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LATEST MORBIDITY
AND
MORTALITY STATISTICS
ON BYPASS SURGERY
AND
ANGIOPLASTY

Excerpts from Living Longer With Heart Disease:
The Noninvasive Approach That Will Save Your Life


With the exception of the first report in the next paragraph, the following series of reports are presented in chronological order. A common method of describing results is either mortality or freedom from a cardiovascular event such as death, heart attack, stroke or repeat bypass surgery or angioplasty. Mortality figures are presented in a variety of formats such as 3, 5, and 10 year mortality, and so are cardiovascular events. I have modified these figures so that they are on a yearly basis to make comparison easier. The first report (reference 17) is presented out of order because it not only shows the most recent statistics, but it also reflects outcomes in one of the largest group of patients to date.

From a multicenter study (17) from several major medical centers, using New York State's registry for patients undergoing coronary artery bypass surgery or coronary angioplasty, the mortality rate was tabulated for each procedure. I have listed separately the mortality rate on an annual basis for patients with disease involving two coronary arteries, and for patients with disease of all three coronary arteries. Keep in mind that the annual mortality for patients with two and three vessel disease who are treated conservatively with appropriate medication is less than 1% per year.

In 17, 857 patients with disease of all three coronary arteries who underwent coronary artery bypass surgery, the annual mortality rate was 3.3 %. In 1,294 patients with three vessel disease who underwent coronary angioplasty the annual mortality rate was 4.2 %.

In 9,212 patients with two vessel disease undergoing coronary artery bypass surgery, the annual mortality rate was 2.7 %. In 7,405 patients with two vessel disease undergoing coronary angioplasty the annual mortality rate was 2.3 %.

For mortality related to age, see the National Medicare Experience below.

Dr. Salem Yusuf reviewed the medical literature from 1972 to 1984 and compared the mortality of medical and surgical treatment. (18) There were four studies involving a total of 416 patients. At 10 years the mortality of the surgically treated patients was 33% or 3.3% per year. The mortality of the medically treated patients at 10 years was 34% or 3.4% per year. It is to be noted that this reflects the medical treatment primarily of the Seventies.

Dr. Spencer King of Emory University compared 194 bypass surgery patients with 198 angioplasty patients. The annual mortality for the bypass surgery patients was 2.1% per year and that for the angioplasty patients 2.4% per year. (19)

In a study of mortality rates in different age groups in Medicare patients undergoing either bypass surgery or angioplasty, Dr. Eric Peterson and his associates at Duke University Medical Center found the following. (20)

THE NATIONAL MEDICARE EXPERIENCE

  Mortality After Angioplasty
225,915 patients
  Mortality After Bypass Surgery
357,885 patients
Ages 30 Day 1 Year
     
30 Day 1 Year
  % %   % %
 
65-69 2.1 5.2   4.3 8.0
70-74 3.0 7.3   5.7 10.9
75-79 4.6 10.9   7.4 14.2
>80 7.8 17.3   10.6 19.5

Obviously, mortality rate is related to age. Unfortunately, rarely are these figures quoted to elderly patients when they are urged to undergo these procedures.

In a study of 591 patients from nine medical centers in North America, the in-hospital complication rate was Death 1.5%, Heart Attack 4.2%, Emergency Bypass 3.2% and Total Complications 15.4%. (21) This does not include complication rates after discharge from the hospital.

From the University of Washington in Seattle comes a study of the 15 year survival rate of the Coronary Artery Surgery Study of 6,018 men and 1,095 women who originally underwent treatment between 1974 and 1979. For medical treatment the 15 year survival rate for men was 50% and 49% for women. For those with initial surgical treatment the survival for men was 52% and 48% for women. Thus, there was no significant difference in survival between the two treatments with the annual mortality being 3.3%.

