Please note: The Presage® ST2 Assay is CE
Marked and received FDA clearance for use in risk
stratification of chronic heart failure patients. ST2 may
not be used for any other purpose. If you are reading this
outside of the US or Europe, please check with local regulatory
authorities to determine if ST2 is cleared for sale in your
country. If you have any questions, please contact Critical
HEART FAILURE AFFECTS
Some 6 million people in the U.S. have
heart failure. An estimated 600,000 new cases of heart failure
are diagnosed each year and the number of deaths from this
condition has more than doubled since 1979.1
Heart failure is responsible for 11
million physician visits each year, and more hospitalizations
than all forms of cancer combined.2 In fact, one-fifth of all hospitalizations
have a primary or secondary diagnosis of heart failure. Heart
failure is the number one reason people aged 65 or older are
With an aging population, the prevalence
of heart failure grows, as does the added burden placed on the
healthcare system. In 2012, some $40 billion was spent to treat
heart failure in the U.S.2
Using ST2 As Part of A Heart Failure
Patient Management Program
Cardiac biomarkers are substances that are
released into the bloodstream when the heart is damaged or
stressed. In patients with chronic heart failure, measurement
of these biomarkers is used to help risk stratify, to assess
treatment options, monitor progress, and guide in-hospital and
ST2 is one such biomarker. ST2 is a
soluble protein expressed by the heart in response to disease
or injury. ST2 levels change quickly in response to changes in
the patient’s condition, and when used in conjunction with
other clinical parameters, help physicians make informed
decisions on an appropriate course of action to take.
Numerous published studies have
demonstrated that the level of ST2 in blood can predict patient
outcomes. Measuring ST2 via a simple, non-invasive blood test
allows for the early identification of high-risk chronic heart
failure patients for re-hospitalization and mortality versus
those at lower risk.
ST2 By The
By utilizing Critical Diagnostic’s
Presage® ST2 Assay as part of a patient management program,
clinicians can be more precise in caring for people with
chronic heart failure. This may lead to halting or slowing down
the progression of the disease.
Additionally, ST2 levels are not adversely
affected by such confounding factors as age, gender, body mass
index, history of heart failure, anemia and impaired renal
failure. ST2 has a single cutpoint, removing any
guesswork, making clinical decisions easier.
In spite of all the advancements in
medicine, over one million Americans end up in hospital for
heart failure each year. More alarming still, one in four will
be re-admitted within 30 days of discharge and approximately
HALF will be readmitted within six months.
Newly-enacted US government regulations
are forcing increased emphasis on reducing these
rehospitalizations. As of 2012, hospitals with rates of
rehospitalization significantly higher than expected lose a
percentage of their Medicare reimbursement across the board,
beginning at 1% of total reimbursements—and an additional
percentage point in 2013 and again in 2014.
There are solutions, however. For
instance, intensive disease management programs have been
demonstrated to reduce 30-day rehospitalization and mortality
rates, and therefore improve outcomes while driving down
The Presage ST2 Assay from Critical
Diagnostics allows prognosis and risk stratification of these
chronic heart failure patients, which, in turn, provides an
essential element to disease management programs, enabling
physicians to select those patients who are identified as
requiring focused care.
Using ST2 as part of a patient management
program may potentially reduce 30-day rehospitalization
Q: What Is ST2?
A: ST2 is expressed by the heart in
response to disease or injury. ST2 levels change quickly in
response to changes in the patient’s condition, and when used
in conjunction with other clinical parameters, help physicians
make informed decisions on an appropriate course of action to
take. Critical Diagnostic’s Presage ST2 Assay is a simple blood
test that aids in risk assessment of chronic heart failure
Q: I understand that there is a standard
cutpoint of 35 ng/ml. If my patient is above or below that
cutpoint, what does that tell me?
