麻豆传媒

Registry data suggested that valve leaflet laceration helped protect patients at risk of coronary artery obstruction during transcatheter aortic valve replacement (TAVR).

Safety of the electrosurgical technique, known as Bioprosthetic or native Aortic Scallop Intentional Laceration to prevent Iatrogenic Coronary Artery obstruction (BASILICA), was reflected in the 3.4% rate of death or disabling stroke at 30 days among 214 patients.

Incidence was 2.8% for mortality, 2.8% for stroke, and 0.5% for disabling stroke, according to Ron Waksman, MD, of MedStar Washington Hospital Center, D.C., and colleagues, .

"This is comparable to outcomes in patients undergoing TAVR who are not specifically at risk of coronary artery obstruction," the authors noted in their manuscript, presented simultaneously during the virtual Cardiovascular Research Technologies conference on Saturday.

BASILICA performed immediately before TAVR was associated with 86.9% procedural success, defined by successful traversal and laceration without mortality, coronary obstruction, or emergency intervention.

"These data should be reassuring and should facilitate wider dissemination of the BASILICA procedure at high-volume centers," Waksman's group concluded.

However, partial or complete coronary obstruction was observed in 4.7% of patients despite BASILICA (six partial cases, four complete). One person who had complete obstruction had a second valve deployed without obstruction, only to die subsequently during the inpatient stay.

That rate of obstruction was "concerning," as was the lower procedural success rate (80%) in double-leaflet BASILICA, commented Danny Dvir, MD, of Shaare Zedek Medical Center in Jerusalem, who was not involved with the study.

"In addition, we do know that many centres still prefer to do the chimney/snorkel technique in which a stent is deployed in the coronary ostium in order to prevent coronary obstruction. The reason why the stent technique is much more common worldwide is that it is easier to deploy a stent than to do BASILICA," he told 麻豆传媒 in an email.

Dvir suggested that a dedicated tool for leaflet laceration, such as Pi-Cardia's ShortCut investigational device -- with its first-in-human procedures performed and -- may allow for better dissemination of this technique to more centers.

Study authors performed a retrospective analysis of the International BASILICA Registry's 214 patients (68.7% women, mean age 74.9 years) enrolled at 25 centers in North America and Europe.

BASILICA was performed on failed bioprosthetic valves in 72.8% of cases and the rest in native aortic valves. One valve cusp was targeted in 78.5% of patients, the rest having two cusps targeted. Operators used Sentinel embolic protection in 47.7% of cases.

Leaflet traversal was successful in 94.9% of patients, with leaflet laceration successful in 94.4%, according to Waksman's team.

Procedural complications during BASILICA TAVR included one mitral chord laceration requiring mitral valve replacement 2 months later, three inadvertent traversals into the interventricular septum and one through the aortic root, and hypotension requiring pressors in 8.5% of cases.

The VARC-2 composite safety endpoint was reached by 82.8% of the group at 30 days. One-year survival was 83.9% in the 124 individuals with sufficient follow-up.

Study findings mark an improvement over the 30-person early feasibility study of BASILICA that showed successful leaflet traversal and laceration in 93% but one death and one major stroke in the same patient by 30 days, plus two non-disabling strokes.

Waksman and colleagues credited some of their success in BASILICA with the consistent use of a 5% dextrose flush during laceration.

"Five percent dextrose is non-ionic, and therefore, concentrates charge on the leaflet to promote efficient laceration. Perhaps more important, the dextrose infusion displaces blood that would coagulate if heated with electrosurgery current through the guidewire, which could lead to thrombosis and debris embolization," according to them.

"Moreover, dextrose infusion improves electrosurgical laceration efficiency and may, thereby, reduce the incidence of mechanical avulsion causing cerebral and coronary embolization," they added.

The investigators cautioned that registry data were site-reported without independent monitoring and data verification.

Comparing BASILICA with the alternative stent technique will also be important moving forward, according to Dvir.

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