• Collateral Circulation


 
• As the size of the blockage in a coronary artery increases, the narrowed coronary artery may develop “collateral circulation.” Collateral circulation is the development of new blood vessels that reroute blood flow around the blockage. However, during times of increased exertion or stress, the new arteries may not be able to supply enough oxygen-rich blood to the heart muscle.

• What is ischemia?

• Ischemia is a condition described as “cramping of the heart muscle.” Ischemia occurs when the narrowed coronary artery reaches a point where it cannot supply enough oxygen-rich blood to meet the heart’s needs. The heart muscle becomes “starved” for oxygen.

• Ischemia of the heart can be compared to a cramp in the leg. When someone exercises for a very long time, the muscles in the legs cramp up because they’re starved for oxygen and nutrients. Your heart, also a muscle, needs oxygen and nutrients to keep working. If the heart muscle’s blood supply is inadequate to meet its needs, ischemia occurs, and you may feel chest pain or other symptoms.

• Ischemia is most likely to occur when the heart demands extra oxygen. This is most common during exertion (activity), eating, excitement or stress, or exposure to cold.

• When ischemia is relieved in less than 10 minutes with rest or medications, you may be told you have “stable coronary artery disease” or “stable angina.” Coronary artery disease can progress to a point where ischemia occurs even at rest.

• Ischemia, and even a heart attack, can occur without any warning signs and is called “silent” ischemia. Silent ischemia can occur among all people with heart disease, though it is more common among people with diabetes.

• What are the symptoms of coronary artery disease? 


 
The most common symptom of coronary artery disease is angina (also called angina pectoris). Angina is often referred to as chest pain. It is also described as chest discomfort, heaviness, tightness, pressure, aching, burning, numbness, fullness, or squeezing. It can be mistaken for indigestion or heartburn. Angina is usually felt in the chest, but may also be felt in the left shoulder, arms, neck, back or jaw.

Other symptoms that can occur with coronary artery disease include:

• Shortness of breath
• Palpitations (irregular heartbeats, skipped beats or a “flip-flop” feeling in your chest)
• A faster heartbeat
• Dizziness
• Nausea
• Extreme weakness
• Sweating
If you experience any of these symptoms, it is important to call your doctor, especially if these are new symptoms or if they have become more frequent or severe.

What you should do if you have symptoms:

• If you or someone you are with has chest, left arm or back pain that lasts more than 5 minutes, with one or more of the symptoms listed previously,  get emergency help. DO NOT DELAY. Quick treatment of a heart attack is very important to reduce the amount of damage to your heart. Emergency personnel may tell you to chew an aspirin to break up a possible blood clot, if there is no medical reason for you not to take aspirin.

• If your symptoms stop completely in 5 minutes, still call your doctor to report your symptoms.

• Call your doctor if this is the first time you have experienced these symptoms so you can be evaluated.

• Learn to recognize your symptoms and the situations that cause them.

• Call your doctor if you have new symptoms or if they become more frequent or severe.

• If you have been prescribed nitroglycerin and you experience angina, stop what you are doing and rest. Take one nitroglycerin tablet and let it dissolve under your tongue, or if using the spray form, spray it under your tongue. Wait 5 minutes. If you still have angina after 5 minutes, get emergency help. DO NOT DELAY.

• How is coronary artery disease diagnosed?

• Your doctor diagnoses coronary artery disease by talking to you about your symptoms, medical history and risk factors, and performing a physical exam.

• Diagnostic tests, including blood tests, an electrocardiogram (ECG or EKG), exercise stress tests, cardiac catheterization and others. These tests help your doctor evaluate the extent of your coronary heart disease, its effect on the function of your heart, and the best form of treatment for you.

• Research into new testing procedures, such as coronary computed tomography angiogram (CTA), may change the way coronary artery disease is diagnosed in the future.

• Tests used to predict increased risk for coronary artery disease include: C-reactive protein (CRP), complete lipid profile and calcium score screening heart scan.

• What is cardiac catheterization ?

