Heart disease can affect coronary arteries that feed the heart muscle, the heart's valves, the heart's electrical system, the heart muscle itself.
Coronary Artery Disease (CAD)
The coronary arteries supply a constant flow of oxygen-rich blood to the heart, which pumps almost 2,000 gallons of blood throughout the body each day. If plaque builds up in these coronary arteries, blockages can develop, reducing blood flow to the heart and causing symptoms ranging from mild chest pain to a heart attack, which can be fatal.+
The best way to deal with coronary artery disease, of course, is to prevent it. All of us should do everything we can to reduce our CAD risk factors.
For those who already have CAD, reducing these same risk factors becomes even more important, in order to slow the progression of the disease. In addition, several avenues are available for treating CAD, including drug therapy, surgical therapy, and angioplasty and stenting. The treatment of CAD always needs to be individualized, and optimal therapy depends on careful consideration of all the options, by both the doctor and the patient.
Depending on the number, severity and location of these obstructions, the physician may refer the patient for medical therapy, bypass surgery, or, if appropriate, may treat the patient directly, using catheter-based techniques. These options are discussed with the patient after the diagnostic catheterization.
Angioplasty and Stenting
Angioplasty is a procedure to open narrowed or blocked blood vessels that supply blood to the heart. These blood vessels are called the coronary arteries.
A coronary artery stent is a small, metal mesh tube that expands inside a coronary artery. A stent is often placed after angioplasty. It helps prevent the artery from closing up again. A drug eluting stent has medicine, when the stent is placed, the drug is released over time directly to the area most likely to reblock.
Coronary Artery Bypass Grafting (CABG)
Coronary artery bypass grafting is a type of surgery that improves blood flow to the heart. It's used for people who have severe coronary artery disease, also called coronary artery disease.
CABG is one treatment for severe coronary artery disease. During CABG, a healthy artery or vein from the body is connected, or grafted, to the blocked coronary artery. The grafted artery or vein bypasses (that is, goes around) the blocked portion of the coronary artery.
This creates a new passage, and oxygen-rich blood is routed around the blockage to the heart muscle.
As many as four major blocked coronary arteries can be bypassed during one surgery.
Valvular heart disease is any disease process involving one or more of the valves of the heart (the aortic and mitral valves on the left and the pulmonary and tricuspid valves on the right). Valve problems may be congenital (inborn) or acquired (due to another cause later in life). Treatment may be with medication but often (depending on the severity) involves valve repair or replacement (insertion of an artificial heart valve). Specific situations include those where additional demands are made on the circulation, such as in pregnancy.
Heart failure, also known as congestive heart failure, is a condition or a collection of symptoms in which the heart isn't pumping enough blood to meet the body's needs.
Heart failure usually develops slowly after an injury to the heart. Some injuries may include a heart attack, too much strain on the heart due to years of untreated high blood pressure, or a diseased heart valve.
Common causes of heart failure include:
- Coronary artery disease
- Previous heart attack (myocardial infarction)
- High blood pressure (hypertension)
- Valve disease
- Congenital heart disease (condition you are born with)
- Cardiomyopathy (enlarged heart)
- Myocarditis (infection of the heart)
Heart failure symptoms aren't always obvious. Some people in the very early stages of heart failure may have no symptoms at all. Others may dismiss symptoms like fatigue or shortness of breath as signs of growing older.
Sometimes, however, heart failure symptoms are more obvious. Because of the heart's inability to efficiently pump blood and supply your organs (such as the kidneys and the brain), you may experience a number of symptoms, including:
- Shortness of breath
- Swelling of the feet and legs
- Lack of energy, feeling tired
- Difficulty sleeping at night due to breathing problems
- Swollen or tender abdomen, loss of appetite
- Cough with "frothy" mucus or phlegm
- Increased urination at night
- Impaired memory
Some people are more likely than others to develop heart failure. No one can predict for certain who will develop it, but there are known risk factors. Being aware of the risk factors and seeing a doctor for early treatment are good strategies for managing heart failure. Heart failure risk factors include:
- High blood pressure (hypertension)
- Heart attack (myocardial infarction)
- Abnormal heart valves
- Enlargement of the heart (cardiomyopathy)
- Family history of heart disease
Only your doctor can tell if you have heart failure and how far the condition has progressed. Your doctor will review your medical history, including past and present illnesses, family history, and lifestyle. As part of your physical examination, the doctor will check your heart, lungs, abdomen, and legs to see if signs of heart failure are present.-
- To rule out or confirm the diagnosis of heart failure, your doctor may order one or several of these diagnostic tests:
- Electrocardiogram (ECG)
- Chest x-ray
- Exercise test (stress test)
- Cardiac catheterization
If you have heart failure, your doctor may also track your ejection fraction over time. Ejection fraction is defined as the percentage of blood that is pumped out of the heart during each beat. It's a key indicator of your heart's health and is frequently used by doctors to determine how well your heart is functioning as a pump.
