Beta-adrenergic reactivity of erythrocytes and the progression of heart failure in patients after myocardial infarction

Aim. To identify the associations between beta-adrenergic reactivity of erythrocytes and the progression of heart failure (HF) in patients after myocardial infarction (MI). Material and methods. The study included 50 patients with HF and history of MI 6 months ago. To determine the level of sympathoadrenal system activity, we analyzed beta-adrenergic reactivity by changing the osmotic resistance of erythrocytes by use of adrenoceptor blocking agent. Results. The frequency of HF progression after index MI was 26% (n=13). All patients were divided into 2 groups depending on the presence/absence of HF progression in the postinfarction period. When determining beta-adrenergic reactivity, it was found that patients with HF progression compared with patients without it had the higher level of beta-adrenergic reactivity of membrane (β-ARM) of erythrocytes: 58,8 (50,9; 78,0) CU and 46,8 (38,0; 66,3) CU, p=0,025). A ROC analysis made it possible to establish the β-ARM level ≥49,53 CU a cut-off point, which can be considered as a marker of HF progression in patients after MI (sensitivity 92,3%, specificity 62,2%). This level of β-ARM is associated with a more than five-fold increase of HF progression risk in patients after MI (OR 5,48; 95% CI 1,28-23,37; p=0,024). Conclusion. In patients with HF and MI history, there is a decrease in the adrenergic reactivity of erythrocyte cell membrane, which is reflected by an increase of β-ARM above normal range of 20 CU. At the same time, β-ARM in patients with HF progression compared with patients without it is significantly increased. Established cut-off point of β-ARM (≥49,53 CU) allows predicting the HF progression with high sensitivity and specificity.