A study analyzing the ratio between MMP-1 and its inhibitor TIMP-1 in cardiac tissue of patients with hypertensive HF by western blot and immunohistochemistry found that probands presenting with HFrEF had an excess of MMP1 relative to TIMP1, while the ratio in patients presenting with HFpEF was comparable with healthy individuals (10). Here, TIMP1 is linked to hydrops fetalis.