Pulmonary arteriovenous malformations in single ventricle congenital heart disease are poorly understood. Previous studies investigating pulmonary arteriovenous malformations predominantly focus on patients with heterotaxy syndrome and interrupted inferior caval vein. It is unknown if development and resolution of pulmonary arteriovenous malformations are similar for patients with and without heterotaxy syndrome.

In this retrospective single-institution study, we identified patients with a history of single ventricle congenital heart disease and Fontan palliation. We then matched patients with heterotaxy syndrome (intact and interrupted inferior caval vein) and non-heterotaxy hypoplastic left heart syndrome. To compare development of pulmonary arteriovenous malformations, we identified the frequency of positive diagnoses pre-Fontan. To compare resolution of pulmonary arteriovenous malformations, we recorded oxygen saturation changes for 12 months following Fontan.

A total of 124 patients were included. Patients with heterotaxy and interrupted inferior caval vein were more likely to have a pre-Fontan contrast echocardiogram performed (p < 0.01) and more likely to be diagnosed with pulmonary arteriovenous malformations pre-Fontan (p < 0.01). There was no difference in oxygen saturation prior to Fontan, yet all patient groups had increased their oxygen saturations in the first year after Fontan discharge.

Pulmonary arteriovenous malformations are variably diagnosed prior to Fontan palliation; however, all study groups had increased oxygen saturations after Fontan discharge, potentially indicating resolution of pulmonary arteriovenous malformations in all groups. The prevalence of pulmonary arteriovenous malformations pre-Fontan is likely underestimated. A quantitative, systematic approach to diagnosis and follow-up of pulmonary arteriovenous malformations is needed to better understand susceptibility and pathophysiology.

Despite patent ductus arteriosus closure in premature infants is a relatively fast procedure, it involves specific steps for equipment exchange and the use of a 4-Fr catheter, which may be large for tiny infants, potentially causing haemodynamic instability or tricuspid valve regurgitation.

This study aims to describe the early experience with a new technique designed to simplify transcatheter patent ductus arteriosus closure in premature infants. It enables the closure using the KA micro plug device via a single microcatheter without equipment exchanges and contrast exposure. This technique involves a simple modification of the microcatheter by creating a curved tip.

This is a retrospective, single-institution study involving premature infants who underwent attempted transcatheter patent ductus arteriosus closure using a manually modified microcatheter of the KA micro plug device at Stead Family Children’s Hospital.

Five patients underwent transcatheter patent ductus arteriosus closure using a KA micro plug with a modified microcatheter. The procedure was successful in all patients, with no haemodynamic instability. The median (range) for procedural weight, time, and radiation dose were 1055 g (730–1330), 12 minutes (11–19), and 0.49 µGy.m2 (0.14–1), respectively. At a median follow-up of 1.1 months (0.17–2.6), all patients maintained good device position without residual shunt or other concerning echocardiogram findings.

Transcatheter patent ductus arteriosus closure in infants weighing less than 1500 g can be successfully performed using a KA micro plug device through a microcatheter with zero-contrast use, low radiation exposure, and a short procedure time.

Thoracic endovascular aneurysm repair has been employed to treat late complications after aortic coarctation correction. However, its use in children has seldomly been reported.

We present the case of a 15-year-old child who presented with a ruptured aneurysm of the descending aorta complicated later by an aortic-oesophageal fistula following aortic coarctation stenting that was managed with multiple bridging endovascular interventions until a definitive repair was performed.

Thoracic endovascular aneurysm repair may be used successfully as a bridging intervention to a definitive repair in children with life-threatening aortic complications following aortic coarctation repair.

To evaluate the results of balloon dilatation of stenotic homografts in children, adolescents, and young adults and to identify factors that might influence or predict the effect of the dilatation.

Homografts are widely used in congenital cardiac surgery; however, the longevity remains a problem mostly because of stenosis in the homograft. The effect of treatment by balloon dilatation is unclear.

In a retrospective study, the effect of balloon dilatation was determined by the percentage of reduction of the peak systolic pressure gradient over the homograft during catheterisation and the postponement of re-intervention or replacement of the homograft in months. Successful dilatations – defined in this study as a reduction of more than 33% and postponement of more than 18 months – were compared with unsuccessful dilatations in search of factors influencing or predicting the results.

The mean reduction of the peak systolic pressure gradient was 30% in 40 procedures. Re-intervention or replacement of the homograft was postponed by a mean of 19 months. In all, 14 balloon dilatations (35%) were successful; the mean reduction was 49% and the mean postponement was 34 months. The time since homograft implantation, the presence of calcification, the homograft/balloon ratio, and the pressure applied during dilatation all tended to correlate with outcome, but were not statistically significant.

Balloon dilatation is able to reduce the peak systolic pressure gradient over homografts in a subgroup of patients and can be of clinical significance to postpone re-intervention or pulmonary valve replacement.

Intracardiac echocardiography Doppler-derived gradients have previously been shown to correlate with post-procedure echocardiographic evaluations when compared with invasive gradients measured during percutaneous pulmonary valve implantation, suggesting that intracardiac echocardiography could offer an accurate and predictable starting point to estimate valve function after percutaneous pulmonary valve implantation.

We performed a retrospective chart review of 51 patients who underwent percutaneous pulmonary valve implantation between September 2018 and December 2019 in whom intracardiac echocardiography was performed immediately after valve implantation. We evaluated the correlation between intracardiac echocardiography gradients and post-procedural Doppler-derived gradients. Among the parameters assessed, those which demonstrated the strongest correlation were used to create a predictive model of expected echo-derived gradients after percutaneous pulmonary valve implantation. The equation was validated on the same sample data along with a subsequent cohort of 25 consecutive patients collected between January 2020 and July 2020.

All the assessed correlation models between intracardiac echocardiography evaluation and post-procedure transthoracic echocardiographic assessments were statistically significant, presenting moderate to strong correlations. The strongest relationship was found between intracardiac echocardiography mean gradients and post-procedural transthoracic echocardiographic mean gradients. Therefore, an equation was created based on the intracardiac echocardiography-derived mean gradient, to allow prediction of the post-procedural and follow-up transthoracic echocardiographic-derived mean gradients within a range of ±5 mmHg from the observed value in more than 80% of cases.

There is a strong correlation between intracardiac echocardiography and post-procedure transthoracic echocardiographic. This allowed us to derive a predictive equation that defines the expected transthoracic echocardiographic Doppler-derived gradient following the procedure and at out-patient follow-up after percutaneous pulmonary valve implantation.