What Doctors know about Heart Disease
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Symptoms of Coronary Artery Disease.......................................................................... 76 Symptoms of Stroke or Cerebrovascular Disease..........................................................80 Symptoms of Peripheral Vascular Disease .................................................................... 82 Things to Remember about this Section ....................................................................... 85 Screening for Heart Disease ...................................................................... 86 Common Screening Tests .............................................................................................. 86 Other Screening Tests for Heart Disease ......................................................................88 The Framingham Risk Score ......................................................................................... 90 Things to Remember from this Section ......................................................................... 93 Diagnosis of Heart Disease ....................................................................... 94 Diagnosis of Acute Coronary Syndromes ...................................................................... 94 Diagnosis of Cerebrovascular Disease ......................................................................... 102 Diagnosis of Peripheral Vascular Disease ................................................................... 104 Things to Remember from this Section: ..................................................................... 108 Treatment Options for Heart Disease ...................................................... 109 Treatment of Angina .................................................................................................... 109 Treatment for Acute Coronary Syndromes .................................................................. 113 Treatment of Strokes .................................................................................................... 115 Treatment of Peripheral Vascular Disease ................................................................... 118 Things to Remember about this Section ...................................................................... 121 Complications and their Management..................................................... 123 Complications of Acute Coronary Syndromes ............................................................ 123 Complications of a Stroke ............................................................................................ 129 Complications of Peripheral Vascular Disease ............................................................. 131
Things to Remember From this Section ...................................................................... 132 Preventing Heart Disease ........................................................................ 133 What about Dietary Measures? ................................................................................... 138 Things to Remember from this Section ....................................................................... 145 Living with Heart Disease ....................................................................... 146 Living after a Heart Attack .......................................................................................... 146 Taking Medications after a Heart Attack .................................................................... 153 Living after a Stroke ..................................................................................................... 156 Living after a Diagnosis of Peripheral Vascular Disease ..............................................157 Important Things to Remember from this Section ..................................................... 160 Current Research ..................................................................................... 161 Things to Remember from this Section ....................................................................... 167 The Future .................................................................................................................... 168 Things to Remember about this Section ......................................................................172 Conclusion ............................................................................................... 173
PREFACE In this audiobook, we are going to talk about the important topic of heart disease, including what doctors know about it and what they are doing to combat it. Heart disease is the number one killer of people worldwide so the more we understand about it in both the lay community and the medical community, the healthier many people will be throughout their lives. Before we get too far into this discussion, we should probably talk about what we mean by “heart disease”. While babies born with congenital conditions affecting the structure of the heart technically have a type of heart disease, we call it congenital heart disease, which is a far different thing from the kind of heart disease we will talk about in this audiobook. In addition, it cannot be stressed enough that the term “heart disease” means a great deal more than just a disease of the heart. Heart disease certainly affects the heart but the same basic reasons it affects the heart are identical to the reasons people have strokes or need to have their legs amputated because of poor circulation. In that sense, heart disease is not really a disease affecting the heart but is more a disease of the blood vessels in general. Sure, a person who’s had a stroke looks different and has different challenges than one who’s had a heart attack but they essentially have the same disease. This is why a better term for heart disease is “cardiovascular disease” because this term better reflects just how widespread this abnormal process can be inside the human body. As you will learn in this audiobook, there are reasons why cardiovascular disease can affect the heart, the brain, and the peripheral arteries in the arms and legs in exactly the same ways. Another basic truth about heart disease is that it is partly a disease of genetics and partly a lifestyle disease. Many people don’t like to hear this, but for different reasons. The person whose father or grandfather died young because of a heart attack might feel scared and resigned to the fact that this could happen to them as well. On the other hand, if you’re a person with what we call “modifiable risk factors” for heart disease, you
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might feel upset that you have to change your lifestyle in order to avoid early disability or an early death because of the choices you’ve made. The good news is that all is not lost for the person with a strong family history of heart disease as was once the case. That person can make the necessary lifestyle changes or take important preventative medications now offered by modern medicine to make a difference in whether or not they will become a victim of their family history and genetic makeup. This is also good news for the person with modifiable risk factors for heart disease. The operative word here is “modifiable”, which means you can make choices that will alter the course of heart disease in your life. Even people who already have heart disease can make choices to better their lives after a heart attack in order to avoid further heart damage and disability. While this audiobook is written for adults, you should take what you learn from it and think about your children and grandchildren as you learn about this disease process. Why, you ask? It’s because the prevention of heart disease is not something you do in your forties or fifties as you begin to worry about having a heart attack. It is something every child should know about early in their lives so they can make lifetime choices that could mean the next generations are healthier than this one, just as we are hopefully healthier today than our parents and grandparents were. In this audiobook, you will learn about how your heart and blood vessels are supposed to work when they are healthy as well as what happens to make both of these things go awry, leading to permanent disability and death should a heart attack or stroke actually happen. You will understand what doctors have learned about heart disease so far and what’s currently being studied about this disease in research facilities throughout the world. Today’s doctors know much more about heart disease than they used to and, after listening to this audiobook, hopefully you will know more too. We still don’t know everything we need to learn about it yet; there are still people dying every minute around the world because of this devastating disease process. In your own life, however, you might learn enough about it to feel better prepared to do what you can to make sure
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you die of “old age” and not of a stroke or heart attack before your time. Good luck and listen carefully in the hours ahead, for the life you save could be your own.
