Coronary bypass surgery

Coronary bypass surgery is a procedure to allow blood to flow to your heart muscle despite blocked arteries. Coronary bypass surgery uses a healthy blood vessel taken from your leg, arm, chest or abdomen and connects it to the other arteries in your heart so that blood is bypassed around the diseased or blocked area. After a coronary bypass surgery, normal blood flow is restored. Coronary bypass surgery is just one option to treat heart disease.

Just like all the other organs in your body, your heart needs blood and oxygen to do its job. Coronary arteries snake across the surface of your heart, delivering a constant supply of blood and oxygen to the heart muscle. When one or more of these arteries become narrowed or blocked, blood and oxygen are reduced and heart muscle is damaged. Coronary bypass surgery can minimize this damage.

Although they rarely occur, the most common complications of coronary bypass surgery are:

• Bleeding
• Heart rhythm irregularities (arrhythmias)
• Kidney failure
• Infections of the chest wound
• Memory loss or troubles with thinking clearly, which often go away within six to 12 months
• Stroke

Your risk of developing these complications depends on your health before the surgery. Talk to your doctor to get a better idea of the likelihood of experiencing these risks.

If you're having a scheduled coronary bypass surgery, your risk of death is usually low, but still depends on your overall health. The risk is higher if the operation is done as an emergency or if you have other significant medical conditions such as emphysema, kidney disease, diabetes or peripheral vascular disease.

During the procedure
Coronary bypass surgery generally takes between three and six hours and requires general anesthesia. On average, surgeons repair two to four coronary arteries. The number of bypasses required depends on the location and severity of blockages in your heart.

Most coronary bypass surgeries are done through a large incision in the chest while blood flow is diverted through a heart-lung machine (called on-pump coronary bypass surgery).

The surgeon makes an incision down the center of the chest, along the breastbone. The rib cage is spread open to expose the heart. After the chest is opened, the heart is temporarily stopped and a heart-lung machine takes over blood circulation to the body.

The surgeon takes a section of healthy blood vessel, often from inside the chest wall (the internal mammary artery) or from the lower leg, and attaches the ends above and below the blocked artery so that blood flow is diverted (bypassed) around the narrowed portion of the diseased artery.

There are other methods your surgeon may use if you're having coronary bypass surgery:

• Off-pump or beating-heart surgery. This procedure allows surgery to be done on the still-beating heart using special equipment to stabilize or quiet the area of the heart the surgeon is working on. This type of surgery is challenging because the heart is still moving. Because of this, it's not an option for everyone. The long-term outcome of this type of procedure is not yet known, and there have been no proven benefits of this technique over standard coronary bypass using the heart-lung machine in the average patient.
• Minimally invasive surgery. In this procedure, a surgeon performs coronary bypass through a smaller incision in the chest, often with the use of robotics and video imaging that help the surgeon operate in a small area. Variations of minimally invasive surgery may be called port-access or keyhole surgery.

Once you're anesthetized, a breathing tube is inserted through your mouth. This tube attaches to a ventilator, which breathes for you during and immediately after the surgery.

After the procedure
Coronary bypass surgery is a major operation. Expect to spend a day or two in the intensive care unit after coronary bypass surgery. Here, your heart, blood pressure, breathing and other vital signs will be continuously monitored. Your breathing tube will remain in your throat for a few hours after surgery, so you won't be able to speak. You can communicate with hand gestures and notes. The breathing tube will be removed as soon as you are awake and able to breathe on your own.

Barring any complications, you'll likely be discharged from the hospital within a week, although even after you've been released, you may find it difficult to perform everyday tasks, or even walk a short distance. If, after returning home, you experience any of the following signs or symptoms, call your doctor. They could be warning signs that your chest wound is infected:

• A fever higher than 100.4 F (38 C)
• Rapid heart rate
• New or worsened pain around your chest wound
• Reddening, bleeding, or other discharge from your chest wound

Expect a recovery period of about six to 12 weeks. In most cases, you can return to work, begin exercising, and resume sexual activity after six weeks, but make sure you have your doctor's OK before doing so.

After surgery, most people have improvement or complete relief of their symptoms and remain symptom-free for as long as 10 to 15 years. Over time, however, it's likely that other arteries or even the new graft used in the bypass will become clogged, requiring another bypass or angioplasty.

Although bypass surgery improves blood supply to the heart, it doesn't cure underlying coronary artery disease. Your results and long-term outcome will depend in part on following healthy lifestyle recommendations and taking your medication as directed. Healthy lifestyle recommendations include:

• Stop smoking.
• Follow a healthy-eating plan, such as the DASH diet.
• Reduce cholesterol levels.
• Maintain a healthy weight.
• Control blood pressure.
• Manage diabetes.
• Exercise.

Are high-protein diets generally considered safe

High-protein diets are generally well tolerated by healthy adults. But a dramatic increase in protein-rich foods may be dangerous for people with liver or kidney disease because they lack the ability to get rid of the waste products of protein metabolism.

Some protein is essential to human life. Protein is found in your bones, muscles, skin, organs, blood, hormones and enzymes.

Your body can't store excess protein. During digestion and metabolism, protein is broken down into amino acids — the building blocks of protein. Your body uses these amino acids to make enzymes and other proteins. But any "extra" amino acids are stripped of nitrogen. The non-nitrogen parts of amino acids are used for energy or converted into fat, and the remaining nitrogen is eventually excreted by your kidneys and liver. These waste products have been shown to cause kidney injury, and in the presence of liver disease, excess nitrogen can cause further problems. High-protein diets may also increase the risk of kidney stones and osteoporosis. If you have kidney or liver disease or any chronic health condition, talk to your doctor before starting a new diet.

For most healthy people, a short-term high-protein diet generally isn't harmful. However, if followed long term, high-protein diets may limit other healthy foods, such as whole grains, fruits and vegetables. In addition, many high-protein foods — such as meat, milk, cheese and eggs — are also high in fat and cholesterol, which can increase your risk of heart disease, stroke and other health problems. So choose your protein sources wisely. Good choices include fish, beans, lentils and low-fat dairy products.