Get Adobe Flash player

Main Menu

Heart Attack and Cardiac Disorders

(40) Heart Attack and Cardiac Disorders


MAYO CLINIC - Coronary angioplasty and stents


How do I prepare for coronary angioplasty?

Unless you were already hospitalized, you would be admitted to the hospital on the day of the procedure or on the night before. You would be told not to eat or drink anything after midnight (at least 6-8 hours before the procedure). When the hospital staff were certain that you understood the procedure (its purpose, potential benefits, and possible risks), you would sign a consent form.

Before the procedure, after routine blood tests, the staff would perform an electrocardiogram (ECG) and a chest x ray. They would clean and shave your groin area (or your arm area in some cases) to prevent any infection before inserting the catheters (also as a part of the procedure). They would insert a small intravenous needle (IV line) into an arm vein for administering fluids and medications as needed. It would be a good idea to empty your bladder as completely as possible before the procedure starts. (Of course, a bedpan or urinal would be available during the procedure).

What is a coronary stent, and when is it used?

A coronary stent is a relatively new device implanted permanently in the diseased coronary artery to keep the diseased coronary artery open during and after coronary angioplasty. It is used in up to 60 to 80% of patients who undergo PTCA. The stent is a fine slotted, metallic coil, tube, or mesh structure inserted into the diseased coronary artery at the site where PTCA procedure dilated the blocked or narrowed coronary artery. The stent can reduce various complications, such as a new heart attack or a restenosis of the coronary artery. Research has shown that the restenosis rate after a simple coronary angioplasty without a stent is 30 to 40%, but the restenosis rate is reduced to 20% when a stent is used. Thus, the stent is used practically for every patient who undergoes coronary angioplasty.

The coronary stent is mounted on a balloon catheter and delivered to the site of severe narrowing or blockage of the coronary artery. When the balloon is inflated, the stent expands and is pressed against the inner wall of the diseased coronary artery. After the balloon is deflated and removed, the coronary stent permanently remains in place to prevent restenosis.

Several different kinds of stents are produced in various designs, but the most commonly used stent is the Palmaz-Shatz stent. This stent is a small, slotted, stainless-steel tube about half an inch long, and it weighs as little as a straight pin. It is as narrow as a piece of thin noodle. One or more coronary stents may be used in the coronary artery when the narrowed or blocked segment of the artery is long. New tissue will slowly grow over the stent within a few weeks and will completely cover the stent.

What medications are commonly used during and after coronary angioplasty?

Restenosis of the coronary artery during or shortly after a successful coronary angioplasty is often (but not always) due to blood clots. Doctors frequently use anticlotting agents (medications to prevent blood clots), such as aspirin, heparin, coumarin, or combinations of these drugs, during and after the coronary angioplasty to prevent restenosis. Actually, aspirin is found to be more effective than heparin for this purpose.

New anticlotting agents, such as tirofiban or clopidogrel, may be effective in preventing restenosis when they are administered in combination with heparin or aspirin. However, in some cases, restenosis of the diseased coronary artery cannot be prevented by using the above-mentioned anticlotting drugs during or after angioplasty. That’s because restenosis in some cases is due to unknown causes.

What are the potential risks involved with coronary angioplasty?

The risks from coronary angioplasty are generally minimal, and its significant benefits usually outweigh the risks in treating heart attack patients. Potential risks involved with coronary angioplasty may include tearing or cracking of the coronary artery lining, which might close the treated artery, or cause a new heart attack or stroke or even (rarely) death. Because of such risks from coronary angioplasty, a cardiac surgical team must stand by during an angioplasty.


(41) Heart Attack and Cardiac Disorders

Cardiovascular diseases

Heart attack in 3d animation

What Is a Heart Attack?

Heart Attacks and Heart Disease


What is a coronary artery bypass graft, and when is it used?

A coronary artery bypass graft (CABG) is the major cardiac surgery performed most commonly in America and in all other civilized countries worldwide. CABG may be performed as an emergency operation, but it is performed more commonly as an elective surgery. Surgeons perform it when coronary angioplasty or thrombolytic therapy is not successful or is not appropriate. When CABG is scheduled (rather than as an emergency surgery), they usually do this a few days later to allow recovery of the heart muscle. A recent study showed that 1-year risk of death is reduced by more than 40% when coronary angioplasty or CABG is performed within 14 days after the onset of acute heart attack. The PTCA is initially successful in more than 90% of cases.

A CABG makes a bypass (detour) to reestablish blood circulation around the blocked segment of the coronary artery. Most commonly, a saphenous vein obtained from the leg is installed as a bypass vessel so that blood flow around the blockage from the aorta (the largest arterial trunk) to the coronary artery will be established. Less commonly, one or both internal mammary arteries (arteries in the chest wall, normally arising from branches of the aorta) are used for a CABG.

Doctors commonly perform a CABG to relieve a blocked left main coronary artery; a diffusely narrowed or blocked coronary artery; a disease involving multiple coronary arteries; and poor function of the left ventricle. In addition, a CABG also helps to overcome significant technical difficulty during PTCA, when PTCA is unsuccessful, and when there are serious complications during PTCA. Such complications might include rupture of the coronary artery, worsening of the blockage, and the occurrence of a new heart attack.

After a CABG, you would stay in the hospital for 1 week. You would need about 3 weeks for full recovery.

Is there an age limit or gender difference for CABG?

A coronary artery bypass graft is usually recommended for adults up to the age of 75 years. However, some older adults (80-85 years old) underwent CABG recently with successful outcomes. The outcome of CABG among women seems to be less favorable than that among heir male counterparts. That’s due to various reasons, such as some technical difficulty during CABG and the delayed diagnosis of coronary artery disease among women.

Are other kinds of heart surgery performed for heart attacks?

