A RECENTLY published article in the New England Journal of Medicine alluded to a study that concluded, in essence, that intensive medical treatment had the same results as interventional therapy (angioplasty with stenting, or heart bypass) for those with angina (chest pains) from ischemia (lack of blood supply to heart muscles due to arterial blockages). There are subtleties and medical nuances to this which a lay person might not be able to discern.
This may have spread via the internet and could be causing some confusion and concern in the mind of the public, depriving patients from making the correct intelligent medical decision. Allow us to clarify the issue in layman’s term and put the facts in their proper medical perspective.
While an aggressive medical regimen of pills may succeed in relaxing coronary arteries that are in spasm (narrowing the lumen of the arterial channel) and allow some blood to go through, these vasodilators would not be able to open up obstructed arteries, which are stenosed (blocked by rock-hard calcium within these tiny arteries). I have broken scalpels (blades) in surgery trying to cut these solid stony blockages. They are like teeth, bones!
Arterial spasm is a physiological-biological reactive condition, which could respond to “anti-spasm/vasodilator” medications, but a calcified blockage inside the arteries, especially those obliterating the arterial channel more than 50 percent, will not dilate (open up) enough, thus still reducing the blood flow to the heart muscles. And if the blockage is 80 percent or complete, no medication could open it up. The analogy of a massive two-semi trucks accidents blocking three of a 4-lane highway can only be cleared by towing all the trucks blocking the expressway because they are a physical-mechanical obstruction. If the obstruction were caused by snow or fallen garbage on the highway, they could easily be power-washed, etc.
While that study had the usual noble goal of protecting the patients from any unnecessary procedure, it is short in practical scientific wisdom and lacks support from larger evidence-based studies, many authored by non-surgeons, which showed that for left main artery blockage and multi-vessel blockages (3 or more), which they usually are, coronary artery bypass in the long run benefits the patients the patients better, even compared to angioplasty and stenting, much less medical therapy alone, as far are morbidity and mortality are concerned. And there are countless millions of bypass patients around the world to prove this.
When a patient comes in with angina, a complete history and comprehensive physical examination and laboratory tests are done. If coronary heart disease is suspected, coronary angiography – cardiac catheterization is the definitive diagnostic procedure recommended.
What is a cardiac catheterization?
Cardiac or heart catheterization is a medical test where radio-opaque dye is injected into the left (and as needed, also into the right) chamber of the heart and the coronary arteries of the heart to find out if there are any abnormalities of the inner walls of the heart, the heart valves, the strength of the cardiac contraction (pumping action), and any blockages in heart arteries.
How is it performed?
The cardiologist injects an anesthetic agent (numbing medication) into an area of the skin in the groin of the patient, who has been given a sedative beforehand, and makes a 2 mm hole in the skin. Through this tiny opening, a catheter (size of a strand of spaghetti) is inserted into the femoral (groin) artery and under X-Ray fluoroscopic guidance, advances this catheter to the base of the ascending aorta (large major artery connected to the heart). The two main coronary arteries (left and right) branch out from the base of the aorta to supply blood (carrying oxygen and nutrition) to the muscles of the heart. Once the tip of the catheter catches or hugs the opening of the left and right coronary arteries, dye is injected into the catheter into these arteries, and video film of the dye flowing into the coronary arteries are taken. If there are any blockages, they will be captured on the (movie) film. Dye is also flushed into the left ventricle (in some cases, also into the right ventricle) to visualize any wall or valve abnormality and measure the Ejection Fraction (EF) (as a gauge of how powerful the left ventricle pumps blood into the circulation. A poor EF suggests weak cardiac muscles, which could be due to blockages of the coronary arteries (lack of blood supply), diseased heart valves or cardiomyopathy (usually a viral infection that causes weak and flabby heart muscles).
Why is this test important?
Cardiac Cath or Coronary Angio, as the procedure is popularly nicknamed, is what could be regarded as the “supreme court” of all heart tests. While EKG (electrocardiogram) and Stress EKG (treadmill test), or even ECHO (echocardiogram) are studies used to detect the presence of coronary artery disease, these tests are non-invasive procedures utilized as preliminary or screening diagnostic methods. If they show normal results, then chances are there are no blockages in the coronary arteries. If the results are doubtful or positive, then cardiac cath is performed to make the final determination. Following cardiac cath, the physician can say with practically 100% certainty if the patient has coronary blockages or heart valve disease or not. Hence, it is considered the “supreme court” or “court of final resort” of cardiac diagnostic tests.
Any death reported from the procedure?
Just like many invasive medical tests, cardiac cath has attendant risk, but the risk of dying from cardiac cath is much, much less compared to, say accidental death from a car accident on a busy highway. The risk of NOT having the test at all and leaving the heart condition undiagnosed poses a greater risk than undergoing cardiac cath. In one study, it was shown that in 5000 consecutive cardiac caths performed, there was no mortality at all. Indeed, cardiac cath is one of the safest tests, and a most valuable and life-saving one.
Should cardiac cath be done as preventive measure?
Not as a rule. If there are no symptoms, and the patient is healthy and active, we do not recommend cardiac cath just to satisfy our or the patient’s curiosity. Besides being expensive, the test has possible risk and complications (although mild and rare) as described earlier. One exception is for big corporation executive check-ups and for airline pilots, where some companies require initial employment cardiac cath. The other exception, which is more of a medically indication, is for persons who have a strong family history of heart attack (a genetic predisposition), and who are also hypertensive, diabetic, and a cigarette smoker.
Love and protect your heart; it’s the only one you’ve got, and can’t live without it.
Philip S. Chua, MD, FACS, FPCS, a Cardiac Surgeon Emeritus based in Northwest Indiana and Las Vegas, Nevada, is an international medical lecturer/author, and Chairman of the Filipino United Network-USA, a 501(c)3 humanitarian and anti-graft foundation in the United States. Visit our websites: philipSchua.com and FUN8888.com Email: [email protected]