BROOKLYN, N.Y., Nov. 16, 2019 /PRNewswire/ -- A federally
funded, international study found no evidence that patients with
severe but stable heart disease who underwent heart procedures
experienced lower rates of major, disease-related events compared
to those treated with medications and lifestyle changes alone.
Presented November 16 at the
American Heart Association's Scientific Sessions 2019, the study
found that patients that underwent routine, invasive procedures –
like stent implants or bypass surgery – when compared with patients
that received only medications (e.g. aspirin, statins) and
lifestyle advice, saw no reduction in the rate of occurrence for a
group of five events: cardiovascular death, heart attack,
hospitalization for unstable angina, hospitalization for heart
failure, or resuscitation after cardiac arrest.
Called ISCHEMIA (International Study of Comparative Health
Effectiveness with Medical and Invasive Approaches), the trial also
found no overall difference between the two treatment strategies in
the rates of cardiovascular death or heart attack.
At the same time, the investigators found that for patients
overall with symptoms of angina – the chest pain caused by
restricted blood flow to heart muscle – invasive treatments
resulted in better symptom relief and quality of life that
persisted for four years. Among those with daily or weekly angina
at the start of the study, 50 percent of those treated invasively
were angina- free after a year, compared to 20 percent of those
treated with medications and lifestyle advice alone.
Both patient groups in the study received "optimal medical
therapy" (OMT), the term for medications and lifestyle advice, with
one group undergoing invasive procedures soon after having an
abnormal stress test, and the other treated invasively only if
symptoms worsened despite drug therapy, or in the case of an
emergency (heart attack). The several forms of stress test used in
the study, by making the heart work harder, determined the degree
of blood flow restriction (ischemia) in patients' coronary
arteries.
Led by researchers at NYU Grossman School of Medicine and
Stanford University, with data
management and statistics led by the Duke Clinical Research
Institute (DCRI), the study randomly assigned 5,179 patients at 320
sites in 37 countries to receive one of the two treatment
strategies, making it more than twice as large as any
previous study of its kind. The quality of life component was led
by researchers at Saint Luke's Mid America Heart Institute and
DCRI.
"In line with evidence from prior studies, our results suggest
that routine use of heart procedures was not superior in reducing
risk for the five-part disease endpoint or death overall compared
to treatment only with optimal medical therapy," says ISCHEMIA
study chair Judith Hochman, MD, the
Harold Snyder Family Professor of Medicine and Senior Associate
Dean for Clinical Sciences, at NYU Langone Health. "On the other
hand, patients symptomatic to start that got heart procedures, over
the years, had fewer symptoms and felt better."
Study Details
Funded by the National Heart, Lung, and
Blood Institute, ISCHEMIA studied patients with stable ischemic
heart disease (SIHD), which occurs when not enough oxygen-rich
blood is supplied to heart muscle. The "vast majority" of patients
in the study were determined to have moderate or severe ischemia
caused by atherosclerosis, cholesterol deposits that narrow
arteries. Ischemic heart disease (IHD) affects 17.6 million
Americans, resulting in about 450,000 deaths annually.
For the study, "invasive" treatment meant routine
catheterization, a procedure that slips a tube-like catheter into
an artery in the groin or arm, and threads it through blood vessels
to the heart. This was followed by revascularization when suitable
– in most cases involving delivery of a balloon through the
catheter to open a vessel (angioplasty), followed by the placement
of a rigid stent. In other cases, improved blood flow was
accomplished by cardiac bypass surgery, where another artery or a
vein is used to go around (bypass) the area of blockage.
The study design reflects clinical practice, where patients with
abnormal stress tests often undergo an angiogram and
revascularization, with a stent implant or bypass surgery. These
procedures are termed invasive because they are complex, with risks
of their own that include procedure-related death, heart attack, or
stroke, researchers say.
The rate of procedure-related stroke and death was "extremely"
low in ISCHEMIA, but the risk of heart attacks related to
procedures may explain, says Hochman, why those that had an
invasive procedure had a rate of events higher by two percentage
points over the first year than those that received optimal medical
therapy alone (5.3 percent with invasive vs. 3.4 percent for the
five-part endpoint).
By year two, the event rate for the study disease endpoints was
roughly the same between the two approaches (9 percent vs. 9.5
percent). By four years, the rate of events was two percentage
points lower in patients treated with heart procedures than in
those that received medications and lifestyle advice alone (13.3
percent with invasive vs. 15.5 percent). Overall, say the
investigators, the trend shifts over time showed no significant
evidence of a difference in rates between strategies.
Lastly, the team was surprised to see that the overall rate of
heart-related events over the duration of the ISCHEMIA trial was
lower than projected ten years ago. This is a testament, say the
investigators, to recent advances in drug therapies and
revascularization techniques.
"Based on our results, we recommend that all patients take
medications proven to reduce the risk of a heart attack, be
physically active, eat a healthy diet, and quit smoking," says
ISCHEMIA co-chair David Maron, MD,
Director of Preventive Cardiology and the Stanford Prevention
Research Center at Stanford University.
"Patients without angina will not see an improvement, but those
with angina of any severity will tend to have a greater, lasting
improvement in quality of life if they have an invasive heart
procedure. They should talk with their physicians to decide whether
to undergo revascularization."
Moving forward, the research team plans to follow the study
patients for another five years, to determine whether either
strategy is associated with better survival over a longer
observation period.
The study was approved by the NYU Grossman School of Medicine
institutional review board on March 29,
2012, with participants required to provide written consent
prior to enrollment. Made possible through significant
contributions by academic medical centers across the United States and globally, ISCHEMIA will
be presented at the session titled LBS.02 – Late breaking Science
II: Results for the Ischemia Trials: To Intervene or Not to
Intervene – on Saturday, November 16,
2019. The session will run from 2:00
PM - 3:15 PM in Main Event I at the AHA Scientific Sessions
2019, Pennsylvania Convention
Center Grand Hall, Philadelphia,
PA.
Media Inquiries – Rob Magyar –
robert.magyar@nyulangone.org – O – 212.404.3591 - C –
646.734.9653
View original content to download
multimedia:http://www.prnewswire.com/news-releases/ischemia-trial-finds-no-evidence-of-lower-cardiac-event-rates-in-patients-treated-with-heart-procedures-but-better-quality-of-life-300959573.html
SOURCE NYU Langone Health