Surgical Repair of Common Arterial Trunk With Ventriculoarterial Septal Defect and Dual Orifice Truncal Valve.

We present a case of a rare example of a ventriculo-arterial septal defect found in a patient with a common arterial trunk, with balanced aortic and pulmonary components, but with separate valvar orifices within the common truncal valve. We managed the lesion using a two-patch approach. Performing a palliative procedure to relieve the elevated right ventricular pressure aided in the preservation of the pulmonary component of the common valve. We validated the success of the technique using postoperative computerized tomography and four-dimensional flow magnetic resonance imaging.

Complex Atrial Baffling Procedures in Left Isomerism With Right- and Left-Hand Topology.

We describe complex atrial baffling procedures in the setting of left isomerism with right-hand as opposed to left-handed ventricular topology. An appropriate understanding of the connections of the systemic and pulmonary veins, along with the internal atrial anatomy, as revealed using 3D printing, allowed for successful biventricular repair.

An Unusual Presentation of Double-Outlet Right Atrium.

We describe an unusual example of double-outlet right atrium with separate atrioventricular junctions. The straddling and overriding tricuspid valve had two orifices, and the mitral valve was morphologically normal. An appropriate understanding of the morphology of the atrioventricular junctions, the valves, and the subvalvar apparatus, along with the location of the atrioventricular conduction axis, allowed for successful biventricular repair.

Surgical repair of interrupted right-sided cervical aortic arch with hypoplasia of the descending thoracic aorta in a child with PHACE syndrome.

Obstruction of a right cervical aortic arch in association with hypoplasia of the descending aorta is a rare congenital cardiac malformation. We report the case of a 6-month-old boy with posterior fossa anomalies, hemangioma, arterial anomalies, cardiac anomalies and eye anomalies (PHACE) syndrome and interruption of a right-sided cervical aortic arch. The descending thoracic aorta in the child had a long hypoplastic segment and the patient also had small ventricular septal defect and pulmonary valve stenosis. The surgical technique of reconstruction of the aortic arch and the descending thoracic aorta through a median sternotomy is described.

Identifying Anomalies of Systemic Venous Drainage: Systemic Venous Anomalies; Atrial Morphology.

So as to produce totally anomalous systemic venous connection, all of the systemic venous tributaries, along with the coronary sinus, should be connected with the morphologically left atrium. Previous descriptions of this rare constellation of anomalous connections of the systemic venous tributaries of the heart have been compromised by the inclusion of individuals having isomeric atrial appendages. In these settings, most frequently, the totally, or almost totally, anomalous systemic venous connections are associated with a sinus venosus defect. It is the anomalous pulmonary venous connections that then create a venovenous bridge, which permits the systemic venous tributaries to drain into the morphologically left atrium, even though they may be predominantly connected to the right atrium. More rarely, it is feasible for the primary atrial septum to develop so as to leave the systemic venous sinus in direct connection with the body of the morphologically left, rather than the morphologically right, atrium. We report a series of patients potentially falling into the category of anomalous systemic venous connections. The findings show a spectrum from partially to totally anomalous connections, with some better interpreted on the basis of anomalous drainage. Included in our cases, nonetheless, is an autopsied example of totally anomalous systemic venous connection produced by an abnormal location of the primary atrial septum. We discuss the potential morphogenesis for this finding. We emphasize the distinction that needs to be made between anomalous systemic venous connections and anomalous systemic venous drainage.

A Newly Detected Left Ventricular Mass Following A Complex Intracardiac Repair.

Appearance of unexpected masses in the chambers of the heart during cardiac surgery can be intriguing. We report the case of a mass in the left ventricle that appeared at the time of separation from cardiopulmonary bypass in a child after a complex intracardiac repair. The child presented for surgery to a tertiary care hospital in Muscat, Oman, in 2022. Prior to the surgical repair the mass was not appreciated by echocardiography. An intraventricular baffle was used to divert left ventricular blood flow towards the outflow tract, after which an intraventricular "mass" was observed. Intraoperative transoesophageal echocardiography identified the mass as a portion of the interventricular septum that was located between the inlet and outlet ventricular septal defects.

Blalock-Taussig Shunt versus Ductal Stenting as Palliation for Duct-Dependent Pulmonary Circulation.

