Abstract
CONTEXT: Although computed tomography pulmonary angiography (CTPA) can confirm a diagnosis of acute pulmonary thromboembolism (PTE), its use may not be feasible in hemodynamically unstable patients. Transthoracic echocardiography (TTE) is useful to diagnose such cases but lacks specific, easily identifiable signs for differentiating acute PTE from other causes of right heart strain. AIMS: We investigated the effectiveness of the "SRC" sign, a nondilated main pulmonary artery with a dilated right atrium (RA) and right ventricle (RV), for diagnosing acute PTE. SETTINGS AND DESIGN: This was an observational, retrospective, single-center study. SUBJECTS AND METHODS: Patients with acute dyspnea and dilated RA and RV, with or without dilated pulmonary artery (PA), and those suspected of PTE according to the Wells criteria were included. Blood tests, electrocardiography, and CTPA were performed to confirm PTE diagnosis. Patients were divided into a nondilated PA and dilated RA and RV group and a dilated PA, RA, and RV group. STATISTICAL ANALYSIS USED: Chi-square test with Yates's correction was used for statistical analysis. RESULTS: Forty-one patients (27 men) with suspected PTE were included, with 36 showing a dilated RA and RV on echocardiography. The SRC sign was present in 22 patients, all of whom were confirmed via CTPA to have acute PTE. The SRC sign demonstrated 100% specificity, 100% positive predictive value, and 92.86% negative predictive value. CONCLUSIONS: TTE is valuable for assessing patients with acute dyspnea. Although RA and RV dilatation may indicate acute PTE, they are insufficient for diagnosis confirmation. The SRC sign shows high specificity for major acute PTE and may aid in decision-making.