When any major complications of heart attack occur, a variety of heart surgeries might be necessary. In the event of mitral regurgitation (leaking back of blood flow from the left ventricle to the left atrium because of mitral valve dysfunction, physicians would replace the mitral valve with an artificial heart valve. When an acute heart attack produces a ventricular septal defect (formation of a hole in the ventricular septum between two ventricles, a surgeon would repair the hole immediately.

When a major complication, such as congestive heart failure (markedly diminished pumping action of the heart), persists or deteriorates in spite of all available therapy, you would need transplantation of a new heart or an artificial heart.

What is an artificial pacemaker, and when is it used?

When medications and varied medical or surgical treatments are not effective or appropriate, the resolution of certain medical conditions requires electrical treatment. One of two major electrical devices or methods is an artificial pacemaker. The other is the use of electrical shocks. An artificial pacemaker is a small, battery-operated device that regulates your heartbeat by imitating your natural heart rhythm arising from the sinus node (your natural pacemaker).

Some artificial pacemakers are permanent units (internal) implanted in the chest; others are temporary (external) units. Most artificial pacemakers have a sensing device that turns off when your natural heart rhythm is faster than the preset desired heart rate, and it turns back on when your heart rate becomes slower than that preset rate.

This type of artificial pacemaker is called a demand pacemaker. At present, almost all pacemakers are manufactured as demand pacemakers. The artificial pacemaker consists of two parts: the pulse generator and wires (insulated leads). The pulse generator is a small metal “can” that contains a battery and electrical circuitry (a computer). They regulate the rate of electrical impulses sent to your heart. The pulse generator is implanted in your chest, just below your collarbone in most cases. However, for cosmetic reasons, physicians can implant the pulse generator elsewhere (e.g., in the area between the upper chest wall and arm, or the armpit).

Newer models are much smaller and lighter than older models. The smaller models weigh less than an ounce and are about the size of three silver dollars sandwiched together. Their battery life is generally 6 to 7 years, but batteries may operate for up to 10 to 12 years. The pulse generator must be replaced periodically before the pacemaker batteries wear out.

A surgeon threads the pacemaker wires (insulated leads) through a large vein and into the heart, and these flexible wires are connected to the pulse generator. Thus, these wires deliver the electrical impulses from the pulse generator to the heart. Managing various slow heart rhythms primarily requires an artificial pacemaker, particularly for significant symptoms, such as dizziness and near-syncope or syncope, associated with these abnormal rhythms. Occasionally, treatment of advanced congestive heart failure (markedly diminished pumping action of the heart) also requires an artificial pacemaker.

Certain medical conditions require the use of an artificial pacemaker. For example, in the sick sinus syndrome, your natural pacemaker (the sinus node) is unable to produce sufficient heart impulses; that creates a very slow and unstable heart rhythm. In this disorder, slow heart rhythm often coexists with components of very rapid rhythms, such as atrial fibrillation or ventricular tachycardia. That leads to a combination of slow and rapid heart rhythms (called bradytachycardia.

In another condition, heart block (AV block), the interruption in conducting your heart impulse to your ventricles (lower chambers) causes a very slow heart rhythm. This interruption is the result of a block in the conduction system, commonly in the AV node.

Physicians may use biventricular pacemakers in some cases of advanced congestive heart failure. That’s the case when all available medications are not effective enough to relieve congestive heart failure. Biventricular pacemakers stimulate both the right and the left ventricles in a coordinated fashion so that the pumping action can be improved.

Are different pacing methods used?

In the past, all older artificial pacemakers were designed to set the pacing rate (and only one rate) to stimulate the heart, regardless of the patient’s needs and the heart’s functions. At present, however, almost all newer pacemakers are manufactured as demand pacemakers (it functions only when needed). In addition, most pacemakers are “rate-adaptive.” That means that they can be programmed to adjust the pacing rate to your activity level, mimicking your natural heart rhythm. The newer models can meet different pacing needs, depending on where the pacing leads are directed and the method of programming the pulse generator (computer).

In atrioventricular (AV) sequential pacing, the atria (upper chambers) and the ventricles (lower chambers) of your heart are paced sequentially, as the name of the pacing method indicates. In AV sequential pacing, the location of the pacemaker leads allows them to sense your heart’s activity and pace as needed: first in the atria and then in the ventricles, sequentially.

Dual-site atrial pacing is still in research. In this type of pacing, the pacemaker programs the leads to stimulate both the right and left atria (both upper chambers).

This type of artificial pacing may reduce episodes of atrial fibrillation (an irregular and usually rapid heart rhythm arising from upper chambers.

Biventricular artificial pacing stimulates both the right and left ventricles of your heart. Medical researchers consider this pacing method to be beneficial in improving the pumping action of the heart in patients with advanced congestive heart failure. Currently, all implantable defibrillators (used to shock a heart back into normal rhythm after sudden cardiac arrest or ventricular fibrillation) include artificial pacemaker functions.

Surgery for artificial pacemaker implantation usually requires no more than an overnight hospital stay. In most cases, local anesthesia is used. Before you’re discharged from the hospital, doctors program your artificial pacemaker to fit your heart’s needs. You would return after several months to allow your doctor to make more detailed adjustments to the pacemaker settings.


Ventricular septal defect - hole (abnormal communication) in the muscle wall between the ventricles, a common form of congenital heart disease and possibly caused by a heart attack; a life threatening complication.

Artificial pacemakers can be programmed to adjust the pacing rate to your activity level, mimicking your natural heart rhythm.


(44) Heart Attack and Cardiac Disorders

How to use an AED, Automatic External Defibrillator

Automated external defibrillators: Do you need an AED?

What Is an Automated External Defibrillator?


What is an automatic external defibrillator, and who needs it?

Patient comment:

If you are considered to be a high-risk patient after recovering from a heart attack, it is an excellent idea to keep an automatic external defibrillator (AED) in your home, especially when you had suffered from several episodes of cardiac arrest in the past. The AED is relatively easy to learn how to operate for anybody, and the device is not too expensive.