Objectives: There is limited data published from outside North America and Europe comparing the outcomes of a modified Blalock-Taussig shunt (MBTS) and ductal stenting as the first palliative procedure for infants with duct-dependent pulmonary circulation. This study reports the National Heart Center's, in Muscat, Oman, experience in comparing the outcomes of these 2 interventions. Methods: This retrospective study included all infants with duct-dependent pulmonary circulation who received either a MBTS or ductal stenting from 2016-2019. The primary outcomes were death or re-interventions. Secondary outcomes included death, subsequent re-interventions, survival to subsequent surgical intervention, survival to hospital discharge, post-procedural mechanical ventilation and duration of intensive care unit stay. Results: A total of 71 patients were included in the study, 33 (46%) of whom received ductal stenting. The prevalence of the primary outcome (death or re-intervention) in the patent ductus arteriosus (PDA) stent group was 54.5% versus 31.6% in the MBTS group but this was not statistically significant (P = 0.06). There was no difference between the 2 groups in terms of time to next surgical intervention (P = 0.233). The PDA stent group had shorter post-procedural, mechanical ventilation and intensive care unit stay durations (P <0.05). Syndromic patients were at higher risk of mortality compared to non-syndromic patients. Conclusion: MBTS and ductal stenting are both acceptable modalities as a palliative intervention for infants with duct-dependant pulmonary circulation. Syndromic patients are at higher risk of mortality. This can be considered an important factor for patient selection.

Bronchial decompression following repair of absent pulmonary valve: Fine-tuning by procedural fiberoptic bronchoscopy.

Marked aneurysmal dilation of the central and branch pulmonary arteries in utero in patients with tetralogy of Fallot with absent pulmonary valve can often exhibit extrinsic compression of the trachea and bronchi. The major morbidity in these patients remains postoperative ventilation issues. This case report highlights the role of intraoperative bronchoscopy in providing guidance for obtaining optimal bronchial decompression that was achieved by an initial pulmonary arteriopexy followed by an aortopexy.

Clinical, cellular, and molecular characterisation of cardiac rhabdomyoma in tuberous sclerosis.

BACKGROUND: Rhabdomyoma is the most common cardiac tumour in children. It is usually associated with tuberous sclerosis complex caused by mutations in TSC-1 or TSC-2 genes. This tumour typically regresses by unknown mechanisms; however, it may cause inflow or outflow obstruction that necessitates urgent surgery. Here we investigate the clinical features and the genetic analysis of patients with tuberous sclerosis complex presenting with large rhabdomyoma tumours. We also investigate the potential role of autophagy and apoptosis in the pathogenesis of this tumour. METHODS: All the patients with cardiac rhabdomyoma referred to Aswan Heart Centre from 2010 to 2018 were included in this study. Sanger sequencing was performed for coding exons and the flanking intronic regions of TSC1 and TSC2 genes. Histopathological evaluation, immunohistochemistry, and western blotting were performed with P62, LC3b, caspase3, and caspase7, to evaluate autophagic and apoptotic signaling. RESULTS: Five patients were included and had the clinical features of tuberous sclerosis complex. Three patients, who were having obstructive tumours, were found to have pathogenic mutations in TSC-2. The expression of two autophagic markers, P62 and LC3b, and two apoptotic markers, caspase3 and caspase7, were increased in the tumour cells compared to normal surrounding myocardial tissue. CONCLUSION: All the patients with rhabdomyoma were diagnosed to have tuberous sclerosis complex. The patients who had pathogenic mutations in the TSC-2 gene had a severe disease form necessitating urgent intervention. We also demonstrate the potential role of autophagy and apoptosis as a possible mechanism for tumourigenesis and regression. Future studies will help in designing personalised treatment for cardiac rhabdomyoma.

Congenital Coronary Aneurysm: Unusual Presentation of Myocardial Ischemia in Children.

Coronary artery aneurysms in children are usually associated with inflammatory disease such as Kawasaki disease or connective tissue disease. Congenital coronary aneurysm is a rare entity with few case reports published in the literature. We report an unusual case of congenital coronary aneurysm in an 11-year-old boy presented to our center with an ischemic cardiac event. Further investigations including computed tomography scan, cardiac magnetic resonance imaging, and coronary angiography revealed a large aneurysm arising from the proximal segment of left anterior descending (LAD) artery. Surgical repair was done including aneurysm resection and roofing the LAD artery using autologous saphenous vein patch.

