Comparing flow and pulmonary artery growth post-patent ductus arteriosus stenting in patients with ductal-dependent pulmonary flow using 4D magnetic resonance imaging.

Aims: The 4D magnetic resonance imaging (4D-flow MRI) provides a qualitative and quantitative assessment of cardiovascular structures and processes. 4D-flow MRI was used to study pulmonary flow in post-patent ductus arteriosus (PDA) stent insertion in duct-dependent pulmonary flow neonates at baseline (PDA stent insertion) and after 6 months, and also, to evaluate the effect of flow dynamics on the growth of pulmonary arteries (PAs). Methods and results: This prospective observational study included neonates with ductus arteriosus-dependent pulmonary circulation who underwent ductal stenting between June 2021 and November 2022. Cardiac 4D-flow MRI and magnetic resonance angiography were conducted in two phases; after the deployment of the PDA stent during the neonatal period and after 6 months from stent deployment. Eight neonates were recruited, but only five completed both scans. A total of 10 PAs were evaluated during each phase. The median left PA (LPA) and right PA (RPA) diameters and indexed flow for LPA and RPA were evaluated. The growth rate of LPA was observed to be lower than that of RPA (percentage diameter increase: 74 vs. 153%). LPA Z-score was lower than RPA. Indexed flow in both LPA and RPA showed a reduction in the 6-month scan, which was consistent with reduced stent patency. Conclusion: 4D-flow cardiac MRI showed different growth rates and reduced flow between LPA and RPA post-PDA stent. These insights can aid in future management decisions.

Systemic venous anomalies in a child with a vein of Galen.

We describe our findings in a child with a vein of Galen malformation, in whom the right superior caval and the azygos veins drained into the roof of the morphologically left atrium. A persistent left superior caval vein drained into the morphologically right atrium through the coronary sinus. The additional presence of dual brachiocephalic veins permitted the deployment of a multifunctional ventricular septal defect occluder device to occlude the right superior caval vein, correcting the right-to-left shunt. This also prevented azygos venous drainage into the left atrium.

Recurrent Infective Endocarditis in an Adolescent due to Streptococcus agalactiae: A Rare Presentation of a Common Pathogen.

Streptococcus agalactiae is known to cause invasive infections in risk groups such as pregnant women, newborns, and immunosuppressed patients but it is uncommon in older children. We describe a case of recurrent infective endocarditis due to S. agalactiae in an 11-year-old boy with Loeys-Dietz syndrome who was successfully treated with long-term antimicrobial therapy for one year.

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.

Large aortopulmonary collateral artery exclusively supplying the lower lobe of left lung in an infant with common arterial trunk with aortic dominance with confluent pulmonary arteries.

INTRODUCTION: Common arterial trunk with aortic dominance has well-developed bilateral pulmonary arterial arborization without any essential major aortopulmonary collateral arteries (MAPCAs), whereas "solitary" arterial trunk is characterized by collateral arterial supply to all bronchopulmonary segments and absent pulmonary arteries. CASE REPORT: We report a term female neonate with common arterial trunk with aortic dominance with confluent pulmonary arteries with a large MAPCA as the sole blood supply to the lower lobe of the left lung. RESULTS: Initial diagnostic workup missed this MAPCA from the descending thoracic aorta. It was suspected during surgery due to massive left atrial return and confirmed by cardiac catheterization study in the early postoperative period and treated successfully by unifocalization. DISCUSSION: A large essential MAPCA supplying an entire lobe in the common arterial trunk with aortic dominance has not been described. It can present as heart failure and inability to wean off the ventilator in the early postoperative period following intracardiac repair. CONCLUSION: This is a case hitherto undescribed and possibly falling outside the well-entrenched classifications of the common arterial trunk and a large MAPCA could be an addition to the list of lesion modifiers. Our experience with this case underlines the importance of a thorough and open-minded approach to the initial imaging assessment of even well-described conditions.

Chronic Q Fever Endocarditis in an Omani Child: The First Pediatric Case Report from Oman.

Q fever endocarditis is the most common presentation of chronic infection of Coxiella burnetii, but it rarely occurs in the pediatric age group. We report the first case of Q fever endocarditis in an Omani child. The affected 11-year-old female lives in the Al Batinah governorate in the north of Oman and was known to have congenital heart disease. She presented with features of chronic blood culture-negative endocarditis. The C. burnetii infection was confirmed with the indirect immunofluorescence assay. The patient responded well to a combination of doxycycline and hydroxychloroquine therapy.

Percutaneous Closure of Ventricular Septal Defects in 116 Patients: Experience with different devices.

OBJECTIVES: This study aimed to review the experience with percutaneous closure of ventricular septal defects (VSDs) at the National Heart Center (NHC) in Muscat, Oman. METHODS: This retrospective study was conducted from November 2008 to December 2017. Patients' electronic medical records were reviewed to identify their clinical, imaging and interventional data before and after the procedure and on the last follow-up. RESULTS: A total of 116 patients, the majority of which were female (58%), underwent 118 percutaneous procedures for VSD closure at a median age of 3.54 years (range: 0.25-33 years) and a median weight of 12 kg (range: 3.5-78 kg). The mean diameter of the VSDs as determined by transoesophageal echocardiogram was 5.6 ± 1.9 mm (n = 105). The commonest type of VSD was perimembranous (n = 75, 63.5%). Devices were successfully placed during 111 (94.1%) procedures in 109 (94.0%) patients, with the commonest device being a Amplatzer™ duct occluder I (St. Jude Medical, Little Canada, Minnesota, USA; n = 39, 35.1%). There was no mortality. Early major cardiac complications occurred in six patients (5.5%) with device embolisation being the commonest (n = 4, 3.7%). The median follow-up period was 19 months (range: 1-84 months) in 89 (81.7%) of the patients. One patient (0.9%) required a permanent pacemaker for a complete heart block. CONCLUSION: This study has demonstrated a good rate of VSD closure with low morbidity and no mortality using the percutaneous approach with different devices. Long-term follow-up is needed to specifically evaluate the function of adjacent structures and the long-term effects on conduction systems.

