Background: Appropriateness criteria were applied to outpatient transthoracic echocardiographic (TTE) studies.
Methods: Indications were rated as appropriate, inappropriate, or unclassifiable, considering provider-stated indications, previous TTE studies, symptom changes, and patient-stated indications. Clinically important new or unexpected findings were recorded.
Results: Of 368 TTE studies, 206 (56%) were appropriate, 31 (8%) were inappropriate, and 131 (35%) were unclassifiable. Appropriateness was not correlated with patient or provider demographics. In 288 cases with prior TTE studies, there were 92 (32%) important new findings and 63 (22%) unexpected findings, of which 20% were from inappropriately ordered and 31% from unclassifiable TTE studies. Appropriateness was not associated with new (odds ratio, 1.23; 95% confidence interval, 0.48-3.18) or unexpected (odds ratio, 1.15; 95% confidence interval, 0.38-3.52) findings. Provider type and level of training were not correlated with new or unexpected findings.
Conclusions: Many indications for TTE studies were unclassifiable. A high percentage of inappropriately ordered TTE studies yielded important information. Care must be taken in judging the value of TTE studies solely on the basis of appropriateness criteria.