Quantcast

Industry news that matters to you.  Learn more

Emerging Biomarkers Disrupt Cardiac Diagnostics

Even though brain natriuretic peptide (BNP)/pro-BNP and troponin biomarkers are the gold standard for the diagnosis of cardiac diseases, end users will soon see additional alternative biomarkers entering the market. By 2024, emerging biomarkers, such as ST2 Galectin-3, are becoming more sensitive in diagnosing cardiovascular disease will penetrate the lab-based and point-of-care (POC) end user segments.

Two Biomarkers Predict Increased Risk for “Silent” Strokes

Two biomarkers widely being investigated as predictors of heart and vascular disease appear to indicate risk for “silent” strokes and other causes of mild brain damage that present no symptoms, report researchers from The Methodist Hospital and several other institutions in an upcoming issue of Stroke (now online).

The researchers found high blood levels of troponin T and NT-proBNP were associated with as much as 3 and 3.5 times the amount of damaged brain tissue, respectively. The findings are part of the large-scale Atherosclerosis Risk in Communities (ARIC) study, funded by the National Heart, Lung, and Blood Institute.

“The concept of prevention is expanding,” said principal investigator Christie Ballantyne, M.D., director of the Center for Cardiovascular Disease Prevention at The Methodist Hospital. “It’s not good enough to simply do a few tests and try to assess risk for heart attack. What we need to do is assess the risk for heart attack, stroke, heart failure and also asymptomatic disease so we can start preventive efforts earlier. Waiting to correct problems until after a symptomatic stroke may be too late.”

One possible outcome is that patients determined to be in high-risk groups could be started on anti-stroke medications sooner.

In another ARIC paper published two months ago in Stroke, Ballantyne and coauthors reported a strong association between blood levels of troponin T and NT-proBNP and more severe instances of stroke, called symptomatic stroke. The current study looked at the two biomarkers and “subclinical,” asymptomatic events in the brain that are usually caused by a lack of blood flow.

“Taken together, these two papers show the biomarkers are effective at identifying people who are likely to have mild brain disease and stroke well before damage is done,” said Ballantyne, who also is a Baylor College of Medicine professor. “This hopefully will give doctors more time to help patients take corrective steps to protect their brains.”

For the subclinical brain disease study, researchers gleaned data from about 1,100 patient volunteers who agreed to have blood drawn and two MRI scans eleven years apart to look for silent brain infarcts and also white matter lesions (WMLs) caused by chronic inflammation.

Statistical analysis showed a strong relationship between high NTproBNP and the likelihood of brain infarcts and WMLs. Study participants with the highest levels of NT-proBNP had as much as 3.5 times the number of brain infarcts as participants with low NT-proBNP levels, and more WMLs. Those with the highest levels of troponin T had as much as 3.0 times the number of brain infarcts and more WMLs.

The protein troponin T is part of the troponin complex and its presence is often used to diagnose recent heart attacks. NT-proBNP is an inactive peptide fragment left over from the production of brain natiuretic peptide (BNP), a small neuropeptide hormone that has been shown to have value in diagnosing recent and ongoing congestive heart failure.

“The highly sensitive troponin T test we used is not approved for general clinical use in the US yet, but the NT-proBNP test is just now starting to be used more widely beyond making a diagnosis for heart failure,” Ballantyne said.

The Center for Cardiovascular Disease Prevention is part of the Methodist DeBakey Heart & Vascular Center.

Also contributing to this study were Razvan Dadu, Salim Virani, Vijay Nambi, and Ron Hoogeveen (Baylor College of Medicine and Methodist Center for Cardiovascular Disease Prevention), Myriam Fornage and Eric Boerwinkle (University of Texas Health Sciences Center at Houston), Alvaro Alonso (University of Minnesota School of Public Health), Rebecca Gottesman (Johns Hopkins School of Medicine), and Thomas Mosley (University of Mississippi Medical Center). It was funded with grants from NHLBI and NIH, while Roche Applied Science helped fund the development of diagnostic technology.

Stroke is published by the American Heart Association and American Stroke Association.

Source: Cardiovascular Biomarkers and Subclinical Brain Disease in the Atherosclerosis Risk in Communities Study.

Source: Troponin T, N-terminal pro-B-type natriuretic peptide, and incidence of stroke: the atherosclerosis risk in communities study.

