Associated factors with the occurrence of inappropriate shocks among admitted patients with ischemic cardiomyopathy

It has been previously shown that Implantable Cardioverter-Defibrillator (ICD) shocks are associated with subsequent increased mortality risk in patients with heart failure. We designed this study to assess the factors related to ICD shocks in patients with ischemic cardiomyopathy (ICM).

Eighty consecutive patients with ICM underwent primary or secondary preventive ICD implantation, and experienced shocks were recruited in this cross-sectional study between March 2018 and March 2019. Patients were grouped based on the presence of appropriate or inappropriate ICD therapy. Data on demographic, clinical, laboratory and medications of eligible patients were assessed to identify ICD shocks related factors with univariate and multiple adjusted models.

The mean age of the total population was 65.4 ± 9.8 years (males: 86.3%). Eleven patients (13.7%) experienced inappropriate shocks. The presence of sinus tachycardia was 7.38 (95% confidence interval (CI): 1.78-30.56, P= 0.006), which was associated with higher likelihood of inappropriate shock occurrence. Moreover, patients with atrial fibrillation (AF) had significantly elevated odds of inappropriate shock frequency (odds ratio (OR): 4.32, 95% CI: 1.15-16.13, P= 0.02).

Our findings indicate that the presence of sinus tachycardia and prior AF could significantly increase the likelihood of inappropriate shock frequency among patients with ICM using ICDs. Further large-scale studies are required to prove our outcomes.