P1718 Multi-modal imaging characterization of contained aortic subannular rupture after transcatheter aortic valve implantation
Authors: Grilo Diogo P , Resende C X , Nunes A , Araujo P , Torres S , Vasconcelos M , Almeida P , Rodrigues J , Madureira A , Macedo F , Maciel M J 
Published: January 2020

Abstract

INTRODUCTION
Aortic annular rupture is a potentially catastrophic complication after transcatheter aortic valve implantation (TAVI), with an estimated incidence of 1%. Rupture occurs in the anatomical device landing zone, that extends from the aortic root to the distal left ventricular outflow tract (LVOT). It usually occurs in the context of highly calcified aortic valve and LVOT, implantation of balloon-expandable valves, valve oversizing and overdilation to treat paravalvular leakage.

CASE REPORT
An 80-year old woman with no past relevant medical history was admitted to our Cardiology Department with decompensated heart failure because of symptomatic severe aortic stenosis, moderate aortic regurgitation and mild left ventricular (LV) dysfunction. She was already in waiting list for TAVI procedure, after being refused for conventional aortic valve replacement due to a "porcelain" aorta. Her pre-operative angiography showed no significant coronary heart disease, and the cardiac computed tomography (cardiac-CT) revealed a severely calcified aortic valve (Agatston score = 4940). An Acurate neo L (27mm) valve was implanted after clinical stabilization with no immediate complications. Because of paravalvular regurgitation, sequential post-dilation was performed with 25mm and 26mm balloons. Post-procedural angiography showed no contrast extravasation (Panel A). In the first hours after the procedure, she was hypotensive with non-specific mild chest discomfort. The EKG showed sinus rhythm with left anterior fascicular block. A transthoracic echocardiogram revealed a moderate pericardial effusion, with no signs of tamponade, and a moderate "paravalvular leak "at the level of the non-coronary cusp to a pulsatile cavity, between the aortic root and the left atrium (Panel B and C). The patient evolved with haemodynamic and electrical stability with no recurrence of chest discomfort. A retrospective cardiac-CT was performed that confirmed the presence of a multilobular cavity below the left coronary artery in continuous with the LVOT, compatible with a contained subannular aortic rupture (Panel E and F), at the level of previous gross calcification in the pre-operative cardiac-CT (Panel D). The case was discussed in Heart Team and a conservative strategy was adopted due to clinical stability and inoperable condition. The patient was discharged at day 28, after CT reavaluation,, that demonstrate similar findings.

CONCLUSION
We report a rare and potentially fatal complication of TAVI with a self-expandable valve. This clinical case illustrates how balloon post-dilation to treat moderate post-procedural paravalvular regurgitation lead to tearing of a highly calcified aortic annulus. A multi-modality imaging approach, with echocardiography and computer tomography, was essential for full anatomical definition of the subannular rupture, clinical decision-making and for follow-up surveillance.
Abstract P1718 Figure. Panel A,B,C,D,E,F.