Increased C-reactive protein plasma levels are not involved in the onset of post-operative atrial fibrillation.

BACKGROUND: Increased inflammation biomarkers plasma levels, including C-reactive protein (CRP), have been associated with the initiation and perpetuation of atrial fibrillation (AF). However, it is not known whether an increased CRP plasma level, without concomitant inflammation, is sufficient to induce AF. We investigated whether higher CRP plasma levels, determined by the presence of +219G>A CRP gene polymorphism, is associated with an increased risk of post-operative AF.

METHODS: One hundred and fifteen adult patients submitted to elective coronary surgery were genotyped for the CRP +219G>A polymorphism. CRP plasma levels were determined by enzyme-linked immunosorbent assay.

RESULTS: CRP plasma levels before surgery were higher in GG than in GA+AA patients (3.4±3.1 vs. 1.7±1.8, p<0.015). Thirteen percent of the patients presented post-operative AF. Despite the positive correlation between the polymorphism and CRP levels, there was no significant difference in the occurrence of post-operative AF between the different genotypes.

CONCLUSIONS: These results suggest that increased CRP plasma levels that are not associated with an inflammatory process are not sufficient to trigger AF after cardiac surgery.