We will start talking about stress tests and are they really that necessary
so as you remember the front page for that article in the Washington Post was titled Questions Grow
About the Need for Cardiac Stress Tests and it was published on June 13th for decades cardiac stress
tests have been the go-to test for detecting heart disease heart attacks happen when blood
flowed to the heart is suddenly interrupted by a clot not by a plaque once you begin to understand
that one fact then you begin to understand why stress tests don't really predict heart attacks
cardiologists treat heart attacks with medications and procedures stents do work if you're treating a
heart attack 90% of stents are done for plaque and they don't work they don't prevent a heart attack
the doctor remove a clot if you're having one in other words yet again it's not the plaque
it's the clot that causes the heart attack so for people who are not in the midst of a heart attack
but have a positive stress test the usual advice was to open up those narrowed arteries squeeze
out that plaque a little bit more and that again has been demonstrated with ORBITA trial COURAGE
trial ISCHEMIA trials multiple trials that's not doing the trick the idea seems logical if you have
blockage then spread it out open that up but again all of that logic is based on the assumption that
the plaque itself is slowly squeezing off the artery and that's not what's going on so this
has led to over 8 million nuclear stress tests per year to detect blockage and invasive procedures to
open and bypass those blockages in the past couple of months though many elective procedures have
really plummeted because of the hospital shutdown that concerns the risks associated with COVID if
stress tests were that important to protect your health to protect you from having a heart attack
you would think that those stress tests would have continued on now if you read this article in the
post again it's a physician he's very well aware of what's going on and he's making the point yes
some of this might just be the straw event for stress tests there is huge financial reasons that
the medical industrial complex continues to push stress tests despite the fact that the science
is becoming clearer and clearer that they don't do what we hoped they would do so you've got the
ORBITA trial you've got the COURAGE trial you've got these trials going on you've got docs looking
at decreased income what do you do well when something comes along like a pandemic maybe you go
ahead and make that change you see stress tests require 50% or more blockage to show a problem
68% of heart attacks occur in people with less than 50% percent blockage of flow this only leads to
false-negative results so you go in you've got a little bit of plaque it's not enough to block the
flow you do fine on it you go back out even though it was only a small amount of plaque that plaque
happened to be inflamed it leaks back out into the blood system causes that clot the clot releases
and stops blood flow to the heart and that's exactly what happened to Tim Russert I believe
it was Friday the 13th of June 2010 or 2011 30% of positive stress tests are false positives
false positive meaning like they're not going to have a heart attack false-positive stress tests
unnecessarily lead patients to the cath lab the invasive procedures that come from the cath lab
are expensive and uncomfortable and most of the time cardiologists will go ahead and have the
patient sign up to get a stent you know we're about to do the cath we're about to find out
if you have plaque while we're in there let's just go ahead and do the stent if I think we need
one and the patient signs off for it and again so there you begin to see how the stress test
takes the patient and the doctor down that pathway stress test cath lab angiogram
and then a stent plaque detected during cardiac catheterization is the reason stents are placed
while 90% of stents are placed to prevent a heart attack multiple studies have shown
that they don't do that they don't prevent heart attacks evidence indicates that opening
arteries is a preventive measure in people who are not experiencing a heart attack
doesn't produce the benefits in 1988 John Ambrose who was a cardiologist at Mount Sinai in New York
all the way that far back he and his colleagues found that heart attack often didn't occur
where the blockages had been severe they occurred in other places again once you begin to understand
the mechanism it becomes clear why he found that that was the truth in 2007 the COURAGE trial
reported the procedure to place a stent and unclog arteries failed to reduce the risk of death or
heart attacks or other events the COURAGE trial I think was reported in the New England Journal and
actually the day that they announced Tim Russert's death they talked about the courage trial in 2018
ORBITA study was done it was actually a sham procedure it was done in England the human
subjects reviews wouldn't let them do that in the United States what they actually did was they took
people where their docs had said look you've got the indications to have a stent but we're going to
do a randomized clinical trial they took them into the surgical room they prepped them for surgery
they even put them to sleep but only half of them actually got the stent the other half did not
guess what happened same amount of heart attacks whether you had the stent whether you didn't
now when I start talking about these studies I usually get a lot of haters coming in and saying
you can't tell me my stent didn't work I'm not telling you your stent doesn't work also I'm not
telling you that stents don't help for a heart attack if the stent is used to remove the clot
during a heart attack it absolutely helps but that's only 10% of stents another place where
stents can help would be they can often result in decreased significant or severe angina but 90% of
stents again are placed to prevent a heart attack they don't do that now in 2020 another trial was
done it up until that point they said well okay maybe stents don't prevent heart attacks but we
know that bypass surgery does CABG coronary artery bypass grafts 2020 I think again also New
England Journal ORBITA was in I think Lancet it was an English study 2020 again I think in the New
England Journal they looked at mostly bypass and they found the same thing bypass does not prevent
a heart attack so this is a little bit deeper into the ISCHEMIA trial again New England Journal 5,179
patients moderate to severe ischemia in other words restriction of blood flow to the tissues
in the heart randomly assigned to invasive strategy which included angiography going to
the cath lab revascularization when feasible in other words stent and or bypass or a much more
initial conservative strategy medical therapy alone angiography if the medical therapy failed
the outcome in terms of death from cardiovascular causes myocardial infarction or hospital
hospitalization from unstable angina heart failure or resuscitated cardiac arrest no difference
in any of those significant areas so the study put into the question how valuable are bypass grafts
how valuable are stents and therefore how valuable is the stress test because you get started down
this road by getting that stress test now again if you've got more interest in this topic in this
space that's what the book's about it'll be coming out again over the next four to eight weeks it
goes into all of the different ways of predicting heart attack measuring plaque the title of the
book is Prevention Myths Why a Stress Test Can't Predict a Heart Attack and What Other Tests Can so
COVID-19 this gets back to that last article from the Washington Post on June 13th how did
COVID affect all this the COVID pandemic is forced to change in practice at least for the past
few months some people have deferred needed tests but there are others whose tests may no longer be
useful in the midst of one of the most dramatic reversals of practice that we have seen in a
long time this may actually be an opportunity to improve clinical care there are still some reasons
for stress testing such as diagnosing angina but the ISCHEMIA trial should reduce the result the
use of treadmills and other tests hopefully they will never return to their prior level of use
and according to the Washington Post Harlan I'm blanking on his last name that would be a
good thing to come out of the epidemic and guess what I guess it's pretty clear I agree with him
hey test don't guess for 199 including labs we can get a full-blown
insulin survey like the Kraft insulin survey with oral glucose tolerance check it out