Urotensin II, urotensin-related peptide, and their receptor in aortic valve stenosis.

OBJECTIVES: Aortic valve stenosis (AVS) is the most common cause of surgical valve replacement worldwide. The vasoactive peptide urotensin II (UII) is upregulated in atherosclerosis and several other cardiovascular diseases; however, its role in the pathogenesis of AVS remains to be determined. Here, we investigated the expression of UII, urotensin-related peptide (URP), and the urotensin receptor (UT) and the role this system plays in AVS. METHODS: Immunohistochemistry and reverse-transcriptase polymerase chain reaction were used to examine the cellular localization and mRNA expression, of UII, URP, and UT in calcified and noncalcified aortic valves. Human aortic valve interstitial cells were isolated from normal valves and treated with UII or URP, and changes in cell proliferation, cholesterol efflux, calcium deposition, and ß-catenin translocation were assessed. RESULTS: The mRNA expression of UII, URP, and UT was significantly greater in patients with AVS. There was abundant presence of UII, URP, and UT immunostaining in diseased compared with nondiseased valves and correlated significantly with presence of calcification (P < .0001) and fibrosis (P < .0001). Treating human aortic valve interstitial cells with UII or URP significantly increased cell proliferation (P < .0001) and decreased cholesterol efflux (P = .0011 and P = .0002, respectively). UII also significantly reduced ABCA1 protein expression (P = .0457) and increased ß-catenin nuclear translocation (P < .0001) and mineral deposition (P < .0001). CONCLUSIONS: Together, these data suggest that the urotensin system plays a role in the pathogenesis of AVS and warrants further investigation.

Cor Triatriatum Sinister (Divided Left Atrium): Histopathologic Features and Clinical Management.

BACKGROUND: Cor triatriatum sinister (CTS), or divided left atrium, is a rare congenital cardiac disease in which the left atrium is divided into 2 chambers by a fibromuscular diaphragm that will cause blood flow obstruction to the left ventricle. Recent animal studies suggested the role of hyaluronidase-2 (HYAL-2) deficiency as a risk factor for developing CTS. The histopathologic features of this diaphragm and our surgical experience with the management of this disease are reviewed. METHODS: Ten patients underwent surgical correction of CTS between 2010 and 2018. All patients had complete clinical and imaging evaluation. The fibromuscular diaphragms were histologically evaluated with myosin, troponin, vimentin, smooth muscle actin, and HYAL-2 to characterize the structure of the CTS diaphragm. RESULTS: All patients underwent excision of CTS diaphragm using cardiopulmonary bypass with no early mortality. Most patients had the classic form of CTS in which the diaphragm separates the pulmonary and the vestibular chambers with no atrial septal defect. The histologic studies demonstrated the presence of fibrous, mesenchymal cells, along with cardiac muscle cells, at the site of membrane attachments. HYAL-2 enzyme was expressed in the CTS diaphragm. CONCLUSIONS: Surgical repair of CTS provides satisfactory results with low risk of death. Our histologic studies revealed the cellular composition of the CTS diaphragm. HYAL-2 deficiency may not explain the pathogenesis of CTS, and further studies are needed to evaluate the complex mechanisms involved in the development of this disease.

Transection and Relocation of Anomalous Left Coronary Artery After Aborted Sudden Cardiac Death.

Anomalous origin of the left main coronary artery from the right coronary sinus is associated with sudden cardiac death. We present a young adult who was diagnosed with this anomaly after an aborted sudden cardiac death. He underwent a complete anatomical repair by translocating the left coronary artery to the left coronary sinus of Valsalva, with excellent 10 years outcome.

Expression of the Frizzled receptors and their co-receptors in calcified human aortic valves.

The cellular mechanisms that induce calcific aortic stenosis are yet to be unraveled. Wnt signaling is increasingly being considered as a major player in the disease process. However, the presence of Wnt Frizzled (Fzd) receptors and co-receptors LRP5 and 6 in normal and diseased human aortic valves remains to be elucidated. Immunohistochemistry and quantitative polymerase chain reaction were used to determine Fzd receptor expression in normal and calcified human aortic valve tissue, as well as human aortic valve interstitial cells (HAVICs) isolated from calcified and normal human aortic valves. There was significantly higher mRNA expression of 4 out of the 10 Fzd receptors in calcified aortic valve tissues and 8 out of the 10 in HAVICs, and both LRP5/6 co-receptors in calcified aortic valves (P < 0.05). These results were confirmed by immunohistochemistry, which revealed abundant increase in immunoreactivity for Fzd3, 7, and 8, mainly in areas of lipid core and calcified nodules of diseased aortic valves. The findings of abundant expression of Fzd and LRP5/6 receptors in diseased aortic valves suggests a potential role for both canonical and noncanonical Wnt signaling in the pathogenesis of human aortic valve calcification. Future investigations aimed at targeting these molecules may provide potential therapies for aortic valve stenosis.

