460 BIOPROSTHESIS HEMODYNAMICS AND CORONARY FLOW AFTER TAVI IN TAVI
Authors: Motta Silvia Crescenzia , Costa Giuliano , Strazzieri Orazio , Di Pietro Elena , Frittitta Valentina , Barbanti Marco , Tamburino Corrado 
Published: December 2022

Abstract

Background
TAVI-in-TAVI is a complex intervention, potentially associated with feared complications such as coronary artery obstruction or Sinus of Valsalva (SOV)sequestration. Coronary obstruction risk is high when the degenerated bioprosthesis has supra-annular leaflets, the sinus of Valsalva is effaced, and/or sino-tubular Junction (STJ) is narrow.

Clinical Case
A 91 years old man, underwent TAVI with Acurate NEO M in 2016 with good results: post procedural mean gradient was 8mmHg and PVL was mild. He was admitted in our Institute after six years from index procedure for an episode of acute heart failure with echocardiogram findings of prolapse of one of the prosthetic leaflet causing severe aortic regurgitation without signs of active endocarditis. He was a potential candidate for transfemoral TAVI in TAVI and he had an intermediate risk score. The most important phase of this procedure was a careful planning through the preprocedural CTA. The potential maximal neoskirt of the Acurate M is 30mm. In this case, on one hand, we had wide SOV of 33mm of diameter and wide STJ of 30mm of diameter, on the other hand we had a left main ostia height of 15.5mm, a right coronary artery ostia height of 14mm and a STJ height of 25mm from the basal plane of the transcatheter heart valve (THV), hence we excluded THV with higher frame as Evolut or Acurate to prevent the formation of a long-covered stent of at least 23-24mm and 29-30mm respectively. In the trasversal annular plane obtained by multiplanar CT reconstruction we implanted a “virtual” valve at the geometric center simplified as a cylinder with a diameter of 23 mm to measure the valve to coronary (VTC) and valve to sino-tubular junction (VTSTJ) distance obtaining safe values of 5mm and 8mm respectively, both above the high risk threshold of 4mm for VTC and 2,5-3,5mm for VTSTJ. We chose a SAPIEN ULTRA 23mm for its short frame with a potential maximal neoskirt of 18mm and for its open cell strut to facilitate coronaries reaccess at the cost of a higher degree of first THV leaflets overhang. We decided to perform a low implant with more percentage of overhang THV but a low risk of coronaries flow impairment.

Results
Excellent result with correct positioning, coronaries patency and absence of leak. The selective cannulation of both coronaries was performed easily and successfully. The patient was discharged the next day with stable haemoglobin and a mean gradient of 8mmHg with no intraprosthetic aortic regurgitation.

Conclusion
In case of leaflets degeneration with preserved mobility, the low implantation a short frame THV could preserve the formation of the neoskirt above the top of its frame and determining an overhang of first THV leaflets without precluding acute and short-term hemodynamics

Discussion
In consideration of the expansion of TAVI indication even in younger patients we will encounter an increase of TAVI in TAVI procedures, therefore it is essential to familiarize with CTA reconstructions to assess the risk of direct or indirect coronary occlusion and to do the best THV choice according to the cause of the dysfunction and the anatomical features.