PCI requires cardiac catheterization, which is the insertion of a catheter tube and injection of contrast dye, usually iodine-based, into your coronary arteries. Doctors use PCI to open coronary arteries that are narrowed or blocked by the buildup of atherosclerotic plaque. PCI may be used to relieve symptoms of coronary heart disease or to reduce heart damage during or after a heart attack.

A cardiologist, or doctor who specializes in the heart, will perform PCI in a hospital cardiac catheterization laboratory. You will stay awake, but you will be given medicine to relax you. Before your procedure, you will receive medicines through an intravenous (IV) line in your arm to prevent blood clots. Your doctor will clean and numb an area on the wrist or groin where your doctor will make a small hole and insert the catheter into your blood vessel. Live x rays will help your doctor guide the catheter into your heart to inject special contrast dye that will highlight the blockage. To open a blocked artery, your doctor will insert another catheter over a guidewire and inflate a balloon at the tip of that catheter. Your doctor may put a small mesh tube called a stent in your artery to help keep the artery open.

After PCI, your doctor will remove the catheters and close and bandage the opening on your wrist or groin. You may develop a bruise and soreness where the catheters were inserted. It also is common to have discomfort or bleeding where the catheters were inserted. You will recover in a special unit of the hospital for a few hours or overnight. You will get instructions on how much activity you can do and what medicines to take. You will need a ride home because of the medicines or anesthesia you received. Your doctor will check your progress during a follow-up visit. If a stent is implanted, you will have to take special anticlotting medicines exactly as prescribed, usually for at least three to 12 months.

Serious complications from PCI don’t occur often, but they can happen. These complications may include bleeding, blood vessel damage, a treatable allergic reaction to the contrast dye, the need for emergency coronary artery bypass grafting during the procedure, arrhythmias, damaged arteries, kidney damage, heart attack, stroke, or blood clots. Sometimes chest pain can occur during PCI because the balloon briefly blocks blood supply to the heart. Restenosis, or tissue regrowth in the treated portion of the artery, may occur in the following months and cause the artery to become narrow or blocked again. The risk of complications is higher if you are older, have chronic kidney disease, are experiencing heart failure at the time of the procedure, or have extensive heart disease and multiple blockages in your coronary arteries.

The heart is an organ about the size of your fist that pumps blood through your body. It is made up of multiple layers of tissue.

Your heart is at the center of your circulatory system. This system is a network of blood vessels, such as arteries, veins, and capillaries, that carries blood to and from all areas of your body. Your blood carries the oxygen and nutrients that your organs need to work properly. Blood also carries carbon dioxide to your lungs so you can breathe it out. Inside your heart, valves keep blood flowing in the right direction.

Your heart’s electrical system controls the rate and rhythm of your heartbeat. A healthy heart supplies your body with the right amount of blood at the rate needed to work well. If disease or injury weakens your heart, your body’s organs will not receive enough blood to work normally. A problem with the electrical system—or the nervous or endocrine systems, which control your heart rate and blood pressure—can also make it harder for the heart to pump blood.

Anatomy of Your Heart

Your heart is in the center of your chest, near your lungs. It has four hollow heart chambers surrounded by muscle and other heart tissue. The chambers are separated by heart valves, which make sure that the blood keeps flowing in the right direction.

Heart Chambers

The two upper chambers of your heart are called atria, and the two lower chambers are called ventricles. Blood flows from the body and lungs to the atria and from the atria to the ventricles. The ventricles pump blood out of the heart to the lungs and other parts of the body. An internal wall of tissue divides the right and left sides of your heart. This wall is called the septum.

Heart Tissue

The heart is made of three layers of tissue.

• Endocardium, the thin inner lining of the heart chambers that also forms the surface of the valves.
• Myocardium, the thick middle layer of muscle that allows your heart chambers to contract and relax to pump blood to your body.
• Pericardium, the sac that surrounds your heart. Made of thin layers of tissue, it holds the heart in place and protects it. A small amount of fluid between the layers helps reduce friction between the beating heart and surrounding tissues.