Cardiac catheterization (also called cardiac cath or coronary angiogram) is an invasive imaging procedure that allows your doctor to evaluate your heart function. Cardiac catheterization is used to:

• Evaluate or confirm the presence of coronary artery disease, valve disease or disease of the aorta

• Evaluate heart muscle function

• Determine the need for further treatment (such as an interventional procedure or coronary artery bypass graft, or CABG, surgery)

During a cardiac catheterization, a long, narrow tube called a catheter is inserted through a plastic introducer sheath (a short, hollow tube that is inserted into a blood vessel in your arm or leg). The catheter is guided through the blood vessel to the coronary arteries with the aid of a special x-ray machine.

Contrast material is injected through the catheter and x-ray movies are created as the contrast material moves through the heart’s chambers, valves and major vessels. This part of the procedure is called a coronary angiogram (or coronary angiography). The digital photographs of the contrast material are used to identify the site of the narrowing or blockage in the coronary artery.




• What are the risk factors for coronary artery disease?

Non-modifiable risk factors (those that cannot be changed) include:

• Being male. The risk of heart attack is greater in men than in women, and men have heart attacks earlier in life than women. However, at age 70 and beyond, men and women are equally at risk.

• Older age. Coronary artery disease is more likely to occur as you get older, especially after age 65.

• Family history of heart disease. If your parents have heart disease (especially if they were diagnosed with heart disease before age 50), you have an increased risk of developing it. Ask your doctor when it’s appropriate for you to start screenings for heart disease so it can be detected and treated early.         

Modifiable risk factors (those you can treat or control) include:

• Cigarette smoking and exposure to tobacco smoke

• High blood cholesterol and high triglycerides -- especially high LDL or “bad” cholesterol over 100 mg/dL and low HDL or “good” cholesterol under 40 mg/dL. Some patients who have existing heart or blood vessel disease and other patients who have a very high risk should aim for a LDL level less than 70 mg/dL. Your doctor can provide specific guidelines.

• High blood pressure (140/90 mm/Hg or higher)

• Uncontrolled diabetes

• Physical inactivity

• Being overweight (body mass index or BMI from 25-29 kg/m 2 ) or being obese (BMI higher than 30 kg/m 2 )

• Note: How your weight is distributed is important. Your waist measurement is one way to determine fat distribution. Your waist circumference is the measurement of your waist, just above your navel. The risk of cardiovascular disease increases with a waist measurement of over 35 inches in women and over 40 inches in men.

• Uncontrolled stress or anger

• Diet high in saturated fat and cholesterol

• Drinking too much alcohol

The more risk factors you have, the greater your risk of developing coronary artery disease.

• How is coronary artery disease treated?

Treatment for coronary artery disease involves reducing your risk factors, taking medications as prescribed, possibly undergoing invasive and/or surgical procedures and seeing your doctor for regular visits. Treating coronary artery disease is important to reduce your risk of a heart attack or stroke.
Reduce your risk factors 

Reducing your risk factors involves making lifestyle changes. Your doctor will work with you to help you make these changes.

•If you smoke, you should quit.

•Make changes in your diet to reduce your cholesterol, control your blood pressure, and manage blood sugar if you have diabetes. Low-fat, low-sodium and low-cholesterol foods are recommended. Limiting alcohol to no more than one drink a day is also important. A registered dietitian can help you make the right dietary changes. The Cleveland Clinic offers nutrition programs and classes to help you reach your goals.

•Increase your exercise/activity level to help achieve and maintain a healthy weight and reduce stress. But, check with your doctor before starting an exercise program. Ask your doctor about participating in a cardiac rehabilitation program.

Take medications as prescribed.

If lifestyle changes aren’t enough to control your heart disease, medications may be prescribed to treat certain risk factors, such as high cholesterol or high blood pressure, to help your heart work more efficiently and receive more oxygen-rich blood. The medications you will be prescribed will depend on your personal needs, presence of other health conditions and your specific heart problem.

