TIMP4 and atrial fibrillation: MMP2/TIMP4 and MMP16/TIMP4 ratios were also tested, with the former demonstrating a tendency towards significance (3.87 ± 1.22 vs 7.96 ± 1.58, p = 0.063), while the latter was significantly decreased in AF patients (0.07 ± 0.02 vs 0.24 ± 0.05, p = 0.006).