Source: The Methodist Hospital System

Better Diagnosis of Acute Heart Failure Using Pronota’s Novel Biomarker

Two independent validation studies demonstrate that Pronota’s biomarker CD146 significantly improves the diagnosis of acute heart failure for patients with shortness of breath. The biomarker, measured in blood, provides clinicians with unique additional information allowing better treatment of this challenging group of patients.

Current diagnosis for acute heart failure is limited

Current clinical practice for triaging patients with shortness of breath includes the measurement of specific peptides (B-type natriuretic peptides: BNP or NT-proBNP). Despite the widespread use of these biomarkers, there is still much room for improvement. “Natriuretic peptides have become standard tools to support making the correct diagnosis in patients with shortness of breath. However, clinicians clearly recognize the limitations of natriuretic peptides. The potential value of another biomarker to improve the diagnostic accuracy of BNP or NT-proBNP is considerable,” commented Prof. J. Januzzi (Massachusetts General Hospital, Harvard Medical School).

Pronota’s novel heart failure marker for accurate diagnosis

Pronota identified the biomarker CD146 from an unbiased proteomics effort. Its performance has now been confirmed in two independent studies totaling over 500 patients. Prof. A. Mebazaa (INSERM, Paris, France), principal investigator for the validation studies, commented: “It is exciting to see that novel biomarkers with underlying biological processes completely different from currently used biomarkers can still be discovered and validated. This not only provides more insight into the underlying disease mechanism, it also gives the physician tools to improve the management and care of heart failure patients. Pronota’s approach in this respect is unique and has proven to deliver on numerous occasions.”

Launch forecast: 2014

“Data from early verification and marker characterization studies were already highly exciting, but the recent independent validation studies exceeded our expectations and would not have been possible without the support of our network of key opinion leaders in the field” commented Katleen Verleysen, CEO of Pronota NV. “We anticipate launching this product in 2014, so that clinicians may get access to the tools they need to improve the treatment and care of their patients.”

Source: Pronota

Pilot Study Demonstrates Home BNP Testing Is Feasible & Suggests Home Monitoring May Have Value in Guiding Therapy for High-Risk Patients

Alere Inc. (NYSE: ALR), a leading provider of near-patient diagnostics and health information solutions, recently announced the final results of the HABIT pilot study, which were recently published in the Journal of the American College of Cardiology. Led by Dr. Alan Maisel , Professor of Medicine at the University of California, San Diego, the study is the first to capture serial data from patients at high risk for recurrent acute clinical heart failure decompensation (ADHF), who performed a fingerstick BNP self-test from home for a period of 60 days. Results not only demonstrate that home BNP testing is safe and feasible for heart failure patients, but also indicate that BNP patterns following treatment for ADHF provide a wealth of information that may facilitate more personalized treatment leading to significant outcomes benefits.

In the United States, nearly one out of every four patients hospitalized for ADHF is rehospitalized within 30 days of discharge from the hospital, and the bulk of the costs associated with managing these patients derives from rehospitalization. Consensus among clinical experts is that more than 50% of hospital readmissions can be prevented through increased attention to modifiable factors that affect pulmonary congestion. But, while shortness of breath, edema, and weight gain can often signal pulmonary congestion, these symptoms may not appear in up to one-third of all heart failure patients. Changes in natriuretic peptide (NP) levels, along with monitoring for symptoms, signs, and weight changes, have been shown to improve the certainty of predicting heart failure decompensation. Up until now, however, NP measurements have been excluded from home heart failure monitoring programs because of the need for phlebotomy.

The HABIT study, a multi-center, single-arm, double-blinded observational prospective clinical trial, was designed to monitor daily concentrations of B-type natriuretic peptide (BNP) and determine the extent to which they correlate with ADHF and related adverse outcomes. A total of 163 patients with ADHF who were discharged from the hospital or being treated in an outpatient setting measured their weight and BNP levels daily for a period of 60 days using a fingerstick test run on the Alere™ Heart Check. Adverse outcomes for ADHF were measured as a composite of events that included cardiovascular death, admission for decompensated heart failure, or clinical heart failure decompensation requiring either parenteral therapy or adjustments to oral medications.