Some conditions can affect the heart's tissue. Examples include:

• Cardiomyopathy,in which the heart muscle becomes enlarged, thick, or rigid. As cardiomyopathy worsens, the heart becomes weaker and is less able to pump blood through the body and maintain a normal electrical rhythm.
• Heart inflammation, which is inflammation in one or more of the layers of tissue in the heart, including the pericardium, myocardium, or endocardium. This can lead to serious complications, including heart failure, cardiogenic shock, or irregular heart rhythm.

Blood Flow

Arteries and veins link your heart to the rest of the circulatory system. Veins bring blood to your heart. Arteries take blood away from your heart. Your heart valves help control the direction the blood flows.

Heart valves

Heart valves control the flow of blood so that it moves in the right direction. The valves prevent blood from flowing backward.

The heart has four valves.

• The tricuspid valve separates the right atrium and right ventricle.
• The mitral valve separates the left atrium and left ventricle.
• The pulmonary valve separates the right ventricle and the pulmonary artery.
• The aortic valve separates the left ventricle and aorta.

The valves open and shut in time with the pumping action of your heart's atria and ventricles. The opening and closing involves a set of flaps called cusps or leaflets. The cusps open to allow blood to flow out of a chamber and close to allow the chamber to refill with blood. Heart valve diseases can cause backflow or slow the flow of blood through the heart.

Adding Oxygen to Blood

Oxygen-poor blood from the body enters your heart through two large veins called the superior and inferior vena cava. The blood enters the heart's right atrium and is pumped to your right ventricle, which in turn pumps the blood to your lungs.

The pulmonary artery then carries the oxygen-poor blood from your heart to the lungs. Your lungs add oxygen to your blood. The oxygen-rich blood returns to your heart through the pulmonary veins.

The oxygen-rich blood from the lungs then enters the left atrium and is pumped to the left ventricle. The left ventricle generates the high pressure needed to pump the blood to your whole body through your blood vessels.

When blood leaves the heart to go to the rest of the body, it travels through a large artery called the aorta. A balloon-like bulge, called an aortic aneurysm, can sometimes occur in the aorta.

Supplying Oxygen to the Heart's Muscle

Like other muscles in the body, your heart needs blood to get oxygen and nutrients. Yourcoronary arteries supply blood to your heart. These arteries branch off from the aorta so that oxygen-rich blood is delivered to your heart as well as the rest of your body.

• The left coronary artery delivers blood to the left side of your heart, including your left atrium and ventricle and the septum between the ventricles.
• The circumflex artery branches off from the left coronary artery to supply blood to part of the left ventricle.
• The left anterior descending artery also branches from the left coronary artery and provides blood to parts of both the right and left ventricles.
• The right coronary artery provides blood to the right atrium and parts of both ventricles.
• The marginal arteries branch from the right coronary artery and provide blood to the surface of the right atrium.
• The posterior descending artery also branches from the right coronary artery and provides blood to the bottom of both ventricles.

Some conditions can affect normal blood flow through these heart arteries. Examples include:

• Angina
• Heart attack
• Ischemic heart disease

The coronary veins return oxygen-low blood from the heart's muscles back to the right atrium so it can be pumped to the lungs. They include:

• The anterior cardiac veins.
• The great cardiac vein.
• The middle cardiac vein.
• The small cardiac vein.

Your Heart's Electrical System

Your heartbeat is the contraction of your heart to pump blood to your lungs and the rest of your body. Your heart's electrical system determines how fast your heart beats.

Your heartbeat

The contraction of the atria and ventricles makes a heartbeat. When your heart beats, it makes a “lub-DUB” sound. You may have heard this if you listened with a stethoscope or with your ear on someone's chest.

• After your atria pump blood into the ventricles, the valves between the atria and ventricles close to prevent backflow. The “lub” is the sound of these valves closing.
• After your ventricles contract to pump blood away from the heart, the aortic and pulmonary valves close and make the “DUB” sound.

Electrical activity

Electrical signals cause muscles to contract. Your heart has a special electrical system called the cardiac conduction system. This system controls the rate and rhythm of the heartbeat.

