Angina is one of the most common causes of admission into the ER (Emergency Room), and it is the first thing that will cross a physician’s mind when a patient reports chest pain, especially if the patient is above 40 years old. Knowledge of how angina feels like is essential for everybody in order to warn him/her that they should seek urgent medical care. Thus, here we will discuss how angina feels and what warning signs you should watch for.
It is important to know that angina is a clinical presentation that may precede a heart disease rather than the disease itself, and therefore it changes from one person to another according to the severity and nature of the disease itself and the condition of the patient. For example, a diabetic patient may not feel any pain at all due to an abnormal function of his/her nerve endings responsible for the transmission of pain; also, women tend to have a different form of pain and a greater incidence of other symptoms as it will be discussed later.
Angina Symptoms
1. Chest pain
Chest pain remains to be the primary symptom of angina and the reason why the patient seeks medical care. In angina, pain is quite characteristic, and an experienced doctor can suspect angina by just listening to how the patient describes his or her pain. Anginal pain feels more like a pressure or squeezing sensation than actual pain. Since angina is caused by a supply mismatch, where the heart can’t get enough oxygen to perform its function, the condition worsens when the heart’s demands of oxygen increase. That’s why anginal pain is aggravated by physical or emotional exertion and is relieved by rest.
Angina patients know the amount of effort that is needed to induce their pain and, therefore, can predict their anginal attacks to some extent. Anginal pain can rarely be felt as stabbing rather than pressure especially in women who may have an atypical complaint about angina. The localization of pain differs between people, but most common sites include the chest just beneath the breastbone, left shoulder, and less commonly along the left arm or jaw. It may rarely even be felt in the upper abdomen. Anginal attacks are brief and last from 1-10 minutes, and if the pain lasts for less than a minute, it points towards a non-anginal cause of chest pain, while if it lasts for more than 10 minutes without relief, it may be due to a heart attack, which is a broad term that signifies a more significant reduction of blood supply to the heart whether due to complete or near-complete occlusion of the heart’s blood vessels (the coronaries).
2. Breathlessness and panic
The second most common complaint of anginal patients is breathlessness, but it occurs in most diseases that affect the chest. In case of angina, it is due to the dysfunction of the heart’s pumping mechanism due to the deprivation of oxygen in the cardiac muscle. It tends to be exertional, and the triggering effort needed to start this type of pain gradually decreases. Patients suffering from anginal pain also tend to panic and have a feeling of impending doom. This is also associated with dyspnea (breathlessness) and tachypnea (rapid breathing). It is mostly psychological rather than an actual breathing problem and is relieved when the anginal attack is abated.
3. Nausea and vomiting
It may sound strange, but nausea and vomiting are included as common manifestations of ischemic heart diseases (diseases where the heart can’t get enough blood). It occurs because the parts of the heart not receiving blood tend to “irritate” the vagus nerve, which is responsible for feeling nausea and supplies the muscles that help us vomit.
4. Dizziness, fainting, and palpitations
Our hearts are the pumps that deliver oxygen through our blood to the body. When such supply is compromised, organs start to dysfunction. Such pumps act by a specific and regular rhythm through a pacemaker that is in our heart. On the other hand, the heart itself needs a constant oxygen supply through the coronary arteries, when this is not supplied efficiently, the heart’s pacemaker starts to dysfunction, and the heart rate begins to fluctuate. This fluctuation makes us feel our heartbeats, which doesn’t normally occur unless the rate or rhythm changes -as a good example, we may feel a pounding in the chest after climbing a long flight of stairs or running for a long distance- and this is called palpitations. Such irregularities of heart rate affect the blood supply to our brains, which are the most vulnerable of our organs to oxygen deprivation, thereby leading to dizziness and, in more severe cases, syncope or fainting.
5. Profuse sweating
Humans sweat when their bodies temperature rises; it tends to lower the temperature and keep it constant for the body’s systems to function correctly. However, in the case of angina, sweating is a side effect of the activation of our sympathetic nervous system, the system that our ancestors developed as a fight or flight response to stressful situations. Any sweating without fever or hot weather is enough to seek medical care.
The previous symptoms are the most common presentations for angina pectoris. However, these presentations may differ in some situations Women tend to have sharp pain or even abdominal pain. They may also complain of a general sense of weakness and fatigue or weight loss. This is because the type of angina that affects women tend to be of a different mechanism than that which affects men. Also, women tend to be more neglecting regarding their medical health; that’s why women should never ignore these subtle signs and seek medical help.