An automatic external defibrillator (AED) is a portable defibrillator that can deliver an electrical shock to halt ventricular fibrillation (very rapid, chaotic, and ineffective heart rhythm arising from the lower heart chambers). The AED is a small portable defibrillator that any lay person can easily operate. It’s used before you reach the hospital emergency room (ER). Because ventricular fibrillation must be stopped within a few minutes, an AED can prevent sudden death if used immediately.

Most ambulance teams carry an AED, as do many police and fire rescue units. In addition, AEDs are available in reputable commercial airplanes and various public places, such as sports arenas, large music halls, large international airports, and convention auditoriums. In addition, keeping an AED is highly recommended in private homes for high-risk patients recovering from recent heart attacks. High risks would be seen in those who have had multiple heart attacks, blockage of many coronary arteries, cardiac arrest (ventricular fibrillation), or massive heart muscle damage.

Such risks also would include the likelihood of future heart attack, cardiac arrest, or a history of serious complications.

What is an implantable cardioverter-defibrillator, and who needs it?

Recently, the use of implantable cardioverter-defibrillators (ICDs) has been increasingly popular among high-risk heart attack victims. Such a device can prevent sudden death from ventricular fibrillation.

The ICD is a small electronic device that can deliver an electrical shock automatically when you develop ventricular fibrillation or ventricular tachycardia (rapid and regular rhythm arising from the ventricles). New ICDs provide overdrive pacing to convert sustained ventricular tachycardia and backup pacing for very slow heart rhythm (bradyarrhythmia). The ICDs also provide various other sophisticated functions: noninvasive electrophysiologic (EP) testing and storage of detected arrhythmias.

An ICD consists of two main parts: a pulse generator and leads. The pulse generator is a small lightweight metal case (about the size of a pager or a small match box) containing a small computer and a battery. A surgeon implants the pulse generator under the skin near your left collarbone, usually under general anesthesia. (Some medical centers use local anesthesia and use general anesthesia for shock testing.) The leads are insulated, flexible wires placed in your heart, and they carry electrical energy from the pulse generator to your heart. The surgeon threads most leads from the ICD through one of your veins to the inside of your heart.

The surgery to implant the ICD takes about 2 to 3 hours. Most patients stay in the hospital for 1 to 2 days after the surgery. The cardiologist carries out an electrophysiologic study (EPS) before discharging you to check the device and to evaluate how your ICD is functioning. The cardiologist usually performs a post surgery EPS and subsequent studies noninvasively through the device via radio waves.

The cardiac team programs and designs each ICD specifically for individual need by performing an EPS before, during, and after the ICD surgery. In that way, your device can retain specific and individualized instructions about your needs. Programming of an ICD uses radio waves, and adjustment of the device can be made externally. An ICD monitors the electrical activity of your heart continuously on a beat-to beat basis, and it can effectively terminate ventricular fibrillation or tachycardia within seconds.

About 400,000 deaths occur each year in America from sudden cardiac arrest caused by ventricular fibrillation. Most patients who experience this are high-risk heart attack victims. High risk in heart attack victims has been identified previously (see the discussion of automatic external defibrillators). In particular, heart attack victims who survived cardiac arrest belong in the high-risk category. As has been stated, all patients with multiple heart attacks, blockage of multiple arteries, massive heart muscle damage, and major complications are at high risk.

What will I feel after an ICD implantation, and what should I do if I receive an electrical shock?

After your ICD implantation, like most patients you will experience some pain and stiffness around the incision area; it may remain swollen and tender for a few weeks. Your surgeon will prescribe some pain medications, but you should avoid any pain medication containing aspirin. If you respond like most patients, you will be discharged from the hospital 1 to 2 days after the surgery. Then you should receive full instructions regarding the functions of your ICD, care of the incision area, physical activity, medications, and various precautions and follow-up visits. Before you are discharged, you will be given an ICD identification card. It contains all necessary information about your ICD: Instructions in case of an emergency, your doctor’s name and phone number, and so forth. You should carry this card at all times.

A range of feeling is possible when your ICD is working for rapid heart rhythms. If you developed a rapid heart rhythm, the leads immediately would transmit signals to your ICD to initiate the electrical shock treatment. If the rapid heart rhythm were mild and short in duration, short and rapid electrical pulses would be delivered in a predetermined (programmed) pattern to restore your normal heart rhythm. Such electrical pulses are mild and, like most patients, you wouldn’t feel them.

If a very fast abnormal heart rhythm continued, however, your ICD would deliver a much larger electrical shock to terminate the rapid rhythm. Large electrical shocks will be painful, but the discomfort lasts only a fraction of a second. The discomfort is often described as a “kick in the chest.”

If you receive an electrical shock, you should sit down or lie down in whatever position you feel more comfortable. A family member or a friend should stay with you throughout the incident. If you were found unconscious, a family member or a friend should call an ambulance and your physician. If the electrical shock seems to be ineffective and the rapid heart rhythm continues, someone should inform your doctor immediately. Dialing Ambulance urgency might be necessary if you needed any urgent treatment. If your ICD seems to be working properly in response to a rapid heart rhythm, calling your physician immediately isn’t necessary. Your ICD will record and save all necessary information regarding the electrical shock therapy events. The information retrieved from the ICD is very important in evaluating your clinical conditions, the nature of your abnormal heart rhythms, and the effectiveness of your ICD. Thus, medical staff can adjust or reprogram your ICD if necessary to improve its effectiveness.


Automatic external defibrillator (AED) - portable defibrillator that can deliver an electrical shock to stop ventricular fibrillation.

A large shock is often described as a “kick in the chest.”

Keeping an AED is highly recommended in private homes for high-risk patients recovering from recent heart attacks.




