The importance of matrix metalloproteinases in the development of atrial fibrillation in obesity

Background. One of the trends in modern cardiology is the study of the matrix metalloproteinase (MMP) system. Currently, an increase in plasma concentrations of some MMPs and their tissue inhibitors is considered as one of the earliest biochemical markers of myocardial fibrosis in various diseases of the cardiovascular system. Discusses the importance of MMP in the development of atrial fibrillation (AF).

Aim. To study the effect of the MMP system on the development of AF in obese patients.

Materials and methods. The study included 105 patients with a body mass index of more than 30 kg/m². Depending on the presence of AF, the patients were divided into 2 groups. The criterion for inclusion of patients in group 1 was the presence of documented AF paroxysm in 55 obese patients. The comparison group (group 2) consisted of 50 obese patients without heart rhythm disorders. When patients were included in the study, in order to assess the severity of visceral obesity, all patients underwent a general clinical examination, echocardiography. To determine the activity of the MMP system, venous blood was taken from patients.

Results. Significantly higher values of MMP-9 were detected in patients with obesity and paroxysmal AF – 315.7±53.4 ng/ml than in patients with obesity without heart rhythm disorders – 220.9±54.7 ng/ml (p=0.002); the values of tissue inhibitor of metalloproteinase 1 were 185.3±42.2 and 119.2±42.6 ng/ml, respectively (p=0.007). In patients with obesity and paroxysmal AF, a correlation of moderate strength between the level of MMP-9 and the volume of left atrium and a direct dependence of moderate strength between the ratio of waist volume to height and the plasma values of MMP-9 was revealed. The MMP-9 index (AUC 0.92) had a high diagnostic value for determining the probability of having a paroxysmal form of AF in obese patients. With an increase in the level of MMP-9 more than 295 ng/ml, it is possible to predict the presence of paroxysmal AF in obese patients with a sensitivity of 74.5% and a specificity of 94%.

Conclusion. In patients with obesity and paroxysmal AF, a significant increase in the parameters of the MMP system (MMP-9 and tissue inhibitor of metalloproteinase 1) was revealed when compared with obese patients without heart rhythm disorders (p<0.05). With an increase in MMP-9 of more than 285 ng/ml in obese patients, the appearance of AF with a sensitivity of 74.5% and a specificity of 94% can be predicted.