Role of radionuclide imaging for diagnosis of device and prosthetic valve infections

Table 1 Advantages and limitations of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography and white blood cell single-photon emission computed tomography/computed tomography for the diagnosis of device infection and prosthetic valve endocarditis

Advantages	Limitations
18F-FDG PET/CT
Excellent spatial resolution	Moderate radiation exposure (8-30 mSv depending on the study performed)
Short acquisition time	Not available in several centers
High sensitivity for the detection of hypermetabolic activity	Physiological uptake of 18F-FDG in the myocardium might prevent adequate detection of cardiac infection
Detection of peripheral events	Recent surgery may demonstrate residual inflammatory changes without evidence of infection
Detection of other sources of fever or bacteremia in patients with CIED	Possible uptakes can be found in active thrombi, cardiac tumours or metastasis, and foreign body reactions
Detection of CIED infection and PVE in cases of a negative TEE	Possible false-negative test in patients with small vegetations or prolonged antibiotic therapy
	Less useful for infectious brain embolisms because of high glucose metabolism in the brain
WBC SPECT/CT
High specificity for the presence of active infection	Time-consuming
	It involves blood products handling
	Cases of false-negative study seen with Candida and Enterococcus infection

CIED: Cardiovascular implantable electronic device;

¹⁸F-FDG PET/CT: 18F-fluorodeoxyglucose positron emission tomography/computed tomography; PVE: Prosthetic valve endocarditis; TEE: Transesophageal echocardiography; WBC SPECT/CT: Radiolabelled white blood cell single-photon emission computed tomography/computed tomography.

Table 2 Sensibility and specificity of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography and white blood cell single-photon emission computed tomography/computed tomography for both prosthetic valve endocarditis and cardiac device infection

	Test	Sensibility (%)	Specificity (%)	Positive predictive value (%)	Negative predictive value (%)	Accuracy (%)
Prosthetic valve endocarditis
Saby et al[31]	PET/CT	73	80	85	67	76
Rouzet et al[32]	PET/CT	93	71	68	94	80
	WBC	64	100	100	81	86
Erba et al[34]	WBC	90	100	100	94	N/A
Cardiovascular implantable electronic device infection
Bensimhon et al[24]	PET/CT	80	100	100	84.6	N/A
	Pocket	100	100	100	100	N/A
	Lead	60	100	100	73	N/A
Ploux et al[25]	PET/CT	100	93	N/A	N/A	N/A
Sarrazin et al[26]	PET/CT	88.6	85.7	N/A	N/A	N/A
Cautela et al[27]	PET/CT
	Pocket	86.7	100	N/A	N/A	N/A
	Lead	30.8	62.5	N/A	N/A	N/A
Ahmed et al[28]	PET/CT
	Pocket	97	98	N/A	N/A	N/A
Erba et al[29]	WBC	93.7	100	100	93.9	96.8

N/A: Not available; PET/CT: Positron emission tomography/computed tomography; WBC: White blood cell.

Table 3 Indications for the use of cardiac nuclear imaging in the context of cardiovascular implantable electronic device infection and prosthetic valve endocarditis

Accepted indication

Possible or rejected IE, but high suspicion of infection in patients with prosthetic valve

Potential indications

Unclear diagnosis of CIED infection

Evaluation of the extent of infection

Bacteremia or fever of unknown origin in patients with CIED

Cases with high clinical suspicion of IE but negative TEE and/or negative blood cultures

Search for embolic events

Monitoring the success of antibiotic therapy

CIED: Cardiovascular implantable electronic device; IE: Infective endocarditis; TEE: Transesophageal echocardiography.