(42) Heart Attack and Cardiac Disorders

What Is a Pacemaker and How Does It Work? (Video)

Definition of Artificial pacemaker

Artificial Pacemaker


What are the limits and risks of artificial pacemaker functions?

If you receive an artificial pacemaker implantation, you should carry a wallet ID card showing information about your pacemaker. That’s because some equipment used by doctors and dentists can affect your artificial pacemaker functions and may cause it to malfunction. You will also need to show this card when traveling through airports, as the security equipment used to screen passengers should not be used on people with pacemakers.

Many surroundings and devices do not interfere with the function of your artificial pacemaker. They include CB radios, electric drills, electric shavers, electric blankets, heating pads, metal detectors, microwave ovens, TV transmitters, remote control TV changers, and cellular phones (less than 3 watts). Dental equipment does not appear to interfere with the pacemaker functions, but you might may feel an increase in pacing rates during dental drilling.

Electrical shock treatment (electroconvulsive therapy) for certain mental disorders does not appear to interfere with pacemaker functions. Likewise, diagnostic radiation (e.g., chest x ray) appears to show no interference in pacing functions. However, therapeutic radiation (e.g., treatment for certain cancers) may interfere with pacemaker circuits.

Magnetic resonance imaging (MRI) may interfere with your pacemaker functions. Therefore, you should discuss possible risks and benefits with your doctor before undergoing an MRI procedure. Research has shown, however, that radiofrequency (RF) ablation is safe for pacemaker function. RF is a special electrical treatment to manage a variety of arrhythmias (abnormal heart rhythms).

Performance of lithotripsy, a noninvasive treatment to destroy kidney stones, is safe for most pacemaker wearers. However, this treatment may interfere with certain kinds of pacemakers implanted in the abdomen. Also, transcutaneous electrical nerve stimulation to manage acute or chronic pain may interfere with pacemaker function in certain models.

By and large, you should discuss the safety of and possible interference with your pacemaker’s functions with physicians or dentists before the use of any medical device or equipment. Pacemaker implantation is a simple procedure involving little risk, and complications are rare.

Nevertheless, possible risks and complications do exist. For example, displacement of the pulse generator or the pacemaker wires (insulated leads) can cause problems. Such events as tearing or perforation of the vein or arterial wall or of your heart itself; puncture of the lungs, which would cause your lung to collapse; and blood clotting or air bubbles in your veins could lead to major medical problems. Other events that would affect your pacemaker include infection or nerve damage at the incision site, bleeding or severe bruising, or even malfunction of your artificial pacemaker itself.

What kind of care is necessary after a pacemaker implantation?

After having an artificial pacemaker implanted, every patient requires certain follow-up care. By and large, you can carry out all daily activities without limitation, but you should be familiar with your pacemaker. You need to understand certain precautions and possible risks after receiving a pacemaker.

You should carry a pacemaker ID card at all times; it should contain important information regarding your pacemaker. You would show your ID card to any doctor or dentist or other medical professional during each visit. It’s also a good idea to show the ID card to security personnel (e.g., in airports) as needed. Medical personnel can monitor your pacemaker’s functions and transmit them via the telephone using a special telephone transmitter. They connect the transmitter to wristbands on each of your arms, then place the telephone receiver on the transmitter and hold a special magnet over the pacemaker. A specially trained technician on the other end of the phone line checks your heart rate, heart rhythm, pacemaker battery level, and pacemaker functions. The pacemaker check-up via telephone transmitter can be carried out at the doctor’s office or at a pacemaker clinic.

Several times a year, you should have a medical checkup at your doctor’s office or at a pacemaker clinic. Almost all university or teaching hospitals have a special pacemaker clinic that specializes only in patients with permanent pacemakers. During each visit, technicians check the battery level and functions of your pacemaker and can adjust your pacemaker’s settings as needed. The pacemaker pulse generator should be replaced every 6 to 10 years, and the leads may have to be replaced occasionally. The pacemaker clinic also can perform the pacemaker check-up via a telephone transmitter.

You should take certain precautions after receiving your pacemaker. You must inform your physician immediately if any troubling symptoms or signs occur. For instance, you might notice the reappearance of symptoms that surfaced before your pacemaker was implanted. Or you might feel dizziness, near-syncope or syncope, shortness of breath, marked weakness, or any other symptoms related to heart disease. Additionally, you might develop fever or chills (or both), a very rapid or very slow heart rhythm (with or without palpitations), pain, infection, swelling, or bleeding in the area around your pacemaker, or a swelling of the arm near the incision site. It is vitally important to report any such irregularity at once.

What is electrical shock treatment, and who needs it?

There are several ways to manage a variety of cardiac arrhythmias (usually very rapid heart rhythms) with electrical energy. One such process is emergency electrical shock treatment (use of a defibrillator) for cardiac arrest due to ventricular fibrillation (very rapid, chaotic, and ineffective heart rhythm arising from the ventricles). Another is electrical shock treatment of rapid heart rhythms that don’t respond to drugs, such as atrial fibrillation (rapid and irregular heart rhythm arising from the upper chambers). Other devices are automatic external defibrillators (AEDs) and implantable cardioverter-defibrillators (ICDs).

Certain drug-resistant rapid heart rhythms require the use of catheter ablation (a nonsurgical technique that destroys parts of the abnormal conduction pathway causing the arrhythmia).

Emergency defibrillation is only a life-saving measure to treat ventricular fibrillation, and the electrical shock should be delivered within 4 minutes from the onset of arrest (ventricular fibrillation). If administered after that, it usually will not prevent a fatal outcome. Delay of shock treatment for more than 4 to 5 minutes often produces permanent brain damage, even if the heart rhythm returns to normal later. Termination of ventricular tachycardia (very rapid and regular rhythm arising from the lower chambers) also often requires emergency electrical shock treatment. This is especially true if medications are not effective and the arrhythmia is life-threatening. Treatment of cardiac arrest in heart attack victims usually calls for cardiopulmonary resuscitation (CPR) coupled with electrical shock treatment.


