Heart Failure Study Performed By Cleveland Clinic Shows Serial Testing With Cardiac Biomarker ST2 Predicts Outcomes Of Hospitalized Patients

SAN DIEGO--(BUSINESS WIRE)--Critical Diagnostics reported today that an abstract, “Prognostic Value of Baseline and Changes in Circulating Soluble ST2 Levels and the Effects of Nesiritide in Acute Decompensated Heart Failure,” presented at the American College of Cardiology Scientific Sessions in San Diego over the weekend demonstrated in hospitalized heart failure patients that elevated levels of the cardiac biomarker ST2 were associated with an increased risk of adverse events. Authors include W.H. Wilson Tang of Cleveland Clinic, and Michael Felker and Christopher O’Connor of Duke University Medical Center and Duke Clinical Research Institute,

“Are Biomarkers the Answer to the Heart Failure Readmissions Problem?”

Part of a large multinational, multi-center, prospective randomized study (ASCEND-HF) of hospitalized patients with acute decompensated heart failure, this 858-patient cohort showed higher levels of ST2 were associated with increased risk of death. Moreover, patients whose ST2 levels failed to drop within 48 to 72 hours were more than two-and-a-half times as likely to die, compared to those whose ST2 levels dropped.

About 1.1 million heart failure patients will be discharged from hospital in the U.S. this year. In fact, heart failure is the leading cause of hospitalization in people over 65 years of age. However, almost one quarter of these discharged heart failure patients will be rehospitalized within 30 days of discharge, with an average cost per patient for rehospitalization of $22,700. Front and center are Centers for Medicare and Medicaid’s regulations on preventable readmissions. Under the Act, hospitals with rates of rehospitalization significantly higher than expected lose 3% of their Medicare reimbursement across the board, meaning ALL Medicare reimbursements, not just for heart failure.

When implemented correctly, though, intensive disease management programs have been demonstrated to reduce 30-day rehospitalization and mortality rates, but correct identification of those most likely to benefit from such intervention is challenging. Consequently broadly implemented disease management programs have not provided a cost effective reduction in rehospitalization rates. Since hospitals don’t have the ability to monitor all discharged patients – this would overburden staffs and obliterate budgets -- using ST2 allows for the risk stratification of these patients, thus enabling more focused management for those that need it most, while keeping costs in check.

“This Cleveland Clinic study corroborates what a number of other studies have conclusively shown,” remarks David Geliebter, CEO of Critical Diagnostics, “namely that ST2 can be a valuable tool in reducing heart failure re-hospitalization and death.”

A 2013 study (“Heart Failure Therapy Induced Early ST2 Changes May Offer Long-term Therapy Guidance,” Journal of Cardiac Failure) from Basel Switzerland and Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, demonstrated ST2 values accurately predict heart failure event risk in hospitalized heart failure patients. Levels of ST2 were measured at presentation to the emergency department and after 48 hours in 207 patients with acute heart failure. In univariate analysis the percentage change of ST2 over the first 48 hours significantly predicted long-term mortality.

In multivariable analysis, the predictive potential of early ST2 changes persisted after the adjustment for ADHERE risk factors (blood urea nitrogen, systolic blood-pressure and serum creatinine), traditional markers of inflammation (total white cell count and high- sensitive C-reactive protein), BNP, troponin T, percentage BNP changes during the first 48 hours as well as the cumulative diuretic dose administered during the first 48 hours.

Drs. Shannon M. Dunlay and Allan S. Jaffe of Mayo Clinic, published a paper in 2013 in Clinical Chemistry, titled, “Are Biomarkers the Answer to the Heart Failure Readmissions Problem?” In it, ST2 was declared to be “the most potent predictor of rehospitalization of all biomarkers assessed.” And, notably, it demonstrated that serial changes in ST2 were superior to both BNP and troponin — the two most-often used cardiac biomarkers — in the prediction of adverse events in otherwise stable chronic heart failure patients.

As the paper pointed out, the use of BNP was “no better than a flip of a coin” in predicting hospital readmissions, and therefore was no help in addressing this healthcare dilemma. Furthermore, the wide biological variation of BNP, which is affected by such confounding factors as age, body mass index, renal failure, smoking and other comorbidities common to heart failure patients, means “marked changes are necessary with BNP measures to be sure they are not simply due to spontaneous variation.” ST2 is not affected by these confounding factors.

In another paper published last year by Drs. Lori Daniels and Tony Bayes-Genis titled, “Using ST2 in Cardiovascular Patients: A Review” in Future Cardiology, a specific recommendation made is that “serial ST2 levels can be used to identify ‘ST2 nonresponders,’ or individuals whose ST2 levels fail to drop at least 15–25% within 2 weeks after an acute heart failure exacerbation. Such individuals are at increased risk for adverse outcomes.”

“These studies clearly show that the change in ST2 values over the first 48 hours of acute heart failure hospitalization reflect the patients’ prognosis and response to therapy,” noted James Snider, Ph.D., President of Critical Diagnostics. “Importantly, then, it demonstrates that risk can be attenuated.”

About Heart Failure

Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. As noted by Professor Eugene Braunwald in “The War Against Heart Failure,” in The Lancet,¹ Heart failure is a global problem with an estimated prevalence of 38 million patients worldwide, and a number that is increasing with the aging of the population. Heart failure is the most common diagnosis in patients aged 65 years or older admitted to hospital. Despite some progress, the prognosis of heart failure is worse than that of most cancers.

About ST2

ST2 is a soluble protein expressed by the heart in response to disease or injury. It is reflective of ventricular remodeling and cardiac fibrosis associated with heart failure. ST2 is not adversely affected by confounding factors such as age, body mass index and impaired renal function. Unlike many other cardiac biomarkers, ST2 levels change quickly in response to changes in the patient’s condition—thus helping physicians make informed decisions on an appropriate course of action to take and, if needed, to quickly adjust treatment. Since 2013 there have been over 400 scientific papers and abstracts published on ST2².

About Critical Diagnostics

Critical Diagnostics (www.criticaldiagnostics.com) develops novel biomarkers to help physicians optimize patient care in cardiovascular diseases, while containing healthcare costs.

¹ Published online November 16, 2014

² Based on PubMed.com listings.