Multislice CT Assessed for Prediction of Optimal Angiographic Deployment Projections During TAVI

November 22, 2010—A study assessed whether multislice computed tomography (MSCT) could predict optimal angiographic projections for visualizing the plane of the native valve and facilitating accurate positioning during transcatheter aortic valve implantation (TAVI). Ronen Gurvitch, MBBS, et al published the study's findings in the Journal of the American College of Cardiology: Cardiovascular Interventions (2010;3:1157–1165). The background of the study is that accurate device positioning during TAVI depends on valve deployment in angiographic projections that are perpendicular to the native valve plane, but these may be difficult to determine.

As detailed by the investigators, 20 patients underwent MSCT before TAVI. Using a novel technique, multiple angiographic projections accurately representing the native valve plane in multiple axes were determined. The accuracy of all predicted projections was determined postprocedure using angiography according to new criteria, based on valve perpendicularity and the degree of strut overlap (defined as excellent, satisfactory, or poor). The accuracy of valve deployment using MSCT was compared with the results of 20 consecutive patients undergoing TAVI without MSCT angle prediction.

The investigators reported that correct final deployment projections were more frequent in the MSCT-guided procedure compared with the non–MSCT-guided group: excellent or satisfactory projections (90% vs 65%; P = .06). The MSCT angle prediction was accurate but dependent on optimal images (optimal images, 93% of predicted angles were excellent or satisfactory; suboptimal images, 73% of predicted angles were poor). A “line of perpendicularity” could be generated with optimal projections across the right-to-left anterior oblique plane by adding the correct cranial or caudal angulation.

The investigators concluded that preprocedural MSCT can predict optimal angiographic deployment projections for implantation of transcatheter valves and that an ideal deployment angle curve or line of perpendicularity can be generated. Understanding and applying these principles improves the accuracy of valve deployment and may improve outcomes.