麻豆传媒

Refined technique and pre-procedural planning for transcatheter correction of sinus venosus atrial septal defects (SVASDs) yielded consistently good outcomes at one center.

The procedure redirects the superior vena cava (SVC) and right upper pulmonary vein flow to the right and left atria, respectively, by implantation of a covered stent in the SVC.

None of the 25 adults who underwent the transcatheter procedure died over a median 1.4 years of follow-up, according to Eric Rosenthal, MD, of Evelina London Children's Hospital, and colleagues reporting in the March 24 issue of the.

Two serious adverse events were noted: one patient had a stent embolization within hours, and another required surgical drainage of hemopericardium that had developed days after the procedure.

Surgery is the standard of care for SVASD correction and was the only treatment until one group reported the use of the novel transcatheter approach in 2013.

Now, Rosenthal's team has made transcatheter correction of SVASD, and the partial anomalous pulmonary venous drainage (PAPVD) that usually comes with them, a reproducible procedure at their institution by using comprehensive pre-procedure planning (with advanced segmentation of cross-sectional imaging and 3D reconstruction) and refinements in procedural techniques.

"Transcatheter treatment of SVASDs is an attractive alternative to surgical treatment," they said. "Based on our single-center experience, approximately 75% of patients with an SVASD and PAPVD may be suitable for transcatheter correction. Medium-term results are promising, but longer follow-up studies are warranted."

The paper showed 48 consecutive adult patients accepted for treatment in 2016-2019, of whom 83% had suitable anatomy for a transcatheter approach.

Out of the overall cohort, 25 underwent the transcatheter procedure; six were still waiting for stent implantation at the time of the report; and 17 were referred for surgery due to unsuitable anatomy, need for concomitant procedures, or patient or physician preference.

Median age was 46 years among the 25 patients who got transcatheter SVASD and PAPVD correction.

Follow-up cardiac CT in 22 patients confirmed unobstructed pulmonary venous return at 3 months. The 14 people who underwent cardiac MRI at 1 year showed a significant reduction of indexed right ventricular end-diastolic volume.

"A small residual shunt was noted on [transesophageal echocardiography] in more than one-half of the patients at the end of the procedure. We anticipated that after the stent had endothelialized and volume unloading led to a reduction of RA size, the shunt would resolve," according to Rosenthal and colleagues.

Only one patient had a residual shunt at late follow-up. This person had had a small residual gap at the inferior margin of the stent at the end of SVASD correction, they reported.

"As with the surgical approach to the correction of SVASD, the possibility of sinus node dysfunction is a potential concern when a stent is implanted in the SVC and right atrial junction. There has been no short- to medium-term evidence on serial electrocardiograms of sinus node dysfunction in any of the patients during follow-up," Rosenthal's group wrote.

They noted that they initially assessed for suitability using 3D-printed models and ex vivo stent implantation. More recently, they moved toward just simulating the procedure in a virtual 3D model or using high-quality 3D CT scans.

The transcatheter procedure should be considered still "only in its infancy" given the longest follow-up of 3.8 years, Rosenthal's group cautioned.

"Although the experience is limited, the results are encouraging and worthy of further application," according to an accompanying editorial from a trio led by Lee Benson, MD, of Toronto General Hospital and University of Toronto School of Medicine, Ontario.

Rosenthal's report underscored how innovative device application and careful assessment of lesion morphology have become invaluable in procedural preparation in the management of complex congenital heart lesions, Benson's group said.

"This approach has enabled safe applications of advanced technologies, improving patient safety and increasing procedural success, not only in the interventional arena but in surgical applications as well," according to the editorialists. "Practice makes perfect!"

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