Percutaneous intraluminal downsizing of systemic-to-pulmonary artery shunts: a novel application of the Diabolo stent technique-Case series and description of the technique.

Objective: This article aims to describe the feasibility of a novel application of the Diabolo stent technique for percutaneous downsizing of systemic-to-pulmonary artery shunts in patients with pulmonary overcirculation.

Background: Pulmonary overcirculation can lead to systemic hypoperfusion, impaired systemic oxygen delivery, and hemodynamic instability especially in patients with single-ventricle physiology. Different medical and surgical strategies to treat pulmonary overcirculation have been reported so far, but no percutaneous approach amenable to further adjustment over time has been described.

Methods: Retrospective review of patients who underwent percutaneous intraluminal reduction of a systemic-to-pulmonary artery shunt with a covered stent in a Diabolo "hour-glass" configuration.

Results: From July 2018 to February 4, 2019, consecutive patients underwent trans-catheter downsizing of a systemic-to-pulmonary artery shunt. The median age was 3.3 years (range 0.7-5.7 years). All patients had symptomatic pulmonary overflow despite maximal medical therapy. All patients underwent successful implantation of a covered stent in a Diabolo "hour-glass" configuration without any complications. Successful reduction in pulmonary overcirculation was noted in all patients with a decrease of mean pulmonary artery pressure from a median of 29 mmHg (range 25-32 mmHg) to a median of 21 mmHg (range 14-27 mmHg).

Conclusions: Percutaneous intraluminal downsizing of systemic-to-pulmonary artery shunts with a covered stent in a Diabolo configuration is safe and feasible. With this technique, the pulmonary blood flow can be adjusted in a physiologic closed-chest condition and further regulated over time.