In the present study we sought to investigate whether serum levels of MMP-2, MMP-3 and MMP-9 and their tissue inhibitor TIMP-1 differ in hypertensive patients with normal LV systolic function and different types of AF compared to their SR counterparts; we also evaluated associations of these markers with AF incidence and atrial structural remodeling. This evidence concerns the gene MMP9 and atrial fibrillation.