THE HISTORY OF HEART DISEASE IN THE WORLD Many people, including most modern-day doctors, believe that heart disease is something brand new to mankind—a product of our crazy, hectic lifestyles and the tendency toward bad habits—that have led to heart disease and stroke being the major cause of death in recent years in just about every part of the world. But is this really true? Ancient man knew nothing about Big Macs and extra-large fries so maybe they didn’t have this problem. As it turns out, researchers asked themselves this very question and studied heart disease and its precursor, called atherosclerosis, as it existed in ancient cultures. An article was published in a major medical journal, Lancet, in 2013, that dealt with the incidence of heart disease in ancient peoples. Researchers studied mummies from vastly different parts of the world, including Peru, Egypt, and the Aleutian Islands to see if they showed evidence of the disease. Surprisingly, as far back as four thousand years ago, atherosclerosis and probable heart disease existed in humans. While it would be impossible to say what each mummy actually died from, they looked at the arteries of 137 mummified remains and found evidence of atherosclerosis in about a third of them. As you will learn, atherosclerosis basically means narrowed arteries and narrowed arteries are the main cause of all types of heart disease. The scientists used CT scanning, which involves 3D x-ray technology to look at the arteries of these mummies without having to dissect them. As it turns out, heart disease is not necessarily a modern disease. Nobody did autopsies on the recently deceased in ancient times and, while several ancient Greek physicians learned how to perform this important examination, Roman law later blocked doctors from doing them until the time of the Renaissance in Europe. When doctors were able to study the internal workings of the body after death in the fourteenth century, they were able to find evidence of coronary artery disease, which 3
essentially means blockages of the major arteries that supply the heart, in many of them. What they weren’t able to do at the time, however, was make the connection between what they were finding on the autopsies and the actual presence of clinical heart disease. Homer’s writings from about 800 BC have helped us understand whether or not doctors even recognized heart disease in Ancient Egypt and Ancient Greece. His work and evidence found on ancient papyri from 3000 BC told us they understood that it was a bad disease. They wrote that, if a man had stomach pain that also affected the breast area and the arms, this usually meant he was at risk for imminent death. Herbal remedies were recommended but it is doubtful they were ever helpful once a heart attack was already happening. Unfortunately, no one understood at the time exactly what this disease was all about. Again, autopsies were never done and, even if they had, the doctors from that time period would have had a difficult time combining information from autopsies and clinical findings in order to put two and two together. They wouldn’t have been able to correlate the symptoms with the autopsy results. One of the first and clearest descriptions of angina pectoris or heart-related pain comes from a love poem written in Ancient Arabia, in which the poet described racing heartbeats and episodes of fainting, and spoke of his heart being “tightly squeezed” by a bird’s claw. It is believed the poet probably had heart disease from which he later died. More doctors and scientists talked about heart-related angina pain from as far back as the days of Leonardo da Vinci. He wrote himself about thickening of the blood vessels in older people that restricted the flow of blood. He was greatly interested in anatomy, mainly because he thought it would help his painting, and wrote about the anatomy of the heart and blood vessels. William Heberden, however, really advanced the interest in heart-related angina pain when he presented a paper on the subject to physicians in London in 1768. He called his paper “Some Account of a Disorder of the Breast”, which says a lot about what they didn’t know about heart disease. Nevertheless, the symptoms of angina pain with activity and angina at rest were clearly described. He even wrote about the influence of
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mental stress on developing the disease. Heberden called these symptoms “angina pectoris”, which means “strangling chest”. Another doctor, John Hunter, wrote firsthand about angina pectoris in the eighteenth century, mainly because he had the condition himself. He also talked about the relationship between this heart-related pain condition and his emotional state. Interestingly, he died of a sudden heart attack after a fight with a colleague. In his autopsy, doctors found a blocked artery but still weren’t sure this finding was related to the Hunter’s symptoms and sudden death. Finally in 1761, Giovanni Morgagni, who was an Italian anatomist, first described what he called “hardening of the arteries”. Others of the same time period eventually linked this “disorder of the breast” to actual hardening of the arteries. Things became clearer still in the middle of the nineteenth century when Rudolf Virchow, a famous pathologist, studied blockages of the arteries called thromboses and attempted to find out what risk factors contributed to these pathologic findings. This was the first time that doctors