Phenotypic spectrum of ALPK3-related cardiomyopathy.

Cardiomyopathies are clinically heterogeneous disorders and are the leading cause of cardiovascular morbidity and mortality. Different etiologies have a significant impact on prognosis. Recently, novel biallelic loss-of-function pathogenic variants in alpha-kinase 3 (ALPK3) were implicated in causing early-onset pediatric cardiomyopathy (cardiomyopathy, familial hypertrophic 27; OMIM 618052). To date, eight patients, all presented during early childhood, were reported with biallelic ALPK3 pathogenic variants. We describe the molecular and clinical phenotype characterization of familial cardiomyopathy on one family with six affected individuals. We identified homozygosity for an ALPK3 deleterious sequence variant (NM_020778.4:c.639G>A:p.Trp213*) in all the affected individuals. They presented with either dilated cardiomyopathy that progressed to hypertrophic cardiomyopathy (HCM) or HCM with left ventricular noncompaction. The age of presentation in our cohort extends between infancy to the fourth decade. The phenotypic severity decreases with the progression of age.

Transcatheter Closure of Ruptured Sinus of Valsalva Aneurysm: Report of two cases.

A ruptured sinus of Valsalva aneurysm (RSVA) is a rare cardiac anomaly. Traditionally, RSVAs were repaired surgically; however, percutaneous transcatheter closure is the current treatment of choice. We report two cases of RSVA which were closed using this approach. The first case was a 45-year-old female who presented to the Royal Hospital, Muscat, Oman, in 2014 with a RSVA in the right ventricle. The second case was a 39-year-old male who was admitted to the Sultan Qaboos University Hospital, Muscat, in 2015 with a large multifenestrated RSVA extending into the right ventricle outflow tract. Each patient underwent transcutaneous cardiac catheterisation using three-dimensional echocardiography. Both interventions were technically successful; however, the second patient required a subsequent surgery due to the continuing presence of a significant shunt. Transcatheter closure of RSVAs is an effective alternative to surgical repair, although large multifenestrated RSVAs should be repaired surgically to ensure complete closure.

Percutaneous closure of complex paravalvular aortic root pseudoaneurysm and aorta-cavitary fistulas.

Native aortic valve or its prosthetic valve endocarditis can extend to the adjacent periannular areas and erode into nearby cardiac chambers, leading to pseudoaneurysm and aorta-cavitary fistulas respectively. The later usually leads to acute cardiac failure and hemodynamic instability requiring an urgent surgical intervention. However rarely this might pass unnoticed and the patient might present later with cardiac murmur. Percutaneous device closure of aortic pseudoaneurysm, ruptured sinus of Valsalva aneurysm, aorta-pulmonary window, paravalvular leaks, and aorta-cavitary fistula have been reported. We present a 59-year-old female who developed a large aortic root pseudoaneurysm with biventricular communication aorta-cavitary fistulas presenting late following aortic prosthetic valve endocarditis. She underwent successful percutaneous device closure of her pseudoaneurysm and aorta-cavitary fistulas using two Amplatzer Duct Occluders. This case illustrates a challenging combination of aortic root pseudoaneurysm and biventricular aorta-cavitary fistulas that was successfully treated with percutaneous procedure.

Atrial fibrillation with wide QRS tachycardia and undiagnosed Wolff-Parkinson-White syndrome: diagnostic and therapeutic dilemmas in a pediatric patient.

A 10-year-old girl presented to the emergency department of a regional hospital with 1 episode of generalized tonic-clonic seizures. Postictal monitoring followed by a 12-lead electrocardiogram showed fast atrial fibrillation with intermittent wide QRS regular tachycardia. Immediately following this, her rhythm changed to wide QRS irregular tachycardia without hemodynamic compromise. She was suspected to have ventricular tachycardia and was treated with intravenous amiodarone with cardioversion to sinus rhythm. Subsequent electrocardiogram in sinus rhythm showed typical features of manifest Wolff-Parkinson-White (WPW) accessory pathway. This case illustrates the diagnostic and therapeutic dilemmas in patients with atrial fibrillation, wide QRS tachycardia, and undiagnosed WPW syndrome with antidromic conduction of atrial arrhythmias through the accessory pathway. Furthermore, this case demonstrates that undiagnosed wide QRS tachycardias need to be treated with drugs acting on the accessory pathway, thus keeping in mind underlying WPW syndrome as a possibility to avoid potentially catastrophic events.

Accessory mitral valve tissue causing severe left ventricular outflow tract obstruction in a post-Senning patient with transposition of the great arteries.

Accessory mitral valve tissue is a rare congenital anomaly associated with congenital cardiac defects and is usually detected in the first decade of life. We describe the case of an 18-year old post-Senning asymptomatic patient who was found to have accessory mitral valve tissue on transthoracic echocardiography producing severe left ventricular outflow tract obstruction.