Daxor Corporation (NYSE MKT: DXR
) -- The Journal of the American College of Cardiology - Heart Failure has published the first study measuring congestive heart failure patients' blood volumes at the initiation of treatment and just prior to discharge. The authors were Wayne L. Miller, MD, PhD, and Brian P. Mullan, MD. The Mayo Clinic's cardiology department is ranked #2 in the annual survey of U.S. hospitals for 2013 - 2014 according to the U.S. News and World Report.
This study involved 26 Class III/IV cardiac patients who are usually treated without blood volume measurements on the basis of clinical evaluations and tests such as hematocrits/hemoglobins, which measure the ratio of a patient's red cells but not the actual volume of a patient's blood. Retention of sodium and water and expansion of a patient's blood volume are the most fundamental derangements which occur in congestive heart failure patients. Treatment is usually based on clinical evaluations and other tests which do not measure the patient's blood volume.
The study was designed to quantitate total blood volume in patients hospitalized for decompensated heart failure and to determine the extent of volume overload and the magnitude and distribution of blood volume and water changes during diuretic therapy. Total blood volume analysis demonstrates a wide range in the extent of volume overload.
24 out of 26 patients were hypervolemic, with a range of +9.5% to +107% above the normal volume. By measuring blood volume at discharge, it was possible to compute whether the fluids removed were from the blood volume itself or from the interstitial fluid, which is the body fluid surrounding the cells of the body. On average 85% of the fluid removed came from the interstitial space. However, there was a wide range of variability within the patient population. The authors also noted that at discharge, despite vigorous therapy, most of the patients still had abnormally expanded blood volumes.
The authors noted "The extent of composition and distribution of volume overload are highly variable in decompensated congestive heart failure and this variability needs to be taken into account in the approach to individualized therapy. The authors further noted that "Utilizing current methods, the accurate assessment and management of volume overload in patients with decompensated heart failure remains problematic".
Congestive heart failure patients have a 30 to 40% death rate within one year of being admitted to a hospital for heart failure. The patients are routinely treated with powerful diuretic drugs and vasodilator medications to relax the blood vessels. Kidney failure is a frequent complication in this group of patients. This Mayo Clinic study was the first study to document the wide range of variability within individual patients with respect to the derangement of their total blood volume as well as their red cell volume.
The journal article was accompanied by an editorial by Dr. Stuart Katz, Helen L. and Martin S. Kimmel Professor of Advanced Cardiac Therapeutics; Dir NYULMC Heart Failure Program at New York University Medical Center. Dr. Katz was one of the senior authors of one of the first papers from Columbia Presbyterian Medical Center which documented that treatment which resulted in a patient having a normal blood volume (euvolemia) markedly improved the chance of survival of heart failure patients. Dr. Katz, in a detailed editorial, commented about the variability and heterogeneity of blood volume derangements in these patients. Dr. Katz concluded "Meanwhile, clinicians must recognize the limitations of physical assessment for the diagnosis of volume overload in heart failure patients, and should consider use of direct measurements of intravascular volume and/or intravascular pressures for better estimation of euvolemia as part of a therapeutic strategy to reduce the risk of adverse outcomes".
Heart failure patients constitute the greatest medical expense for hospitalized Medicare patients. Between 15 to 30% of such patients are readmitted within 30 days or less to the hospital. Medicare compensates hospitals on the basis of diagnostic related guidelines (DRGs) which means that hospitals receive a fixed cost for a specific condition such as heart failure whether the patient is in the hospital for 3 days or 15 days. There is a significant incentive to discharge patients as soon as possible. In response to the high percentage of readmission of heart failure patients, Medicare, in 2013, instituted new guidelines which penalize hospitals significantly for each patient readmitted within 30 days or less. Dr. Joseph Feldschuh, a cardiologist and the President of Daxor, noted that utilizing blood volume measurement during hospitalization and on an outpatient basis after hospitalization may decrease the necessity for repeat hospitalization by the application of more appropriate individualized therapy.