Have procedures to treat coronary artery disease, as recommended


 
Interventional procedures

Common interventional procedures to treat coronary artery disease include balloon angioplasty (PTCA) and stent or drug-eluting stent placement. These procedures are considered non-surgical because they are done by a cardiologist through a tube or catheter inserted into a blood vessel, rather than by a surgeon through an incision. Several types of balloons and/or catheters are available to treat the plaque within the vessel wall. The physician chooses the type of procedure based on individual patient needs.

Coronary artery bypass graft (CABG) surgery

One or more blocked coronary arteries are bypassed by a blood vessel graft to restore normal blood flow to the heart. These grafts usually come from the patient’s own arteries and veins located in the chest, arm or leg. The graft goes around the clogged artery (or arteries) to create new pathways for oxygen-rich blood to flow to the heart.

• What is coronary artery bypass surgery?

• CABG is a heart surgery procedure in which one or more blocked coronary arteries are bypassed by a blood vessel graft to restore normal blood flow to the heart. These grafts usually come from the patient’s own arteries and veins located in the chest (thoracic), leg (saphenous) or arm (radial). The graft goes around the blocked artery (or arteries) to create new pathways for oxygen-rich blood to flow to the heart.

• The goals of the procedure are to relieve symptoms of coronary artery disease (including angina), enable the patient to resume a normal lifestyle and to lower the risk of a heart attack or other heart problems.

• Who is eligible for coronary artery bypass surgery?

• The decision to prescribe medical treatment, invasive procedures or cardiac bypass surgery depends on several factors including the extent of cardiovascular disease, the severity of symptoms, your age and other medical conditions. The cardiologist (heart specialist) and surgeon will determine the best method of therapy for each patient.

What happens during coronary bypass surgery?


 
• The surgery generally lasts from three to five hours, depending on the number of arteries being bypassed. After general anesthesia is administered, the surgeon removes the veins or prepares the arteries for grafting.

• There are several types of bypass grafts that can be be used in cardiac bypass surgery. The surgeon decides which graft(s) to use, depending on the location of the blockage, the amount of the blockage and the size of the patient’s coronary arteries.


                                                      
• Internal mammary arteries [also called IMA grafts or internal thoracic arteries (ITA)] are the most common bypass grafts used, as they have shown the best long-term results. In most cases, these arteries can be kept intact at their origin because they have their own oxygen-rich blood supply, and then sewn to the coronary artery below the site of the blockage. If the surgeon removes the mammary artery from its origin, it is called a “free” mammary artery. Over the last decade, more than 90% of all patients received at least one internal artery graft.


                                    
• The radial (arm) artery is another common type of arterial graft. There are two arteries in the arm, the ulnar and radial arteries. Most people receive blood to their arm from the ulnar artery and will not have any side effects if the radial artery is used. Careful preoperative and intraoperative tests determine if the radial artery can be used. If the radial artery is used as the graft, the patient may be required to take a calcium channel blocker medication for several months after surgery. This medication helps keep the artery open. Some people report numbness in the wrist after surgery. However, long-term sensory loss or numbness is uncommon.

• Saphenous veins harvested from leg and thighs can be used as bypass grafts

Surgical Procedure

To bypass the blockage, the surgeon makes a small opening just below the blockage in the diseased coronary artery. If a saphenous (leg) or radial (arm) vein is used, one end is connected to the coronary artery and the other to the aorta. If a mammary artery is used, one end is connected to the coronary artery while the other remains attached to the aorta. The graft is sewn into the opening, redirecting the blood flow around this blockage.

The procedure is repeated until all affected coronary arteries are treated. It is common for three or four coronary arteries to be bypassed during surgery.
Before the patient leaves the hospital, the doctor or nurse will explain the specific bypass procedure that was performed.

Heart-Lung Machine 

During surgery, the heart-lung bypass machine (called “on-pump” surgery) is used to take over for the heart and lungs, allowing the circulation of blood throughout the rest of the body. The heart’s beating is stopped so the surgeon can perform the bypass procedure on a “still” heart.

                         
• What is “off-pump (beating heart)  coronary bypass surgery?