Another interesting study was the CAVEAT Trial (Coronary Angioplasty Versus Excisional Atherectomy Trial).(23) Atherectomy refers to the use of a rotor rooter type of device that is inserted into a coronary artery and the arteriosclerotic plaque is cut up and scooped out. In this study only the frequency of a myocardial infarction (heart attack) was studied in 500 patients undergoing angioplasty and 512 having atherectomy. The incidence of myocardial infarction in the atherectomy patients was 15.2% and it was 6.8 % in the angioplasty patients. The high incidence of heart attacks with both groups was because cardiac enzymes were measured rather than merely getting an electrocardiogram after the procedure. Thus, the reported incidence of myocardial infarction after these procedures is artificially low because insensitive methods of detection are being used.

Another report dealing with mortality rate in elderly patients undergoing cardiac surgery is from Cedars-Sinai Medical Center in Los Angeles. (24) In a study of 528 patients over 80, the 30 day mortality was 8.3%. At one year it was 18% and at 5 years 38%. These figures are very similar to the Duke study.

From the St. Louis University Health Sciences Center (25) a review of 250 patients undergoing coronary artery bypass surgery found that the annual mortality for patients between 60 and 79 was about 7% per year and for patients above the age of 80 it was 13% per year.

From the National Registry of Myocardial Infarction in 3,648 patients undergoing angioplasty who had this procedure done initially as the primary treatment, the in-hospital mortality for patients who were treated under one hour was 6.9%, from 1-2 hours 5.7%, from 2-3 hours 9.1%, and after three hours 9.4%. (26) These are not small numbers. In my experience the mortality rate of a heart attack patient after he or she reaches the hospital is excellent. There is a better than 95% chance of recovery, even better if the patient gets to the hospital early. Thus, the mortality rate for patients treated with angioplasty in this study is twice as great as with conservative medical treatment. A recent Veterans Administration Study showed similar findings in a group of 500 patients with an acute heart attack. There were 21 patients who died in the surgery or angioplasty treated group at nine days, but only six patients who died in the medically treated group in this time period.

Looking at mortality figures alone doesn't tell the complete story. Perhaps a better way to evaluate the outcome of these procedures is to combine all cardiovascular events including death on an annual basis. It is known, for example, the after angioplasty, the coronary artery that was dilated will usually become narrowed again and may close off. The frequency with which this happens is about 50%. How often this will result in repeat symptoms is not precisely known. The following reports describes recurrences of cardiovascular events including death, heart attack, unstable angina, repeat angioplasty and coronary artery bypass surgery.

From the Massachusetts General Hospital in a trial of 127 patients undergoing angioplasty or coronary artery bypass surgery, the annual cardiovascular event rate was 7.7% per year for the surgery patients and 17.7% per year for angioplasty patients. (27)

From the Thoraxcenter at Erasmus University in Rotterdam, a 10 year study of 856 patients undergoing angioplasty revealed an annual mortality rate of 2.2% and an annual cardiovascular event rate of 8.6%. (28)

In the BARI trial (Bypass Angioplasty Revascularization Investigation), 1,829 patients were followed for 5.4 years. (29) Annual mortality was 2.1% per year for bypass surgery and 2.7% per year for angioplasty. Event rate was 4% per year for surgery and 4.3% per year for angioplasty.

In a 10 year study from St. Antonius Hospital in the Netherlands, 351 patients who had angioplasty were followed.(30) Annual mortality was 2% per year and cardiovascular event rate 10% per year.

From the University of North Carolina at Greensboro, 633 patients who were treated with primary angioplasty for their heart attack were followed for 5.3 years. The in-hospital mortality was very high at 9% and the cardiac mortality at five years was another 9%.(31) Total mortality was twice what it should have been.

