The relationship between Neuropeptide Y levels and ventricular arrhythmias in patients with heart failure

Heart failure (HF) is a clinical syndrome that is frequently observed and increasing in prevalence worldwide due to the extension of average life expectancy. The causes of mortality in heart failure are progressive pump failure or sudden cardiac deaths. The most critical complications leading to sudden death in heart failure are malignant arrhythmias such as ventricular tachycardia (VT) and ventricular fibrillation (VF), with 50% of mortality attributed to ventricular arrhythmias. Excessive sympathetic activation seen in heart failure results in the release of neuropeptide Y (NPY) along with norepinephrine from nerve endings, which enhances the effect of norepinephrine. Additionally, NPY affects intracellular and extracellular calcium (Ca+2) and potassium (K+) channels, playing a role in the pathophysiology of ventricular arrhythmias. The aim of this study is to determine the relationship between NPY levels and ventricular arrhythmias in patients with HF. In our study, patients aged 18-80 years who presented to Pamukkale University Hospital between May 2022 and December 2023 and had a history of implantable cardioverter-defibrillator (ICD) implantation due to HF were included. During the device check, 40 patients who received therapy with antitachycardia pacing (ATP) or shock for ventricular arrhythmias and 40 control patients who had no observed ventricular tachyarrhythmias during follow-up device checks were enrolled. Venous blood samples were collected in biochemistry tubes for NPY from both groups. From the existing file records of the patients, hemogram, kidney function tests, electrolyte, and NT-proBNP (N-terminal pro-B type natriuretic peptide) values were recorded. A total of 80 patients were included in the study, with 40 in the patient group and 40 in the control group. The mean age of the patient group was 64.15 ± 11.88 years, while the mean age of the control group was 62.65 ± 11.04 years. In our study, there was no significant difference between the two groups in terms of age, gender, and left ventricular ejection fraction. The level of neuropeptide Y in the patient group was 236.40 ± 98.93 ng/L, while in the control group, it was 249.71 ± 99.80 ng/L (p=0.130). The Neuropeptide Y levels were 232.52 ± 90 ng/L in patients with VT and 249.76 ± 130.69 ng/L in patients with VF (p=0.294). In patients receiving therapy with shock, NPY levels were 235.18 ± 100.14 ng/L, whereas in those receiving therapy with ATP, NPY levels were 251.51 ± 99.91 ng/L (p=0.310). According to the multivariate regression analysis, low hemoglobin levels (p=0.011), the presence of chronic kidney disease (p=0.035), the use of anticoagulants (p<0.001), and the absence of hypertension (p=0.031) were predictors of VT. In our study, no significant relationship was found between ventricular arrhythmias and NPY levels in heart failure (HF) patients. However, the regression analysis we conducted demonstrated that low hemoglobin levels, the presence of chronic kidney disease (CKD), anticoagulant use, and the absence of hypertension (HT) were predictive variables for ventricular tachycardia (VT).