Background and aim of the study: The predictive value of chronic atrial fibrillation (AF) before percutaneous mitral balloon valvotomy (PMBV) is still under discussion. The effect of the duration of chronic AF on short- or long-term results is not known. Therefore, we analyzed the predictive value of pre-procedural chronic AF and the duration of this rhythm disturbance for short- and long-term outcome after PMBV in patients with mitral valve stenosis.
Methods: A total of 140 PMBV procedures was performed in 137 patients with severe mitral stenosis. Sixty-three patients (45%) were in chronic AF; in 40 patients (63%) the AF was of more than one year duration. A successful procedure is defined as PMBV achieved without acute mitral valve replacement, and a mitral valve area after PMBV of > or =1.5 cm2.
Results: Patients in chronic AF were significantly older, had a larger left atrial diameter and higher NYHA functional class, compared with patients in sinus rhythm (SR). The success rates of PMBV were 80.5% and 77.6% in patients with SR and AF, respectively (p = NS). Mean follow up was 4.2+/-2.6 years (n = 127). At four years' follow up the event-free survival was 86.5% in patients with SR, and 78.5% in those with chronic AF at baseline (p = 0.031). Multivariate analysis of the entire study population showed the presence of chronic AF to be the only pre-procedural independent predictor for severe mitral regurgitation after PMBV (p = 0.030), as well for an event (p = 0.039) and restenosis (p = 0.034) during follow up. The risk for an event or restenosis during follow up increased seven-fold when chronic AF at baseline was present for more than one year (p = 0.010).
Conclusion: Pre-procedural chronic AF is an independent predictor for unfavorable outcome at short- and long-term follow up after PMBV. A longer duration of AF further increases the risk of an event or restenosis.