From the University of Ottawa Heart Institute in Ontario, Canada, a 25 year study of 1,388 patients who underwent bypass surgery at an average age of only 48 years reveals an annual mortality of 2%. Eighteen percent had to undergo repeat surgery during this period. (32)

From the Veterans Affairs Medical Center and the University of Colorado Health Sciences Center in Denver comes a study of 131 patients above the age of 70 with unstable angina who underwent coronary angioplasty for their symptoms. The mortality at 30 days was a striking 13%. (33)

In a comparison of medical treatment versus angioplasty for patients with stable coronary artery disease, 20 centers from the United Kingdom and Ireland treated 1,018 patients. The risk of death or a heart attack was 2.3% per year for angioplasty treated patients but only 1.2% per year for medically treated patients. (34)

In a recent Veterans Administration study known as the VANQWISH trial 920 patients from 15 medical centers with an acute heart attack were randomized to treatment with revascularization (angioplasty or coronary artery bypass surgery) or conservative medical treatment. At the time of discharge from the hospital, 21 patients who had undergone revascularization had died versus only six medically treated patients. At 2.5 years there were 80 deaths in the aggressively treated group versus only 59 deaths in the conservatively treated patients.

There are only a few reports dealing with the use of stents placed within a coronary artery. A stent is a metal tube that can be expanded when placed within a coronary artery. When fully expanded it becomes a scaffolding that helps to keep the artery from closing. Typically, when an artery is dilated with balloon angioplasty, a delayed complication is collapse of the walls of the blood vessel causing the artery to become blocked. Stents were developed to prevent this from happening. This it does, however, although the vessel walls stay apart, the inside of the stent becomes filled with tissue that grows into the stent. Thus, stents often become occluded and the vessel still closes off.

From Harvard University comes a report on 175 patients who had stents inserted. Annual mortality was 2.7% and annual cardiovascular event rate was 10%. (35)

From the Cardiovascular Division of the University of Pennsylvania the three year outcome of 65 patient who underwent stenting was studied. Mortality was 4% per year and cardiovascular event rate was 14.7% per year. (36)

From the University of Giessen in Germany comes a detailed analysis of 300 patients who underwent primary angioplasty for an acute myocardial infarction.(37) Their findings are described in the following table.


  1 Month 6 Months 1 Year 2 Years 3 Years
All Cardiac Events 13% 22% 34% 42% 51%
Cardiac Mortality 4% 5% 6% 7% 9%
Total Mortality 5% 6% 9% 10% 13%
Repeat Angioplasty   20% 23% 25% 31%


IS THE PATIENT BETTER OR WORSE AFTER BYPASS SURGERY OR ANGIOPLASTY?

It will be apparent from the reports cited that the mortality rate, as well as other complications, of both coronary artery bypass surgery and angioplasty vary considerably. Outcome depends in large measure upon the patient's age, how much heart disease is present, the skill of the doctor who is treating the patient, and a host of other factors. A patient may be better off in the hands of a highly skilled surgeon than a cardiologist who never learned how to medically treat coronary artery disease. What is clear, at the very least, is that there is no advantage of either surgery or angioplasty over medical treatment. It is to be emphasized that no studies have shown that either of these two interventions will prevent heart attacks or premature death.

If revascularization does not prevent future heart attacks or death, what do these procedures accomplish. More importantly, do they cause any harm? The answer to this question is in the eye of the beholder. A sizable number of studies have been done where a variety of imaging procedures have been used to determine whether improvement in cardiac function occurs after revascularization. When the echocardiogram has been used, the focus has been on the motion of the heart muscle before and after revascularization. With radioactive imaging it has been blood flow to the heart muscle. With positron emission tomography (PET, the focus has been on metabolic function. Unfortunately, each of these procedures provide different answers. For example, a radioactive thallium study might show there is no blood flow to a given area. In contrast, A PET study might find metabolic activity. In the former instance, the prediction might be that there will be no functional recovery after revascularization while the PET study would predict that recovery would take place.

To complicate matters, imaging studies done immediately after revascularization will usually show more impaired function due to the trauma of the procedure used to restore function. If, however, the imaging study is delayed for several month, recovery will often be seen. It is here that the waters become even muddier. There is solid evidence that recovery will occur without any treatment whatsoever, although medical treatment will speed things up and increase the chances of recovery. This occurs through the heart's own revascularization process with the development of new vessels into the area where the coronary arteries are narrowed or blocked.