Role of Noncanonical Wnt Signaling Pathway in Human Aortic Valve Calcification.

OBJECTIVE: The mechanisms underlying the pathogenesis of aortic valve calcification remain unclear. With accumulating evidence demonstrating that valve calcification recapitulates bone development, the crucial roles of noncanonical Wnt ligands WNT5a, WNT5b, and WNT11 in osteogenesis make them critical targets in the study of aortic valve calcification. APPROACH AND RESULTS: Using immunohistochemistry, real-time qPCR, Western blotting, and tissue culture, we examined the tissue distribution of WNT5a, WNT5b, and WNT11 in noncalcified and calcified aortic valves and their effects on human aortic valve interstitial cells (HAVICs). Only focal strong immunostaining for WNT5a was seen in and around areas of calcification. Abundant immunostaining for WNT5b and WNT11 was seen in inflammatory cells, fibrosis, and activated myofibroblasts in areas of calcified foci. There was significant correlation between WNT5b and WNT11 overall staining and presence of calcification, lipid score, fibrosis, and microvessels (P<0.05). Real-time qPCR and Western blotting revealed abundant expression of both Wnts in stenotic aortic valves, particularly in bicuspid valves. Incubation of HAVICs from noncalcified valves with the 3 noncanonical Wnts significantly increased cell apoptosis and calcification (P<0.05). Treatment of HAVICs with the mitogen-activated protein kinase-38ß and GSK3ß inhibitors significantly reduced their mineralization (P<0.01). Raman spectroscopy identified the inorganic phosphate deposits as hydroxyapatite and showed a significant increase in hydroxyapatite deposition in HAVICs in response to WNT5a and WNT11 (P<0.05). Similar crystallinity was seen in the deposits found in HAVICs treated with Wnts and in calcified human aortic valves. CONCLUSIONS: These findings suggest a potential role for noncanonical Wnt signaling in the pathogenesis of aortic valve calcification.

Sustained release of milrinone delivered via microparticles in a rodent model of myocardial infarction.

OBJECTIVE: The aim of the present study was to construct a new drug delivery system for milrinone using microparticles. This novel technology enhances drug bioavailability and decreases toxicity, with future implications for the treatment of end-stage heart failure. METHODS: Polylactic-co-glycolic acid microparticles (PLGA-MPs) loaded with milrinone were prepared using a double emulsion-solvent evaporation technique. In vitro release kinetics was evaluated at physiologic conditions. A total of 24 female Lewis rats underwent left coronary artery ligation. One week after ligation, all rats were randomized to 1 of 3 groups (n=8 per group). Group I received an intravenous injection of PLGA-MPs alone; group II, a bolus intravenous injection of milrinone; and group III an intravenous injection of milrinone-PLGA-MPs. All injections were administrated slowly by way of the tail vein over 10 minutes. Transthoracic echocardiography, noninvasive heart rate monitoring, and blood pressure measurements were performed at different predetermined intervals before and for 24 hours after the injection. All rats survived for 24 hours and were then killed by euthanasia. Serum plasma was taken for cytokine assays and determination of milrinone levels using high-performance liquid chromatography. RESULTS: Group III had a significantly greater left ventricular ejection fraction at 90 minutes and 3, 6, and 12 hours after treatment compared with the other groups. The milrinone plasma level was significantly greater in group III than in the other groups (group I, 0 ng/mL; group II, 1.7±2.4 ng/mL; group III, 9.1±2.2 ng/mL; P<.05). The intercellular adhesion molecule and cytokine-induced neutrophil chemoattractant-1 levels were significantly lower in group III than in the other 2 groups (P<.05). CONCLUSIONS: Drug encapsulation using microparticles can prolong the effects of milrinone. We propose a new strategy for future drug delivery in patients with end-stage heart failure.