Appropriateness of use criteria for transthoracic echocardiography: are they relevant outside the USA?

Appropriateness of use criteria (AUC) for transthoracic echocardiography (TTE) have been developed by American cardiology associations to help avoid unnecessary scans by formalizing indications for imaging. There are 98 indications classified as either appropriate (A), inappropriate (I), or uncertain (U). AUC may allow better targeting of limited resources, but they have not been tested systematically outside the USA.

To test AUC in Wales, one of the four countries of the UK.

We collected requests for TTE and the corresponding TTE reports from all Welsh hospitals during 1 week in June 2012 and analysed them according to appropriateness, specialty, and location (secondary vs. tertiary services) of the referring physician.

We analysed 1070 pairs of echocardiography requests and TTE reports from 14 hospitals [mean age 66.5 (16.1) years; 579 (51%) M]: A—922 (86%); I—115 (11%), and U—33 (3%); 287 (25%) studies were from two tertiary centres and 338 (29.5%) were of inpatients. Main indications were the evaluation of: cardiac structure and function (489, 45.7%), valvular function (267, 25%), and hypertension, heart failure, or cardiomyopathy (149, 13.9%). In-patient requests (main indication—‘initial evaluation of left ventricle ejection fraction post acute coronary syndrome’—44 studies, 13.7%) were more often appropriate than outpatients (main indication—‘symptoms/conditions potentially related to suspected cardiac aetiology’—142 studies, 19.8%): 94.4 vs. 83.5%, P < 0.05. The most common inappropriate indication was ‘initial evaluation for a murmur/click without symptoms/signs of structural heart disease’ (29 studies, 2.7%). The proportion of appropriate requests by specialty was 89% for medical, 87% for GPs, 85.3% for cardiologists, 80.8% for surgical, and 60% for cardiac surgeons (P < 0.05 for cardiac surgeons); 47.8% of requests were generated by cardiologists, and abnormalities were detected in 82% of all scans (37% minor findings and 45% major findings), least often in those requested by general practitioners.

Application of AUC yields results similar to those reported from the USA; ∼1 in 10 scans could be avoided.