MMP8 and atrial fibrillation: Thirdly, patients with funisitis had a significantly higher median AF MMP-8 than those without funisitis (433.7 ng/mL vs. 1.9 ng/mL; p < 0.001), and the diagnostic indices of MMP-8 (cutoff, 23 ng/mL) in the identification of funisitis were sensitivity of 90%, specificity of 78%, positive predictive value of 55%, and negative predictive value of 96% [45].