If you have tachycardia, your heart may beat up to 400 times per minute. This can cause dizziness, lightheadedness, or a fluttering in the chest. An implantable cardioverter defibrillator continuously monitors your heart and delivers life-saving therapies to treat dangerously fast heart rhythms.
Tachycardia is a fast or irregular heart rhythm, usually more than 100 beats per minute and as many as 400 beats per minute. At these elevated rates, the heart is not able to efficiently pump oxygen-rich blood to your body.
Tachycardia can occur in either the upper heart chambers (atrial tachycardia) or lower heart chambers (ventricular tachycardia).
Causes of tachycardia include:
- Heart-related conditions such as high blood pressure (hypertension)
- Poor blood supply to the heart muscle due to coronary artery disease (atherosclerosis), heart valve disease, heart failure, heart muscle disease (cardiomyopathy), tumors, or infections
- Other medical conditions such as thyroid disease, certain lung diseases, electrolyte imbalance, and alcohol or drug abuse
- Emotional stress or drinking large amounts of alcoholic or caffeinated beverages
Symptoms of tachycardia include:
- Shortness of breath
- Sudden weakness
- Fluttering in the chest
Certain conditions can increase your risk of developing tachycardia:
- Coronary artery disease (atherosclerosis)
- Heart failure (poor pumping heart)
- Heart attack (myocardial infarction)
- Congenital heart defects (condition you are born with)
- Inflammatory or degenerative heart conditions
- Chronic lung disease
What is a seizure?
A seizure is a sudden, involuntary change in behavior, muscle control, consciousness, and/or sensation. A seizure is often accompanied by an abnormal electrical discharge in the brain. Symptoms of a seizure can range from sudden, violent shaking and total loss of consciousness to staring into space, altered vision, and difficult speech. Approximately 10 percent of the population will experience a single seizure in their lifetime. (Source: Epilepsy Foundation)
What is syncope or fainting?
Syncope (sing'-koe-pee), the medical term for fainting, is the sudden loss of consciousness and physical collapse due to lack of blood and oxygen to the brain. Syncope can occur with or without warning, as an isolated event, or frequently over time. Syncope is sometimes characterized by symptoms that mimic an epileptic seizure such as confusion muscle twitching, shaking, convulsions and physical collapse.
Is a seizure the same as syncope?
No, but it can be very difficult to distinguish between an epileptic seizure and syncope. Syncope may result in movements or behaviors that mimic seizures. The difference is, an epileptic seizure produces a brief disturbance in the normal electrical functions of the brain, while syncope is caused by a reduction in blood flow carrying oxygen to the brain. A seizure can sometimes accompany a syncope episode and syncope can sometimes accompany a seizure.
What causes syncope?
Syncope usually occurs when the brain does not receive enough blood and oxygen. Some causes of syncope are relatively harmless, and others can be life threatening. Cardiovascular causes of syncope can be among the most serious. One of the most common heart-related causes is an abnormal heart rhythm (also known as an arrhythmia). In these cases, the heart beats too slowly, rapidly, or irregularly to pump enough blood to key parts of the body, including the brain.
Other causes of syncope include some neurological disorders, psychological conditions, and obvious situations such as standing up too fast or being in a hot room. These factors contribute to making the cause of syncope difficult to diagnose.
How is syncope treated?
If syncope is caused by an abnormal heart rhythm, therapy options may include medication, an implantable device (such as a pacemaker or implantable cardioverter-defibrillator (ICD), or corrective surgery, such as catheter ablation.
With appropriate treatment, a person suffering from cardiovascular syncope can often resume normal activities without fear of having another episode. Treatment may eliminate the syncope and may also treat the potentially life-threatening cardiovascular cause, thereby improving a person's overall quality of life.
What causes seizures or seizure-like episodes?
Although the cause cannot always be identified, there are many different conditions that can cause seizures or seizure-like episodes. These can be grouped into four categories: neurological, psychological, cardiovascular, and other causes.
Neurological conditions stemming from infections, brain injury, tumors, stroke, etc. These most often lead to changes in brain electrical activity and are sometimes referred to as "epileptic seizures."
- Cardiovascular conditions due to heart rhythm abnormalities, blocked vessels, blood pressure irregularities, etc. These can lead to symptoms that are almost identical to seizures from neurological conditions.
- Psychological conditions including panic attacks, hysteria, emotional distress, etc. Seizures caused by psychological conditions are often referred to as psychoseizures, pseudoseizures, or non-epileptic seizures.
- Other causes can be related to metabolism (electrolyte imbalance, low blood sugar), diabetes, a high fever, etc.
What is the most efficient way to determine the cause of seizure-like episodes?