Radiofrequency (RF) – ablation special electrical treatment to manage a variety of rapid heart rhythms.

Lithotripsy - noninvasive treatment to destroy kidney stones.

You should discuss the safety of and possible interference with your pacemaker’s functions with physicians or dentists.

You should visit your doctor or a pacemaker clinic several times a year.

Inform your physician immediately if any troubling symptoms or signs occur.



(45) Heart Attack and Cardiac Disorders

British Heart Foundation - Watch Your Own Heart Attack TV advert

Heart attack

Warning Signs of a Heart Attack

Heart Attacks and Heart Disease


What follow-up care and precautions should I take after I have an ICD implantation?

You should have close communication with your private physician after your ICD is implanted. Before being discharged from the hospital with your ICD, you will receive specific instructions on when to call your physician (or specially trained cardiac nurse).

Such instructions would specify calling within 24 hours of receiving an electrical shock; after two or more electrical shocks are received back to back; or if you felt any serious symptoms (e.g., dizziness, near syncope) from rapid heart rhythm lasting longer than 2 to 3 minutes.

Additionally, your instructions would tell you to call before scheduling any surgical or dental procedures and before scheduling any travel or moving to another location.

Naturally, you would call if you had any questions regarding your ICD, medications, or physical activities. Additional precautions to follow during the first few weeks after your ICD implantation are to avoid lifting anything heavier than 5 to 10 pounds, vigorous exercise or contact sports, and pushing, pulling, or twisting motions and to limit arm movements that may affect the electrical lead (wire) system. Also, you should keep cellular phones at least 6 inches away from your ICD and stay away from magnetic fields, such as high-voltage or strong electrical currents. You should avoid wearing any tight clothing that may irritate the skin over your pulse generator.

You should inform your physician of any signs of infection at the incision site or fever above 100°F. Finally, if any medical or dental care is needed, you should inform all medical and dental staff involved regarding your ICD. Implantation of your ICD requires periodic medical checkups to make certain that the ICD has been effective in halting all rapid heart rhythms. You should schedule follow-up visits several times a year at your doctor’s office or at a specially designed clinic dealing with ICDs. During such follow-up visits, medical personnel would use a programmer to guarantee that your ICD detects and treats rapid heart rhythms properly.

The programmer also can retrieve various medical information stored in the memory of your ICD. The medical information includes the events of any rapid heart rhythms to compare with your symptoms and your ICD’s effectiveness in handling such events.

Your ICD might need reprogramming according to changes in your medical condition and the effectiveness of the device for any rapid heart rhythms, particularly for life-threatening arrhythmias.

You need to replace your ICD’s battery every 5 to 8 years as well as the entire generator because its battery is sealed inside. Its battery life depends on the number of electrical shocks and the electrical energy used for stopping rapid heart rhythms. You should have the medical staff test the electrical leads and replace them as needed.

Resuming your daily activities should be gradual, according to your medical condition and your physician’s specific instructions. You should avoid driving a car for at least 6 months after being discharged from the hospital. The reason for this is the risk of ventricular arrhythmias (rapid heart rhythms from the lower chambers and not the risk of a problem in the ICD itself. Many patients who experience ventricular arrhythmias may need to avoid driving even after 6 months. Remember that you may develop dizziness, near-syncope, or syncope when ventricular arrhythmias occur. When you experience serious symptoms, you should have your physician evaluate you immediately, and your ICD may need reprogramming.

The natural increase in heart rate during sexual activity should not cause the ICD to deliver an electrical shock. If the ICD delivers an electrical shock during sexual activity, however, you should inform your physician immediately, because your ICD may need reprogramming.

If you schedule any travel, you should consult your physicians beforehand for proper instructions. You should request the name of a cardiologist and hospital in the area (other states or countries) to which you plan to travel. You are highly urged to carry a copy of medical records whenever you schedule an extended trip (longer than 1 month).

You should resume daily activities gradually. They may include walking, swimming, bicycling, bowling, gardening, cooking, golf, tennis, and returning to your previous job (desk job). You should refrain from such sports for the first 4 weeks, however, and any physical activity or emotional stress that may cause a very rapid heart rhythm. Needless to say, you should avoid vigorous or competitive sports and contact sports.

Lots of domestic appliances and devices create no interference with your ICD:

• Televisions, remote controls, tape recorders, radios, garage openers

• Kitchen appliances (toasters, blenders, electric can openers, microwave ovens, electric stoves, refrigerators)

• Washing appliances (electric washers and dryers) • Sleeping appliances (electric blankets, heating pads)

• Cosmetic appliances (hair dryers, electric shavers)

• Gardening appliances (lawn mowers, leaf blowers)

• Personal computers, printers, fax machines, electric typewriters, copying machines

• Machine shop tools (electric drills, table saws).

Certain other environments, activities, and equipment and devices can cause problems for your ICD:

• MRI (magnetic resonance imaging), radiotherapy, lithotripsy, electro surgery

• Magnetic fields (high voltage, strong electrical currents, large mechanical or industrial equipment)

• Strong magnets

• Large stereo speakers

• Battery-powered cordless power tools (screwdrivers and drills)

• Leaning over an uncovered running automobile engine

• Malfunctioning electrical or gas-powered appliances

• Being too close (closer than 6 inches) to a cellular phone. (Holding the phone to the ear opposite your implanted side is advisable.)

Your ICD identification card should be shown to airport security personnel because your ICD may set off airport security alarms. Most handheld metal detectors contain a magnet that may interfere with your ICD’s functions. Therefore, you should ask security personnel to limit scanning with such devices to less than 30 seconds over the site of the ICD or ask them to search you by hand if possible. At department store and library entrances, you may walk through most theft detection systems without harm.