began to take coronary heart disease seriously and studied it further. In the last part of the Nineteenth Century, scientists worked with dogs in order to understand heart disease better. They blocked some of the arteries leading to the heart and found that the heart soon quivered and that dogs died. By 1879, doctors finally began to understand that heart attacks were from blocked arteries. Later, they showed blocked arteries in several human patients caused them to die from a myocardial infarction, which is the medical term for heart attack. In 1912, the electrocardiogram was first used to identify these heart attacks. One of the most important modern milestones in heart disease research and in the identification of heart disease came in 1958, when doctors at the Cleveland Clinic used dye injected into the coronary arteries, which are the main arteries supplying blood to the heart muscle. This procedure helped identify the inner workings of these arteries and doctors became better able to study these arteries in both healthy and sick patients. Researchers believed at the time that such a procedure would kill the patient and were relieved to find that it was actually relatively safe to do.
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At first, they thought the dye had to be injected directly into these coronary arteries, which would have been risky and involved surgery. Within a short period of time, however, they found a way to put the dye through a catheter first placed into the femoral artery in the groin. This was found to be an excellent and safe method of identifying heart disease with a simple outpatient procedure. Doctors still use this procedure today, which is called coronary angiography. Soon after and continuing until the present time, doctors turned what they knew about blockages of the heart seen in the coronary artery angiogram procedure into treatments that could actually help patients with heart disease. Medical treatments, surgery, and methods of opening the coronary arteries without a major surgery were developed. They also discovered that not everyone with heart disease needed the same treatment. Patients with milder areas of blockage improved with medications and lifestyle changes, while those with very severe disease were often treated with what is called a CABG surgery, pronounced as “cabbage”. This stands for coronary artery bypass graft. We will talk about this surgery later. Lastly, they developed far less invasive and risky ways to open blockages and put stents into them, which are tiny tubes that kept blocked areas open. This kind of procedure did not require open surgery and could be used on many types of heart disease patients. Other advances in heart disease treatment have been developed since the early 1960s. Doctors used to think that heart attack patients should be placed in a quiet place in the hospital without any monitoring but soon discovered just how risky that was. They developed the idea of the coronary care unit or CCU, which involved close monitoring of these patients with continuous electrocardiography after their heart attack. This cut the death rate after a heart attack by fifty percent. CABG procedures got better as well by this time. Doctors were able to identify areas of blockages in the arteries of the heart and improved surgical methods to bypass these blockages so that even more patients could survive a heart attack or keep one from ever happening in the first place. Nowadays, CABG surgeries are less often done because most patients with a heart attack are treated with medications and noninvasive techniques to open blocked arteries and place stents inside them.
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The 1970s brought new advances in the drug treatment of coronary heart disease. They found out that giving aspirin to heart attack patients improved their survival and identified other drugs used to prevent heart attacks or treat their complications. Cholesterol-lowering drugs, for example, were found to be particularly helpful in preventing heart attacks. The other main advances in heart disease treatment have been uncovered since that time and we will later talk about each of them. These include things like cardioverters and defibrillators, which shock the heart in order to restore a more normal rhythm, thrombolytic drugs, which are also sometimes called “clot-busting drugs” used to open blocked arteries, pacemakers to control heart rhythm problems, and implantable defibrillators, which could shock the patient’s heart even when they weren’t in a hospital. In more recent times, the focus on heart disease has shifted from ways to treat heart attacks toward ways to prevent this dangerous complication of blocked arteries. More was understood about the risks for heart disease so doctors could make use of medications and lifestyle recommendations to educate people on their role in heart disease prevention. With these tools, patients themselves were able to participate in caring for their heart in ways that kept them from having a potentially fatal heart attack or stroke. In short, we have come a long way from first describing what it feels like to have narrowing or blockages of the coronary arteries to understanding why these blockages occur in the first place. The treatment of major heart attacks has vastly improved in recent years and the importance of heart disease prevention has come into the forefront of the medical management of this devastating disease.
