Fig. 1

Association of plasma amino acids level and clinical indicators of patients. A Volcano plot of the different amino acids between persistent atrial fibrillation patients and control subjects (Student’s t-test, P < 0.05). B The distribution of feature amino acids screened by each machine learning method. The number of amino acids identified in each subset is represented in the histogram. C–D The association of plasma amino acids level and age of C control subjects and D persistent atrial fibrillation patients. E–F The association of plasma amino acids level and clinical indicators of E control subjects and F persistent atrial fibrillation patients. *P < 0.05 and **P < 0.01. BMI, body mass index. SBP, systolic blood pressure. DBP, diastolic blood pressure. FT3, free triiodothyronine. FT4, free thyroxine. TSH, thyroid-stimulating hormone. WBC, white blood cell. HGB, hemoglobin. RBC, red blood cell. PLT, platelets. ALT, alanine aminotransferase. AST, aspartate aminotransferase. ALB, albumin. Glu, blood glucose. BUN, blood urea nitrogen. Cre, creatinine. CK, creatine kinase. CK-MB, creatine kinase isoenzyme. LAD, left atrial diameter. RAD, right atrial diameter. LVEF, Left ventricular ejection fraction