How Long Are Stress Tests Results Valuable?

[jerry78]

I have read different literature pertaining to how quickly a coronary artery can block, and some medical journals state an artery can go from 0 % to 90 % in a matter of weeks.

If this is the case, then a normal stress test would only be reassuring for, perhaps, a month or so.

Any truth to this research?

[Cleveland Clinic]

Jerry,

What erik is referring to is what happens with a plaque rupture. In this setting the surface of the cholesterol plaque ruptures and exposes its contents to the blood stream causing a blood clot to form ontop of the plauqe.  Thus, technically the plaque can go to 100% occlusion rapidly. The growth of an atherosclerotic plaque outside of this phenomena is quite different.

In the recent REVERSAL study performed at the Cleveland Clinic, following stenosis of patients taking statin medications, there was a 2.7% increase in patients taking simvistatin and a 0.4% increase in patients taking high dose atorvastatin. The overall consensus of this study was that high dose statin therapy can halt or slow the progression of obstructive coronary disease.

In the absence of symptoms, usually we will repeat a stress in patients with known disease.

Markers of arterial inflammation such as CRP can help identify patients whose disease might be active and who need more intensive monitoring and therapy.

good luck

[Dr. Erik]

A coronary artery can go from 0% to 100% in a matter of seconds. All it takes is for a piece of unstable plaque to break off somewhere and block an artery causing a heart attack. That's why one should exercise and keep their cholesterol numbers normal. one thing that leads to heart attacks is an elevated CRP level in the blood. It is a marker for inflamation (inflammation) in the body and can make plaque unstable. Ways to keep CRP levels low is exercise, take a Statin drug if necessary and a moderate amount of alcohol,1 drink a day. If you don't already drink, don't start.

[3rdMajor]

Hi Jerry,
    A stress test shows that your heart is able function at a certain level.  From a negative stress test, one might conclude that there is no "Major Blockage" of coronary arteries.
A major blockage would probably be 70% or greater.
Blockages that are 70% or greater, begin to restrict the blood flow to the heart under stress, and should be caught by a stress EKG.  About this same time, these blockages begin to be symptomatic with angina.  I was asymptomatic on a resting EKG in June, and underwent quintuple bypass surgery in December.  This does not mean I went from 0% to 90+% in 6 months.
Typically, it is not the large, stable blockages that are involved in heart attacks. The large blockages tend to cause angina, and limit activity.  It is the relatively new and soft placques of 20-30% that rupture and cause coronoary thrombosis.  In other words, it is the blockages that are not synmptomatic, and are not revealed by traditional diagnostic measures, that are usually implicated in infarction.

[jerry78]

As you both have indicated, concernig small, undiagnostic, asymptomatic, plaques are the most likely culprits, as was in your case 3rdmajor, then I see no use in even obtaining diagnostic tests such as exercise stress tests......
What good are they if they can only reveal blockages of 70 % or more, and as you said, its the soft plaques that usually cause the problems.....so, a normal, negative stress test really means nothing in the face of a possible cardiac event in the near future.

[raildown]

a treadmill stress test should be part of a arger workup and risk factor analysis w.r.t. coronary artery disease;

note hat treadmill stress tests have a troubling level offalse positives adfalsenegatives ;

nuclear/radiologic cardiac perfusion (blood flow to heart muscle) tests such as thallium or PET scans show how well the heart muscle actually receives blood flow;

notwithstanding the problems with treadmill stress tests, studies show that a higer level of fitness positively effects functionality and longevity in cardiac syndromes;

//