A novel technique for stenting pulmonary artery and conduit bifurcation stenosis

Percutaneous approach to residual pulmonary bifurcation stenosis in conotruncal diseases

Residual stenosis after right ventricle outflow tract surgery represents a major issue to manage in the children and adult patient with conotruncal defects. Despite a detailed multimodality imaging, the anatomy of distal pulmonary trunk and pulmonary artery bifurcation may be challenging in these patients.The aim of this study was to analyse retrospectively the outcome of the percutaneous transcatheter treatment in children with post-surgical stenosis of pulmonary artery bifurcation.We enrolled 39 patients with a median age of 6.0 years. Standard high-pressure balloon dilation was attempted in 33 patients, effective in 5 of them. Pulmonary branch stenting was performed in 10 patients, effective in 6. A kissing balloon approach was chosen in 17 patients (6 after angioplasty or stenting failure), and this technique was effective in 16 cases. Finally, a bifurcation stenting was performed in 10 patients (second step in 9 cases), effective in all the cases. None of the patients approached by kissing balloon needed a bifurcation stenting.In conclusion, standard balloon angioplasty and standard stenting might be ineffective in post-surgical stenosis involving pulmonary artery bifurcation. In this population, kissing balloon or bifurcation stenting, followed by side branch de-jailing, may be more effective in relieving the gradient.

First in man study of a new semi-open cell design Zephyr cobalt-chromium stent in large vessels and conduits

OBJECTIVES

We present a first-in-man clinical use of a new hybrid design stent in stenosed large vessels. Its unique C and S polylinks prevent foreshortening without compromising its strength. Its thin profile permits use of smaller introducer sheaths.

BACKGROUND

Stent angioplasty is widely employed in large vessel and conduit stenosis. These procedures are associated with difficulties due to large stent profiles, stent fractures, foreshortening and recoil. Cobalt chromium stents have high tensile strengths compared to stainless steel stents.

METHODS

A retrospective analysis of feasibility and safety of a new Cobalt chromium stent in large vessels namely aorta, pulmonary arteries and outflow conduits was done from two institutions. Demographic patient details, procedural results, complications and medium term follow-up were analyzed. Stent recoil, foreshortening, fractures were assessed.

RESULTS

Twenty patients including three with aortic coarctations, seven with stenosed conduits and 10 with pulmonary artery stenosis underwent stent angioplasty using 23 stents. Three stents were deployed to expand further a previously implanted stent. Procedure was successful in all patients, lumen increased by 150-300%, gradients reduced in all patients. There was no stent recoil, foreshortening or fractures. There were no complications. At a follow up of 3-27 months, there were no stent related complications and the gradients remained stable.

CONCLUSIONS

The new Zephyr stent was useful in a wide variety of stenotic lesions involving large vessels including those that were previously stented. Lack of stent recoil and foreshortening seems to be an advantage for this new stent that needs validation in larger multicenter studies.

Modified Stumper technique for acute postoperative bifurcation stenosis causing right ventricular failure after Ross procedure

In this report, we describe a 15-year-old patient who underwent a Ross procedure for a regurgitant bicuspid aortic valve and ascending aortic dilation. After the operation was over, he could not be separated from cardiopulmonary bypass and was noted to have isolated right ventricular failure. This report takes the reader through the diagnostic evaluation, highlights the importance of invasive assessment in the immediate postoperative period, and discusses successful transcatheter intervention in the acute postoperative setting.

Bifurcating stents in the pulmonary arteries: A novel technique to relieve bilateral branch pulmonary artery obstruction

Balloon angioplasty and stent placement in close proximity to the bifurcation of the branch pulmonary arteries can be challenging. Multiple approaches have been previously described, though none of these approaches both treats bilateral proximal branch pulmonary artery stenosis and provides an anchor for a transcatheter pulmonary valve replacement. We report a novel approach that involves serial stent placement and balloon dilation through the struts of the stent in each pulmonary artery, along with balloon expansion of the proximal portion of the stents to the diameter of the main pulmonary artery. In the two cases we describe, this strategy resulted in significant relief of branch pulmonary artery obstruction without compromising the anatomy of the main pulmonary artery segment. This technique can be an effective way to alleviate stenoses of the bilateral proximal branch pulmonary arteries and provides a landing zone for a future transcatheter pulmonary valve.

Extended Szabo (anchor-wire) technique concept for stent implantation in congenital heart lesions

We report the usefulness of the Szabo (anchor-wire) technique and two modifications of such based on the same concept for stent implantation in congenital heart lesions. The modifications of the original technique are related to the localization of the cell of the stent through which the anchor wire, which stops the stent advancement, is introduced: proximal in the original technique and central or distal in the reported modifications. These techniques were performed in six patients: in two to maintain permeability of the ductus arteriosus, in three to achieve a fenestration of the interatrial septum, and in one to implant a stent in a right ventricle-to-pulmonary artery conduit close to the bifurcation. We describe the technique as well as the most important difficulties and complications encountered. The Szabo or anchor-wire technique concept is a new tool for stent implantation that can provide more accurate stent positioning compared with conventional angiographically guided implantation in different congenital heart defects. As with any new tool, this technique demands a learning curve and knowledge of potential complications.