Artery Blockage Not Necessary to Significantly
Increase Heart Attack Danger from Plaque
Evidence seems to indicate that non-obstructive
plaques can still rupture and case heart attack, i.e., plaque is
5, 2014 - Non-obstructive coronary artery disease was associated with a
28 to 44 percent increased risk of a major adverse cardiac event such as
a heart attack or death, in a new study presented yesterday at the
American Heart Association’s Quality of Care and Outcomes Research 2014
The rates of heart attack and death within one year
following angiography increased progressively with increasing coronary
artery disease (CAD) severity, even among those patients with
non-obstructive CAD, researchers found.
In this study, researchers studied 40,872 veterans
who underwent elective cardiac angiography from October 2007 to
September 2012. The patients’ condition was categorized as normal,
non-obstructive and obstructive CAD.
“Unlike obstructive CAD, which blocks blood flow,
non-obstructive CAD may initially appear less threatening on angiography
tests, but it appears to have significant risk for heart attack and
death” said Thomas M. Maddox, M.D., M.Sc., the study’s lead researcher,
a cardiologist for the VA Eastern Colorado Health Care System and
associate professor of medicine at the University of Colorado School of
Medicine in Denver.
“Dismissing non-obstructive CAD as harmless could
be dangerous. Our findings show there is indeed a risk, that
non-obstructive damage can lead to heart attacks just like obstructive
disease, and that we should consider preventive therapies for these
A similar study published in March of this year
supports these findings. The researchers in this study concluded, “Our
findings suggest that regardless of whether obstructive or
nonobstructive disease is present, the extent of plaque detected by
coronary computed tomography angiography enhances risk assessment.”
Patients with non-obstructive disease should ask
their physicians about preventative therapies, like quitting smoking,
healthy diets, getting enough exercise, losing weight and taking
preventative medications such as aspirin and statins.
Co-authors are Maggie Stanislawski, M.S.; Gary
Grunwald, Ph.D.; Steven Bradley, M.D., M,P,H,; Manesh Patel, M.D.;
Amneet Sandhu, M.D.; David Magid, M.D., M.P.H.; Benjamin Leon, B.S.;
Deepak L. Bhatt, M.D.; Stephen Fihn, M.D., M.P.H.; and John Rumsfeld,
M.D., Ph.D. Author disclosures are on the abstract.
The Department of Veterans Affairs funded the
What Is Coronary Angiography?
Coronary angiography (an-jee-OG-rah-fee) is a test
that uses dye and special x rays to show the insides of your coronary
arteries. The coronary arteries supply oxygen-rich blood to your heart.
A waxy substance called plaque (plak) can build up
inside the coronary arteries. The buildup of plaque in the coronary
arteries is called
coronary heart disease (CHD).
Over time, plaque can harden or rupture (break
open). Hardened plaque narrows the coronary arteries and reduces the
flow of oxygen-rich blood to the heart. This can cause chest pain or
discomfort called angina
(an-JI-nuh or AN-juh-nuh).
If the plaque ruptures, a blood clot can form on
its surface. A large blood clot can mostly or completely block blood
flow through a coronary artery. This is the most common cause of a heart
attack. Over time, ruptured plaque also hardens and narrows the
During coronary angiography, special dye is
released into the bloodstream. The dye makes the coronary arteries
visible on x-ray pictures. This helps doctors see blockages in the
For this procedure, a thin, flexible tube called a
catheter is put into a blood vessel in your arm, groin (upper thigh), or
neck. The tube is threaded into your coronary arteries, and the dye is
released into your bloodstream. X-ray pictures are taken while the dye
is flowing through the coronary arteries.
Cardiologists (heart specialists) usually do
cardiac catheterization in a hospital. You're awake during the
procedure, and it causes little or no pain. However, you may feel some
soreness in the blood vessel where the catheter was inserted.