Transaortic flow velocity from dual-source MDCT for the diagnosis of aortic stenosis severity

Does frame geometry play a role in aortic regurgitation after Medtronic CoreValve implantation?

AIMS

Aortic regurgitation (AR) after Medtronic CoreValve System (MCS) implantation may be explained by patient-, operator- and procedure-related factors. We sought to explore if frame geometry, as a result of a specific device-host interaction, contributes to AR.

METHODS AND RESULTS

Using rotational angiography with dedicated motion compensation, we assessed valve frame geometry in 84 patients who underwent TAVI with the MCS. Aortic regurgitation was assessed by angiography (n=84, Sellers) and echocardiography at discharge (n=72, VARC-2). Twenty-two patients (26%) had AR grade ≥2 using contrast angiography, and 17 (24%) by echocardiography. Balloon predilatation and sizing and depth of implantation did not differ between the two groups. Despite more frequent balloon post-dilatation in patients with AR (40.9 vs. 9.7%, p=0.001), the frame was more elliptical at its nadir relative to the patient's annulus (6±13 vs. -1±11%, p=0.046) and occurred in a larger proportion of patients (61.9 vs. 26.8%, p=0.004). Although the Agatston score and the eccentricity of the MCS frame relative to the annulus were independent determinants of AR (odds ratio: 1.635 [1.151-2.324], p=0.006, and 4.204 [1.237-14.290], p=0.021), there was a weak association between the Agatston score and the adjusted eccentricity (Spearman's rank correlation coefficient =-0.24, p=0.046).

CONCLUSIONS

These findings indicate that AR can be explained by a specific device-host interaction which can only partially be explained by the calcium load of the aortic root.

Limitations and difficulties of echocardiographic short-axis assessment of paravalvular leakage after corevalve transcatheter aortic valve implantation

To make assessment of paravalvular aortic leakage (PVL) after transcatheter aortic valve implantation (TAVI) more uniform the second Valve Academic Research Consortium (VARC) recently updated the echocardiographic criteria for mild, moderate and severe PVL. In the VARC recommendation the assessment of the circumferential extent of PVL in the short-axis view is considered critical. In this paper we will discuss our observational data on the limitations and difficulties of this particular view, that may potentially result in overestimation or underestimation of PVL severity.

Reducing periprocedural complications in transcatheter aortic valve replacement: review of paravalvular leaks, stroke and vascular complications

Transcatheter aortic valve replacement has been established as the standard of care for inoperable patients and a valid alternative for high-risk individuals with severe symptomatic native aortic stenosis. Over the last decade, substantial improvement has been made in the transcatheter technology. Nevertheless, this less-invasive procedure is still associated with complications like paravalvular leaks, strokes and vascular complications. This review article discusses these worrisome complications associated with transcatheter aortic valve replacement and proposes methods to prevent these hurdles.

An insight into transcatheter aortic valve implantation-a perspective from multidetector-computed tomography

Transcatheter aortic valve implantation (TAVI) has now become an acceptable alternative to surgical aortic valve replacement for patients with severe aortic stenosis at high risk. The early enthusiasm for this technology has not diminished but rather has developed at an unprecedented rate over the last decade. Alongside the developments in implantation technique, transcatheter design, and postprocedural care, cardiac imaging modalities have also had to concurrently evolve to meet the perpetual demand for lower peri- and postprocedural complication rates. Although transthoracic and transesophageal echocardiography remain vital in patient's selection and periprocedural guidance, there is now emerging evidence that indicates that multidetector-computed tomography (MDCT) may also have an equally important role to play. The aim of the current review is to examine the modern role of MDCT in assessing patients with aortic stenosis being considered for TAVI.

An update on complications associated with transcatheter aortic valve implantation: stroke, paravalvular leak, atrioventricular block and perforation

Transcatheter aortic valve implantation (TAVI) has become an alternative therapeutic option for patients with symptomatic severe aortic stenosis at high surgical risk and the standard of care in patients who are inoperable for open aortic valve replacement. With technological evolution and increasing experience, the procedure has become more predictable. Complications of TAVI, however, are not infrequent, and can range from minor to life-threatening events. Stroke, paravalvular leak, various forms of atrioventricular block, including the need for permanent pacemakers and aortic annular and ventricular perforation will be the focus of the present review. Other complications associated with TAVI (such as vascular injury, acute kidney injury, coronary obstruction, valve malpositioning or migration) are clinically important, but are beyond the scope of this article. Understanding the occurrence and pathophysiology of these complications may provide insights into the improvement of the transcatheter devices and techniques, and aid in extending the application of TAVI to a broader population.