» Now, let’s discuss the causes of angina.
Angina Causes
Angina is a state of imbalance between the heart’s demands of oxygen which is essential for the production of energy by the heart’s muscle, and the supply of this vital nutrient. The heart’s blood supply comes from blood vessels called coronary arteries, and they originate from the aorta, which is the main blood supply for the whole body, except for the lungs.
The most common cause for such insufficiency is what we call coronary artery disease or “CAD.” It is mostly caused by the narrowing of the coronaries by the deposition of fat into their walls which is better known as atherosclerosis. Usually, this is a normal senile process that occurs over the years following the mid-twenties in human lives. However, it is sped up in some people who may start experiencing anginal pain in their forties or fifties and more recently owing to the trends of fast food and sedentary lifestyle.
It is hard to point out at a unique cause for angina because of two reasons; the first one is that there is more than one type of angina, and each type has its own causes. The second reason is that for the coronaries to be narrowed by fat, they need a multitude of factors.
To make things a little bit easier, let’s take the “risk factors” for atherosclerosis one by one and see how can they cause such condition or rather, become a predisposing factor:
1- Smoking
Tobacco smoking causes hypertension, injures the walls of your arteries, and makes them more liable for atherosclerosis by depositing lipids (fats). It also promotes insulin resistance which increases the risk of type 2 diabetes, makes your blood “thicker” and makes your platelets more liable to “stick” together, thereby increasing the risk of having a fatal heart attack by clogging your arteries, cutting this way all blood supply to a part of your heart. That’s why it is widely accepted that smoking is the leading cause of preventable death in the world.
2- Diabetes
Diabetes a clinical condition where your body either can’t produce insulin or has developed resistance to the action of this hormone. This leads to the inability of the body to use glucose sugar which makes it resort to using other sources for energy. The most important alternative source for energy is fats, so it “mobilizes” fats from their stores, increasing their levels in the blood and accelerating atherosclerosis.
3- Obesity
Obesity increases the amount of circulating fats in your body, especially LDL cholesterol, which is the harmful type of cholesterol. Abdominal obesity also increases insulin resistance predisposing to diabetes type 2.
4- Sedentary lifestyle / Physical inactivity
Regular exercise boosts the heart’s health and helps establish new vascular connections in the heart. It also increases the level of HDL cholesterol (the good cholesterol) at the expense of LDL cholesterol, reduces weight, and therefore delays and slows atherosclerosis. It is advisable to exercise regularly for at least 20-30 minutes a day to achieve good cardiac health.
5- Hypertension
Chronically high blood pressure causes excessive stress on blood vessels which injures the vessel walls, predisposing to atherosclerosis.
6- Chronic or repetitive stress
Emotional stress causes a surge of blood pressure and excessive release of stress hormones that narrows arteries, and decreases blood supply to the heart, aggravating angina.
7- Family history
A family history of angina or similar conditions is a strong risk factor for angina. It may be related to multiple conditions, such as familial hypercholesterolemia, where individuals of a certain family have a tendency to have high levels of blood cholesterol due to metabolic defects.
8- Excessive alcohol consumption
Alcohol, when used in excess, might predispose to hypertension and alters the balance of HDL and LDL cholesterol, thereby increasing anginal risk.
9- Advanced age
As mentioned before, the pathology causing angina is gradual, and although the pain is acute or sudden, the events leading to it takes years. Therefore, as age advances, the risk of developing angina increases.
10- Male sex
Males are more liable to atherosclerosis and experience it at a younger age than women for two reasons. The first being the presence of male sex hormone (testosterone), which increases the level of LDL cholesterol, and the second is the absence of female sex hormones which have a protective effect against atherosclerosis.
Angina Types
The main types of angina are:
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- Stable angina
- Unstable angina
- Prinzmetal’s variant angina
- Microvascular angina
There are some other minor types, but they are incredibly rare compared to the above. Now, let’s take each one of them and discuss it in detail.
1) Stable angina
It is the most common type of angina and the most important cause of chest pain. It results from the narrowing of the coronary arteries -the main blood supply to the heart muscle- from chronic deposition of fat in their walls, causing plaques and decreasing the diameter of the vessels in a process known as atherosclerosis. The pathology of coronary artery narrowing is gradual and takes years to develop. The condition remains asymptomatic until the narrowing reaches the threshold at which it starts causing the characteristic anginal pain. This pain is a consequence of not meeting the oxygen supply requirements of the blood and may lead to ischemia. The patient can predict his or her attacks as they have specific “triggers” that include:
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- Physical exercise
- Emotional stress
- Cold exposure
- Heavy meals, especially consisting of fatty foods.
