Dear editor,

I read a recently published manuscript by Gazilli et al with great interest1. The authors have recommended new interpretation criteria to diagnose infective endocarditis.

Interestingly, the authors have excluded 9 patients with other inflammatory reasons in the HSBM analysis. Although, it is not clear whether they included these 9 patients in the HSBM analysis who were considered as false-positive cases or completely excluded from the analysis. Table 2 includes two columns with Deauville-like and HSBM scores; however, the values in the table are similar to numbers/percentages provided in the text for Native Valve IE (third paragraph in the “results” section). If this is an error, then it would be great interest to the readers to see sensitivity, specificity, PPV, and NPV for HSBM analysis. Also, the authors have mentioned in the “new knowledge gained” section that “combination of direct and indirect criteria lead more reliable imaging method in diagnosing infective endocarditis,” however, there are no data to support the combination of these two methods; therefore, additional analysis would be ideal for supporting this claim.

Lastly, in the discussion, the authors have mentioned that for small vegetations, gated cardiac PET/CT may be helpful. Is there any data to support findings that having gated cardiac PET/CT would increase SN or SP for detection of small vegetations? I believe the critical part here, as they mentioned, is the avascular nature of the vegetation, and thus, spatial/temporal resolution is the main limitation, rather than gating.

I congratulate the authors on this interesting, well-designed study, which is a great addition to IE imaging literature!

Sincerely,

Ayaz Aghayev, MD