What is catheter ablation, and who needs it?

Catheter ablation (or radio frequency ablation) is a nonsurgical treatment for many kinds of cardiac arrhythmias (abnormal heart rhythms) that are difficult to manage with various medications and other methods. When catheter ablation successfully corrects certain arrhythmias, the procedure is a permanent cure of a given arrhythmia.

The catheter ablation procedure will destroy parts of the abnormal electrical pathway (activity) causing a specific arrhythmia permanently. Thus, catheter ablation in many cases is effective for treating various types of rapid heart rhythms. During catheter ablation, doctors insert under mild local anesthesia a specially designed electrode catheter (a long, thin, flexible tube) into your heart via a vein in your groin or arm. Then they position the catheter in the area of the heart that’s causing a specific arrhythmia seen on an x-ray image. At the spot they determine is responsible for the arrhythmia, the electrodes at the tip of the catheter emit radiofrequency energy to destroy the small area of the heart tissue causing the arrhythmia. Catheter ablation is usually performed in conjunction with an electrophysiologic study (EPS, discussed in Question 60), and the procedure is extremely effective for certain arrhythmias when performed by well trained cardiac medical teams at well-equipped hospitals.

The procedure causes little or no discomfort and has a low risk of complications. However, since catheter ablation is an invasive procedure that requires the insertion of catheters into the heart, it does carry some small risks with some complications. You may develop bleeding at the insertion site, which could cause local swelling or bruising in the groin or arm. Some rare (but more serious) complications may include damage to your heart tissues and blood vessels, blood clot formation, and infection. If the procedure damages a normal electrical conduction system, you might need an artificial pacemaker.

For a few weeks after catheter ablation, you may experience occasional “skipped” heartbeats and palpitations. Although these symptoms are common, they are benign and self-limited events that will gradually disappear by themselves. However, you should inform your physician immediately if the rapid heart rhythm recurs or if some cardiac symptoms (chest pain, dizziness, shortness of breath, syncope or near-syncope) occur.

Like most patients, you would stay in the hospital overnight after the procedure and be able to resume your usual activities a few days after your discharge from the hospital. When catheter ablation is successful, the procedure will provide a permanent cure for many types of arrhythmias. Thus, the procedure can entirely eliminate a lifetime of many anti-arrhythmic agents (medications to treat various abnormal heart rhythms), leading to a healthy normal life.

What is cardiopulmonary resuscitation, and when is it used?

Patient comment:

Everyone should learn how to perform cardiopulmonary resuscitation (CPR), but it’s particularly important for family members who live with a heart attack victim. CPR is relatively easy to learn how to perform, and the CPR course is given by many local medical associations and hospitals.

Cardiopulmonary resuscitation (CPR) is urgently necessary when your cardiopulmonary system suddenly and unexpectedly fails to provide adequate and effective function. The purpose of CPR is to restore normal functions of the heart and lungs so that the delivery of adequate oxygen to vital organs—including the heart itself and the brain-is reestablished and maintained. Cardiac arrest most commonly occurs during the first few hours of a heart attack. Remember that permanent brain damage is a common end result when CPR is not applied within 4 minutes, even if cardiac function is restored later. In most cases, cardiac arrest and pulmonary arrest occur together, leading to cardiopulmonary arrest.

Those finding a presumed heart attack victim unconscious as a result of cardiac arrest should immediately seek emergency medical help and should apply CPR as soon as possible. A rescuer should not begin CPR until he or she has made sure that the victim is a) not breathing and b) has no heartbeat.

CPR performed on a person whose heart is beating can be harmful. The emergency line operator can give simple instructions over the phone on how to perform CPR, if no one seems to know the technique, until an ambulance arrives. As described earlier, the most common cause of cardiac arrest is ventricular fibrillation; hence, the use of an automatic external defibrillator (AED), if available, is a life-saving measure if used with performing CPR.

All medical and paramedical personnel must be fully capable of performing CPR. It is highly advisable for the general public to learn the proper technique for CPR because cardiovascular collapse is usually unpredictable. Family members of heart attack victims more urgently need a full understanding of CPR because cardiac patients have a much greater chance of developing cardiac arrest than do healthy people. The technique for CPR is relatively easy to learn, and the local Heart Association and many other medical organizations frequently give CPR courses.

Most hospitals in America commonly use the term code blue to designate cardiopulmonary arrest. A CPR team (consisting of specially trained physicians, nurses, and paramedical personnel) is on duty for immediate response to the code blue alert.

Cardiopulmonary arrest causes the loss of certain otherwise observable functions: consciousness (comatose state); pulse (no heartbeat); respiration (no breathing); heart tones (no heart sounds); and blood pressure (BP).

How CPR Is Performed

This rough guide to performing CPR should in no way take the place of CPR instruction. If you wish to be able to perform CPR, you should take a class from a certified instructor. However, the description below should provide you with a good idea of what is done in CPR and why it is done. Before you do anything else to help an apparent heart attack victim, call for help!

Your efforts may be in vain if you do not get the victim to a hospital quickly. CPR is a stop-gap measure only and is no replacement for prompt medical care. Your phone call to emergency is more likely to save the victim than any other action you take.

As stated, the purpose of the initial measure in CPR is to start and maintain the passage of air to the lungs so that adequate amounts of oxygenated blood can be delivered to all organs. Thus, the initial measure should follow the ABC guide: clearing the Airway (the route by which air travels to the lungs), starting and maintaining Breathing, and restoring blood Circulation.

As noted above, it is important to begin by making sure that the victim is incapable of breathing on his or her own, and to check for a heartbeat. In some cases, the victim may not be breathing, but still have heart activity-often ventricular fibrillation (VF), which is commonly associated with heart attacks. If VF is evident, those administering CPR should deliver a forceful blow to the sternum (around the breastbone) with the heel of the hand; they may repeat the blow once or twice more if that produces no response. A direct blow to the sternum can terminate VF and may restore normal heart rhythm. If this maneuver is not successful, however, help should immediately proceed to the next step.