Attacks are usually brief (not more than 10 minutes) and are relieved by medications as nitrates and by rest. Since stable angina is a gradual process, symptoms tend to worsen over time, and the effort needed to cause symptoms become less until it reaches the level of occurring at rest.
2) Unstable angina
Unstable angina is the inevitable consequence of the stable type when the risk factors and the pathology are not controlled. It occurs due to progressive atherosclerosis and narrowing of the coronaries that aggravates the symptoms until they occur at rest, lasting longer than 10 minutes, becoming more severe, and not being relieved by rest or nitrates. The reason for this sudden narrowing is the blockage of an already narrowed artery or arteries by a blood clot.
Under normal circumstances, clots don’t form because the blood vessel’s wall is “smooth,” composed of perfectly lined cells of the vessel wall. However, in the case of unstable angina, the fatty plaques already present in the coronary arteries walls are “disrupted” or ruptured, giving blood platelets the needed “rough” surface to aggregate and form a clot.
Unstable angina is a medical emergency and a warning sign that a heart attack -medically known as myocardial infarction- is likely to follow. Thus, unstable angina is grouped into what is called “acute coronary syndrome” along with myocardial infarction. The only difference between them is the evidence of heart cells’ death, which is only present in myocardial infarction.
3) Prinzmetal’s variant angina
It is a rare condition and, contrary to the stable and unstable types of angina, Prinzmetal’s angina is not caused by atherosclerosis as a primary pathology. Instead, it is triggered by the “spasm” of coronary arteries that will suddenly cause a drop of blood supply to the heart. Attacks are acute and unpredictable. Triggers of this spasm include:
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- Smoking
- Cold exposure
- Emotional stress
- Cocaine use
- Other medications
They may also be triggered without a specific cause. Prinzmetal’s angina can occur in healthy or diseased coronary arteries by atherosclerosis, and is commonly associated with other conditions related to the spasm of other arteries in the body, as in the case of migraine headaches -where spasm of arteries in the brain is the leading cause- and Reynaud’s phenomenon (excessive spasm of your fingers’ arteries leading to a bluish discoloration and pain, more common in response to cold temperatures). Since both migraines and Reynaud’s are more common among females, Prinzmetal’s angina has a higher prevalence among females. The condition has a better outcome than unstable angina and is manageable by medications.
4) Microvascular angina
Microvascular angina is a type of angina where the narrowing occurs in the small branches of the main coronary arteries -hence the prefix “micro”- rather than the primary arteries like the previous types. It is characterized by chest pain that usually lasts for longer compared to stable angina, and takes a longer time to be relieved after rest or nitrates intake. Microvascular angina is diagnosed by exclusion of the other types through investigations and follow-up.
Angina Diagnosis
In the past few decades, the diagnosis of angina has become much easier and more reliable with the advent of modern methods that help both evaluate the severity of angina and have a potential curative effect as a step in many treatment options.
The diagnosis of angina -similar to most other diseases- consists of a gathering enough data for a good medical history, a thorough physical examination and targeted lab tests when they are needed. The physician will usually ask about the nature of symptoms including:
− Chest pain or discomfort: A typical anginal pain would feel like squeezing, burning, and less frequently stabbing just behind your breastbone (sternum) which might also be felt in your jaw, neck or left arm.
− When it starts and what aggravates or relieves it: A typical anginal pain would start and is usually aggravated by physical and sometimes emotional stress, but it might also be triggered by heavy meals and cold exposure and usually relieved by rest. An anginal pain that isn’t relieved by rest would point towards what is called “unstable angina”, a clinical condition with a greater risk that requires immediate investigations and more aggressive management.
− Risk factors for any coronary heart disease: It is important to investigate for risk factors affecting the blood supply to the heart, and they include: family history of the same or similar conditions, consumption of excessive fatty or sugary meals, lack of physical activity and smoking as well as alcohol consumption.
− Other heart related symptoms: Your physician will ask about other symptoms such as shortness of breath, excessive sweating, and effort intolerance or previous diagnosed heart conditions or operations.
The general examination
Afterwards, the physician will perform both a general examination and one focused on your cardiovascular function. The general examination includes:
♥ Measuring your weight and your body mass index (BMI): This is a measurement of your weight in relation to your height.
♥ Measuring your waist-to-hip ratio: This is a helpful measurement of abdominal obesity.
