622 APPROPRIATENESS OF ECHOCARDIOGRAPHIC REQUESTS FOR DIAGNOSIS OF INFECTIVE ENDOCARDITIS. A RETROSPECTIVE SINGLE-CENTER STUDY.


 
 
 Transthoracic echocardiography (TTE) is the first cardiac imaging modality generally requested for diagnosis of suspected infective endocarditis (IE), while transesophageal echocardiography (TEE) can be performed as initial or supplemental test. Although IE is a relatively rare disease characterized by high mortality, the number of daily in-hospital TTE and TEE requests to diagnose this disease is high, probably because of inappropriate prescriptions.
 
 
 
 The principal aim of this study was to assess the clinical appropriateness of TTE and TEE requests for suspected IE.
 
 
 
 Electronical data relative to TTE and TEE examinations performed for suspected IE between September 2013 and July 2022 at our center were extracted and retrospectively analyzed. All TTE and TEE requests were defined as appropriate according to the criteria indicated by the 2017 international guidelines on appropriateness for cardiac imaging in valvular heart disease.
 
 
 
 After exclusion of repeated ultrasound examinations, a total of 2249 first requests of echocardiographic examinations for suspected IE were analyzed (patients’ age 64±18 years, 61% males). TEE examinations were 447 (20%). Diagnosis of IE was made in 293/2249 (13%) cases. During the 10-year observation period, 33.1% of the TTE requests was appropriate and 12.2% of the appropriate examinations was positive for IE. Percentages of prescriptive appropriateness and diagnostic TTEs did not change significantly before and after publication of the 2017 international guidelines: in fact, appropriate TTE requests were 31.6% before and 35.3% after (P=0.579), and positive TTEs were 12.1% before and 12.4% after (P=0.948). Regarding TEEs, during the 10-year observation period 51.2% of the 447 examinations was appropriate and 35.8% of these evaluations was positive for IE. As for TTE, percentages did not vary significantly before and after publication of the 2017 international guidelines: appropriate TEE requests were 52.2% before and 50% after (P=0.756), and positive TEEs were 35.9% before and 35.6% after (P=0.965).
 
 
 
 The majority of echocardiography requests for diagnosis of IE at our center during a 10-year observation period was inappropriate, especially TTE requests. No significant impact of the 2017 international guidelines on appropriateness for cardiac imaging in valvular heart disease was observed. A corrective strategy could be based on several actions: periodic monitoring of prescriptive appropriateness, dissemination of knowledge about published guidelines and development of in-hospital operative protocols shared among all physicians involved in TTE and TEE prescription.
