Diagnostic Accuracy of Transthoracic Echocardiography for Endocarditis

Sensitivity and Specificity by Valve Type

The European Society of Cardiology recommends that transthoracic echocardiography (TTE) has limited sensitivity for diagnosing endocarditis, with sensitivity of 70% for native valves and only 50% for prosthetic/mechanical valves, while specificity remains high at approximately 90% across all valve types 1, 2
TTE sensitivity ranges from 40-70% for detecting vegetations in native valve endocarditis, according to the European Heart Journal 3, 1, 2
TTE specificity is approximately 90% for native valve endocarditis, as stated by the European Heart Journal 1, 2
TTE sensitivity is significantly lower at approximately 50% for prosthetic valve endocarditis, as reported by the European Heart Journal 1, 2
TTE specificity remains high at around 90% for prosthetic valves, according to the European Heart Journal 1, 2

TEE is significantly more sensitive than TTE across all valve types, with sensitivity of 96% for native valves and 92% for prosthetic/mechanical valves, as stated by the European Heart Journal 1, 2
TEE specificity is comparable to TTE at approximately 90-100% across all valve types, according to the European Heart Journal 1, 2
In prosthetic valve endocarditis, TEE is mandatory due to the poor sensitivity of TTE (50% vs 92%), as recommended by the European Heart Journal 1, 2, 4
TEE is particularly superior for detecting paravalvular complications such as abscesses and pseudoaneurysms, as reported by the European Heart Journal 3, 5

Initial TTE for all patients with suspected endocarditis is recommended by the European Heart Journal, with a positive TTE confirming diagnosis and a negative TTE in low-risk patients allowing endocarditis to be reasonably excluded 1, 2
Proceed to TEE in situations such as negative or non-diagnostic TTE with persistent clinical suspicion, presence of prosthetic or mechanical valve, suspected complications, as stated by the European Heart Journal 1, 2
Repeat echocardiography (TTE/TEE) within 5-7 days if initial examination is negative but clinical suspicion remains high, as recommended by the European Heart Journal 5, 1

TTE sensitivity is particularly limited for small vegetations (<2-3mm), recently embolized vegetations, and in the presence of pre-existing valvular lesions, as reported by the European Heart Journal 3, 5
False positive TTE findings may occur with degenerative valve disease, Libman-Sacks lesions, thrombi, and other non-infectious valve abnormalities, according to the European Heart Journal 5, 1
TTE may miss perivalvular complications such as abscesses, particularly in early stages of infection, as stated by the European Heart Journal 3, 6

The American College of Radiology notes that while TTE has lower sensitivity than TEE, specificities are similar at 91-98% for TTE and 91-100% for TEE 7
The Journal of the American College of Radiology reports that FDG-PET/CT has shown promise in identifying cardiovascular implantable electronic device infections with sensitivities ranging from 60-100% and specificities from 86-100% 7