♥ Measuring your blood pressure and blood glucose level: These general examinations are mainly directed towards the identification of high risk groups rather than the disease itself. Stable angina tends to have a completely normal physical examination on presentation, and that’s why the physician usually performs other examinations to exclude additional causes of chest pain, as in muscle pain of your chest wall, which is characterized by being aggravated by breathing rather than effort itself, or heartburn from stomach problems that is usually related to meal frequency.
Investigations for the diagnosis of angina
1. Routine lab investigations:
They are performed when there’s already a high suspicion level that the patient may have angina pectoris, and they include: cholesterol and triglycerides levels, cardiac markers or enzymes to detect any damage that might have occurred. This is because damaged heart cells tend to “leak” their enzymes when they die, thereby increasing their level in the blood.
2. Stress ECG or electrocardiogram:
It is the most routinely used investigation for angina pectoris. A stress ECG measures the electrical activity of the heart, and has various patterns that reflect when the heart is deprived of all or some of its blood supply. The difference between a stress ECG and the ordinary ECG is the application of a physical – and less commonly chemical- stress on the heart muscle, such as running on a treadmill. Since angina pectoris occurs in episodes, a normal ECG performed between the attacks is likely not to show anything abnormal. Therefore, we need to simulate a stress condition to push the heart to its limits and help accentuate any present anginal electrical change.
3. Echocardiogram:
It is one of the most sensitive tests for the diagnosis of angina, and it consists of sound waves that have specific frequencies and wavelengths that “bounce off” and reflect after hitting tissues. This technique helps doctors visualize the anatomy of the heart and detect and abnormalities in the blood flow to the heart as in the case of narrowing of your coronaries. An echocardiogram may also be performed with the stress ECG to take advantage of the stress applied and determine more accurately any abnormality as well as to visualize the most vulnerable areas of this abnormality.
4. Computerized Tomography (CT) scan:
Although not done as routinely as the previous tests, a CT scan may be requested by your treating physician. It is like an X-ray of the heart but taken at multiple levels or “slices” and helps visualize any abnormal anatomy affecting the blood supply of the heart and any evidence of previous heart attacks that were severe enough to cause the death of a part of the heart, clinically known as myocardial infarction.
5. Cardiac MRI:
Similarly, a cardiac MRI helps visualize the heart anatomically and it is usually requested in some patients who can’t tolerate CT. This is the case of patients with allergic reactions against the contrast material that is usually injected during the CT scan.
6. Nuclear stress test:
This test involves the injection of a radioactive substance into the bloodstream, which is then detected by a special scanner that measures whether the cardiac muscles are taking enough of this radioactive substance -and hence blood- or not. Thus, when a portion of the heart isn’t taking enough of this substance, it means that this portion is “ischemic” or deprived of enough blood supply.
7. Coronary angiogram:
Coronary angiogram remains to be the best, but the most invasive of the previous tests. It is a traditional X-ray of the heart but requires the injection of a dye into the blood vessels of the heart through a catheter.
A catheter is a tube-like structure that is inserted through the blood vessels of your legs (the femoral artery or vein) and less commonly those of your forearm (the radial artery). Then, it goes up the blood stream to the aorta where it injects the dye to take an X-ray afterwards. If your coronary arteries are narrow or occluded, the dye will either stop at a certain site or become narrowed. A coronary angiogram is also a routine step prior to the placement of a “stent” for the treatment of both unstable angina and myocardial infarction or the injection of vasodilators or thrombolytic agents in some cases.
Angina Treatment
It is essential to know that angina is a treatable condition and that treatment modalities depend on both the type and the severity of the problem. They range from lifestyle modifications to emergency bypass surgeries. The main goal of treatment is to control the underlying pathology, relieve the symptoms, and prevent future cardiovascular events by controlling the risk factors, fixing the narrowing of the arteries by medications or anatomically by changing the pathology.
1) Lifestyle changes
Lifestyle modifications may be sufficient if your condition is mild and your symptoms are minimal. However, they are always required, even in the most severe forms of angina because they modulate the main risk factors and hence, work by preventing a recurrence. They include:
A. Weight control
The equation is actually simple: excess fat means excessive deposition of fat in your coronaries, which will aggravate their narrowing and, therefore, your condition.
B. Smoking cessation
There has never been a more significant correlation between a disease and a risk factor than there is between heart conditions and smoking. Smoking reduces oxygen delivery, favors clot formation and raises blood pressure. Studies have found that smoking cessation alone decreased the risk of death from coronary artery disease by 61% within 5 years.
