Bypass+Surgery


 * __How do doctors operate on and improve the health of a heart with blocked coronary arteries?__**

Coronary arteries bring blood to the heart muscle. If these arteries become blocked due to the build up of plaque, the blood flow to blood vessels in the heart becomes restricted or cut off completely. To increase blood flow to the heart muscle, or myocardium, surgeons can re-route the flow of blood to avoid the blockage in the coronary arteries. One way this can be accomplished is to remove a long vein from the leg, known as the saphenous vein. One end is sewn into the aorta while the other end is attached or "grafted" to the coronary artery below the blocked area. ~Sam Depending on how many coronary arteries are blocked, one, two (double), three (triple), or more bypass procedures may be done. However, the number of bypasses that are carried out may be influenced by other factors, such as the size, health, and location of the blocked arteries. If a coronary artery is too small, entirely affected by heart disease, or located within the heart itself, the surgeon may decide that the artery is unsuitable for surgery. There is also the risk of [|postperfusion syndrome], a neurocognitive deficit commonly associated with the surgery.

Typically, the heart is stopped for bypass surgery by using a potassium solution to depolarize the heart and not let it repolarize, and a pump oxygenator (heart-lung machine) performs the heart's functions. However, recently, surgeons have been performing bypass surgery with the heart still beating. In some patients, this may reduce the risk of complications after the surgery, as well as the need for a blood transfusion. Surgery done without the pump oxygenator is called off-pump coronary artery bypass surgery (OPCAB). This type of surgery is much harder for a surgeon to preform, so it is done less often. OPCAB surgery is a useful technique for operating on more complicated cases, such as a calcified aorta.

Before the surgery, the patient is washed with an __antibacterial soap__. Then __via drape__ is but over their chest. A scalpel is used to cut through the via drape and epidermis but a __compressed air saw__ is needed to cut through the sternum and __Xiphoid process__ (the bone at the bottom of the sternum that somewhat protects the heart). A __retractor__ is used to open up the ribs, and the __pericardial sac__, which the heart sits inside, is cut. __Cardioplesia__ is induced by injecting a __potassium solution__ in the area around the heart. The solution is also very cold, __10 degrees Celsius__, and serves to lower the temperature of the heart. The rate of cellular metabolism decreases as temperature is decreased. As a result, the heart can survive without blood at this temperature for the length of the surgery.

__TMR SURGERY__ Patients with coronary artery disease are treated with interventional procedures (angioplasty and stenting), coronary artery bypass grafting (surgery) and medications to improve blood flow to the heart muscle. If these procedures do not eliminate the symptoms of chest pain (also called angina), transmyocardial laser revascularization or TMR is another treatment option. TMR is a treatment aimed at improving blood flow to areas of the heart that were not treated by angioplasty or surgery. A special carbon dioxide (CO2) laser is used to create small channels in the heart muscle, improving blood flow in the heart. TMR is a surgical procedure. The procedure is performed through a small left chest incision or through a midline incision. Frequently, it is performed with coronary artery bypass surgery, but occasionally it is performed independently. Once the incision is made, the surgeon exposes the heart muscle. A laser handpiece is then positioned on the area of the heart to be treated. A special high-energy, computerized carbon dioxide (CO2) laser, called the CO2 Heart Laser 2, is used to create between 20 to 40 one-millimeter-wide channels (about the width of the head of a pin) in the oxygen-poor left ventricle (left lower pumping chamber) of the heart. The doctor determines how many channels to create during the procedure. The outer areas of the channels close, but the inside of the channels remain open inside the heart to improve blood flow. The CO2 Heart Laser 2 uses a computer to direct laser beams to the appropriate area of the heart in between heartbeats, when the ventricle is filled with blood and the heart is relatively still. This helps to prevent electrical disturbances in the heart. Clinical evidence suggests blood flow is improved in two ways: TMR usually takes one to two hours. The procedure may last longer if it is combined with other heart procedures.
 * What is TMR?**
 * **How does TMR work?** ||
 * [[image:http://www.clevelandclinic.org/heartcenter/images/guide/disease/cad/tmr_proc1.jpg width="200" height="203" align="center" caption="TMR procedure"]] ||
 * **Handpiece is placed outside of the heart** ||
 * [[image:http://www.clevelandclinic.org/heartcenter/images/guide/disease/cad/tmr_proc2.jpg width="200" height="197" align="center"]] ||
 * **Laser is synchronized with heartbeat to create 20 to 40 channels** ||
 * [[image:http://www.clevelandclinic.org/heartcenter/images/guide/disease/cad/tmr_proc3.jpg width="200" height="195" align="center"]] ||
 * **Clinical evidence suggests channels heal on the outside but remain open on the inside. It is believed that new blood vessels are formed along with the channels.** ||
 * 1) The channels act as bloodlines. When the ventricle pumps or squeezes oxygen-rich blood out of the heart, it sends blood through the channels, restoring blood flow to the heart muscle.
 * 2) The procedure may promote angiogenesis, or growth of new capillaries (small blood vessels) that help supply blood to the heart muscle.