BCR and cardiac arrhythmia: Multivariate Cox model results demonstrated that higher level of BCR was related with decreased risk of in-hospital mortality with HR of 0.66 (95% CI 0.51–0.84; P < 0.01) in participants with CS, after adjustment of age, gender, ethnicity, type of admission, ASPSII, APSIII, MCS, RRT, inotropes, vasopressors, vasopressin, mechanical ventilation, mean blood pressure, mean heart rate, chronic heart failure, cardiac arrhythmias, pulmonary circulation disease, hypertension, diabetes, renal disease, liver disease, as shown in Table 2.