C. Modifying your daily activity
Activities that precipitate angina should be detected thoroughly and performed slowly, on intervals, or stopped completely if needed.
D. Physical activity
Sedentary lifestyle is a significant risk factor for angina, and physical exercise has a cardioprotective effect. Thus, increasing your daily physical activity is always good, but it is important to consult your doctor about the type of exercise you need to do because some types of training might be too strenuous to your heart in your current condition.
E. Controlling your hypertension, diabetes, and hypercholesterolemia
Whereas diabetes increases fat deposition in your coronaries, hypertension “injures” the walls of your coronaries making them more susceptible to fat deposition and clot formation. At the same time, hypercholesterolemia increases the level of cholesterol fats in your bloodstream. Controlling these risk factors significantly improves the quality of life.
F. Decreasing alcohol intake
Excessive alcohol aggravates angina, precipitate anginal pain attacks, and interacts with many medications typically used by these patients, such as statins, which lower your cholesterol level, and warfarin, a blood thinner that helps preventing clot formation in your blood vessels.
G. Eating healthy food
Food rich in saturated fats and refined sugars should be avoided since they increase the level of LDL cholesterol or what we call “the bad cholesterol,” a molecule that favors cholesterol deposition in the coronaries.
2) Medications
As mentioned before, treatment is decided based on severity. In the case of stable angina, lifestyle changes and medications are usually sufficient to control the condition. These medications include:
A. Medications used during the attack (nitrates)
These dilate the coronary arteries supplying the heart muscle and therefore, increase the blood supply to the heart, relieving the attack within minutes. You should never self-medicate with nitroglycerin or other nitrates without consulting your treating physician, especially if you are using other medications for erectile dysfunction as Sildenafil (Viagra) or Tadalafil (Cialis), or if you are liable to hypotension.
B. Medications that lower blood pressure
They include ACE inhibitors and calcium channel blockers. They lower blood pressure by vasodilation (increasing the diameter of blood vessels) and the work the heart has to do to overcome such pressure, decreasing its oxygen demand and the incidence of angina. Calcium channel blockers also dilate the coronary arteries thus increasing the heart’s blood supply.
C. Beta-blockers
These medications decrease the heart rate and reduce the oxygen demand by the heart. They also prolong the time it takes for coronary arteries to fill, improving the blood supply to the heart.
D. Medications that lower blood cholesterol
The most commonly used class is statins, such as atorvastatin and simvastatin. They decrease the formation of cholesterol in the body, decrease its absorption, and help reabsorb cholesterol that’s been already deposited in the coronaries and other blood vessels, reversing the pathology.
E. Aspirin and other antiplatelets
These medications may be also prescribed by your doctor. They act by preventing your platelets from “sticking together” quickly and thus, decreasing the risk of blood clots.
F. Ranolazine
Ranolazine is a relatively novel drug used either as a substitute or complementary to beta-blockers and ACE inhibitors. It reduces the heart’s need for oxygen making the diminished blood supply more tolerable, thus preventing heart attacks.
3) Surgical and invasive options
Invasive options are usually needed in case of stable angina which is not relieved by rest nor controlled by medications. They offer a more permanent but invasive solution to the primary pathology of angina through bypassing the narrowing. They include:
A. Percutaneous intervention or (PCI)
PCI replaced open-heart procedures in many instances, decreasing the morbidity and mortality associated with it and improving patient’s outcome. It involves inserting a catheter, which is a thin tube-like structure, through your forearm or leg vessels. Then, the catheter goes up till reaching your coronaries at the site of narrowing. After that, the doctor will inflate a balloon to dilate the vessel. He may or may not leave a “stent.” A stent is a wire mesh-like structure that keeps the arteries open and wide to prevent the recurrence of narrowing and is usually “absorbed” into the wall of your artery. It is called “percutaneous” because it is done through a small incision over your arteries in your leg or forearm, without the need to have large incisions nor major surgeries.
B. Coronary artery bypass surgery/graft or (CABG)
It is another option for the management of unstable angina when a PCI fails, in cases of narrowing of multiple vessels, and when there’s a significant narrowing of a primary vessel. It involves bypassing the narrowed vessel or vessels using grafts taken from elsewhere in the body, thus creating a new “route” rather than trying to widen an existing one. Most grafts are taken from vessels of your calves (saphenous veins) or your chest (internal mammary artery) and rarely, your forearm (radial artery). It is an open heart procedure that carries some risks and thus, reserved for particular cases.