A: We should preface this answer by saying
that the Presage ST2 Assay is cleared for use in risk
stratifying chronic heart failure patients. To answer the
question, then, by way of reference, the median normal
concentration for ST2 is 18 ng/ml, while concentrations greater
than 35 ng/ml are strongly indicative of increased risk of
hospitalization or death. Likewise, patients with ST2 levels
below the cutpoint are at decreased risk for hospitalization or
death. It is also important to appreciate that risk is not
dichotomous. The single cutpoint of 35 ng/ml is very
informative and provides valuable clinical insight, however
numerous publications show that risk of adverse events
increases as ST2 concentrations increase.
Q: What clinical studies have been done on
A: Numerous published studies involving
tens of thousands of subjects have demonstrated that the level
of ST2 in blood can best predict patient outcomes.
Q: Natriuretic peptides, such as BNP and
NTproBNP, are established biomarkers for heart failure. Please
explain the additional clinical benefit of ST2?
A: ST2 and natriuretic peptides (NPs) are
measures of separate and distinct biological processes. NP's
are markers of hemodynamic instability or myocyte stretch,
whereas, ST2 is a biomarker of disease progression and
fibrosis, is a powerful and clinically useful biomarker for
prognosis, and when used in conjunction has the potential to
help identify patients requiring focused care.
Q: Is ST2 affected by any confounding
A. ST2 is not affected by age,
gender, BMI, or impaired renal function.
Q: What if the NP I’m using is positive,
but the ST2 is negative, and vice versa?
A: ST2 and NPs reflect two distinct but
overlapping biological pathways, therefore they provide
independent and complementary feedback on the disease. As
studies have shown, in the case where either NP or ST2 are
elevated, it likely that the patient is progressing towards a
worsening condition, therefore standard of care coupled with
more aggressive treatment may be indicated. We should also add
that when the NP and ST2 levels are both low, it’s a strong
signal that the patient is improving, and where both are high,
the patient is at significant risk for worsening condition or
Q: Describe the relationship between ST2
A: Importantly, ST2 gives an early signal
for short-term events, functioning as a trigger for initial
fibrosis and the cascade of events leading to cardiac
remodeling. From published data Galectin-3, on the other hand,
is an intrinsic mediator of systemic fibrosis which includes
cardiac remodeling and is thought to reflect a later stage of
the disease process.
Q: How often should a heart failure
patient be tested for ST2?
A: There is currently no guideline for
frequency of testing. It depends on the severity of the
patient’s HF status. We recommend that a HF patient should be
tested every time they come in for an outpatient visit, and
more often if a patient is in advanced stages of heart failure
Q: There’s a lot of talk lately about the
high rates of rehospitalization of heart failure patients. What
role can ST2 play in lowering these readmissions?
A: Of the over one million Americans that
end up in hospital for heart failure each year, an alarming one
in four will be re-admitted within 30 days of discharge.
Newly-enacted US government regulations are forcing increased
emphasis on reducing these rehospitalizations. As of 2012,
hospitals with rates of rehospitalization significantly higher
than expected lose a percentage of their Medicare reimbursement
across the board, beginning at 1% of total reimbursements—and
an additional percentage point in 2013 and again 2014. The
Presage ST2 Assay from Critical Diagnostics, allows prognosis
and risk stratification, which, in turn, may provide an
essential element to disease management programs that provides
physicians with a means of identifying those patients with
chronic heart failure who are identified as requiring focused
Q: What is the format of the test?
A: Currently the only format of the test
is available on is an immunoassay, 96 well manual ELISA plate.
We have other formats in the pipeline including a point of care
test and an automated platform.
Q: Where can I get the Presage ST2 Assay
A: Currently the test is available at
several reference labs in the U.S. Click here for a list of preferred
laboratories. You can also purchase kits through Critical
- Heart Failure Society of
- American Heart Association and the
American Stroke Association
- 35 ng/ml.
- Framingham Heart Study. Moreover,
when galectin-3 values were adjusted for kidney function,
the association with incident heart failure was not
- White Paper report, The Presage
ST2 Assay is an Effective Tool to Reduce 30-Day Heart
Failure Hospital Readmissions, available here