I will not bore the reader with a recitation of all the reports dealing with this matter. A recent report from the Department of Cardiology at the Academic Hospital in Leiden in The Netherlands has reviewed 37 studies using a variety of imaging procedures. (38) Improvement after revascularization occurred only 37-55% of the time. The remainder of the hearts studied were either no better or worse. The discouraging finding was that there was no reliable way to predict, in the individual patient, the likelihood of recovery from a revascularization procedure. Those who showed no viable heart muscle after a heart attack were less likely to show improvement, and those with viable muscle more often than not did show recovery. Unfortunately, a high percentage of those patients with viable muscle did not get better, and some of the hearts that appeared to be not viable recovered.

Both coronary artery bypass surgery and angioplasty will relieve recurring chest pains in subjects with coronary artery disease. In the case of bypass surgery 10-20% do not get effective relief while patients who receive angioplasty have a return of their symptoms in 40-50%. However, relief of pain will occur in 75% of patients without any treatment within 3-6 months because of the growth of new vessels. Medication will speed things up, and relieve pain in an additional 20%, with a far lower complication rate than accompanies mechanical revascularization.

Aside from the acute and subacute complications of angioplasty and bypass surgery, a major concern is the acceleration of the arteriosclerotic process in the coronary arteries that are treated. For example, vessels that are bypassed often show rapid progression of the occlusive process which led to the patient's symptoms. More importantly, collateral vessels that had developed over a period of time to compensate for a narrowed artery will usually disappear following bypass surgery. Thus, the ischemic heart muscle may actually be worse off following such surgery. The importance of these collateral vessels is illustrated by the fact that when a coronary artery is severely narrowed, and then becomes completely occluded, it has little effect on cardiac function. This is because there are enough collateral vessels to make up for the deficit in blood flow. In contrast, when a coronary artery is only mildly narrowed, and closes off suddenly, it is likely the patient will have a myocardial infarction or even die because the mildly narrowed coronary artery has not yet had a chance to develop new collateral vessels. Because of these facts, the common practice of rushing patients in for emergency or urgent surgery because of a severely narrowed coronary artery is completely unnecessary, and needlessly frightens the patient and his family.

Another possible long term side effect of bypass surgery is the increased incidence of cancer. While I have never seen a report about this relationship, personal observations of the author have shown a remarkable increased incidence of cancer in patients undergoing open heart surgery.

GEOGRAPHICAL VARIATION IN THE FREQUENCY OF CORONARY ARTERY BYPASS SURGERY AND ANGIOPLASTY

One of the facts that emerges from a review of the medical literature about bypass surgery and angioplasty is the enormous variation in the frequency with which these procedures are done. Such variation might be understandable if controversy existed over which patients should have such interventions, and when they should be done. The official guidelines of the American College of Cardiology and the American Heart Association recommend that symptomatic patients with good cardiac function be initially treated medically. (39) Surgery should be reserved for patients who are refractory to medical treatment. The guidelines suggest that patients with poor cardiac function might fare better with revascularization. However, this latter recommendation is based upon studies from 20 years ago when younger patients were operated upon by skilled surgeons and compared to the medical therapy of that day. It may no longer be true with older patients being operated upon by less skilled surgeons when compared to modern medical treatment.

These recommendations are straight forward enough. Thus, it is of interest to compare the frequency with which bypass surgery and angioplasty are used in different areas. In a recent study from Minneapolis-St. Paul and Goteborg, Sweden, the medical records of all patients hospitalized for a heart attack were compared. (40) Minneapolis-St. Paul was selected because its residents are primarily of Northern European origin. All 25 hospitals in Minneapolis-St. Paul and the two large hospitals in Goteborg participated in the study. A total of 2,460 hospital discharges from Minneapolis-St. Paul and 1,189 from Goteborg were reviewed. Coronary angiograms were done in 10% of the Goteborg heart attack patients. In contrast, 49% of the male patients and 39% of the women from Minneapolis-St. Paul had angiograms. Angioplasty was done on 5% of the men and 3% of the women from Goteborg, while it was done on 20% of the men and 15% of the women from Minneapolis-St. Paul. Bypass surgery was done on only 1% of the men and women from Goteborg, but on 12% of the men and 10% of the women from Minneapolis-St. Paul. In spite of these wide variations in the use of these procedures, there was no significant difference in the mortality at either 28 days or one year.

