Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Blood test can accurately diagnose heart failure in emergency patients

11.04.2005


Measuring protein level provides accurate assessment for patients with shortness of breath

A new blood test that measures a particular marker of cardiac distress can markedly improve the ability to diagnose or exclude congestive heart failure in patients with shortness of breath who come to hospital emergency departments. The report from researchers at Massachusetts General Hospital (MGH) finds that measuring levels of a protein called NT-proBNP was significantly better at identifying heart failure than was standard clinical evaluation. The report will appear in the April 15 issue of the American Journal of Cardiology and has been released online prior to print publication.

"We found that testing with the NT-proBNP assay was an extremely accurate way to identify or exclude heart failure in patients with shortness of breath," says James Januzzi Jr., MD, of the MGH Cardiology Division, the paper’s lead author. "Importantly, we also found that the very best results came from combining the results of this very sensitive and specific blood test with the logic and wisdom of a good emergency physician, which gave the optimal balance between biologic data and clinical judgement."



Congestive heart failure, which occurs when an impaired heart muscle cannot pump blood efficiently, is a growing health problem and major cause of cardiac death. The diagnosis of heart failure may be difficult to make because its typical symptoms can overlap with those of other conditions. Missing a heart failure diagnosis can put patients at high risk of serious problems, including death, but overdiagnosis may lead patients to receive unnecessary treatment.

"To date, the way physicians have traditionally evaluated potential heart failure patients has been rather random, with some receiving a physical examination and medical history while others also get expensive and time-consuming procedures," Januzzi says. "Having a widely-available, accurate, and cost-effective diagnostic method would be of extraordinary value."

Proteins called natriuretic peptides are produced when the cardiac muscle is under stress. The role of testing for these proteins in several forms of cardiovascular disease has been the subject of intense recent study. In 2002, the newest generation of natriuretic peptide assays became available, and soon thereafter the current investigation – called the PRIDE study – was launched to determine the usefulness of a test for NT-proBNP in evaluating emergency patients. At the time of its launch, the PRIDE study was the first prospective American trial of NT-proBNP and the largest such study to study the test in patients with shortness of breath.

About 600 patients who came to the MGH Emergency Department with shortness of breath were enrolled in the study. In addition to standard evaluation of symptoms, a blood sample was drawn for NT-proBNP measurement. After the emergency assessment was completed, the attending physicians were asked to estimate the likelihood that the patients’ symptoms were caused by heart failure, based on all available information except the NT-proBNP assay. For patients admitted to the hospital, the entire record of their stay was included in the study data. Sixty days after the original emergency visit, the researchers followed up with each patient, contacting them personally and reviewing their records to identify any subsequent clinical events. Participation in the study in no way changed the care or treatment the patients received.

To determine the diagnoses for this study, cardiologists not involved in the patients’ care reviewed all the participants’ relevant hospital records from the initial emergency visit through the 60-day follow up. In assigning the final diagnosis – either acute heart failure or some other cause for shortness of breath – these physicians also did not have access to the NT-proBNP results.

When they reviewed NT-proBNP levels, the researchers found that the protein’s concentrations were significantly higher in patients eventually diagnosed with heart failure and highest in those with most severe symptoms. For identifying heart failure in these emergency patients, the test alone was significantly more accurate than was the physicians’ original likelihood assessment, but a combination of NT-proBNP levels and physician judgement produced the most accurate method of diagnosis.

"We also identified specific NT-proBNP levels above which the diagnosis of heart failure is clear and below which the symptoms are definitely not cardiac-related," Januzzi says. "So we’ve shown that this test not only can confidently exclude the presence of congestive heart failure, which other studies have examined, but can confirm that diagnosis as well. NT-proBNP performed exceptionally well and confirms the value of the natriuretic peptide class of cardiac biomarkers as a whole. We believe NT-proBNP testing should now become a routine component of evaluation for patients with shortness of breath in emergency department settings." Januzzi is an assistant professor of Medicine at Harvard Medical School.

Co-authors of the study – all from the MGH – are Carlos Camargo, MD, PhD; Saif Anwaruddin, MD; Aaron Baggish, MD; Annabel Chen, MD; Daniel Krauser, MD; Roderick Tung, MD; Renee Cameron, MS; Tobias Nagurney, MD; Claudia Chae, MD, MPH; Donald Lloyd-Jones, MD, ScM; David Brown, MD; Stacy Foran-Melanson, MD, PhD; Patrick Sluss, MD, PhD; Elizabeth Lee-Lewandrowski, PhD, MPH; and Kent Lewandrowski, MD. The study was supported by a grant from Roche Diagnostics, which manufacturers the NT-proBNP assay studied.

Sue McGreevey | EurekAlert!
Further information:
http://www.mgh.harvard.edu

More articles from Health and Medicine:

nachricht Finnish research group discovers a new immune system regulator
23.02.2018 | University of Turku

nachricht Minimising risks of transplants
22.02.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

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: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>