Role of Cardiac CT in Infective Endocarditis: Current Evidence, Opportunities, and Challenges

Abstract

I nfective endocarditis (IE) is infection of the endocardium. It commonly affects the valve and chordae tendineae, as well as surfaces of prosthetic valves and implanted cardiac devices (1). Diagnosis of IE is usually based on modified Duke criteria (Table 1) (2). Transthoracic echocardiography is the first-line modality used to assess for IE. Transesophageal echocardiography (TEE) has superior temporal and spatial resolution and is usually used in the evaluation of IE (3). The improved temporal and spatial resolution of electrocardiographically (ECG) synchronized cardiac CT has resulted in increasing use of CT in the setting of . The aim of this article was to review the potential role of cardiac CT in evaluating IE.

Diagnosing Endocarditis: Get the Picture?!

“…4 Thus, to enhance our ability to definitively diagnose/treat IE, new imaging modalities are now supplementing information from echocardiography, including computed tomography (CT), magnetic resonance imaging (MRI), and nuclear molecular imaging. 5,8 Cardiac CT (CCT) has gained traction as an adjunct to echocardiography, when echo is unable to offer diagnostic clarity, or if invasive testing is undesirable. CT coronary angiography (CTCA) is used to evaluate coronary artery disease, coronary artery stenosis, or coronary artery anatomy prior to cardiac surgery, in some cases in place of invasive angiography.…”

“…CT coronary angiography (CTCA) is used to evaluate coronary artery disease, coronary artery stenosis, or coronary artery anatomy prior to cardiac surgery, in some cases in place of invasive angiography. [8][9][10][11] The ability to obtain thin slices (0.65-0.75mm), the usage of ECG-gating, and post processing multiplanar reconstruction allow for the creation of a 3D image of the heart that can be viewed at various angles, all which contribute to the excellent spatial resolution seen with CCT. 8,12 Additionally, CCT provides excellent temporal resolution (although not superior to 2D echocardiography), with the ability to capture the heart at various points in the cardiac cycle.…”

“…[8][9][10][11] The ability to obtain thin slices (0.65-0.75mm), the usage of ECG-gating, and post processing multiplanar reconstruction allow for the creation of a 3D image of the heart that can be viewed at various angles, all which contribute to the excellent spatial resolution seen with CCT. 8,12 Additionally, CCT provides excellent temporal resolution (although not superior to 2D echocardiography), with the ability to capture the heart at various points in the cardiac cycle. 8,12 All of this has contributed to the increased usage of CCT in the diagnosis of IE, such that it has been incorporated into the 2015 European Society of Cardiology modified diagnostic criteria.…”

“…8,12 Additionally, CCT provides excellent temporal resolution (although not superior to 2D echocardiography), with the ability to capture the heart at various points in the cardiac cycle. 8,12 All of this has contributed to the increased usage of CCT in the diagnosis of IE, such that it has been incorporated into the 2015 European Society of Cardiology modified diagnostic criteria. 13 CCT can be used when TTE images are suboptimal and there is a contraindication to TEE, such as esophageal pathology (surgery, stricture/stenosis, or active bleeding/ulcers).…”

“…12 The presence of extensive valve calcifications, prosthetic valves, or other prosthetic material can cause a lot of image artifacts and make visualization with TEE challenging (particularly for the presence of valvular vegetations), and thus adding CCT may improve diagnostic accuracy. 8,[13][14][15] Far field structures such as the aortic annulus or tricuspid valve can be difficult to visualize with TEE, making the ability to generate of full 3D reconstruction of the heart with CCT valuable, as one can better pinpoint the exact anatomic location of vegetations on these valves. 12 CCT can be used to determine the size and anatomy of the valve or perivalvular structures to help with surgical planning, particularly with the aortic valve and root, as demonstrated by Gahide and colleagues .…”