The relationship between RDW (red cell distribution width) and ventricular tachicardia / fibrillation frequency in patients with implantable cardiovaryter defibrillator

Implantable cardioverter defibrillators (ICD) were invented as a new method for treating arrhythmias and sudden cardiac death. The number of new implants is increasing rapidly due to the increase in both an aging population and indications for ICD implantation. Nowadays, the use of ICD implantation shifts from secondary protection to primary protection. Red blood cell distribution width (RDW) is an index of heterogeneity of circulating red blood cell size and is used to describe some hematological system diseases. Some studies have shown that an increase in RDW may be associated with cardiovascular disease (CVD) (e.g. acute coronary syndrome, peripheral artery disease, atrial fibrillation (AF), CHF, and acute ischemic stroke). High RDW level has a negative effects on CVD. The aim of this study was to investigate the relationship between RDW and the frequency of ventricular tachycardia (VT), ventricular fibrillation (VF) and non-sustained ventricular tachycardia (VSVT) in patients with ICD. In our study, files of 122 patients who were followed up by ICD in our clinic between January-2017 and December-2018 were retrospectively surveyed. Patients were divided into three groups: the control, the VT/VF and the NSVT groups Patient information, left ventricular ejection fraction (LVEF), complete blood count [hemoglobin (HB), hematocrit (HTC), mean corpuscular volume (MCV), white blood cell count (WBC), and platelet count (PLT)], RDW, anti-tachycardia pacing (ATP) and shock, coronary artery disease, hypertension, diabetes mellitus, chronic kidney disease, and AF findings were compared. In our study, a statistically significant difference was found only between RDW and WBC results when comparing age, LVEF and blood parameters and groups. RDW (%) results were 14.75±1.44 in the control group, 18.35±19.62 in the VT-VF group and 14.80±1.82 in the NSVT group. The RDW values in the VT-VF group were significantly higher than those in the control and NSVT groups (p values 0.019 and 0.021, respectively). In other comparisons, there was no significant difference. As a result, patients with VT and VF may have high serum RDW and WBC levels. These results can be useful for the prediction, treatment, and follow-up of the VT and VF diseases. However, more detailed and randomized-prospective studies are needed for a final decision.