Post-TAVI Follow-Up with MDCT of the Valve Prosthesis: Technical Application, Regular Findings and Typical Local Post-Interventional Complications.

Background Transcatheter aortic valve implantation (TAVI) has evolved into an alternative procedure to surgical valve replacement for high-risk patients with aortic valve stenosis. Despite technical innovations, there is still a risk of complications during and after the intervention. After a TAVI procedure, ECG-gated multidetector computed tomography (MDCT) plays an important role in the early diagnosis of local complications. In this article, we explain for the first time how the technical acquisition of MDCT in the region of the aortic root is performed as post-interventional control of the TAVI prosthesis. In the second part normal post-interventional findings of different prosthetic valves as well as classic and uncommon complications in the implant area will be illustrated in several case studies. Methods In this review the current literature from PubMed about ECG-gated MDCT after TAVI is summarized and structured. It is supplemented by several case studies from our institution. Results and Conclusion Using retrospectively ECG-gated MDCT, an aortic valve prosthesis after TAVI can be visualized with high spatial resolution in several phases of the cardiac cycle. Images of the implanted aortic valve at all time points of the cardiac cycle enable a functional analysis of prosthetic leaflets similar to echocardiography. MDCT is superior to transthoracic echocardiography with respect to the direct detection of prosthetic leaflet thrombosis. The position of the device in relation to the coronary ostia and correct unfolding of the stent frame need to be evaluated. There are different types of stents carrying the valve leaflets with distinct ideal positions. Any stent should cover the left ventricular outflow tract (LVOT) along its whole circumference. Life-threatening complications in the implant area, such as annulus rupture, can be diagnosed reliably with CT.