Aims: The aim of this study was to evaluate the role of matrix metalloproteinases (MMPs) for the prediction of long-term maintenance of sinus rhythm (SR) after cardioversion in atrial fibrillation (AF).
Methods and results: The study comprised 102 patients with AF. Pharmacological cardioversion was attempted for a 4-week period with anti-arrhythmic drugs in all patients. Those who failed medication underwent electrical cardioversion. Blood samples for biomarkers and echocardiographic data were obtained at baseline. Thirty-four patients (33.3%) converted to SR by pharmacological (n = 22) and electrical (n = 12) cardioversion and maintained it (SR group). The remaining 68 patients were refractory to the AF (RAF) group including recurrence (n = 22) and unsuccessful treatment (n = 46) after electrical/pharmacological cardioversion. Refractory AF was significantly associated with the duration of AF, hypertension, left atrial diameter, brain natriuretic peptide, MMP-2, and tissue inhibitor of MMP-2. For both multivariable logistic regression analysis and stepwise forward selection procedure, the duration of AF >5 months [odds ratio (OR) 15.32] and MMP-2 >767.0 ng/mL (OR 4.84) were significantly associated with RAF.
Conclusion: Our study suggests that elevated MMP-2 and longer AF duration increased the risk for difficulty in restoring SR in AF patients. Stratification of subjects according to the MMP-2 level may therefore be important for the effective management of AF.