                      
Watch off-pump CABG video

A desire to improve outcomes after surgery and advances in technology have led surgeons to perform coronary artery bypass surgery without cardiopulmonary bypass, called off-pump bypass (also called "beating heart") surgery.

Traditionally, coronary artery bypass surgery is performed with the assistance of cardiopulmonary bypass. The heart-lung machine allows the heart’s beating to be stopped, so that the surgeon can operate on a surface which is blood-free and still. The heart-lung machine maintains life despite the lack of a heartbeat, removing carbon dioxide from the blood and replacing it with oxygen before pumping it around the body. The heart-lung machine has saved countless lives.

Off-pump coronary artery bypass surgery differs from traditional coronary artery bypass surgery, because the heart-lung machine is not used. Rather than stopping the heart, technological advances and new kinds of operating equipment now allow the surgeon to hold stabilize portions of the heart during surgery. With a particular area of the heart stabilized, the surgeon can go ahead and bypass the blocked artery in a highly controlled operative environment. Meanwhile, the rest of the heart keeps pumping and circulating blood to the body.

Off-pump coronary artery bypass surgery may be performed in certain patients with coronary artery disease. With present technology, all arteries on the heart can be bypassed off-pump. It may be ideal for certain patients who are at increased risk for complications from cardiopulmonary bypass, such as those who have heavy aortic calcification, carotid artery stenosis, prior stroke, or compromised pulmonary or renal function. Not all patients are a candidate. The selection of patients who undergo off-pump surgery is made at the time of surgery when the patient's heart and arteries are evaluated more closely.

• Recovery and instructions after coronary artery bypass surgery

Full recovery from coronary artery bypass graft surgery takes around two months. Most patients are able to drive in about three to eight weeks after surgery. Your doctor will provide specific guidelines for your recovery and return to work, including specific instructions on activity and how to care for your incision and general health after the surgery.

Coronary artery bypass graft surgery does not prevent coronary artery disease from recurring, therefore lifestyle changes and prescribed medications are strongly recommended to reduce this risk.

Lifestyle changes include:

• Quitting smoking
• Treating high cholesterol
• Managing high blood pressure and diabetes
• Exercising regularly
• Maintaining a healthy weight
• Eating a heart-healthy diet
• Controlling stress and anger
• Taking prescribed medications as ordered
• Participating in a cardiac rehabilitation program, as recommended
• Following up with your doctor for regular visits

• What is an cardiac interventional procedure ?

• An interventional procedure is a non-surgical treatment used to open narrowed coronary arteries to improve blood flow to the heart. An interventional procedure can be performed during a diagnostic cardiac catheterization when a blockage is identified, or it may be scheduled after a catheterization has confirmed the presence of coronary artery disease.

• An interventional procedure starts out the same way as a cardiac catheterization. Once the catheter is in place, one of these interventional procedures is performed to open the artery: balloon angioplasty, stent placement, rotablation or cutting balloon.

Balloon angioplasty:

• A procedure in which a small balloon at the tip of the catheter is inserted near the blocked or narrowed area of the coronary artery. The technical name for balloon angioplasty is percutaneous transluminal coronary angioplasty (PTCA) or percutaneous coronary intervention (PCI). When the balloon is inflated, the fatty plaque or blockage is compressed against the artery walls and the diameter of the blood vessel is widened (dilated) to increase blood flow to the heart.

Balloon angioplasty with stenting:

• In most cases, balloon angioplasty is performed in combination with the stenting procedure. A stent is a small, metal mesh tube that acts as a scaffold to provide support inside the coronary artery. A balloon catheter, placed over a guide wire, is used to insert the stent into the narrowed artery. Once in place, the balloon is inflated and the stent expands to the size of the artery and holds it open. The balloon is deflated and removed, and the stent stays in place permanently. During a period of several weeks, the artery heals around the stent.