The first maneuver in CPR should be to place the patient in a supine (lying down, face-up) position. The person performing CPR should place one hand behind the patient’s neck and the other hand on the forehead. When the head is tilted back, this maneuver lifts the tongue from the back of the throat so that the patient’s airway will be fully open. During this maneuver, the rescuer should remove any obvious foreign body in the mouth and airway. For many patients, this maneuver alone may be enough to restore breathing and to start recovery from cardiovascular arrest. The person providing CPR should put his or her ear over the mouth to listen for breath sounds. If the victim is breathing, no further direct action is required unless the breathing stops, but the victim should be continually monitored and transported to a hospital in an ambulance as soon as possible.


If the victim is not breathing, CPR providers should maintain the backward tilt of the patient’s head with one hand and pinch the nostrils closed with the other hand. The rescuer should place his or her mouth over the patient’s mouth, completely sealing it to avoid any leak of air (Figure 12). At the end of inspiration (breathing in), one should exhale (blow out) a longer than - usual breath into the patient’s mouth. Artificial (mouth-to-mouth) respiration should be performed at a rate of 12 breaths per minute. If the technique is correct, a rise should be noted in the patient’s chest. If the chest does not rise, the rescuer should check again for blockages in the airway, make sure the nose is pinched, and readjust the mouth position to prevent leakage. There should be no loss of air through the nose or mouth as the lungs inflates. After inflation of the lungs, one should remove the mouth from the patient’s mouth, allowing the patient’s lungs to deflate. Air should be heard escaping from the lungs during that period. A pause of about five seconds should be enough to allow the lungs to deflate before the next breath.

The principle of mouth-to-nose resuscitation is essentially the same as that of mouth-to-mouth resuscitation. In this technique, while maintaining the backward tilt with one hand, the CPR provider should close the patient’s jaw and seal the patient’s mouth with the other hand. Then, one would place the mouth over the patient’s nose and, after inhaling deeply, would exhale into the patient’s nose. Artificial respiration should be performed at a rate of 12 breaths per minute.


If the patient is not breathing and has no heartbeat (determined by feeling for a pulse in the neck or groin for about 5 seconds), the next step in the initial resuscitation measures is the application of cardiac massage. Closed-chest cardiac massage is recommended in practically all clinical circumstances except when the patient is already in the operating room or when chest wounds don’t allow closed-chest massage. To perform cardiac massage, the patient’s back must be placed on a firm surface. When the patient is on a soft surface (e.g., a bed), a hard board should be placed under the back. The reason for this is that you cannot compress the heart to pump blood adequately if the surface is soft under the victim. While standing alongside the patient, the rescuer places the heel of one hand over the lower third of the patient’s sternum; a common rule of thumb is to find the tip of the breastbone where the ribs meet and place your hand three fingers’ width up from that point. Only the heel of the hand should be in touch with the patient’s chest. The other hand may rest on the first hand.

The rescuer then compresses the patient’s chest 1.5 to 2 inches; the pressure should be smooth and uninterrupted. After that compression, the rescuer must release the sternum and ready the hand for the next compression. The duration of the chest compression should be similar to that of relaxation; that is, the amount of time spent doing the compression equals the time spent between compressions. The chest should be compressed about 60 times per minute and coordinated with artificial respiration. If only one person is present, 15 chest compressions are recommended, followed by two quick artificial respirations.

When two or more persons are available for CPR, every fifth chest compression should be followed by one lung ventilation (artificial respiration). To check the success of closed-chest cardiac massage, peripheral pulses (e.g., pulses on the neck or groin area) should be felt periodically-every minute or so-because, as stated above, if the rescuer is successful in restoring a heartbeat, the compressions should be halted. During the initial measures of CPR, one must check for several signs that indicate the success or failure of the resuscitative efforts. Important signs include pulse in the arm, groin, or neck arteries; heart tones (sounds); spontaneous breathing; and palpable or recordable BP. Of course, one should also be alert to any change in the patient’s neurologic status and in the status of consciousness.

When there is any evidence that resuscitative efforts have been successful, the rescuer may stop and observe the patient for several seconds. If the cardiovascular collapse has stopped, one should continue to observe the patient very closely. When resuscitative efforts have been successful outside a hospital setting, ambulance personnel should transport the patient promptly to a nearby ER. Needless to say, paramedic personnel of the ambulance will take over the CPR efforts as soon as they arrive at the scene. If, however, there is no change in the patient’s status, those in attendance must continue artificial respiration and cardiac massage until an ambulance arrives. They should not stop CPR for longer than 5 seconds.

After CPR

Various complications of closed-chest cardiac massage may occur, although the procedure is relatively safe in most instances. When treating children and elderly people, one must not be overly vigorous in chest compression to avoid any unnecessary damage to the ribs, sternum, and various organs. Complications of cardiac massage may include fracture of the ribs and sternum; hemothorax (bleeding in the chest cavity); hemopericarium (bleeding in the sac surrounding the heart); pneumothorax (collapse of the lungs); rupture of the stomach or the aorta (the largest arterial trunk); laceration of the liver and spleen; and bone marrow embolism (blood clots in the bone marrow).

After successful CPR, assessment of the underlying cause of the cardiopulmonary arrest is essential. Thus, the cardiac care unit (CCU) staff should closely observe and treat any patient who has recovered from cardiopulmonary arrest. First, they must manage the underlying heart disease (e.g., heart attack) together with the major complications (e.g., life-threatening arrhythmias, CHF, and the like). Some patients may require an implantable cardioverter-defibrillator (ICD), an artificial pacemaker, or various medications, depending upon the clinical circumstance.