With each heartbeat, an electrical signal travels from the top of the heart to the bottom. As the signal travels, it causes the heart to contract and pump blood. The heartbeat process includes the following steps.

• The signal begins in a group of cells, called pacemaker cells, located in the sinoatrial (SA) node in the right atrium.
• The electrical signal travels through the atria, causing them to pump blood into the ventricles.
• The electrical signal then moves down to a group of pacemaker cells called the atrioventricular (AV) node, located between the atria and the ventricles. Here the signal slows down slightly, allowing the ventricles time to finish filling with blood.
• The AV node fires another signal that travels along the walls of your ventricles, causing them to contract and pump blood out of your heart.
• The ventricles relax, and the heartbeat process starts all over again in the SA node.

Your heart’s conduction system. When special cells called pacemaker cells generate electrical signals inside your heart, the heart muscle cells, called myocytes, contract as a group. Some conditions affect the heart's electrical system. Examples include:

• Arrhythmia, or an irregular heart rhythm. Atrial fibrillation is one of the most common types of arrhythmia.
• Conduction disorders, in which electrical signals either do not generate properly, or they do not travel properly through the heart, or both.

Your doctor may recommend percutaneous coronary intervention (PCI) if you have narrow or blocked coronary arteries as a result of coronary heart disease (CHD). PCI is one treatment for CHD. Other treatments include medicines and coronary artery bypass grafting (CABG). CABG is a type of surgery in which a healthy artery or vein from the body is connected, or grafted, to a blocked coronary artery.

The grafted artery or vein bypasses (that is, goes around) the blocked portion of the coronary artery. This improves blood flow to the heart.

Compared with CABG, some advantages of PCI are that it:

• Doesn't require open-heart surgery
• Doesn't require general anesthesia (that is, you won't be given medicine to make you sleep during the procedure)
• Has a shorter recovery time

However, PCI isn't for everyone. For some people, CABG might be a better option. For example, CABG might be used to treat people who have severe CHD, narrowing of the left main coronary artery, or poor function in the lower left heart chamber.

In addition, recent studies show that people with CHD who also have diabetes may have greater benefit from CABG.

Your doctor will consider many factors when deciding which treatment(s) to recommend. PCI also is used as an emergency treatment for heart attack. As plaque builds up in the coronary arteries, it can rupture. This can cause a blood clot to form on the surface of the plaque and block blood flow to the heart muscle. Quickly opening the blockage restores blood flow and reduces heart muscle damage during a heart attack.

Before you have percutaneous coronary intervention (PCI), your doctor will need to know the location and extent of the blockages in your coronary (heart) arteries. To find this information, your doctor will use coronary angiography (an-jee-OG-rah-fee). This test uses dye and special x rays to show the insides of your arteries.

During angiography, a small tube (or tubes) called a catheter is inserted into an artery, usually in the groin (upper thigh). The catheter is threaded to the coronary arteries.

Special dye, which is visible on x-ray pictures, is injected through the catheter. The x-ray pictures are taken as the dye flows through your coronary arteries. The dye shows whether blockages are present and their location and severity.

During PCI, another catheter with a balloon at its tip (a balloon catheter) is inserted in the coronary artery and placed in the blockage. Then, the balloon is expanded. This pushes the plaque against the artery wall, relieving the blockage and improving blood flow.

Stent

A small mesh tube called a stent usually is placed in the artery during the procedure. The stent is wrapped around the deflated balloon catheter before the catheter is inserted into the artery.

When the balloon is inflated to compress the plaque, the stent expands and attaches to the artery wall. The stent supports the inner artery wall and reduces the chance of the artery becoming narrow or blocked again.

Some stents are coated with medicine that is slowly and continuously released into the artery. They are called drug-eluting stents. The medicine helps prevent scar tissue from blocking the artery following PCI.

Percutaneous coronary intervention (PCI) is done in a hospital. A cardiologist will perform the procedure. A cardiologist is a doctor who specializes in diagnosing and treating heart diseases and conditions.

