardiac phenotypic similarities and SNP array homozygosity. Three novel loss of function (LoF) variants were identified in six patients from three families. Clinically, all patients presented anomalies of the aortic/pulmonary valves, which included thickening of valve leaflets, stenosis and insufficiency. Three patients had (recurrent) subaortic membrane, suggesting that ADAMTS19 is the first gene identified related to discrete subaortic stenosis. One case presented a bi-commissural pulmonary valve. All patients displayed some degree of atrioventricular valve insufficiency. Other cardiac anomalies included atrial/ventricular septal defects, persistent ductus arteriosus, and mild dilated ascending aorta. Our findings confirm that biallelic LoF variants in ADAMTS19 are causative of a specific and recognizable cardiac phenotype. We recommend considering ADAMTS19 genetic testing in all patients with multiple semilunar valve abnormalities, particularly in the presence of subaortic membrane. ADAMTS19 screening in patients with semilunar valve abnormalities is needed to estimate the frequency of the HVD related phenotype, which might be not so rare.

Ventriculoatrial malalignment in atrioventricular septal defect resulting in uniatrial biventricular connection: surgical options.

BACKGROUND: Uniatrial biventricular connection (UBC) is a rare cardiovascular anomaly characterized by absence of one atrioventricular connection and drainage of the other atrium via a solitary atrioventricular valve into both ventricles. The absent atrioventricular connection may affect either the left or right atrium. Because of the absence of one atrioventricular connection hearts with UBC have been classified among functionally univentricular hearts requiring palliative treatment according to the Fontan principle. AIMS/OBJECTIVE: We report two further patients with UBC. In one of these patients careful echocardiographic examination of the atrioventricular junction in early infancy revealed the possibility of biventricular repair based on the favorable anatomy of the atrioventricular valve and balanced ventricles in the presence of an inlet ventricular septal defect (VSD). CASE PRESENTATIONS: Both patients presented in the neonatal period for evaluation of complex congenital heart disease. The anatomy of the atrioventricular valves in our patients was indistinguishable from atrioventricular septal defects exhibiting the morphology of a common valve with superior and inferior bridging leaflets. The common atrioventricular valve was connected exclusively to the right atrium draining into both ventricles while the left atrium drained into the right atrium via a secundum atrial septal defect. In one of our patients biventricular repair with good longterm-result was performed by reseptation of the atria, patch repair of the VSD and septation of the atrioventricular valve. The second patient underwent univentricular palliation according to the Fontan principle. DISCUSSION/CONCLUSION: The echocardiographic findings in our patients suggest that at least some patients with UBC represent a variant of atrioventricular septal defects associated with extreme ventriculoatrial malalignment resulting in fusion of the deviated primary atrial septum with the lateral aspect of the atrioventricular junction. This offers the option of septation of the common atrioventricular valve and biventricular repair in patients with adequate size of both ventricles. Exact echocardiographic analysis of the morphology of the atrioventricular valve is essential to distinguish these patients with a morphologically common atrioventricular valve in early infancy from other variants of absent atrioventricular connection and to select those who are suitable for biventricular repair.

Williams-Beuren Syndrome: The Role of Cardiac CT in Diagnosis.

Williams-Beuren syndrome is a multisystem genetic disorder associated with cardiovascular abnormalities, the most common of which is some variation of arterial stenosis. We describe a case of Williams-Beuren syndrome with multiple cardiovascular structural and arterial abnormalities and demonstrate the unique role of cardiac computed tomography in diagnosis.

Left Ventricle to Right Atrial Shunt Associated With Ventricular-Atrial Malalignment, Double Outlet Right Atrium, and Subaortic Membrane.

We describe an asymptomatic 7-year-old boy who was taken to the operating room for repair of a subaortic membrane and possible Gerbode's defect. He was found to have a double outlet right atrium associated with an accessory atrioventricular valve in addition to a small atrial septal defect and subaortic membrane. Regurgitant flow through this accessory valve led to the left ventricle to right atrial shunt that was seen on preoperative ECHO. The atrial septal defect was repaired and a baffle was used to isolate blood flow across the accessory valve from the left atrium to the left ventricle. The patient was discharged on postoperative day 4 and has been doing well 2 years postoperatively.

Persistent truncus arteriosus with absent semilunar valve in first trimester.

Persistent truncus arteriosus (PTA) is a relatively uncommon congenital heart disease, accounting for approximately 0.7-1.4% of all congenital cardiac abnormalities worldwide. PTA is usually accompanied by a single semilunar valve, with leaflets ranging from one to six in number. However, absent semilunar valve (ASV) is rarely seen in PTA. Here, we report a case of prenatally diagnosed PTA accompanied by ASV (PTA-ASV) confirmed by postmortem autopsy.

Evaluation of septal insertion of atrioventricular valves in fetuses by postmortem 4.7 Tesla cardiac MRI: A feasibility study.

PURPOSE: The purpose of this study was to compare non-invasive high-spatial-resolution postmortem cardiac magnetic resonance imaging (MRI) and autopsy findings for evaluating the septal insertion of atrioventricular valves in fetuses. MATERIALS AND METHODS: Five fetal heart specimens including two normal hearts, one heart with complete atrioventricular septal defect (AVSD) and two hearts with linear insertion of atrioventricular valves (LIAVV; gestational age 17 to 34 weeks) were studied with cardiac MRI using a 4.7 T MRI scanner without sample preparation. Three (3D) and two-dimensional (2D) turbo-RARE (rapid imaging with refocused echoes) sequences in four-chamber and left-ventricular long-axis planes were obtained with a minimal isotropic/in-plane resolution of 156µm. Nonparametric tests were performed to compare the distance between insertions of medial leaflets of the atrioventricular valves and the inlet/outlet distance ratio between MRI and autopsy findings in normal, complete AVSD and with linear insertion of atrioventricular valves (LIAVV) fetal hearts. RESULTS: Despite apparent differences between LIAVV/normal hearts, no significant differences were found between differential insertion of medial leaflets and inlet/outlet distance ratios with both techniques. Very good to excellent reliability between both techniques was found for differential insertion (ICC: 87.2%; 95% CI: -21.7%, 99.1%) (P=0.963) and inlet/outlet distance ratio (ICC 98.3%; 95%CI: 85.2%, 99.8%) (P=0.537) measurements. CONCLUSION: Postmortem cardiac MRI could replace autopsy for assessing normal or abnormal septal insertion of atrioventricular valves in fetuses without requiring specific preparation of the heart.

Hybrid strategies for high-risk non-hypoplastic left heart syndrome patients.

Single-stage repair of complex cardiac abnormalities in high-risk neonates presents formidable challenges. The majority of hybrid strategies involving bilateral pulmonary artery banding (bPAB) with or without patent ductus arteriosus (PDA) stenting is described in the setting of hypoplastic left heart syndrome. We present a series of cases describing two-stage repair with initial palliative hybrid procedures involving bPAB with or without PDA stenting. This allows weight gain and stabilization of circulation before complete repair, provides good results, and may overcome risk factors associated with single-stage repair in neonates.

Polyvalvular heart disease syndrome.

An adult case of polyvalvular heart disease syndrome diagnosed in an adult is presented. The characteristic facies and echocardiographic features of this rare autosomal dominant connective tissue disorder are presented.