TCT-768 Novel use of Aortic Valve IVUS to Guide Transcatheter Aortic Valve Implantation

Abstract

Background: Accurate imaging of the aortic anatomy during Transcatheter Aortic Valve Implantation (TAVI) is important as poor valve sizing may adversely affect patient outcomes. Methods: The aim of this study was to evaluate the feasibility of a using a large field intravascular ultrasound (IVUS) catheter (Visions PV0.35,Volcano corporation,San Diego, CA) to guide valve sizing in TAVI. The catheter has a maximum imaging diameter of 60 mm (as compared to <20 mm for coronary IVUS) and uses 10MHz frequency ultrasound. The catheter is 8.5F sheath compatible and advanced in an over-the-wire technique over a 0.35 wire. Results: We performed aortic valve IVUS on 18 consecutive patients (mean age 81 3years, mean EuroSCOREII 16.6.0 8.5%, mean STS score 7.5 4.4%) for planned transfemoral TAVI with the CoreValve (Medtronic, Minneapolis, MA). IVUS imaging was performed pre-TAVI over a stiff 0.35 wire in the left ventricle. All 18 patients also had intra-procedure Trans-Oesophageal Echocardiography (TOE) and 16 of the 18 patients had pre-TAVI Multi-Detector Computed Tomography (MDCT) to guide valve sizing. All patients had successful IVUS imaging with measurement of minimum/maximum annulus diameters and annulus area/ perimeter. Of the patients who had MDCT and IVUS, the annulus measurements were compared. The mean annulus area was 398.8 80.2mm2 by IVUS and 390.4 63.7mm2 by MDCT while the mean perimeter was 79.6 6.7mm by MDCT and 79.0 8.1mm by IVUS. There was a positive correlation between the IVUS and MDCT annulus area and annulus perimeter measurements (annulus area p1⁄40.19,r1⁄40.89,95%CI 0.72-0.95;annulus perimeter p1⁄40.11, r1⁄40.91,CI 0.77-0.96) which was not statistically significant. The mean ellipticity index (EI) was greater when measured with IVUS (1.23) than when measured with MDCT (1.21,p1⁄40.03). Also of interest was IVUS imaging post TAVI which demonstrated valve leaflet function as well as frame expansion. There were no procedural complications associated with the use of this technique. Conclusions: Using IVUS to guide TAVI is feasible and warrants further evaluation and comparison with other multi-modality imaging. The technique is fast, safe and intuitive to operators with experience in coronary IVUS.