• Angioplasty with stenting is most commonly recommended for patients who have a blockage in one or two coronary arteries. If there are blockages in more than two coronary arteries, coronary artery bypass graft surgery may be recommended.
Drug-eluting stents (DES):

• Drug-eluting stents contain a medication that is actively released at the stent implantation site. Drug-eluting stents have a thin surface of medication to reduce the risk of restenosis.

• If you receive a drug-eluting stent, your doctor will prescribe certain medications for several months after your procedure to prevent the risk of clotting in the stent. It is extremely important to keep taking the medications as prescribed until your doctor tells you otherwise.

• If you have concerns about drug-eluting stents, please talk with your physician.

• What is heart valve surgery ?

Heart valve surgery is a procedure used to repair or replace diseased heart valves. Over the past few years, there have been great advances in the surgical treatment of diseased heart valves by heart valve surgery. The diagnostic tests your heart doctor orders help to identify the location, type and extent of your valve disease. The results of these tests, the structure of your heart, your age, and your lifestyle will help your cardiologist, surgeon, and YOU decide what type of heart valve surgery procedure will be best for you.

Valve disease can be treated by protecting your valve from further damage, taking medications, seeing your doctor for regular visits and having heart valve surgery.
During  heart valve surgery, a surgeon will make an incision down the center of your sternum (breastbone) to get direct access to your heart. The surgeon then repairs or replaces your abnormal heart valve or valves.

                        
There are two types of heart valve surgery: valve repair surgery and valve replacement surgery.

Heart valve repair surgery 

The mitral valve is the most commonly repaired valve, but the aortic and tricuspid valves may also undergo some of these repair techniques.

Common valve repairs

Commissurotomy

Fused valve leaflets are separated to widen the valve opening

Before commisurotomy

After commisurutomy

Triangular Resection Mitral Valve Repair

If a portion of the mitral valve leaflet is flail (floppy), and bows back into the left atrium, a segment may be cut out and the leaflet sewn back together, allowing the valve to close more tightly. If the valve annulus is too wide, it may be reshaped or tightened by sewing a ring around the annulus (annuloplasty).
 
Heart valve replacement surgery

If valve repair is not an option, your surgeon may choose to replace the valve. The native valve is removed and a new valve is sewn to the annulus of your native valve. When a patient requires a heart valve replacement, two types are available – a mechanical heart valve or a valve made of animal or human tissue.

Mechanical valve replacement


 
Mechanical valves are manufactured from a biocompatible metal, plastic or ceramic-like material. The valve itself consists of a ring, with one or two moveable discs inside that open and close to control the flow of blood, much like a natural heart valve.

What are the advantages of mechanical valves? What are the disadvantages?

Mechanical valves perform well and are very durable. They usually last throughout the patient’s lifetime and do not require replacement.

On the other hand, because mechanical valves are made from metal or plastic, patients are required to take anticoagulation medication (blood thinners) throughout their lifetime to prevent the formation of blood clots. These clots could result in strokes or other serious medical problems.

Anticoagulation therapy also becomes a lifestyle issue for many patients. They must be regularly tested to ensure that the proper dosage is being administered – if it is too high, bleeding complications can result, especially bleeding into joints or internal organs. If the level is too low, the risk of stroke increases. In addition, patients must remember to take anticoagulants daily.

And because of the need for anticoagulant therapy, many patients who receive mechanical valves must maintain a special diet and refrain from physical activities that could result in injury.

Tissue valves (also called biologic or bioprosthetic valves):


 
What are tissue valves? How do they work?

Tissue valves are made of porcine (pig), bovine (cow) or human tissue and more closely resemble the body’s natural valves.

Tissue valves can either be “stented” or “stentless.” Much like the heart’s natural valves, tissue valves contain leaflets that control the flow of blood. A stented valve includes a frame on which the valve is mounted to provide support for the leaflets. A stentless valve is most often an actual heart valve obtained from either a human donor (homograft) or a pig (bioprosthesis) – this type of valve incorporates the “natural” leaflets found in an original heart valve.

What are the advantages of tissue valves? What are the disadvantages?

