Modified Technique to Create Diabolo Stent Configuration

Use of Flow Restrictors in Congenital Heart Disease

The surgical pulmonary artery band was first introduced in 1952 and, to this day, can produce challenges in regard to the ideal amount of restriction and the need for reoperations. A transcatheter option may be the ideal solution as it allows for a less-invasive approach for a better hemodynamic assessment and easier re-intervention. To date, multiple approaches have been developed with device modifications to create restrictions to flow, each with advantages and limitations. Continued experience is still necessary to determine the ideal device to use to create an adequate and modifiable level of restriction.

Novel application of the Diabolo technique to restrict pulmonary blood flow in a single ventricle patient with a right ventricle to pulmonary artery conduit

Balancing pulmonary and systemic circulations in single ventricle patients with a conduit after Stage 1 palliation is challenging. A transcatheter intervention for excessive pulmonary blood flow would provide benefit. We report a case of a critically ill single ventricle patient with symptoms of excessive pulmonary blood flow after Stage 1 despite maximal medical therapy. The patient underwent percutaneous intraluminal downsizing of the right ventricle to pulmonary artery conduit using a novel application of the Diabolo-covered stent technique, with subsequent clinical improvement. A second catheterization was performed during the interstage period with successful dilation of the stent to achieve appropriate saturations. The Diabolo technique can be successfully employed in this population to restrict pulmonary blood flow and has the advantage of being adjusted during placement and in subsequent interventions.

Extra-cardiac and complex Fontan baffle fenestration using radio frequency current via surgical electrocautery

BACKGROUND

Fontan baffle punctures and creation of Fontan fenestration for cardiac catheterisation procedures remain challenging especially due to the heavy calcification of prosthetic material and complex anatomy.

OBJECTIVES

We sought to evaluate our experience using radiofrequency current via surgical electrocautery needle for Fontan baffle puncture to facilitate diagnostic, electrophysiology, and interventional procedures.

METHODS

A retrospective chart review of all Fontan patients (pts) who underwent Fontan baffle puncture using radiofrequency energy via surgical electrocautery from three centres were performed from January 2011 to July 2021.

RESULTS

A total of 19 pts underwent 22 successful Fontan baffle puncture. The median age and weight were 17 (3-36 years) and 55 (14-88) kg, respectively. The procedural indications for Fontan fenestration creation included: diagnostic study (n = 1), atrial septostomy and stenting (n = 1), electrophysiology study and ablation procedures (n = 8), Fontan baffle stenting for Fontan failure including protein-losing enteropathy (n = 7), and occlusion of veno-venous collaterals (n = 2) for cyanosis. The type of Fontan baffles included: extra-cardiac conduits (n = 12), lateral tunnel (n = 5), classic atrio-pulmonary connection (n = 1), and intra-cardiac baffle (n = 1). A Fontan baffle puncture was initially attempted using traditional method in 6 pts and Baylis radiofrequency trans-septal system in 2 pts unsuccessfully. In all pts, Fontan baffle puncture using radiofrequency energy via electrocautery needle was successful. The radiofrequency energy utilised was (10-50 W) and required 1-5 attempts for 2-5 seconds. There were no vascular or neurological complications.

CONCLUSIONS

Radiofrequency current delivery using surgical electrocautery facilitates Fontan baffle puncture in patients with complex and calcified Fontan baffles for diagnostic, interventional, and electrophysiology procedures.

Transcatheter Interventions for Neonates with Congenital Heart Disease: A Review

Newborns with congenital heart disease often require interventions linked to high morbidity and mortality rates. In the last few decades, many transcatheter interventions have become the first-line treatments for some critical conditions in the neonatal period. A catheter-based approach provides several advantages in terms of procedural time, length of hospitalization, repeatability and neurodevelopmental issues (usually related to cardiopulmonary bypass). The main transcatheter procedures will be reviewed, as they are now valid alternatives to conventional surgical management.

Novel Diabolo Configuration of a Large Covered Stent to Treat Cyanosis Related to Pulmonary Arteriovenous Malformations

Microvascular pulmonary arteriovenous malformations (pAVMs) can lead to profound hypoxemia. "Hepatic factor" is postulated to play a role in their development. Certain patients with congenital heart disease are at particular risk to develop pAVMs, including those with heterotaxy syndromes and complex Fontan palliation. Ideally, an underlying cause is identified and corrected, although pAVMs may persist despite those interventions. We report a patient with heterotaxy syndrome s/p Fontan who had pAVMs that persisted despite Fontan revision with equal hepatic flow to both lungs. We employed a novel method to produce a diabolo configuration of a large covered stent to restrict lung flow while maintaining the potential for future dilation.

Transcatheter Cardiac Interventions in the Newborn: JACC Focus Seminar

For neonates with critical congenital heart disease requiring intervention, transcatheter approaches for many conditions have been established over the past decades. These interventions may serve to stabilize or palliate to surgical next steps or effectively primarily treat the condition. Many transcatheter interventions have evidence-based records of effectiveness and safety, which have led to widespread acceptance as first-line therapies. Other techniques continue to innovatively push the envelope and challenge the optimal strategies for high-risk neonates with right ventricular outflow tract obstruction or ductal-dependent pulmonary blood flow. In this review, the most commonly performed neonatal transcatheter interventions will be described to illustrate the current state of the field and highlight areas of future opportunity.

Impact on clinical outcomes from transcatheter closure of the Fontan fenestration: A systematic review and meta-analysis

BACKGROUND

Meta-analysis of the impact on clinical outcome from transcatheter closure of Fontan fenestration.

METHODS

Cochrane, Embase, MEDLINE, and Open-Gray were searched. Parameters such as changes in oxygen saturation, cavo-pulmonary pressure, maximum heart rate during exercise, exercise duration, and oxygen saturation after fenestration closure were pooled and statistical analysis performed.

RESULTS

Among 922 publications, 12 retrospective observational studies were included. The included studies involved 610 patients, of which 552 patients (90.5%) had a fenestration. Of those patients, 505 patients (91.5%) underwent attempt at trans-catheter closure. When it could be estimated, the pooled overall mean age at trans-catheter fenestration closure was 6.6 ± 7.4 years, and the mean follow-up time was 34.4 ± 10.7 months. There were 32 minor (6.3%) and 20 major (4.0%) complications during or after trans-catheter Fontan fenestration closure. The forest plots demonstrate that following fenestration closure, there was a significant increase in the mean arterial oxygen saturation of 7.9% (95% CI 6.4-9.4%, p < 0.01). There was also a significant increase in the mean cavo-pulmonary pressure of 1.4 mmHg (95% CI 1.0-1.8 mmHg, p < 0.01) following fenestration closure. The exercise parameters reported in 3 studies also favored closing the fenestration as well, yet the exercise duration increase of 1.7 min (95% CI 0.7-2.8 min, p < 0.01) after fenestration closure is probably clinically insignificant.

CONCLUSION

Late closure of a Fontan fenestration has the impact of improving resting oxygen saturation, exercise oxygen saturation, and a modest improvement of exercise duration. These clinical benefits, however, may be at the expense of tolerating slightly higher cavo-pulmonary mean pressures.