Of course, the treatment of the underlying heart disease-heart attack-is essential. Thus, some patients may need coronary angioplasty or coronary artery bypass graft. It should be noted that after a massive heart attack, some patients may develop cardiopulmonary arrest again after recovery from their first arrest. Therefore, medical staff must monitor even more closely any heart attack victim with extensive heart muscle damage or multiple artery blockages.


Conversation with a Patient Recovered from a Heart Attack Mr. Benjamin Han is a 67-year-old retired banker (vice-president of one of the major banks) who had suffered from a heart attack 13 to 14 years ago and recovered from a heart attack without any complication. Coronary angioplasty was performed with a stent. His coronary risk factors included diabetes mellitus, abnormal blood cholesterol levels, occasional smoking, type-A personality, and some stress (job-related). His wife is a retired dentist. The following questions and answers are a candid conversation with the patient.

Q. What was the first symptom you experienced upon the onset of your heart attack?

A. On day 1, I experienced a short but severe pain in  my left chest, and the pain was sharp enough to stop my routine daily walk outside of my office. I did not take it seriously at that time, but, in retrospect, it must have been a warning sign of the oncoming heart attack the next day.

Q. Did you feel any type of chest discomfort, significant shortness of breath, tingling sensation or numbness in the arms or shoulders?

A. Soon after lunch on day 2 on the way back to my office, I felt my breathing was short, uneven, and uncomfortable. My face was pale enough for co-workers to notice. My feeling then was that I must be having a not-so-unusual indigestion problem.

Q. Did you experience marked weakness, dizziness, or feeling of a fainting spell?

A. My pale face coincided with a sense of dizziness. I do not remember actual syncope, but I remember that I was not in a talking mood, as I felt weak and uncomfortable.

Q. What were you doing when you experienced any of the above-mentioned symptoms?

A. I was waiting in front of an elevator after walking back from my lunch. My walk was not at a routine pace, however.

Q. What action did you first take when you considered that you might be having a possible heart attack?

A. As I was returning to my office, my secretary first noticed my pale face and she commented on it. As she realized my weakness and my reluctance to converse with her, her friend who happened to be visiting her remarked that I must be having a heart attack. Her friend, I found out later, was a former nurse. Her suggestion was to go to the hospital. I hesitated initially, disbelieving what I heard. However, my secretary insisted on calling my personal friend, the cardiologist Dr. Edward Chung at Thomas Jefferson University Hospital, and I finally called Dr. Chung reluctantly.

Q. How soon did you go to a nearby hospital emergency room (ER)?

A. Upon hearing my medical history over the phone,

Dr. Chung considered strongly that I was having a heart attack, and he ordered me to call an ambulance and come to his hospital ER right away.

Q. What mediations were given to you in the ER and what diagnostic tests were performed?

A. I believe that I was given a thrombolytic agent (later found out that it was tPA-tissue plasminogen activator), and a series of blood tests with an ECG was performed.

Q. What additional diagnostic tests and treatment were performed when you were transferred to the CCU?

A. Cardiac catheterization with coronary angiogram (arteriogram) before performing coronary angioplasty.

Q. Was coronary angioplasty performed? How many blood vessels (arteries) were dilated?

A. My team of doctors performed coronary angioplasty on my left anterior descending artery. I had a second angioplasty on the same coronary artery with a stent implantation 6 months later because of restenosis. At that time, the use of a stent was somewhat experimental and not yet widely used.

Q. Was coronary artery bypass graft performed? How many blood vessels were treated?

A. No bypass surgery was performed.

Q. Did you suffer from any significant complications such as congestive heart failure and abnormal heart rhythms?

A. Fortunately, I did not have any complications.

Q. Did you experience angina (chest discomfort) or any other cardiac symptoms prior to this heart attack?

A. I might have experienced a sense of sluggishness and weak muscle strength. The briefcase I carried in the morning felt burdensome. But I did not know all these feelings were related to the heart attack. I do not recall any chest discomfort (angina) in the past.

Q. How long did you stay in the hospital?

A. It must have been for about 10 days. Hospital stay at the time was not restrictive.

Q. How many medications are you taking after your discharge from the hospital?

A. Initially, I was taking aspirin and atenol everyday. Later, I added a series of vitamins C, E, and folic acid. Now, I take two baby aspirins a day, folic acid, and Zocor (cholesterol-lowering drug).

Q. Are there significant changes in your lifestyle, diet, physical exercises, and coronary risk factors?

A. My wife has been very conscientious about my diet (e.g., lean meat, balanced healthy foods) Although I preferred high cholesterol foods, I have been listening to my wife’s advice 95% of the time. I have switched my regular exercise from tennis to golf, following my doctor’s recommendation. I have an exercise routine of walking three times a week and golfing three to four times a week. I have been very deliberate in all my efforts in minimizing stress-trying not be emotionally charged, and avoiding any cause of anxiety, if at all possible.

Q. Do you have any contributing risk factors (coronary risk factors) such as smoking, family history, high blood pressure, diabetes mellitus, high cholesterol, obesity, etc.?

A. Most of my siblings seem to have a history of high cholesterol, but none seem to show high blood pressure. I am the only one in my immediate family who has diabetes, which came to me in my early 50s. I must have had a stressful career and environment. I smoked irregularly and moderately before the heart attack. Since then, I quit smoking completely.


Peripheral pulse - pulse in the arms or legs.

Hemothorax - accumulation or blood in the chest cavity.

Hemopericardium – accumulation of blood in pericardial sac.


Before you do anything else to help an apparent heart attack victim, call for help!



googleplus sm


ar bg ca zh-chs zh-cht cs da nl en et fi fr de el ht he hi hu id it ja ko lv lt no pl pt ro ru sk sl es sv th tr uk

Verse of the Day

Global Map