What is Coronary Artery Disease?
Coronary artery disease (CAD) is a health condition where the heart muscle doesn’t get enough blood and oxygen. This happens because the arteries that supply the heart with blood get blocked, leading to an imbalance between the oxygen demand and supply. Often, this blockage is caused by build-ups called plaques in the heart arteries, which interfere with the flow of blood. Importantly, CAD is the main cause of death in both the US and across the globe. At the start of the 1900s, it was a rare cause of death, but death due to CAD surged to its highest point in the mid-1960s. Even though these numbers have decreased since then, CAD still remains the top cause of death worldwide.
What Causes Coronary Artery Disease?
Coronary artery disease, a condition that affects the blood vessels supplying the heart, is influenced by many factors. These factors are divided into two groups: those you can’t change and those you can. Factors you can’t change include your gender, age, family history, and your genes. Meanwhile, factors you can change include smoking, being overweight, the levels of fat in your blood, and your mental health.
In the Western world, lifestyle choices have led to more instances of heart disease. Fast food and unhealthy meals, common in fast-paced lifestyles, are contributing factors. However, in the U.S, those in the middle and higher income groups tend to experience heart diseases later in life thanks to better primary healthcare. Nonetheless, smoking remains the top cause of heart and blood vessel diseases. As of 2016, it’s been found that about 15.5% of U.S adults smoke.
Men are more likely than women to develop this disease. High cholesterol, specifically high levels of “bad cholesterol” (known as LDL), increases your risk of developing heart disease. Conversely, high levels of “good cholesterol” (HDL), reduce your risk. One can estimate the 10-year risk for heart and blood vessel diseases using the ASCVD formula available online through the American Heart Association.
Lastly, inflammation within the body spotlights another risk factor. High Sensitivity CRP (hsCRP) is often used as a predictor of heart disease in some studies, although, its use in real-world settings is debated.
Risk Factors and Frequency for Coronary Artery Disease
Coronary artery disease, or CAD, is a common health issue around the world, present in both developed and developing countries. It represents a significant portion of global disease and is a major contributor to cardiovascular conditions specifically. The cost of treating this disease is substantial, with more than 200 billion dollars spent annually in the United States alone. Based on reports from the American Heart Association, it was estimated that 7.6% of men and 5.0% of women in the US had CAD from 2009 to 2012, equating to about 15.5 million people.
It’s important to note that the incidence of CAD increases as people get older. This is true for both men and women. As an illustration, a registry in France showed that the incidence of CAD was approximately 1% in people aged 45 to 65, and this percentage rose to about 4% in those aged 75 to 84.
Signs and Symptoms of Coronary Artery Disease
Before conducting further medical testing, it’s crucial to understand a patient’s medical history and complete a physical examination. Coronary artery disease, the blocking or damage of the heart’s blood vessels, may appear as stable ischemic heart disease or acute coronary syndrome. If not managed properly, this condition may escalate to congestive heart failure, which is a serious condition where the heart can’t pump blood as well as it should.
Patients should be asked about any chest pain, whether it’s related to physical activity, and if the pain spreads to the jaw, neck, left arm, or back. Breathlessness, both at rest and during activity, needs to be assessed. Other symptoms like fainting, fast heartbeat, rapid breathing, swelling in the lower legs and ankles, shortness of breath at night when lying flat, and the ability to exercise should also be discussed. Information about the patient’s family history of heart disease and their diet, smoking habits and lifestyle should also be gathered.
- Chest pain
- Pain spreading to the jaw, neck, left arm, or back
- Breathlessness at rest and during activity
- Fainting
- Fast heartbeat
- Rapid breathing
- Swelling in the lower legs and ankles
- Shortness of breath at night (orthopnea)
- Exercise capacity
- Family history of heart diseases
- Dietary, smoking, and lifestyle habits
The physical examination must include inspecting the patient, feeling their body for anything unusual, and listening to their heart and lungs. The doctor should look for any obvious signs of distress, swelling in the neck veins, and swelling of the legs and ankles (peripheral edema). The doctor should gently touch the patient to check for excess fluid or heart muscle enlargement. If there is swelling in the legs or ankles, its extent needs to be evaluated. The degree of neck vein swelling also needs to be measured. As part of the examination, the healthcare provider should listen to the heart in all four areas and also the lungs, especially in the lower areas.
Testing for Coronary Artery Disease
If you or your doctor suspect that you might have coronary artery disease, there are quite a few tests available to help confirm or rule out the diagnosis. These tests include an EKG (electrocardiogram), an Echo (echocardiogram), a chest X-ray, a stress test, a cardiac catheterization, and various types of blood work.
The EKG is a straightforward but highly informative test. It measures the heart’s electrical activity and can provide your doctor plenty of insights about your heart’s health. Any abnormalities, such as changes in heart rhythm or the presence of acute and chronic heart issues, can be picked up via an EKG. This type of testing is cost-effective and does not depend on the user’s skill or experience to be effective.
The Echo is essentially an ultrasound for the heart, and it can be utilized in both acute (short-term) and chronic (long-term) cases. It can help doctors identify wall motion abnormalities, valve issues, chamber sizes, and even inflammation. Echo is also the go-to method for guiding heart-related procedures like pericardiocentesis, which involves using a needle to remove fluid from around the heart. Just know that Echo can be pricer compared to an EKG and the user’s experience and skill can affect the outcomes.
The stress test involves artificially exposing your heart to stress to see how it responds. Particularly, in this test, doctors are looking for changes in EKG readings or symptoms that may be indicative of coronary artery disease.