In another recent study of the use of cardiac procedures between the United States and Ontario, Canada, 224,258 Medicare patients were compared to 9,444 patients of a similar age.(41) In the U.S. patients 34.9% underwent coronary angiograms versus 6.7% of the Canadian patients. For angioplasty 11.7% U.S. patients had these procedure versus 1.5% of the Canadian patients. For coronary artery bypass surgery 10.6% U. S. patients underwent this treatment versus only 1.4% of the Canadian patients. The 30 day mortality for the U.S. patients was 21.4% versus 22.3% for the Canadian patients. At one year the mortality was 34.3% in the United States and 34.4% in Canada. Thus, there was a strikingly higher use of cardiac procedures in the United States without any significant benefit.

In a similar comparison study between the United States, Hungary and Poland in 8,000 patients with an acute myocardial infarction, 60% of the American patients had an angiogram before discharge from the hospital versus 20% in Hungary and 7% in Poland. Angioplasty was done three times more often and bypass surgery seven times more often in the United States. There was no difference in mortality in the different countries.(42)

Even in the United States there is wide variation in the frequency with which cardiac procedures are done after a heart attack. For example, a patient is the South Central United States is nearly twice as likely to have bypass surgery as a similar patient from New England and 1.5 x as likely to have angioplasty. Yet there is no difference in mortality at one year.(43)

The studies quoted above are just a small sample of many similar studies showing a wide range in the frequency with which patients with heart attacks and coronary artery disease are made to undergo costly, but unnecessary procedures that not only do not benefit the patient, but often increases morbidity and mortality. It's hard to escape the conclusion that these profitable procedures are done more for the benefit of the doctor and the medical institution than they are for the patient. Patients are reassured that these procedures will improve the quality of life. Unfortunately, they are not told whose quality of life will be improved. When the surgeon or cardiologist appears at the patient's bedside after surgery and exclaims, "Boy, we got to you just in time!", what he really means is that if they had waited any longer, the patient would have improved on his own.

Where does all of this leave us? According to major authorities in the field, most patients with coronary artery disease can be safely treated medically. (44, 45) The practice of doing immediate angiograms followed by either angioplasty or bypass surgery as the first treatment is unwarranted, and does not follow the practice guidelines. My recommendations are based on the guidelines I have successfully used in the treatment of my own patients during the past 22 years. During that time only eleven of those patients have had to undergo angioplasty or bypass surgery because they no longer would respond to medical treatment. In that same period, mortality from coronary artery disease and the incidence of heart attacks both have been less than one percent per year. The quality of life and freedom from symptoms in these individuals has been excellent.

While there is a possibility a patient may have a heart attack or die on a good medical program, in my opinion, this is far more likely to occur with angioplasty of coronary artery bypass surgery. The results of surgery are unpredictable, are accompanied by far more serious side effects including heart attack, stroke and death than patients are told, and are much higher in older patients. Mortality figures that cardiologists and surgeons quote in order to lure patients into the operating room often have little to do with reality. Thus, the treatment may be much more dangerous than the disease. If you must gamble, do so in Las Vegas, not on the operating table where you will bet everything you own on one roll of the dice. After all, if medical treatment does fail after 1-2 months, then surgery can always be attempted. But in the patients I have treated, that almost never happens.

Remember: The wonders of modern technology are so great that it is very easy for an incompetent doctor to masquerade behind the wonders of such technology. Thus, the doctor you choose to treat your heart disease may be more dangerous than your disease. So choose wisely.


REFERENCES

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