C-reactive protein and transesophageal echocardiographic markers of thromboembolism in patients with atrial fibrillation.

Background: To determine whether C-reactive protein (CRP) in combination with a stroke risk stratification scheme can help in identifying transesophageal echocardiographic (TEE) markers of thromboembolism such as left atrial (LA)/left atrial appendage (LAA) thrombus, severe LA/LAA spontaneous echocardiographic contrast (SEC), and aortic plaque ≥ 4 mm.

Methods: Transthoracic echocardiography, TEE, and CRP measurement were performed at admission in 178 patients with non-valvular atrial fibrillation not receiving oral anticoagulant therapy. Patients were classified as at low, moderate, or high risk of thromboembolism based on seven clinical risk stratification schemes (SPAF, CHADS(2), Framingham, Birmingham/NICE, ACC/AHA/ESC 2006 guidelines, ACCP 2008, CHA(2)DS(2)VASc).

Results: Severe LA/LAA SEC, LA/LAA thrombus, and aortic plaque ≥ 4 mm were present in 6.2%, 6.7%, and 10.1% of patients, respectively. The combination of CRP with a cut-off value of 3.4 mg/L with the Birmingham/Nice or ACC/AHA/ESC 2006 risk score, led to a negative predictive value of 100% in low-risk patients and 91% in moderate-risk patients. For the detection of severe LA/LAA SEC or thrombus, a good discrimination (area under curve ≥ 0.70) using only clinical risk markers was observed for all classifications except for the Framingham and CHADS(2) risk scores. The addition of CRP did not improve the detection of LA/LAA SEC or thrombus, or of severe LA/LAA SEC, thrombus, or aortic plaque.

Conclusion: The combination of clinical risk markers and CRP can help to exclude the presence of the TEE markers LA/LAA SEC or LA/LAA thrombus, particularly in patients classified at low or moderate risk of stroke.