Measuring G Protein-coupled Receptor Kinase-2 (GRK2) in the Blood to Diagnose and Treat Patients With Heart Failure

The primary objective of this study is to determine the utility of GRK2 to differentiate between normal patients and patient groups that differ by the presence/absence of HF symptoms, systolic or diastolic left ventricular dysfunction, and risk factors; and to evaluate if a new assay provides similar values as traditional methods for measuring GRK2 levels.

This study seeks to define a beta-adrenergic receptor kinase molecule in the blood and its role as an improved biomarker to be used for the diagnosis, assessment and management of patients with heart failure. We will test blood cell samples for the levels of this molecule, called "G protein-coupled receptor kinase-2" (GRK2) using both the existing method of GRK2 quantification in the Koch laboratory and using a prototype enzyme immunoassay (EIA) method being developed by Johnson \& Johnson, Ortho-Clinical Diagnostics (OCD).