If PCI isn't done as an emergency treatment, you'll meet with your cardiologist beforehand. He or she will go over your medical history (including the medicines you take), do a physical exam, and talk to you about the procedure.

Your doctor also may recommend tests, such as blood tests, an EKG (electrocardiogram), and a chest x ray.

Once the procedure is scheduled, your doctor will advise you:

• When to begin fasting (not eating or drinking) before the procedure. Often, you have to stop eating and drinking 6–8 hours before the procedure.
• What medicines you should and shouldn't take on the day of the procedure.
• When to arrive at the hospital and where to go.

Even though PCI takes only 1–2 hours, you'll likely need to stay in the hospital overnight. Your doctor may advise you to not drive for a certain amount of time after the procedure. Thus, you'll probably need to arrange a ride home.

Percutaneous coronary intervention (PCI) is done in a special part of the hospital called the cardiac catheterization (KATH-eh-ter-ih-ZA-shun) laboratory. The "cath lab" has special video screens and x-ray machines.

Your doctor will use this equipment to see enlarged pictures of the blockages in your coronary arteries.

Preparation

In the cath lab, you'll lie down. An intravenous (IV) line will be placed in your arm to give you fluids and medicines. The medicines will relax you and help prevent blood clots from forming.

The area where your doctor will insert the catheter will be shaved. The catheter usually is inserted in your groin (upper thigh). The shaved area will be cleaned and then numbed. The numbing medicine may sting as it's going in.

The Procedure

During the PCI, you'll be awake but sleepy. Your doctor will use a needle to make a small hole in an artery in your arm or groin. A thin, flexible guide wire will be inserted into the artery through the small hole. Then, your doctor will remove the needle and place a tapered tube called a sheath over the guide wire and into the artery.

Next, your doctor will put a long, thin, flexible tube called a guiding catheter through the sheath and slide it over the guide wire. The catheter is moved to the opening of a coronary artery, and the guide wire is removed. Your doctor will inject special dye through the catheter. The dye will help show the inside of the coronary artery and any blockages on an x-ray picture called an angiogram. Another guide wire is then put through the catheter into the coronary artery and threaded past the blockage. A thin catheter with a balloon at its tip (a balloon catheter) is threaded over the wire and through the guiding catheter.

The balloon catheter is positioned in the blockage. Then, the balloon is inflated. This pushes the plaque against the artery wall, relieving the blockage and improving blood flow through the artery. Sometimes the balloon is inflated and deflated more than once to widen the artery.

Your doctor may put a stent (small mesh tube) in your artery to help keep it open. If so, the stent will be wrapped around the balloon catheter.

When your doctor inflates the balloon, the stent will expand against the wall of the artery. When the balloon is deflated and pulled out of the artery with the catheter, the stent remains in place in the artery.

After the PCI is done, the sheath, guide wires, and catheters are removed from your artery. Pressure is applied to stop bleeding at the catheter insertion site. Sometimes a special device is used to seal the hole in the artery.

During the PCI, you'll receive strong antiplatelet medicines through your IV line. These medicines help prevent blood clots from forming in the artery or on the stent. Your doctor may start you on antiplatelet medicines before the procedure.

After percutaneous coronary intervention (PCI), you'll be moved to a special care unit. You'll stay there for a few hours or overnight. You must lie still for a few hours to allow the blood vessel in your arm or groin (upper thigh) to seal completely.

While you recover, someone on your health care team will check your blood pressure, heart rate, oxygen level, and temperature. The site where the catheters were inserted also will be checked for bleeding. That area may feel sore or tender for a while.

Going Home

Most people go home the day after the procedure. When your doctor thinks you're ready to leave the hospital, you'll get instructions to follow at home, such as:

• How much activity or exercise you can do. (Most people are able to walk the day after the PCI procedure.)
• When you should follow up with your doctor.
• What medicines you should take.
• What you should look for daily when checking for signs of infection around the catheter insertion site. Signs of infection include redness, swelling, and drainage.
• When you should call your doctor. For example, you may need to call if you have shortness of breath; a fever; or signs of infection, pain, or bleeding.
• When you should call 9–1–1 (for example, if you have any chest pain).

