Heart Disease is #1
killer of women, could a simple test be a lifesaver?
Newswise — New research
from Saint Louis University School of Medicine may give
doctors a way to predict life-threatening heart problems in
The team studied 421
diabetic women between 49 and 75 who underwent a certain
type of stress test for suspected coronary disease.
Investigators concluded that the test, known as dobutamine
stress echocardiography, provided valuable information that
could help doctors predict future fatal heart problems.
“Our research is extremely
important, because women in this age group are historically
underdiagnosed, and by detecting problems earlier, we can
help prevent heart attack or death and extend these women’s
lives,” says Melda S. Dolan, M.D., associate professor in
the division of cardiology at Saint Louis University School
Dolan will present two
papers during the annual American Heart Association meeting
in Dallas on Wednesday. Both papers explore the role of the
stress tests in detecting heart disease.
echocardiography tests are ultrasound heart scans in which
patients are injected with a drug that makes the heart beat
faster to determine if they have abnormalities of the heart
wall. No exercise is involved. Traditional echocardiography
tests are performed without the aid of drugs by having
patients run on a treadmill to increase their heart rate.
“Women with diabetes and
other clinical risk factors, such as smoking, obesity and a
family history, are more likely to have heart disease or die
from it,” says Dolan. “Dobutamine stress echo tests serve an
important role in predicting heart attacks or cardiac death
in these higher-risk women.”
After two years, the team
followed up with the patients and found that 23 had died
from cardiac events and 54 had experienced heart attack.
While history of congestive heart failure and previous heart
attacks were clinical predictors in those cases, the
dobutamine stress echo tests were also beneficial in
predicting them, Dolan says.
“The rate at which the
patients experienced cardiac death or heart attacks was
higher in patients with positive stress tests for ischemia –
a decreased supply of blood to the heart – than in those who
had negative tests,” Dolan says.
In a second study, Dolan
and other SLU researchers studied 1,404 patients who
underwent preoperative dobutamine stress echocardiography to
determine if they had ischemia.
“In the medical community,
it is common to believe the heart rate must be at least 85
percent of the maximal heart rate,” Dolan says. “However, we
found that a negative dobutamine stress test without
abnormalities has a very strong negative predictive value –
that is, that patients test negative for ischemia – whether
the heart rate is maximal or not.”
The implications for such
results are that doctors ordering stress echocardiography
can have more confidence in tests returning negative for
ischemia than they had previously thought, effectively
broadening the parameters normally used to rule out ischemia
– meaning some patients will not have to undergo additional
heart scans to rule out the condition before they undergo
Co-authors of the studies
are Swathy Kolli, M.D.; Michelle Bierig, RDCS; Jeannette A.
St. Vrain, RDCS; Bernard Chaitman, M.D.; and Arthur Labovitz,
M.D., director of the division of cardiology at Saint Louis
University School of Medicine.
Established in 1836, Saint
Louis University School of Medicine has the distinction of
awarding the first M.D. degree west of the Mississippi
River. Saint Louis University School of Medicine is a
pioneer in geriatric medicine, organ transplantation,
chronic disease prevention, cardiovascular disease,
neurosciences and vaccine research, among others. The School
of Medicine trains physicians and biomedical scientists,
conducts medical research, and provides health services on a
local, national and international level.