Spectral CT Imaging of Prosthetic Valve Embolization after Transcatheter Aortic Valve Implantation

Abstract

Transcatheter heart valve (THV) embolization is a rare complication of transcatheter aortic valve implantation (TAVI) generally caused by malpositioning, sizing inaccuracies and pacing failures. The consequences are related to the site of embolization, ranging from a silent clinical picture when the device is stably anchored in the descending aorta to potentially fatal outcomes (e.g., obstruction of flow to vital organs, aortic dissection, thrombosis, etc.). Here, we present the case of a 65-year-old severely obese woman affected by severe aortic valve stenosis who underwent TAVI complicated by embolization of the device. The patient underwent spectral CT angiography that allowed for improved image quality by means of virtual monoenergetic reconstructions, permitting optimal pre-procedural planning. She was successfully re-treated with implantation of a second prosthetic valve a few weeks later.

Pre-TAVI imaging: an Italian survey by the CT PRotocol optimization (CT-PRO) group

“…In this setting, CT angiography allows to obtain accurate measurements for pre-operative planning, also thanks to increased spatial and temporal resolution of modern CT platforms [ 7 ]. However, poor image quality, wrong acquisition protocols and deviations from guidelines may lead to incorrect measurements and potentially fatal periprocedural complications [ 8 , 9 ]. Recently, the European Society of Cardiovascular Radiology (ESCR) and the Society of Cardiovascular Computed Tomography (SCCT) have published expert consensus documents suggesting the acquisition protocol for pre-TAVI CT angiography, and standardized measurements or nomenclature that should be reported [ 10 ].…”

The value of metal artifact reduction and iterative algorithms in dual energy CT angiography in patients after complex endovascular aortic aneurysm repair

“…DECT allows reconstruction of Virtual Monoenergetic Images (VMIs) to enhance the contrast of intravascular iodine and surrounding tissues, improving the diagnostic value of the examination in terms of, e.g., assessment of vascular stenosis, detection of endoleaks, post-procedural assessment of thoracic aorta [ 9 , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] ]. Use of monoenergetic reconstructions with low photon energies (40–60 keV) permits obtaining very high attenuation values associated with the properties of the K absorption curve characteristic of iodine [ 29 ].…”