Because of their origins, tissue valves more closely mimic natural valves than mechanical valves do. As such, tissue valves typically do not require the prolonged use of anticoagulation medication and therefore may provide a better quality of life.

One key disadvantage is that because tissue valves so closely mimic the heart’s natural valves, they are also prone to the same “wearing out” and calcification that we see as heart valve disease develops. This calcification can build up on a tissue valve and result in stiffened leaflets and impaired valve function.

What is the preferred replacement valve option among physicians? Patients?

Each replacement valve is preferred for different attributes. Mechanical valves have long been the first choice for those patients that are expected to live for several years beyond the replacement of their valve, given the mechanical valve’s established track record for durability.

Historically, tissue valves have been selected primarily for more elderly patients, given that until recently, data did not exist supporting the long-term durability and functionality of these valves.

In the last five to ten years, physicians and patients are increasingly selecting tissue valves for a number of reasons:

 The worldwide population is aging, thus enlarging the pool of patients that have historically been ideal candidates for tissue valves.

 Data in support of the long-term performance and durability of tissue valves has been established and is beginning to be presented and published.

 Patients are increasingly looking for treatment options that enhance their lives, not limit it. Many see a lifelong commitment to anticoagulation therapy and monitoring as limiting.

• What are the surgical options in heart failure ?

• Coronary artery bypass surgery
• Valve surgery
• Left ventricular restoration  surgery
• Heart transplant

Coronary artery bypass graft (CABG) surgery

If a coronary artery becomes blocked or there are many coronary arteries that have plaque buildup leading to less-than-normal blood flowing through them, less oxygen-rich blood reaches the heart muscle. The heart muscle becomes starved for oxygen and is unable to pump normally, leading to heart failure.

During coronary artery bypass graft surgery, one or more blocked coronary arteries are bypassed by a blood vessel graft to restore normal blood flow to the heart muscle.

These grafts usually come from the patient's own arteries and veins located in the chest, leg, or arm. The graft goes around the clogged or semi-clogged artery (or arteries) to create new pathways for oxygen-rich blood to flow to the heart muscle.

Your doctor will determine if your heart failure is caused by coronary artery disease and if you have blockages that can be bypassed. Although patients with heart failure have an increased surgical risk during CABG, new strategies before, during and after surgery have decreased the risks and have improved outcomes.

Valve surgery

As heart failure progresses, changes in the left ventricle cause the papillary muscles (which support the mitral valve leaflets) to stretch out of shape, causing the valve to leak. Mitral valve repair usually involves reshaping the leaflets and providing support to the mitral valve with a ring. Mitral valve repair surgery preserves the natural anatomy of the heart, improves cardiac function, decreases heart failure symptoms and complications. 

Heart failure can occur from aortic valve stenosis (or blockage). If the valve cannot open fully, less blood is pumped from the left lower chamber of the heart (left ventricle) to the body, leading to less oxygen-rich blood to the organs and muscles.

Aortic valve replacement surgery improves exercise tolerance and quality of life for patients with heart failure.

Left ventricular restoration surgery

When a heart attack occurs in the left ventricle (left lower pumping chamber of the heart), a scar forms. The scarred area can become thin and bulge out with each beat. The bulging thin area is called an aneurysm. These changes, along with other heart muscle damage you have, may result in heart failure. Initially your heart will pump harder, but over time, the left ventricle becomes larger than normal and pumps less effectively. In left ventricular reconstruction surgery, the surgeon removes the scarred heart muscle and/or the aneurysm tissue to return the left ventricle to a more normal shape. In some cases, a patch is placed in the area that was previously scar tissue.
The goal is to improve the function of your heart. Symptoms of heart failure or chest pain will be improved, as will quality of life.

Heart transplantation

Despite medical and surgical advances in the treatment of chronic heart failure, many patients will continue to progress to advanced, end-stage failure.

Heart transplantation is recommended only when absolutely necessary and when all other treatment options have been tried or considered. Heart transplant is performed when there are no other existing conditions that would prevent a successful surgery and recovery, and when transplant is likely to be associated with long-term success.