The role of the post-cardioversion time course of hs-CRP levels in clarifying the relationship between inflammation and persistence of atrial fibrillation.

OBJECTIVES

Although recent studies suggest that inflammation is involved in the pathogenesis of atrial fibrillation (AF), it remains controversial whether it is a consequence or a cause of the arrhythmia.

DESIGN

Prospective study.

SETTING

Tertiary referral centre.

PATIENTS AND INTERVENTIONS

In 52 patients with persistent AF lasting >3 months, high-sensitivity C-reactive protein (hs-CRP) was measured before and after electrical cardioversion.

MEASUREMENTS AND RESULTS

All patients were successfully cardioverted to sinus rhythm (SR), but the recurrence rate was 23% at 1 month. Baseline hs-CRP was higher in patients with AF recurrence than in those who remained in SR (0.5 (SD 0.18) mg/dl vs 0.29 (SD 0.13) mg/dl, respectively, p<0.001). Similarly, arrhythmia recurrence was associated with greater left atrial diameters (45.4 (SD 3.3) mm vs 40.7 (SD 3.1) mm, respectively, p<0.001). However, logistic regression analysis showed that hs-CRP was the only independent predictor for AF recurrence (p<0.001). Additionally, patients who were in SR on final evaluation had significantly lower hs-CRP levels than at baseline (0.10 (SD 0.06) mg/dl vs 0.29 (SD 0.13) mg/dl, respectively, p<0.001), while those who experienced AF recurrence had similar values on final and on initial evaluation (0.56 (SD 0.24) mg/dl vs 0.50 (SD 0.18) mg/dl, respectively, p = 0.42).

CONCLUSION

High levels of hs-CRP are associated with an increased risk of AF recurrence after cardioversion. The restoration and maintenance of SR result in a gradual decrease of hs-CRP while AF recurrence has a different effect, suggesting that inflammation is a consequence, rather than a cause, of AF.