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Published on: August 6, 2019
Conventional versus modified delivery system technique in commissural alignment from the Evolut low-risk CT substudy
Gilbert H L Tang1, Aditya Sengupta1, Sophia L Alexis1
1Department of Cardiovascular Surgery and Cardiology, Mount Sinai Hospital, New York, New York, USA.
Objectives:
We assessed the impact of conventional delivery system (DS) insertion technique on "Hat-marker" orientation/commissural alignment in patients who underwent transcatheter aortic valve replacement (TAVR) in the Evolut Low Risk Trial CT substudy versus a modified technique.
Background:
Unlike surgical aortic valve replacement, where alignment of the surgical valve commissures with native commissures can be achieved virtually 100% of the time, commissural alignment during TAVR is not achieved consistently. This may subsequently impact the feasibility of both coronary access and reintervention after TAVR.
Methods:
"Hat-marker" orientations during deployment were characterized as outer curve (OC), center front (CF), inner curve, and center back. Severe commissure-to-CA overlap was 0-20°. "Hat-marker" orientations and CA overlap were compared to 240 patients from a single center using the modified 3-o'clock flush port DS technique.
Results:
In the CT substudy in which conventional DS insertion was performed (flush port at 12 o'clock); 154/249 had both analyzable CT and procedural fluoroscopy to validate "Hat-marker" to C-tab/commissural orientation. On post-TAVR CT, Evolut valve commissural orientation and coronary artery (CA) ostia were identified. Compared to conventional DS technique in the CT substudy, the modified technique had higher rates of "Hat-marker" at OC/CF orientation, improved commissural alignment and reduced severe CA overlap; (left main, 14.2 vs. 27.9%; right coronary artery, 11.7 vs. 27.3% both, 5.0 vs. 13.6%; 1 or both CA, 20.8 vs. 41.6%, all p < 0.01).
Conclusions:
The modified technique improved initial "Hat-marker" orientation during Evolut deployment and resulted in better commissural alignment and reduced CA overlap.
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