Imaging for the Evaluation of Cardiovascular Infection in the Multimodality Context: ASNC I2 Imaging Series

Publication Date: March 11, 2024
Last Updated: March 12, 2024

Key Points

Echocardiography key points

  • Echocardiography plays a key role in the assessment of cardiovascular infection, including diagnosis, assessment of disease severity, prediction of shortand long-term prognosis, identification of embolic risk, management of complications, and follow-up.
  • Echocardiography provides important additional information on concomitant valvular or ventricular dysfunction, allowing for therapeutic decision-making in patients with endocarditis.
  • Characteristic echocardiographic findings comprise a major diagnostic criterion for IE.
  • Although TEE has higher sensitivity than TTE, both examinations provide independent information and should be systematically performed when cardiovascular infection is suspected.
  • The diagnostic value of both TTE and TEE is limited in some subgroups, particularly in patients with cardiac devices, prosthetic valves, or materials, including VADs. A negative echocardiographic study does not rule out infection in these groups, and additional advanced imaging can be considered for early detection of cardiovascular infection. In patients at high risk of IE, repeat TEE at approximately 1 week after a normal index study may be required for diagnosis.

Cardiac computed tomographic angiography key points

  • Cardiac CTA provides important complementary information to the valvular function obtained by echocardiography and the metabolic data obtained by 18F-FDG PET/CT and/or radiolabeled leukocyte SPECT/CT.
  • Retrospective or wide-window prospective ECG-gated acquisition of the entire cardiac cycle is preferred for dynamic valve assessment by cardiac CTA.
  • Concomitant coronary artery assessment on the same cardiac CTA scan can prevent the need for preoperative invasive coronary angiography.
  • Cardiac CTA may be combined with 18F-FDG PET/CT to assess IE-related cardiac lesions and systemic complications.
  • Definite paravalvular lesions detected by cardiac CTA are included as a major criterion for IE in the ESC 2015 guidelines.

Radiolabeled leukocyte SPECT/CT key points

  • Radiolabeled leukocyte SPECT/CT scanning is a well-established technique to image infectious processes and requires no specific patient preparation.
  • Radiolabeled leukocyte SPECT/CT is used to image IE sustained by pyogenic microorganisms, but has limited sensitivity, particularly for lesions less than 1 cm and in non-pyogenic infections.
  • It has high specificity to identify cardiovascular infection, particularly in the presence of suspected or known CIED infection or with an equivocal PET early after surgery.
  • Radiolabeled leukocyte SPECT/CT signal is included as a major criterion in the ESC 2015 guidelines for IE in patients with suspected PVE and as an additive tool in possible CIED infection.

18F-FDG PET/CT key points

  • 18F-FDG PET/CT requires specific patient dietary preparation to optimize diagnostic accuracy in assessment of certain suspected cardiovascular infection.
  • 18F-FDG PET/CT has an important additive role to echocardiography and cardiac CTA assessment in some patients with suspected cardiovascular infection.
  • This modality has higher diagnostic accuracy in suspected PVE and CIED infection compared to use in suspected NVE.
  • 18F-FDG PET/CT can identify systemic embolic phenomenon in many cases.
  • 18F-FDG PET/CT can potentially identify the portal of entry and alternative causes for sepsis.

Recommendation Grading

Disclaimer

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Overview

Title

18F-FDG PET/CT and Radiolabeled Leukocyte SPECT/CT Imaging for the Evaluation of Cardiovascular Infection in the Multimodality Context: ASNC Imaging Indications ASNC I2 Series

Authoring Organizations

Publication Month/Year

March 11, 2024

Last Updated Month/Year

March 13, 2024

Document Type

Consensus

Country of Publication

US

Document Objectives

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

Inclusion Criteria

Male, Female, Adult, Older adult

Health Care Settings

Hospital, Outpatient, Radiology services, Operating and recovery room

Intended Users

Nurse, nurse practitioner, physician, physician assistant

Scope

Diagnosis, Assessment and screening

Diseases/Conditions (MeSH)

D053821 - Cardiovascular Infections, D007962 - Leukocytes

Keywords

SPECT/CT, ASNC Imaging, F-FDG, PET/CT, Radiolabeled, Leukocyte, Cardiovascular Infection

Source Citation

Jamieson M Bourque, Ulrika Birgersdotter-Green, Paco E Bravo, Ricardo P J Budde, Wengen Chen, Vivian H Chu, Vasken Dilsizian, Paola Anna Erba, Cesia Gallegos Kattan, Gilbert Habib, Fabien Hyafil, Yiu Ming Khor, Jaimie Manlucu, Pamela Kay Mason, Edward J Miller, Marc R Moon, Matthew W Parker, Gosta Pettersson, Robert D Schaller, Riemer H J A Slart, Jordan B Strom, Bruce L Wilkoff, Adam Williams, Ann E Woolley, Brittany A Zwischenberger, Sharmila Dorbala, 18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS, Clinical Infectious Diseases, 2024;, ciae046, https://doi.org/10.1093/cid/ciae046