Chest X-rays can provide a clear view of your heart, lungs, and vessels, making them an important part of the diagnosis process. Alongside the physical tests, blood work can offer important information about the heart’s overall health and response to treatments.
If needed, a doctor may order a cardiac catheterization — a more invasive but also the most accurate test to evaluate coronary heart disease. This procedure is usually reserved for intermediate to high-risk patients or for emergency situations. The downsides of this test are the potential for complications, the need for moderate sedation, and the risk of an allergic reaction or kidney injury from the contrast dye used.
Treatment Options for Coronary Artery Disease
Coronary artery disease can show up in two forms: stable ischemic heart disease (SIHD) or acute coronary syndrome (ACS). SIHD is a long-term condition, while ACS is a more immediate, urgent issue. The treatment depends on which type of disease you have.
Stable ischemic heart disease usually gives you chest pain or pressure, which gets worse with physical activity or emotional stress. The pain can be relieved by resting or taking nitroglycerin. Some people, especially women, elderly people or diabetics, might not experience the typical chest pain and instead have different, unusual symptoms. Treatment for SIHD includes lifestyle changes and medications. You should stop smoking, exercise regularly, lose weight if needed, control diabetes or hypertension, and eat a healthy diet. You may also need medication to protect your heart and control your chest pain.
Everyone with SIHD should have low dose aspirin, beta-blocker, nitroglycerin when needed, and a type of drug called statin. If these don’t control your symptoms, doctors might increase the dose of beta-blocker, or add calcium channel blocker and long-lasting nitrate. They might also consider adding a drug called ranolazine. If medication doesn’t work, the next step is a heart test called cardiac catheterization. This procedure helps doctors see the heart problem in detail and decide whether you need a heart procedure to open up or bypass blocked arteries.
Acute coronary syndrome is a sudden serious heart condition. Symptoms include severe chest pain or pressure, which may spread to the neck and left arm. You might also feel short of breath, dizzy, faint, or have a sudden heart stoppage or heart failure symptoms. You’ll need an electrocardiogram (EKG) quickly to check for severe heart damage. If the EKG shows signs of damage, you’ll need an emergency heart procedure in a specialized hospital. If you can’t get to such a hospital in 2 hours, then you’ll get a medicine to break up clots in your blood vessels.
Doctors will confirm that your symptoms are indeed due to a heart problem and not other conditions that look similar on an EKG. You’ll get a full dose of aspirin immediately, and nitroglycerin for pain unless it’s contraindicated. You’ll also get a high dose of a type of drug called statin, and a beta-blocker. You might get a blood thinner and another drug to further prevent clotting based on your condition. For a less severe form of ACS, doctors advice quick invasive therapy within 24 hours if you have moderate to high risk of having more heart problems.
Regular check-ups with your heart doctor and primary care doctor are very important in managing your heart disease. Following the medication regimen and making lifestyle changes are also crucial.
What else can Coronary Artery Disease be?
When trying to diagnose coronary artery disease, doctors need to consider several other conditions due to the heart’s closeness to various organs like lungs, stomach, large blood vessels, and the muscular system. Chest pain that feels like angina (a specific kind of heart pain) could indicate a wide range of conditions. Some of these include acute pericarditis (inflammation of the heart’s lining), myocarditis (inflammation of the heart muscle), a type of angina called Prinzmetal angina, fluid around the heart (pericardial effusion), acute bronchitis, or pneumonia.
This chest pain may also signal a condition affecting the lung lining (pleuritis), fluid in the lungs (pleural effusion), a tear in the body’s largest artery (aortic dissection), or stomach and esophagus issues, such as gastroesophageal reflux disease (GERD), peptic ulcer disease, or esophageal motility disorders. In some cases, the problem could even be musculoskeletal, like costochondritis (inflammation of the chest’s cartilage).
Similarly, stable ischemic heart disease, a condition involving reduced blood flow to the heart, can often be mistaken for GERD, peptic ulcer disease, costochondritis, and pleuritis. To confirm the diagnosis of these conditions, doctors need to rely on the patient’s medical history, a physical examination, and various diagnostic studies.
What to expect with Coronary Artery Disease
The outcome of a disease can depend on many things. Some of these factors can be changed, while others can’t. Examples include a person’s age, gender, family health history, genetics, race, diet, smoking habits, and whether they take their medication regularly. Access to healthcare and financial status also play a part, as does the number of arteries affected.
Having other health conditions like diabetes, high blood pressure, high cholesterol, and chronic kidney disease can also influence the overall outcome of the disease.
Possible Complications When Diagnosed with Coronary Artery Disease
Coronary artery disease can lead to several complications like:
- Arrhythmias or irregular heartbeats
- Acute coronary syndrome, which includes conditions like heart attack or chest pain
- Congestive heart failure or when your heart doesn’t pump blood as well as it should
- Mitral regurgitation or a leaky heart valve
- Ventricular free wall rupture, which is a tear in the heart muscle
- Pericarditis or swelling and irritation of the thin saclike membrane around your heart
- Aneurysm formation or abnormal blood-filled bulge in the wall of a blood vessel
- Mural thrombi or blood clot in the heart’s chambers
Preventing Coronary Artery Disease
Coronary artery disease, a condition that affects the heart’s blood vessels, is influenced by factors that can be changed – modifiable – and factors that can’t be changed – nonmodifiable. Regular health check ups with primary care providers often focus on changing these modifiable risk factors. These include managing diseases like diabetes, high blood pressure and high cholesterol levels, quitting smoking, losing weight and exercising more. All these steps can have a big impact in preventing this disease. Because this is a worldwide health issue, education programs in schools and various media outlets should work on raising awareness about it.