Table 1.
Multimodality imaging in the assessment of patient with IE, PVE, or CIED infection.
| Echocardiography | CCTA | PET/CT | WBC SPECT/CT | CMR | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Pro | Cons | Pro | Cons | Pro | Cons | Pro | Cons | Pro | Cons | |
| General Comments | The first-line diagnostic tool. Diagnostic significance: providing information major Duke/ESC criteria. Prognostic significance: complication and prediction of the risk of embolism Able to assess treatment response. Widely available and unexpensive. TTE can be easily repeated. |
Diagnostic accuracy of TTE/TOE is operator-related. TOE requires patient sedation, not always feasible. Limiting factors: poor acoustic window (COPD, thorax conformation), artifacts due to calcium/metals. |
Diagnostic significance: major ESC criteria. Possibility to study coronary arteries at the same time. Prognostic assessment: embolisms detection with whole body contrast enhanced CT scan. Wide availability. |
Radiation exposure. Risk of contrast-induced nephropathy. |
Combination of metabolic evaluation and anatomic assessment. Diagnostic significance: major ESC criteria. Prognostic assessment: Simultaneous detection of embolism, metastatic lesions, portal of entry. Good availability. Easy to perform. Possibility to combine with CCTA evaluation of coronary tree at the same time. |
Radiation Exposure. Patient preparation for myocardial suppression. If iodinate contrast is not administrated limited value for brain assessment. Prolonged antimicrobial treatment reduce intensity of [18F]FDG uptake. Pattern of uptake is important. |
Combination of metabolic and anatomic assessment. High specificity for infection. Diagnostic significance: major ESC criteria. Prognostic assessment: simultaneous detection of embolism, metastatic lesions, portal of entry. |
Radiation Exposure. Need of blood manipulation. Limited sensitivity for small lesions. Relative complex procedure. Low availability. Long acquisition time. |
Absence of ionizing radiation. It can offer diagnostic images even without using contrast medium (can replace CCTA in patients with renal failure). It offers morphological and functional information (i.e., valve dysfunction, shunt quantification). |
Sensitive to breath artifacts (good patient compliance required). Intermediate availability. Long acquisition time. |
| Left-sided IE | Good visualization of mitral and aortic valve. Valvular dysfuction assessment. Identification of complication (i.e., valvular regurgitation). |
Difficult differential diagnosis in presence of marantic vegetations or high calcification. | Detection of vegetations and valve perforation. Assessment of perivalvular extent of disease (abscesses, pseudoaneursysm, fistula). |
Inferior to TTE/TOE in detecting small vegetations (<2 mm). | Prognostic assessment: simultaneous detection of embolism, metastatic lesions and portal of entry. | Limited sensitivity for small vegetations. | Evaluation of distant emboli and portal of entry. | Limited role because of low sensitivity for small vegetations. | Capability to assess vegetations (inferior to TTE/TOE). Capability to assess local complications. Independent by acoustic window. May detect concomitant myocardial inflammation. |
Not included in current guidelines for IE diagnosis. |
| Right-sided IE | TTE generally provides good visualization of tricuspid valve. TOE is useful in the assessment of IE related to CHD. |
Pulmonary valve is difficult to assess. | ||||||||
| PVE | Routinely used for follow up; it allows sequential assessment of prosthesis function. TOE is often required to correctly assess the prosthesis. |
Limited by prosthetic material artifacts (i.e., acoustic shadow). Early complication (i.e., abscess) can be difficult to identify. |
Identification of complications (paravalvular leakage, abscesses, pseudoaneurysm, dehiscence, and extension to adjacent structures). Capability to visualize large vegetations (>10 mm). |
Low image quality for beam hardening artifacts. Limited in assessing small vegetations (<4 mm). |
High diagnostic accuracy. Good assessment of perivalvular/periprosthetic complications. Reduction of rate of misdiagnosed PVE. Role in prediction of MACEs. Prognostic significance. |
Host reaction may reduce specificity (risk of false-positive studies until 3 months after surgery). | High specificity for infection. Reduction of rate of misdiagnosed PVE. Differential diagnosis between septic and sterile vegetations. |
Limited sensitivity for small lesions. | Image quality severely hampered by susceptibility artifacts (especially from mechanical prostheses). | |
| CIED-IE | Useful to assess intracardiac lead segments. TTE can be integrated by ultrasound evaluation of device pocket, to assessing inflamation or fluid collection. |
Limited role in the assessment of unexplorable lead segments. Differential diagnosis of vegetation vs. lead fibrosis/thrombi can be challenging. |
Possibility to combine the CT assessment of generator pocket. | Blooming and beam hardening artefacts. Poor sensitivity in detecting vegetations on leads. |
Very high sensitivity and specificity for generator/pocket and extracardiac or extravascular lead infection. | Low sensitivity for small vegetations along the leads. | Good sensitivity and specificity for generator/pocket and extracardiac or extravascular lead infection. | Limited diagnostic sensitivity for intracardiac and intravascular lead infection. | Image quality severely hampered by susceptibility artifacts from lead and device. Limited to patients with MRI conditional devices and with numerous precautions. |
|
IE: Infective Endocarditis; PVE: Prosthetic Valve Endocarditis; CIED-IE: Cardiac Implantable Electronic Device-related infective endocarditis; CCTA: Cardiac Computed Tomography; PET/TC: Fluoro-18-fluorodeoxyglucose positron emission tomography/computed tomography; WBC SPECT/CT: radiolabelled white blood cells scintigraphy with single-photon emission computed tomography/computed tomography; CMR: Cardiac Magnetic Resonance; TTE: trans-thoracic echocardiography; TOE: trans-oesophageal echocardiography; CT: computed tomography; IE: infective endocarditis; COPD: Chronic obstructive pulmonary disease; CHD: congenital heart disease; MACEs: major adverse cardiac events; CIED-IE: cardiac implantable electronic device-related infective endocarditis; MRI: magnetic resonance imaging.