Ventricular tachycardia incidence and erythrocyte membranes β-adrenoreactivity in patients with implanted cardioverter-defibrillator.

BACKGROUND

In patients with high risk of ventricular tachycardia (VT) the proven beneficial therapy is the implantable cardioverter defibrillator (ICD). It has been shown that the coronary artery disease (CAD) and VT development are accompanied by a persistent change of the sympathoadrenal system activity. This leads to a decrease in the total density of the erythrocyte membrane β-adrenergic receptors. The purpose of this study was to identify the relationship of the erythrocyte membranes β-adrenoreactivity (EMA) with VT development in patients with CAD and ICD.

METHOD: Sixty-three patients (male - 53, age - 66.6 ± 9.2 years) with CAD and ICD were included to the study. EMA was studied using a method for assessing erythrocyte osmoresistance increase as a result of β-adrenergic receptors blockade by a selective β-adrenergic blocker. VT and ventricular fibrillation (VF) events recorded by ICD were evaluated.

RESULTS

The 1st group consist of 23 patients with VT/VF events recorded by ICD during 27.0 [14.0; 53.0] months follow-up period. EMA indicator in this group was 41.54% [27.15; 51.26]. The 2nd group consist of 40 patients without VT/VF events and the same indicator was significantly higher - 55.42% [35.67; 62.33] (p = .04). The ROC-analysis (AUC = 0.657; Sen = 78.26; Spe = 55.00; p = .031) and binary logistic regression (OR = 0.9679; 95% CI: 0.9384-0.9983; p = .038) showed that EMA indicator 51.26% or lower was the independent predictor of VT events.

CONCLUSIONS

In patients with CAD and ICD erythrocyte membranes β-adrenoreactivity indicator 51.26% or lower is the predictor of VT episodes.