Relationship of Annular Sizing Using Multidetector Computed Tomographic Imaging and Clinical Outcomes After Self-Expanding CoreValve Transcatheter Aortic Valve Replacement

Abstract

T ranscatheter aortic valve replacement (TAVR) is an alternative to surgical aortic valve replacement in patients deemed high risk or extreme risk for surgery.1-4 TAVR using the self-expanding CoreValve transcatheter heart valve (THV) was superior to medical therapy using an objective performance goal in patients at extreme risk for surgical aortic valve replacement 3 and associated with an improved survival compared with surgical aortic valve replacement in patients at increased risk for surgery. Background-Multidetector computed tomography is useful for determining the appropriate transcatheter heart valve (THV) size in patients with severe aortic stenosis who are suboptimal surgical candidates. The relationship between adherence to the recommended CoreValve sizing algorithm and clinical outcomes is not known. Methods and Results-We evaluated 1023 patients with severe aortic stenosis deemed high or extreme risk for surgery treated with the CoreValve THV. All patients underwent preprocedural multidetector computed tomography, and the scans were reviewed at a central analysis center using standardized software. Compliance to a recommended sizing algorithm was used to identify patients with below-range, in-range, and above-range THV sizing. A device annular sizing ratio (DAR) was also calculated based on the native annulus perimeter and perimeter of the selected THV. Clinical end points included the presence of paravalvular aortic regurgitation evaluated by an independent echocardiographic laboratory. Adherence to the sizing algorithm was highest with a 31-mm THV (92.6%) and lowest with the 23-mm THV (38.5%). Below-range sizing was associated with a higher rate of moderate or severe paravalvular aortic regurgitation (15.3%) than in-range (6.5%) or above-range (10.0%; P<0.001) sizing. Higher DARs were associated with lower rates of moderate or severe paravalvular aortic regurgitation: DAR ≤10%, 17.6%; DAR 10% to 15%, 9.9%; DAR 15% to 20%, 6.3%; and DAR >20%, 4.9%; P<0.001. There was no increase in clinical events associated with higher DARs. Conclusions-Adherence to a sizing algorithm guided by multidetector computed tomography resulted in lower rates of paravalvular aortic regurgitation after self-expanding transcatheter valve replacement without an increase in complications. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01240902.(Circ Cardiovasc Interv. 2016;9:e003282.

Pushing boundaries: Implantation of the 34 mm Medtronic CoreValve in patients with a large aortic annulus

“…Although there is no difference in major clinical events with in‐range and out‐of‐range transcatheter valve sizing, lower frequencies of moderate to severe PVL are evident in patients with an in‐range valve size . In fact, a DAR, as determined by [(valve perimeter – annulus perimeter)/annular perimeter] × 100, of 15% or greater was shown to have a significantly lower frequency of moderate to severe PVL . Our patients had a DAR of 5.7% and 9.3% respectively against the 34‐mm valve, and although their predicted incidence of moderate to severe PVL was almost 20%, both patients experienced only mild PVL.…”

“…With regards to the CoreValve, results of the relationship between annular sizing and clinical outcomes up to the 31 mm valve size have been reported. Although there is no difference in major clinical events with in‐range and out‐of‐range transcatheter valve sizing, lower frequencies of moderate to severe PVL are evident in patients with an in‐range valve size . In fact, a DAR, as determined by [(valve perimeter – annulus perimeter)/annular perimeter] × 100, of 15% or greater was shown to have a significantly lower frequency of moderate to severe PVL .…”

Permanent pacemaker implantation after transcatheter aortic valve replacement in bicuspid aortic valve patients

“…Oversizing of the prosthesis in regard to aortic annulus is recognized to minimize PVL and the risk of embolization. A commercial sizing chart has been developed to guide the selection of the CoreValve using aortic annular measurements, with perimeter oversizing ratio ranging from 6.9% to 30.0% for different sizes . In our cohort, perimeter oversizing >20% significantly increased the risk of PPI when compared with an oversizing ratio of 10‐20%.…”

“…This might be explained by the severe burden of calcification in this group of patients (more than 1000 mm 3 on average), which represented a challenging anatomy for optimal implantation (20.8% of patients in this subgroup ended with a depth of implantation of greater than 10 mm). Respecting the alternated “fish‐mouth” shape leaflet opening in BAV has been widely advocated recently, which usually led to smaller prosthesis size than recommended by the annulus . The leaflet opening and the annulus form a “volcanic shape” across the aortic valve leaflets, an oversizing of 10% in relation to the annulus might be an oversizing of 20% in relation to the leaflet opening.…”

“…This unequal oversizing ratio may result in unexpected lower implantation or greater compression to the anatomy. However, it has been suggested that there was an inverse relationship between oversizing ratio and moderate or severe PVL at discharge . Selection of appropriate valve size then becomes intriguing as we need to balance the risk of PPI and PVL, especially in BAV morphology.…”