The history of heart surgery is relatively short-lived and since many technological and scientific advances have been made during our lifetime we often are quick to take it for granted or forget just how much has truly been done in the field. It is even difficult to believe that just a century ago it was considered impossible and extremely dangerous to perform the types of surgeries and even heart transplants that are now performed many times a year.
There are many terms tossed around in conversation relating to heart surgery, such as bypass, heart valve, and open-heart surgery and people forget that these types of surgery have revolutionized cardiology in just the past fifty years.
In the United States, congenital heart failure is the number one cause of death, but the risks that were once considered extremely life-threatening can now be greatly reduced by a number of heart medications and the latest surgical techniques.
Open-heart surgery is perhaps the most intense procedure a surgeon might perform because he is basically holding his patient's life in his hands. Scientists began questioning the concept of operating on a human heart while the patient remained alive back in the early 1900's.
It wasn't until 1953 that Dr. Walton C. Lillehei (thought of as the Father of Modern Open Heart Surgery) carried out the first operation on a seven-year-old boy using a technique called Controlled Cross-Circulation. Dr. Lillehei's idea was that he could use a parent's heart to create blood flow in his patient's heart while he performed his operation. It was a success and led to many other innovations in the field.
Dr. John Gibbon, Jr. made another major leap this same year with the creation of the artificial heart and lung machine (still being used today), which would serve the functions of the heart and lungs while open heart surgery was performed. In order to maintain function of the heart with respect to the body, the heart-lung machine is comprised of a pump and an oxygenator. These devices supply blood to the rest of the body through the arteries.
Before pumping to the arteries, the impure blood entering the artificial heart enters the oxygenator, is mixed with oxygen to purify it and then is pumped to the rest of the body. This is achieved by the surgeon's incision through the chest to the heart to remove its protective covering and expose the heart. A plastic tube (called a cannula) is inserted into the right atrium. This tube is connected to the oxygenator and another tube enters the aorta in the left ventricle where the purified blood is pumped and sent to the body's organs through the arteries. This procedure is termed cardio-pulmonary bypass.
Some of the current major heart problems include angina, heart attack and irregular heartbeat. For these conditions and others, heart medications are taken, but when serious symptoms are experienced, coronary artery bypass surgery is performed. This is done through the use of vein grafts. Vein grafting involves using veins from other parts of the body (typically saphenous veins from the leg or the internal mammary artery running along the inside of the breast bone) to bypass the blockage in the coronary artery. Using the internal mammary artery, since it is less prone to blockage, reduces the risk of second surgery.
When the valves of the heart malfunction or are diseased resulting in a narrowing of the channel through which blood flows, there are two options for the surgeon during operation. He can either repair the valve or replace it. In repairing, hardened or stiffened parts of the valve are cut and separated in order to widen the valve and allow for normal blood flow, or in the case of a valve that doesn't fully close, processes of strengthening and shortening the valve will allow it to properly function.
Just recently, prosthetics have played a large part in heart valve surgery. Mechanical, man-made valves are often used, but a risk involved is the possibility of blood clots around the valve. Another option is the use of pig, cow or human donor valves, the use of which is not as long-term as the mechanical valves.
Perhaps one of the greatest accomplishments in our day is the successful procedure of heart transplant. When replacing a human heart, the patient is placed on a heart-lung machine to keep blood flowing. The patient's heart is removed except for the back walls of the atria (the upper chambers), which are opened so the new heart can be sewn into place. The blood vessels are then connected, the heart warms up and begins beating, and the heart-lung machine is removed. Dr. Christiaan Barnard first did this in South Africa in 1967. Now the number of transplants is over 2000 per year, with survival rates of one, three, and five years being 85.7, 76.7, and 69.5 percent, respectively.
The practical applications of modern technology are now reaching cardiac surgery and the future is much anticipated. While the methods currently employed by surgeons are being refined, there is a vast frontier of medical innovations waiting to be embarked upon. In our lifetime we will see extraordinary advances in this field with the incorporation of robotics, minimally invasive surgery and precise virtual surgery.
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