TIMP1 and atrial fibrillation: High levels of TIMP-1 in either the plasma or myocardium have been found in patients with hypertension11, myocardial fibrosis, LV hypertrophy, systolic and diastolic dysfunction, atrial fibrillation, acute myocardial infarction (AMI), end-stage idiopathic dilated cardiomyopathy, and progressive HF.