Aortic insufficiency following transcatheter aortic valve replacement is underestimated by echocardiography compared with cardiac MRI
- 865 Downloads
KeywordsLeft Ventricular Ejection Fraction Transcatheter Aortic Valve Replacement Aortic Annulus Aortic Insufficiency Transthoracic Echocardiogram
The degree of aortic insufficiency (AI) after transcatheter aortic valve replacement (TAVR) has been identified as a predictor of increased mortality. Since even mild AI is associated with increased mortality in some studies, accurate quantification of post-TAVR AI is critical. Assessment of AI by echocardiography is typically performed by visual inspection and semi-quantitative methods. Most post-TAVR AI is paravalvular, however echocardiography has limited ability to quantify multiple eccentric paravalvular jets. Using flow quantification methods, cardiac MRI (CMR) may more accurately quantify AI severity post-TAVR and therefore more accurately assess risk in this population.
Twenty-three patients who underwent TAVR with a SAPIEN prosthesis were studied. All patients underwent an intraoperative transesophageal echocardiogram (TEE), as well as a post-procedure transthoracic echocardiogram (TTE) and CMR. Paravalvular AI by TTE and TEE was graded using color Doppler by quantifying the circumferential extent of AI as a percentage of the aortic annulus (none < 1%, trace 1-5%, mild 6-10%, moderate 11-30%, severe >30%) following recommendations from the Valve Academic Research Consortium. AI severity by CMR was quantified as the regurgitant fraction of forward aortic flow based on previously published recommendations (none <1%, trace 1-5%, mild 6-15%, moderate 16-48%, severe >48%).
CMR can reliably quantify post-TAVR AI. Echocardiography underestimates the severity of post-TAVR AI compared with CMR. CMR could be selectively utilized in patients with mild post-TAVR AI by echocardiography to screen for more significant AI. Further studies are needed to determine 1) whether echocardiography alone underestimates the risk of adverse outcomes related to post-TAVR AI, and 2) whether similar degrees of post-TAVR AI by CMR also translate into adverse outcomes.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.