Open Heart Surgery

Coronary Bypass Surgery

Coronary Artery Bypass Grafting (CABG)

What is Coronary Artery Bypass Grafting?
Coronary artery bypass grafting, or bypass surgery is a surgical procedure performed to relieve angina and increase the circulation and nourishment to the heart muscle. This often reduces the risk of death from coronary artery disease. Arteries and or veins from elsewhere in the patient's body are used as a passageway from the aorta to the coronary arteries to bypass atherosclerotic narrowings and improve the blood supply to the coronary circulation supplying the heart muscle.

Coronary artery bypass surgery is a very common operation. It is considered major surgery and is performed routinely every day. It is estimated that 350,000 bypass surgeries are performed annually in the United States, making it one of the most commonly performed major operations. CABG is advised for selected groups of patients with significant narrowings and blockages of the heart arteries (coronary artery disease).

What are the indications for CABG?
In order to understand the indications one must understand the anatomy. Specifically, there are three major blood vessels that comprise the coronary arteries.

• Left anterior descending
• Circumflex artery
• Right coronary artery

The left and right coronary arteries originate at the base of the aorta. These vessels exist on the surface of the heart and branch into smaller arteries that dive into the myocardium and become the microvascular resistance vessels that regulate coronary blood flow. Usually surgery is indicated on patients that have a significant number of narrowings of the major coronary arteries.

There are absolute indications for CABG meaning most clinicians agree on them and relative indications meaning there are certain circumstances that indicate surgery. The absolute indications are for three groups of patients that have significant benefit from CABG.

• Those with triple vessel disease with reduced heart function
• Those with left main disease
• Those with diabetes mellitus

The relative indications CABG are when an individual patient is experiencing severe angina that cannot be controlled with medicines alone.

The most important thing to keep in mind is that coronary artery disease is complex and every patient's specific situation is different. You should therefore discuss your circumstances with your doctor.

What to expect if you undergo CABG

Preoperative Issues
There are three separate preoperative groups: elective, urgent and emergent groups

• Elective:
  The need for surgery is not immediate after the diagnosis. Some patients that have stable angina are in this category, as well as patients with valvular heart disease. Patients are admitted directly from home.
• Urgent:
  Surgery is advisable soon after the diagnosis of coronary artery disease. Urgent surgical patients are those that have had a recent heart attack and those patients with left main coronary disease or an unstable angina pattern. These patients usually remain in the hospital following their diagnostic procedure.
• Emergent:
  Emergent operations are usually done as the same day of the diagnostic procedure. Surgery will be performed because of a life threatening condition. Often the time to discuss the operation is limited given the gravity of the situation

In each of these cases there is a team of people that will look out for your welfare. There are many systems in place to assure your safety throughout the hospital and within our practice. You can expect that your surgeon will explain the operative procedure prior to the operation. This discussion will include the risk, benefits and alternatives to each procedure.

Intraoperative Issues
The first event that will happen is that a nurse will greet you and determine your identity and ask what operation you are having. This may seem redundant, but it is designed as a patient safety measure. The anesthesiologist will then place several special lines that will be in place for monitoring your blood pressure and various parameters to keep you healthy and safe.

Once you are asleep, your doctor will retrieve a healthy vein or artery from your leg (saphenous vein), forearm (radial artery), or chest area (internal mammary artery). Removing these vessels does not deprive the leg or forearm of adequate blood flow. The vein chosen depends on your anatomy. Ask your doctor if you have any questions. In the most common type of bypass operation, an incision is made over the breastbone, or sternum (called sternotomy). Your surgeon will choose one of two methods for performing the bypass surgery.

• The first method involves the standard use of the heart and lung machine. The heart and lung machine effectively takes over the function of your heart and lung. This method remains the gold standard to which all other results should be measured.
• The second method is the “off pump” method in which coronary artery bypass grafting is performed without the heart lung machine. The heart remains beating throughout the surgical procedure.

Postoperative Issues
After the procedure, you will probably spend four to seven days in the hospital. You will be watched closely in an intensive care unit for the first few hours and your heart will be monitored continuously. It is not abnormal to spend a day or two in the ICU. You may have a breathing tube to help you temporarily, and there will probably be two to three draining tubes inserted in your chest. These will be removed a couple of days after surgery. Slowly all of the tubes and lines will be removed.

You will be moved from the ICU after a day or so. Your doctor may choose to put you in a normal hospital room or an intermediate care unit, where you may begin cardiac rehabilitation. There are several phases that one will go though. As your incision heals watch for redness, swelling or increasing pain. Generally, your incision will feel better in a few days.

Recovery from any surgery varies for each patient. Most patients start feeling better and gradually increase their activity in about four to six weeks. It is important in the post-operative phase to follow your doctor’s instructions closely and to report any problems you might have (abnormal pain, signs of infection) to him or her immediately. We generally ask patients to forgo driving for 2 weeks and heavy lifting (anything heavier that a gallon of milk) for 6-8 weeks.