Abstract 17754: Accuracy of Dual Source Computed Tomography to Predict Suitable Angulations for Fluoroscopic Guidance During Transcatheter Aortic Valve Implantation (TAVI)
For Transcatheter Aortic Valve Implantation (TAVI), optimal selection of fluoroscopic projections is important and often requires multiple aortic angiograms in various angulations. We analyzed the ability of Dual Source CT (DSCT) to predict suitable angulations for fluoroscopy during the TAVI procedure, including influence on procedural parameters and contrast use.
Methods: 75 consecutive patients who underwent TAVI using the Edwards-Sapien valve were evaluated. Possible angulations which would render an orthogonal view onto the aortic valve plane were determined by interactive evaluation of pre_procedural contrast-enhanced DSCT data sets acquired during i.v. injection of 40ml contrast agent. TAVI operators used a predicted angulation for the first aortic angiogram and performed additional aortic angiograms if no satisfactory view of the valve plane was obtained. Predicted angulations were compared to the angulation used for valve implantation. Differences of less than 5° (sum of LAO-RAO and CRAN-CAUD deviation) were considered as accurate prediction. Radiation exposure and contrast use was compared between patients with accurate prediction of fluoroscopic angulations by CT versus those in whom CT failed to predict a suitable view. Aortic valve calcifum was visually quantified in CT as mild, moderate, severe.
Results: TAVI was successful in all 75 patients. The mean difference between the CT-predicted angulation and the angulation used for implantation was 3±6°. CT predicted a suitable angulation in 63/75 cases (84%). The number of aortic angiograms acquired in patients with correct prediction (1.02±0.1) was lower than in patients with incorrect prediction (3.0±1.7, p < 0.001). Similarly, the amount of contrast agent required for the entire TAVI procedure was lower in patients with correct prediction (72±36ml vs. 106±39 ml, p = 0.001). Extensive calcifications of the aortic valve were associated with a lower frequency of correct prediction (100% for mild, 89% for moderate, and 71% for severe calcification, p = 0.03).
Conclusion: CT allows prediction of suitable fluoroscopy angulations during TAVI in the majority of cases, which significantly reduces the required amount of contrast.
- © 2011 by American Heart Association, Inc.