Therapeutic drug monitoring of flecainide in children using plasma concentration measurements is undertaken by some clinicians. There is very little published evidence surrounding factors which influence plasma flecainide concentration, particularly in paediatric populations. We undertook a retrospective study of 45 children receiving flecainide to identify factors that influence its plasma concentration. Patients receiving a dose of 6 mg/kg/day had a higher mean plasma flecainide concentration than those receiving lower doses. Younger age and lighter weight were also associated with higher plasma flecainide concentrations. Children aged younger than 1 year receiving flecainide three times a day had a higher mean plasma flecainide concentration than older children who received flecainide twice a day. All supratherapeutic levels occurred in children aged less than 1 year who were receiving flecainide three times a day. Supratherapeutic levels were more common in those receiving 6 mg/kg/day while subtherapeutic levels were more common in those receiving 2 mg/kg/day. A supratherapeutic level did not correlate with adverse effects or clinical toxicity. Our results would suggest the need for a change of practice from prescribing flecainide at a frequency of three times a day in children aged younger than 1 year to twice a day in line with other ages.

Prolonged pleural effusion is a fairly common condition which has considerable impact on complicated and longer hospital stays after Fontan surgery. Identifying the patient population prone to have pleural effusions is still seeking for an answer. This study is to determine the variables that may predict prolonged pleural effusion according to the data of 69 patients who underwent Fontan operation between June 2018 and December 2020 and survived to date. Prolonged pleural effusion was defined as the need for a chest tube for more than 7 days. Two patient groups, with and without prolonged effusion, were compared in terms of pre-, peri-, and post-operative variables. The patients were subdivided into "high-risk" and "low-risk" groups based on the pre-operative catheterisation data. The most frequent main diagnosis was tricuspid atresia (n: 13, 19%). Among 69 patients, 28 (40%) had prolonged pleural effusion whereas 11 (16%) had effusions that lasted longer than 14 days. Ten patients among prolonged effusion group (35%) had pulmonary atresia coexistent with the main diagnosis. Fontan operation was performed in 6 patients (8.7%) over the age of 10, and 4 of these patients (67%) had prolonged pleural effusion. Among numerous variables, statistical significance between the two groups was achieved in pre-operative mean pulmonary artery pressure, post-operative albumin, C-reactive protein levels, length of hospital stay, duration of chest tube drainage, and amount of effusion per day. Early recognition and treatment strategies with routine medical protocol use remain to be the cornerstone for the management of post-operative prolonged pleural effusions after Fontan surgery.

We present two exceptional cases of 14-year-old girls diagnosed with rare cardiomyopathies (left ventricular non-compaction, and arrhythmogenic right ventricular cardiomyopathy), both presenting with the unusual finding of bidirectional ventricular tachycardia.

We report two cases of successful emergency pacing via the umbilical vein in neonates with congenital complete atrioventricular block. The first patient, a neonate with normal cardiac anatomy, underwent emergency temporary pacing via the umbilical vein under echocardiographic guidance. The patient underwent permanent pacemaker implantation on postnatal day 4. The second patient, a neonate with heterotaxy syndrome, underwent emergency temporary pacing through the umbilical vein under fluoroscopic guidance. The patient underwent permanent pacemaker implantation on postnatal day 17.

A 14-year-old previously healthy female presented with chest pain and dyspnoea for 2 days in the setting of a recent upper respiratory infection. She had elevated inflammatory markers and troponin, resulting in the diagnosis of acute myocarditis. Transthoracic echocardiography demonstrated mild systolic dysfunction and a moderate pericardial effusion. Additionally, her echocardiogram showed concentric left ventricular hypertrophy raising concern for hypertrophic cardiomyopathy. She was treated with intravenous immunoglobulin. Serial echocardiograms revealed rapid resolution of her ventricular hypertrophy. Cardiac magnetic resonance confirmed the diagnosis of myocarditis.

Device-induced aortic obstruction is a known rare complication following transcatheter closure of patent ductus arteriosus in extremely low-birth-weight infants. Various mechanisms have been proposed. We report the first description of late aortic obstruction due to ductal vasoconstriction on pulmonic end causing device to be gradually pushed out of aortic end in a 980-gram premature infant.

Therapeutic options are limited for the management of extremely low-birth-weight infants with critical aortic coarctation despite high doses of prostaglandin infusion. We report successful hybrid, fluoroscopy-free, echocardiography-guided primary stenting of native aortic coarctation in a 920-grams premature infant.

Enlarged coronary sinus detected during cardiac examination in the prenatal period is the first finding that raises suspicion for persistent left superior vena cava. In this report, a patient was presented who was referred with the prediagnosis of cor triatriatum sinister in the antenatal period and diagnosed with isolated persistent left superior vena cava (SVC).

A neonate was seen for an evolving broad QRS complex rhythm initially captured at birth as intermittent escape beats on electrocardiogram. Continuous monitoring recorded features mimicking pre-excitation, but closer analysis revealed a regular broad QRS complex rhythm with isorhythmic atrioventricular dissociation, favouring a ventricular source. Treatment with flecainide and propranolol achieved successful control of the incessant arrhythmia with improvement in cardiac function on echocardiogram.

Aortic pseudoaneurysm is a rare, life-threatening complication that can occur after cardiac surgery, trauma, or infections. Surgical repair of aortic pseudoaneurysm is the conventional treatment, but it is associated with very high morbidity and mortality especially in early post-operative period. However, very limited reports of successful transcatheter repair of aortic pseudoaneurysm related to surgery appear in the literature. Herein, a case of a 9-year-old female who developed a pseudoaneurysm, after aortic reconstruction, that was successfully treated percutaneously using atrial septal occluder is presented.

Transposition of the great arteries with left ventricle outflow tract obstruction in combination with situs inversus totalis and dextrocardia is a very rare anomaly and carries high morbidity and mortality. Only few cases have been reported with this anomaly. We describe a 21-day of infant girl with transposition of the great arteries and mirror image dextrocardia and pulmonary stenosis who underwent successful neonatal arterial switch operation and left ventricle outflow tract obstruction resection following PDA stent implantation

Infantile hemangiomatosis is among the most common vascular tumours of childhood that is generally accepted as benign. Some cases may have multiple hemangiomas with organ involvement, especially of the liver. This case report will present the clinical and laboratory findings obtained during the treatment and follow-up of a 36-day-old female baby with hemangiomatosis with diffuse liver involvement, high-output heart failure, and pulmonary hypertension.

I read with interest the article by Haddad et al concerning the bench testing of BeSmooth peripheral tests, and I would like to share some thoughts and highlight few points.

BeSmooth stent is behaving like any pre-mounted stent available on the market. None can achieve the Holy Grail of being dilatable to adult size without losing their integrity. Until dedicated stents are available, pre-mounted stents are preferred to unmounted stents because of their better profile and deliverability. Technically, proper post-dilatation should be performed in order to avoid and extensive foreshortening and the formation of a ring that would limit further expansion of the stent. BeSmooth stent like other pre-mounted stents can also be used without restriction in situations where overexpansion is not required.

BeSmooth stent platform with the knowledge of its intrinsic properties is, in our opinion, a good add-on to the armamentarium of pre-mounted stents used in paediatric cardiology.