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IS HEART DISEASE A MODERN DISEASE OR NOT? While heart disease has certainly been around since ancient times, it is still considered mostly a modern disease. Doctors studied the incidence of heart disease over the years since data were first collected from about 1900. At that time, heart disease was just the fourth common cause of death in the US. The number of deaths due to heart disease peaked in the 1960s and, largely due to improved treatment of heart attacks, this number has steadily declined but is still higher than it was in 1900. Mostly because of lifestyle habits, deaths due to heart disease increased after 1900 so that by the 1930s, it was the commonest cause of death—a statistic that still exists today. Part of the increase in heart attacks in the early part of the Twentieth Century had to do with an increase in both cigarette smoking and cholesterol levels in the population. The declines that followed the 1960s era occurred because there were fewer smokers and better care for heart attack patients in general. In addition, people were generally living longer because fewer of them died from infectious diseases. This also contributed to an increase in heart attack deaths. Lastly, some of the increases in heart attack deaths seen after 1900 happened because doctors were better able to recognize that a heart attack had occurred. It wasn’t until 1912 that heart attacks were first identified in living people. The ECG or electrocardiogram was used more often to make the diagnosis of a heart attack so, if the patient later died, it was more likely to be listed as the cause of their death. On the other hand, no one can agree on why heart attack deaths have decreased since the 1960s. Factors that have been suggested include a lower incidence of narrowing of the arteries in the population. Researches studied the autopsies of healthy young men who died as wartime casualties in the Korean War, Vietnam War, and the wars in the Middle East. During the Korean War years, as many as 77 percent of these men had some evidence of coronary artery disease, which is basically narrowing of the blood vessels because of cholesterol-containing plaques inside the vessels. These were otherwise healthy men with no symptoms whatsoever of heart disease. This number dropped to 45 percent
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among casualties of the Vietnam War and to only 8.5 percent in the servicemen who died in the Iraq and Afghanistan wars between 2000 and 2011. Other factors believed to have made a difference in the incidence of coronary artery disease since the time of the Korean War were reductions in the number of people who smoked and lower cholesterol levels in the population. In 1964, the Surgeon General first warned people about the dangers of cigarette smoking so that, while 42 percent of people smoked in 1965, only 18 percent of people smoked by 2011. The average total cholesterol levels have dropped during this time as well. Researchers found that the average total cholesterol was 217 milligrams per deciliter in 1960, while this number dropped by 2010 to about 194 milligrams per deciliter. As you will soon learn, high cholesterol levels are strongly linked to the development of heart disease. Part of this decline is due to the fact that cholesterol-lowering drugs, called statin drugs, were first introduced in 1987. Finally, more was learned during this time about how people at risk for heart disease could improve their chances of avoiding a heart attack through increased physical activity, quitting smoking, treating high blood pressure, and taking medications to prevent heart attacks. Risk factors for heart disease were identified in their earliest stages so that people could make these important lifestyle changes as soon as the risks were identified. So far, we’ve been talking about the change in heart attack death rates in the last 120 years. What about the prevalence of coronary heart disease itself? Because most patients who have this problem do not know it, we really don’t know the actual prevalence of this problem in the United States. In one survey in 2010, about 6 percent of adults indicated they’d been told they had heart disease. Researchers at the Mayo Clinic found that 37 percent of autopsies done between 1979 and 1994 showed real coronary heart disease in 37 percent of people who didn’t know they had it. In a related study, it was discovered that only 17 percent of men and 22 percent of women who had their first heart attack already knew they had heart disease. During the same years of the Mayo Clinic study, the incidence of sudden cardiac death declined by 17 percent.
