**Blood sample extraction** [6, 21].


Regarding blood culture, the following considerations must be taken into account:


**127**

**Figure 3.**

*Lead vegetation TTE.*

*Endocarditis and Cardiac Device Infections DOI: http://dx.doi.org/10.5772/intechopen.96909*

*2.6.3 Imaging*

device infection is very high (35–45%).

does not exclude the diagnosis, since sensitivity is low.

the leads, more frequent in the right cavities due to a slower flow.

and expensive technique [23].

• To the contrary, in the presence of remote bacteremia by S Aureus, the risk of

Different imaging techniques are used for the diagnosis of IE – CIED and, therefore, we will speak of Multimodal imaging when referring to them [21, 22]. First line technique, due to its availability and safety, is echocardiography. Initially, an echocardiogram should be performed in all patients with CIED infection, either local or systemic. Transthoracic echocardiogram (TTE) will allow us to globally assess all the structures of the heart as well as their function (**Figure 3**). Despite the advantage of the proximity of the right cavities to the thoracic wall, the presence of metallic electrodes generates artifacts that make it difficult to assess associated vegetations. Occasionally, images compatible with vegetations can be identified, associated with the electrodes, the valves or the endocardium; although their absence

Regardless of the result of the TTE, a Transesophageal echocardiography (TOE)

In some centers, intracardiac echo (ICE) is also used for the diagnosis of vegetations based on electrodes, with greater sensitivity for the detection of vegetations in the case of high suspicion without diagnostic images. As drawbacks, it is an invasive

In the case of uncertain diagnosis and high suspicion of endocarditis in the absence of diagnostic criteria or doubts about the extent of a local infection,

should be performed in all patients with CIED infection suspected of systemic involvement, and probably in carriers of intracardiac devices in the presence of S Aureus bacteremia (**Figure 4**). Even though the sensitivity is higher than in ETT, it is still less than 100% in the case of devices. The reasons for the low sensitivity include: the small part visualized of the cava, the difficulty to assess electrodes in the coronary sinus, or the lesser proximity to the transducer. Three-dimensional (3D) echo, if available, can provide information about vegetation's morphology and size (**Figure 5**). On the other hand, there are images that are difficult to interpret as they may correspond to fibrin strands or small thrombi adhering to the surface of

• To the contrary, in the presence of remote bacteremia by S Aureus, the risk of device infection is very high (35–45%).
