Diagnostic performance of transthoracic echocardiography in screening acute type A aortic dissection from ST-segment elevated myocardial infarction

BACKGROUND: When patients with type A acute aortic dissection (TAAAD) present with changes to their ST-segment, diagnostic and treatment delays increase significantly. The performance of transthoracic echocardiography (TTE) screening of TAAAD in patients with ST-segment elevated myocardial infarction (STEMI) is yet to be validated. METHODS: The diagnostic performance of TTE alone and combined with the aortic dissection risk score (ADRS) in TAAAD was evaluated. In this retrospective study (ChiCTR, No. 2000031291), TTE was reviewed to detect direct/indirect signs of TAAAD. The ADRS of each patient was calculated according to guidelines. Case adjudication was based on advanced imaging and surgery. RESULTS: Among a total of 442 patients, TAAAD was diagnosed in 146 (33.0%). The presence of direct TTE signs had a sensitivity of 43.0% [95% confidence interval (CI): 35.0% to 52.0%] and specificity of 97.0% (95% CI: 95.0% to 99.0%), and the presence of any TTE sign had a sensitivity of 97.0% (95% CI: 93.0% to 99.0%) and specificity of 78.0% (95% CI: 73.0% to 82.0%) for TAAAD. The additive value of TTE was most evident in patients with low clinical probability for TAAAD (ADRS ≤1). The presence of ADRS ≤1 plus an absence of direct TTE signs for TAAAD rule-out had a sensitivity of 98.4% (95% CI: 96.1% to 99.6%). CONCLUSIONS: The use of TTE adds value in the screening of TAAAD in STEMI patients. In patients with low clinical probability for TAAAD, direct TTE signs can be used to rapidly identify those who require advanced imaging.