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Doctors also measured the change in the incidence of heart disease over time by looking at the numbers of people hospitalized after a heart attack between 1970 and 2010. Interestingly, they found a 29 percent relative decline in hospital admissions following a heart attack over those 40 years. This is even more significant considering that, during this timeframe, it became easier to detect subtle heart attacks that wouldn’t have even been identified in 1970. The people who seem to have benefited the most from improvements in heart disease treatment and better prevention strategies for the disease in the last 50 years are those under 65 years of age. In 1970, 53 out of 10,000 people in this age group were hospitalized after a heart attack. This number declined sharply over time, so that only 26 people out of 10,000 were hospitalized for the same disease in 2010. This was followed by the finding that the average age of a first heart attack increased from 63 years in 1975 to about 73 years in 2005. Lastly, there has been a downward trend in the numbers of people who die from their heart attack. In 1970, 16 percent of people under 65 years who had a heart attack died from the event. This number is now less than 2 percent. Older patients died of a heart attack at a rate of 38 percent in 1970, while only 7 percent die from a heart attack after 65 years of age today. Some of these statistics don’t mean as much when you consider that, because mild heart attacks are now identified with more accuracy, people with milder cases of heart disease are treated and have better outcomes because their heart attack wasn’t as bad to begin with. Perhaps the saddest cases of heart attack deaths are those who simply collapse and die from a heart attack without the ability to be aggressively treated for their heart attack before they die. This can be the first sign of heart disease in some people. Autopsies have shown that only half of all patients who have what’s called sudden cardiac death knew they had heart disease before they died from it. Because it is so devastating when it occurs, nearly two-thirds of heart attack deaths happen this way. Researchers have been able to document a 60 percent decrease in deaths from sudden cardiac death in men and a similar 69 percent decrease among women between the years 1975 to 1988.
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So, it’s probably fair to say that, while there has been evidence discovered of the existence of heart disease since ancient times, this is probably still a disease of modern mankind. The good news is that, after it became clear that heart disease was a major health concern, efforts to reduce its influence on the health of the world’s population have paid off so that fewer people have untreated risk factors for heart disease and not as many people have symptomatic heart disease or deaths from a heart attack than was the case just 60 years ago.
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THINGS TO REMEMBER FROM THIS SECTION: •
Scientists have found evidence of heart disease in people who lived in ancient times all over the world.
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It took centuries before the linkage between blockages in the arteries and the development of heart-related symptoms like angina pectoris was established.
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Not until 1912 was it possible to identify the presence of a heart attack in living persons.
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Heart disease was only the number four cause of death in 1990; from 1960 until today, it became the number one cause of death in the world.
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Part of the reductions in heart disease since 1960 have happened because fewer people are cigarette smokers and cholesterol levels have modestly declined.
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More people are identified as having mild heart attacks now than in 1960, resulting in earlier treatment and better overall outcomes after suffering their first heart attack.
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The risk of sudden cardiac death has decreased in the past 60 years, which also improves the statistics on deaths due to heart disease.
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BACKGROUND INFORMATION AND STATISTICS ON HEART DISEASE As mentioned, heart disease or, better yet, cardiovascular disease, is a disease involving both the heart itself and the blood vessels. Because blood vessels travel everywhere in the body, this means that, technically, heart disease can show itself in other parts of the body besides the heart. The two main cardiovascular diseases most people think of when talking about heart disease are called angina and myocardial infarction, which is the same thing as a heart attack. Together these are called coronary artery disease. Angina is actually more of a symptom than an actual disease. This involves the sensation of chest discomfort, shortness of breath, and sometimes nausea that generally comes on with exercise and goes away with rest. In some people, this is the first sign they have cardiovascular disease. Doctors divide angina into two different types. Stable angina is the best type to have, if there is such a thing as the “best type of heart disease”. When a person has stable angina, their symptoms are specifically related to exercise or other times when the heart is stressed and the heart rate increases. There is no real damage to the heart in stable angina but it is a sign that, when the heart actually needs better blood flow, such as with exercise, it isn’t getting it. The result is heart-related chest pain. In unstable angina, the pain and other symptoms are essentially the same but these things happen at rest instead of with activity. It can come on randomly, including during sleep, and it is impossible to tell if the pain is from unstable angina or an actual heart attack without a thorough evaluation in the emergency department. What’s risky about unstable angina is that it is a sure sign that the real thing—a heart attack—will probably happen in the future. As in stable angina, there is no real heart muscle damage with unstable angina. A myocardial infarction or heart attack involves some type of blockage in the coronary arteries that supply the heart muscle. The person with a myocardial infarction has the 13
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