A total of 6,934 daily BNP values were recorded, with a median of 46 measures per patient over the course of the monitoring period. 40 patients had 56 events. Correlations between BNP measures weakened over time, and the dispersion between measures grew. When the monitoring period for each subject was broken into intervals based on ADHF events, there were 39 (18.4%) intervals of upward-trending BNP corresponding to a risk increase of 59.8% and 64 (30.2%) downward-trending intervals corresponding to a risk decline of 39.0%. There were also 94 (44.3%) intervals with one or more days of weight gain corresponding to an increased risk of 26.1%. Investigators concluded that daily weight monitoring is complementary to BNP measurement, but changes in BNP levels ultimately signaled larger shifts in risk, both upward and downward.

“Our results demonstrate that it is feasible and safe for heart failure patients to measure their results at home on a daily basis,” said Alan Maisel . “The incremental data from serial home measurements following an episode of ADHF appear to provide a novel means with which to identify those patients who are at highest risk of recurrent decompensation. The pattern or trend in BNP values may be used to identify when to correlate with a face-to-face clinical assessment or therapeutic intervention, or to guide therapy with specific medication changes without additional office visits.”

Investigators have determined that the results of the HABIT pilot study warrant an interventional trial to measure the extent to which home BNP testing impacts formal outcomes measures that include hospital readmissions. A study comparing today’s standard of care, which involves monitoring symptoms of heart failure and body weight changes following hospital discharge under the management of hospital-based outpatient heart failure clinics, to an algorithm that incorporates routine, home BNP measurements is set to commence before the end of 2013.

Study: Primary Results of the HABIT Trial (Heart Failure Assessment With BNP in the Home)

Source: PR Newswire

Clinical Advantages of Critical Diagnostics’ Cardiac Biomarker ST2 Featured In YouTube Video

Critical Diagnostics, makers of the Presage® ST2 Assay, recently announced that a six-minute videotape by Antoni Bayes-Genis, MD PhD., head of Cardiology Service at Hospital Germans Trias i Pujol, in Barcelona Spain discussing results of a study just completed on the use of biomarkers over conventional clinical assessments for risk stratification of heart failure patients has been posted on YouTube for immediate viewing.

The study followed 876 heart failure patients with a mean age of 70.3 years for a period of 40 months. During this follow up period, 311 patients died. Researchers compared 11 clinical variables, including age, sex, ischemic etiology of heart failure, left ventricular ejection fraction, New York Heart Association functional class, diabetes, renal function, beta blocker treatment, ace inhibitor treatment, sodium and hemoglobin biomarkers, which are routinely used to stratify heart failure risk against three biomarkers: NT-proBNP from Roche (OTC: RHHBY), high-sensitivity troponin T and Critical Diagnostics’ ST2.

The results from this recent study highlights the enduring clinical utility of ST2 despite being combined with the established and widely accepted cardiac biomarkers, like NTpro BNP, in medical practice. “The best results were obtained for ST2 and high-sensitivity troponin T,” notes Dr. Bayes-Genis, the primary investigator of the study. “Whenever we added NT-proBNP to these other two biomarkers, net reclassification improvement was reduced.”

Check out the video below.

“We are seeing strong adoption of ST2 by leading cardiologists who understand many of the limitations of utilizing natriuretic peptide markers like BNP and NT-proBNP in their practice,” states David Geliebter, CEO of Critical Diagnostics. “Natriuretic peptide markers certainly have their role in diagnosing heart failure, but fall short in guiding treatment of diseased patients. In study after study, ST2 has consistently demonstrated improved accuracy of patient prognosis over natriuretic peptide markers alone.

“Two of the biggest criticisms we hear about natriuretic peptide markers are that their levels don’t change or change too slowly, so their value as a serial marker for guiding treatment is questionable and, furthermore, that results are often skewed by other influencers such as age, gender, body mass index, atrial fibrillation, history of heart failure, anemia and impaired renal failure. By comparison, ST2 levels change rapidly in response to changes in the patient’s condition—sometimes within hours—thus helping physicians make informed decisions on an appropriate course of action to take and, if needed, to quickly adjust care, such as titrating medication. Moreover, unlike natriuretic peptide markers, ST2 levels are not adversely affected by the above-mentioned confounding factors.”

“Heart failure has become a growing public epidemic, with increasing incidence and prevalence,” Dr. Bayes-Genis stresses. “As a result, there is a need to understand risk factors and risk stratifiers, to better identify the patients that are going to have a better or a worse outcome. We now have a new generation of biomarkers, high-sensitivity troponin T and ST2, which are easily measurable in our routine practice, which provide additional information to stratify the prognosis of patients with heart failure.”

Source: Critical Diagnostics