CT Imaging for Percutaneous LAA Closure

Abstract

The success and procedural complexities of percutaneous left atrial appendage (LAA) closure depends largely on the LAA anatomy, and on the anatomic relations between access to the left atrium via the fossa ovalis to the LAA. These anatomic features and three-dimensional cardiac structural relationships are distinctly depicted on cardiac computed tomography angiography (CCTA), especially since the LAA has minimal dynamic role during the cardiac cycle. The spatial resolution and three-dimensional structural depiction of CCTA offers unique imaging planes not appreciated with transesophageal echocardiography (TEE), which has been the conventional pre-imaging modality-of-choice for LAA closure. As with other structural cardiac interventions, the noninvasiveness, superiority in imaging resolution and relational portrayal have progressively established CCTA as instrumental preplanning imaging tool, and is anticipated to overtake TEE as the pre-imaging modality-of-choice for LAA closure. For preplanning imaging, CCTA allows not only anatomic LAA assessment, but also ruling out preexisting thrombus in the LAA that would exclude attempt at LAA closure. In addition, post-surveillance of LAA closure is necessary to rule out device-related thrombus and residual leak, and CCTA can contribute to this important role. This chapter will review the practical utility of CCTA in preplanning and guiding LAA closure, and post-procedural surveillance.