The study by Dr. Ajijola, published in JAMA Cardiology, found that elevated coronary sinus neuropeptide Y (NPY) level is associated with adverse cardiovascular events in stable patients with chronic heart failure and therefore, it may have prognostic value in this population.
Increased cardiac sympathetic signaling has been associated with adverse cardiovascular outcomes. Biomarkers of the sympathetic system are of significant interest in the assessment of cardiovascular outcomes. NPY is one of the circulating catecholamines, which may predict the risk of death in patients with chronic heart failure.
Dr. Ajijola and his colleagues conducted a prospective observational cohort study at a single-center, tertiary care hospital. They observed 105 patients with stable heart failure undergoing elective cardiac resynchronization therapy (CRT) device implantation between 2013 and 2015. Patients with NYHA class I, severe aortic stenosis, cardiac surgery within prior 90 days, severe obstructive pulmonary disease requiring oxygen or with recent decompensation (< 30 days), current pregnancy, primary pulmonary hypertension, continuous intravenous drug infusion for heart failure, and life expectancy under 6 months were excluded from the study. At the time of the intervention, the coronary sinus blood sample was taken and checked for the NPY levels. Patients were evaluated for major adverse cardiovascular events (MACE) as well as responses to CRT. Composite endpoint was defined as death, cardiac transplant (OHT), or ventricular assist device (VAD) placement.
The results of the study showed that NPY levels of coronary sinus were associated with prognostic implications in patients with heart failure. 20 out of 105 (19%) patients showed composite endpoints at a median follow-up of 29 months. Also, the NPY levels of greater than 130 pg/mL were associated with worse outcomes compared with those with lower levels (HR, 8.9; 95% CI, 3.1 – 25.7; P < 0.001). The results remained significant even after adjusting for age, eGFR, and LVEF (HR, 9.5; 95% CI, 2.92 – 30.5; P < 0.001). According to Dr. Ajijola, “Coronary sinus NPY levels may identify patients in whom close clinical monitoring and more aggressive interventions are needed to prevent adverse events. It may also identify those in whom CRT is likely to be ineffective, and such patients may be considered sooner for OHT or VAD.”
This study is limited by some points. First, although NPY levels were irrespective of CRT response, the presence of CRT devices limits the external validity of the study. Second, the sample size was small for formal statistical validation of the study including the NPY thresholds. Future studies are warranted to further validate the results of this study and to clarify the prognostic value of NPY levels.