Background: Electrical cardioversion (EC) remains the most effective treatment for the restoration of sinus rhythm in patients with atrial fibrillation (AF). During the development of AF, structural remodeling (besides electrical remodeling) and inflammation could play a pivotal role in perpetuation and recurrence of the arrhythmia after EC. The aim of this study was to evaluate the role of inflammation [as indicated by C-reactive protein (CRP)] and matrix degradation [matrix metalloproteinase type I, MMP-1, its tissue inhibitor, TIMP-1 and carboxy-terminal telopeptide of collagen type I, ICTP)] on the success of EC and maintenance of sinus rhythm.
Methods: We studied 46 patients (66+/-12 years; 75% men) who underwent direct current EC for persistent AF (mean duration: 30 weeks). Blood samples were drawn immediately prior to, and at one month post-EC. Baseline parameters were compared to 40 healthy subjects in sinus rhythm ('controls').
Results: Patients with AF had increased levels of CRP (p=0.04) and lower levels of MMP-1 (p=0.002) compared with controls. EC was successful in 78%. There were no differences in baseline levels of CRP, MMP-1, TIMP-1 and ICTP between those where EC was unsuccessful, compared to those with immediate EC success. Patients who maintained sinus rhythm at 30 days' follow-up had lower levels of CRP (p=0.03) and ICTP (p=0.01).
Conclusion: Inflammation and abnormal indices of matrix degradation pre-EC were not associated with the immediate EC success. Maintenance of sinus rhythm at 1 month was associated with lower CRP and ICTP levels.