Systolic blood pressure, a readily available vital sign taken at hospital admission, has been found to be a key factor in predicting mortality risk and revealing important disease characteristics for heart failure patients, according to a team of academic researchers.

These new findings indicate that heart failure patients with higher systolic blood pressures had substantially lower death rates compared to patients with lower systolic pressures, and that lower systolic pressures may indicate more advanced disease and a poorer prognosis.

Published in the Nov. 8 issue of the Journal of the American Medical Association, the new study found that the level of systolic blood pressure taken at hospital admission offers insight into different stages of heart failure, prognosis, and disease development. This study also revealed that systolic hypertension is very common in patients admitted to the hospital for heart failure -- present in over 50 percent of patients.

"Systolic blood pressure taken at hospital admission was a strong independent predictor of mortality and morbidity in this large, representative heart failure patient population. We hope the findings may help clinicians more effectively stratify risk and offer more targeted treatments based on a patient's systolic blood pressure level," said Dr. Gregg C. Fonarow, The Eliot Corday Chair in Cardiovascular Medicine and Science, principal investigator and director, Ahmanson-UCLA Cardiomyopathy Center.

Systolic blood pressure demonstrates the maximum arterial pressure during contraction of the left ventricle of the heart -- typically the first number in a blood pressure reading (for example, 120 mm Hg when the blood pressure is reported as 120/80 mm Hg -- measured in millimeters of mercury). Heart failure occurs when the heart is not working effectively, including when the heart's left ventricle can't pump enough blood to the body's other organs.

The study is the first to utilize patient data from a large heart failure patient registry called the Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients with Heart Failure (OPTIMIZE-HF). Researchers included information on 48,612 heart failure patients seen at 259 U.S. hospitals between March 2003 and December 2004.

Researchers found that patients with higher systolic blood pressures at hospital admission had substantially lower in-hospital and post-discharge mortality rates compared to patients with lower systolic pressures. This finding applied to patients irrespective of their left ventricular ejection fraction, a common measure of ventricular function.

"Elevated systolic blood pressure appears to signal specific pathophysiological processes that differ from the underlying processes in patients with low systolic blood pressure. Because the characteristics and outcomes are different among patients with heart failure with varying systolic blood pressure levels, management may need to vary according to this readily available vital sign." said Dr. Mihai Gheorghiade, professor of medicine, division of cardiology, Feinberg School of Medicine, Northwestern University and first author of the study.

The study revealed the following in-hospital mortality rates by systolic blood pressure levels: 7.2 percent mortality rate for patients with low systolic pressures of less than 120 mm Hg.; 3.6 percent mortality rate for patients with pressures between 120 and 139 mm Hg (generally considered in the normal range); 2.5 percent for patients with higher systolic pressures between 140-161 mm Hg; and 1.7 percent mortality rate for patients with very high systolic pressures over 161 mm Hg.

"We found that despite current pharmacologic therapies, the lower the admission systolic blood pressure level, the higher the patient mortality rate," said Gheorghiade.

According to researchers, it had traditionally been thought that most patients with heart failure had lower systolic blood pressures when they presented to the hospital with worsened heart failure, but the study revealed that over fifty percent of patients had a high systolic blood pressure -- over 140 mm Hg.

"To optimize treatment, we may need to medically approach heart failure patients differently depending if their systolic blood pressures are normal, low or high," said Fonarow.

Researchers note that systolic blood pressure may be an indicator of the stage of heart failure with lower systolic blood pressures indicating more advanced disease and prognosis. Clinical trials designed for each patient group may lead to more insight into heart failure disease development.