Correctly evaluating the cause of recurrent seizures or seizure-like episodes requires the collaboration of several medical specialists beyond the general practitioner, internist, or pediatrician. These specialists may include a neurologist or epileptologist if a neurological cause is suspected. If a cardiovascular cause for seizure-like episodes is suspected, a cardiologist or an electrophysiologist (a cardiologist with special training in diagnosing and treating abnormal heart rhythms) should be consulted. If a psychological cause is suspected, psychiatric evaluation may be required.
What is the risk of having a seizure?
According to the Epilepsy Foundation, approximately 10 percent of the U.S. population will experience seizure-like symptoms in their lifetime. That is, about twenty-five million Americans (one in every ten) have had, or will have, a seizure at some point in their lives.
In the United States, the Epilepsy Foundation estimates that approximately $1.7 billion is spent in direct costs on patients with epilepsy and seizures.
What is the risk of having syncope?
Thirty percent of the U.S. population will faint during their lifetime, at a cost of more than $1 billion annually. (Source: HCIA, Inc., October, 1996-September, 1997)
What is a pacemaker?
Pacemakers are implantable medical devices that are prescribed for people whose hearts are beating too slowly or irregularly. A pacemaker stimulates the heart muscle with precisely-timed discharges of electricity that cause the heart to beat in a manner quite similar to a naturally occurring heart rhythm.
A pacemaker consists of:
- A pulse generator with battery and circuitry providing electrical energy and timing;
- A pacing lead - an insulated wire that carries electrical impulses to the heart and information about the heart’s natural activity back to the pulse generator; one or two leads are used depending on the type of pacemaker prescribed.
Why might someone need a pacemaker?
The human heart’s own natural pacemaker is called the sinus node. It produces impulses that travel through electrical pathways in the heart and cause the heart muscle to contract and pump blood as it’s needed by the body. Sometimes this natural mechanism becomes diseased so that impulses are irregular - too slow, too weak – or its impulses may be blocked by other disorders. Bradycardia is the name for a group of diseases in which the heart beats too slowly to support the circulatory needs of the body.
If this happens, the person may feel dizzy, weak, or just very tired. An artificial pacemaker may then be used to restore a consistent flow of proper electrical impulses, thus improving blood circulation and restoring a general feeling of well being to the patient.
What are the different types of pacemakers?
Pacing therapy is diverse because the underlying heart conduction disorders that result in rhythm disturbances are different. Following are brief descriptions of the types of pacemakers available today:
- Single-chamber pacemakers typically use one pacing lead placed either in the right atrium or the right ventricle for atrial or ventricular pacing.
- Dual-chamber pacemakers typically use two pacing leads, one placed in the right atrium and the second placed in the right ventricle; the electrical pulses delivered to the heart are timed so that the atria and ventricles are beating “in sync” with each other.
- Rate responsive pacemakers use a special sensor (or combination of sensors) to recognize body changes and adjust the patient’s heart rate to speed up or slow down as needed.
How are pacemakers implanted?
The most common implantation method is the endocardial approach, which is relatively simple and can be performed under local anesthesia. For this method, the pacing lead is inserted into the heart via a vein. The pulse generator is typically placed under the skin in the upper chest area near the collar bone.
How are pacemakers adjusted after implant?
Much like a small computer, the programmer is used by the physician to externally adjust the pacemaker to meet the patient’s needs. It sends signals to, and receives signals from, the pulse generator on radiofrequency waves - without surgery.
Are pacemakers safe around household appliances?
Properly maintained electrical household items are unlikely to interfere with pacemaker operation. These include:
- microwave ovens
- televisions, radios, video games, CD players, and stereos
- electric blankets and heating pads
- toasters, blenders, food processors
- hair dryers and shavers
- large appliances such as washers, dryers, electric stoves, vacuum cleaners
- outdoor equipment such as lawn mowers, leaf blowers, and snow blowers
May patients use cellular phones?
Cellular phones are unlikely to interfere with pacemaker operation if proper precautions are followed:
- A distance of at least six inches should be maintained between a cellular phone and a pacemaker.
- The cellular phone should be held to the ear opposite the side of the body in which the pacemaker is implanted.
- The cellular phone should not be carried in a pocket on the same side as the implanted pacemaker.
Are screening devices a concern?
Airport screening devices are unlikely to affect pacemaker operation, but they may detect the metal housing of the device and set off the security system. To obtain clearance, patients should show their pacemaker identification card to airport personnel, request scanning with a hand-held screening device, or request a hand search.
When encountering anti-theft systems in stores and libraries, patients should walk normally through the detectors and not linger in adjacent areas.
Is equipment in the work environment safe for pacemakers?
Office and shop equipment are unlikely to interfere with pacemaker operation if they meet current electrical safety standards. These include:
- computers, electric typewriters
- copying machines, fax machines
- small wood and metal working shop tools
Pacemaker patients who work in a heavy industrial environment should ask their physicians about potential risks.