Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Quick, cheap blood test predicts chance of surviving heart attack

12.11.2002


A rapid and inexpensive blood test that measures levels of a hormone predicted the long-term health of patients with heart attack and chest pain, according to a study published in today’s rapid access issue of Circulation: Journal of the American Heart Association.



This hormone – B-type natriuretic peptide (BNP) – is elevated when the heart is damaged. A fragment of this hormone called the N-terminal fragment (N-BNP), can provide a clearer picture of a patient’s likelihood of survival, more so than with current prognostic methods.

"In patients with acute coronary syndromes, N-BNP measurements taken early after admission identified patients at increased risk of early and late death," says senior author Kenneth Caidahl, M.D., Ph.D., a professor in the department of clinical physiology at the Sahlgrenska University Hospital in Göteborg, Sweden. "This relationship remained significant after adjusting for conventional risk markers. The most important finding was that N-BNP also predicted mortality among patients without clinical signs of left ventricular failure."


High levels of BNP are secreted by heart tissue when the heart is overloaded with pressure and its volume is expanded. By acting as a diuretic, the hormone helps return conditions to normal. In the last few years, testing in emergency departments for elevated levels of BNP has become a quick and accurate way to diagnose heart failure, allowing for earlier and better treatment. More recently, measuring the hormone has been shown to be a reliable way to predict future heart health in patients with heart attack or chest pain (angina). Newer studies show that N-BNP may provide prognostic information superior to BNP alone.

The prognosis of patients with heart attack or angina (also called acute coronary syndromes, or ACS) varies widely, and clinical, electrocardiographic and biochemical markers are used to identify high-risk patients who need aggressive intervention with a catheter procedure or surgery.

Caidahl and colleagues sought to clarify the role of N-BNP measurement in assessing ACS. They looked at 609 patients with ACS admitted to the coronary care unit of the Sahlgrenska University Hospital from September 1995 to February 2000. Death from all causes was the primary outcome measured, starting from the time of inclusion in the study to Sept. 15, 2001. Based on hospital records and personal interviews, the patients were classified as having or not having a medical history of heart attack, chest pain, congestive heart failure, diabetes and hypertension. Patients had N-BNP levels measured approximately three days after hospital admission, an echocardiographic study within five days of hospital admission, and left ventricular ejection fraction (LVEF) measured.

The study population consisted of 204 patients with ST-elevation heart attack, 220 with non-ST segment elevation heart attack, and 185 with unstable angina. After 51 months, with follow-up ranging from 19–72 months, 86 patients (14 percent) had died. Median N-BNP levels were significantly lower in long-term survivors than in patients dying (442 vs. 1306 pmol/L). In a statistical analysis, adjusting for patient age, heart failure status, and LVEF, N-BNP remained significantly associated with dying. Those in the highest group had twice the risk as those in the lowest group.

"N-BNP and BNP appear to be stronger predictors of short- and long-term mortality than conventional biochemical risk markers, including troponins, in acute coronary syndromes," says Caidahl. "This novel blood test is an important tool for risk stratification in acute coronary syndromes and may be measured routinely in this large and important patient group in the future. A method for rapid measurement of N-BNP has recently become commercially available."

In a related editorial, James A. de Lemos, M.D., of the University of Texas Southwestern Medical School in Dallas, and David A. Morrow, M.D., M.P.H., of Brigham and Women’s Hospital in Boston, emphasize the importance of this study because it went further than similar studies by directly addressing limitations of previous analyses. They write that previous studies were "substudies within randomized controlled trials and may have enrolled highly selected patients…" and "…did not include routine measurement of LVEF." Conversely, the authors also caution that "clinical investigation of BNP in general, and in particular its application in ACS, is still in its infancy." They note that the optimal timing of measurement is not yet clear, threshold values would be useful, and direct comparisons of BNP and N-BNP are needed.

Even so, the editorial authors say that the study "answers several critical questions and contributes to a consistent emerging message: in patients with ACS, BNP adds important prognostic information to clinical and laboratory variables…." They add that the "magnitude of risk relationship associated with BNP appears to be greater than that associated with most currently available markers. Clearly BNP is telling us something that we did not previously know about factors associated with risk in patients with ACS."



###
Co-authors are Torbjørn Omland, M.D., Ph.D.; Anita Persson, M.Sc.; Leong Ng, M.D., Ph.D.; Russel O’Brien, M.D.; Thomas Karlsson, M.Sc.; Johan Herlitz, M.D., Ph.D.; and Marianne Hartford, M.D., Ph.D.

CONTACT: For journal copies only,
please call: 214-706-1396
For other information, call:
Carole Bullock: 214-706-1279
Maggie Francis: 214-706-1397


Carole Bullock | EurekAlert!
Further information:
http://www.americanheart.org/

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First diode for magnetic fields

Innsbruck quantum physicists have constructed a diode for magnetic fields and then tested it in the laboratory. The device, developed by the research groups led by the theorist Oriol Romero-Isart and the experimental physicist Gerhard Kirchmair, could open up a number of new applications.

Electric diodes are essential electronic components that conduct electricity in one direction but prevent conduction in the opposite one. They are found at the...

Im Focus: Nonstop Tranport of Cargo in Nanomachines

Max Planck researchers revel the nano-structure of molecular trains and the reason for smooth transport in cellular antennas.

Moving around, sensing the extracellular environment, and signaling to other cells are important for a cell to function properly. Responsible for those tasks...

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

 
Latest News

Helping to Transport Proteins Inside the Cell

21.11.2018 | Life Sciences

Meta-surface corrects for chromatic aberrations across all kinds of lenses

21.11.2018 | Power and Electrical Engineering

Removing toxic mercury from contaminated water

21.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>