Your doctor will prescribe medicine to help prevent blood clots from forming. Take all of your medicine as your doctor prescribes.

If you got a stent during the PCI, the medicine reduces the risk that blood clots will form in the stent. Blood clots in the stent can block blood flow and cause a heart attack.

Recovery and Recuperation

Most people recover from the PCI and return to work within a week of leaving the hospital.

Your doctor will want to check your progress after you leave the hospital. During the follow-up visit, your doctor will examine you, make changes to your medicines (if needed), do any necessary tests, and check your overall recovery.

Use this time to ask questions you may have about activities, medicines, or lifestyle changes, or to talk about any other issues that concern you.

Lifestyle Changes

Although PCI can reduce the symptoms of coronary heart disease (CHD), it isn't a cure for CHD or the risk factors that led to it. Making healthy lifestyle changes can help treat CHD and maintain the good results from PCI.

Talk with your doctor about your risk factors for CHD and the lifestyle changes you should make. Lifestyle changes might include changing your diet, quitting smoking, being physically active, losing weight or maintaining a healthy weight, and reducing stress.

Cardiac Rehabilitation

Your doctor may recommend cardiac rehabilitation (rehab). Cardiac rehab is a medically supervised program that helps improve the health and well-being of people who have heart problems.

Cardiac rehab includes exercise training, education on heart healthy living, and counseling to reduce stress and help you return to an active life. Your doctor can tell you where to find a cardiac rehab program near your home.

Percutaneous coronary intervention (PCI) is a common medical procedure. Serious complications don't occur often. However, they can happen no matter how careful your doctor is or how well he or she does the procedure.

PCI complications can include:

• Discomfort and bleeding at the catheter insertion site.
• Blood vessel damage from the catheters.
• An allergic reaction to the dye used during the procedure.
• An arrhythmia (irregular heartbeat).
• The need for emergency coronary artery bypass grafting during the procedure (less than 3 percent of people). This may occur if an artery closes down instead of opening up.
• Kidney damage caused by the dye used during the procedure.
• Heart attack (3–5 percent of people).
• Stroke (less than 1 percent of people).

Sometimes chest pain can occur during PCI because the balloon briefly blocks blood supply to the heart.

As with any procedure involving the heart, complications can sometimes be fatal. However, this is rare with PCI. Less than 2 percent of people die during the procedure.

The risk of complications is higher in:

• People aged 65 and older
• People who have chronic kidney disease
• People who are in shock
• People who have extensive heart disease and blockages in their coronary (heart) arteries

Research on PCI is ongoing to make it safer and more effective and to prevent treated arteries from narrowing again.

Restenosis

Another problem that can occur after PCI is too much tissue growth within the treated portion of the artery. This can cause the artery to become narrow or blocked again, often within 6 months. This complication is called restenosis (RE-sten-o-sis).

When a stent (small mesh tube) isn't used during PCI, 30 percent of people have restenosis. When a stent is used, 15 percent of people have restenosis.

Stent Restenosis

Stents coated with medicine (drug-eluting stents) reduce the growth of scar tissue around the stent. These stents further reduce the risk of restenosis. When these stents are used, about 10 percent of people have restenosis.

Other treatments, such as radiation, can help prevent tissue growth within a stent. For this procedure, a wire is put through a catheter to where the stent is placed. The wire releases radiation to stop any tissue growth that may block the artery.

Blood Clots

Studies suggest that there's a higher risk of blood clots forming in medicine-coated stents compared with bare metal stents. However, no firm evidence shows that these stents increase the chance of having a heart attack or dying if used as recommended. Researchers continue to study medicine-coated stents.

Taking medicine as prescribed by your doctor can lower your risk of blood clots. People who have medicine-coated stents usually are advised to take antiplatelet medicines, such as clopidogrel and aspirin, for up to a year or longer.

As with all procedures, you should talk with your doctor about your treatment options, including the risks and benefits.