Red Hot Tips Point: During open heart surgery

Sunday, June 28, 2009

After the patient is asleep, a device called the Swan-Ganz catheter is often inserted into the jugular vein (in the neck) and threaded to the pulmonary artery (which goes from the heart to the lungs). The catheter is used to measure heart function and heart and lung pressure. It can also be used to give medication and measure the oxygen levels in the blood. A breathing tube (endotracheal tube) will also be inserted into the mouth and down the windpipe (trachea) to maintain an airway. A urinary catheter is also inserted and connected to a collection bag to measure the patient’s urine output.

An 11- to 12-inch incision is made in the chest and the breastbone is split in two (full median sternotomy). A retractor is then used to pull back the breastbone and ribs in order to open up the chest. The functions of the heart, including blood flow and oxygenation, are rerouted through a heart-lung machine, so that the heart can be safely stopped during the procedure by the injection of a cooled cardioplegia solution.

The cardiac portion of the procedure then begins, according to what the particular condition requires:

Coronary artery bypass graft. To treat coronary artery disease. During CABG, a surgeon takes a segment of a healthy blood vessel (either an artery or vein) from another part of the body, and uses it to create a detour or bypass around the blocked portion of the coronary artery. As a result, oxygen-rich blood can flow more freely to nourish the heart muscle. A patient may require one, two, three or more bypasses depending on how many coronary arteries (and their main branches) are blocked. Other procedures may be combined with this surgery (e.g., replacement or repair of the heart valve closure of a heart defect).
Heart valve procedures. To repair or replace a defective valve. Defective valves that cannot be repaired are replaced with either a biological or a mechanical valve. Another type of open-heart valve procedure is a valvotomy (also known as valvulotomy, valvuloplasty or commissurotomy), where the surgeon cuts into a valve to repair damage.
Septal myomectomy. To treat hypertrophic obstructive cardiomyopathy, an inherited heart condition characterized by an abnormal growth of muscle fibers of their heart. During the procedure, a surgeon removes part of an enlarged septum, which is the muscular wall between the left and right ventricles of the heart.

Some open-heart procedures are used to correct or relieve congenital heart defects. Annually, there are about 20,000 open-heart surgeries performed on children in the United States. Infants under one year of age comprise approximately 90 percent of pediatric open-heart surgeries, which include:

Norwood procedure. A series of surgeries to treat hypoplastic left heart syndrome, in which the chambers, valves and related blood vessels on the left side of the heart are so malformed that they cannot efficiently pump blood to the rest of the body. Each open-heart surgery is done at a different age, ranging from infancy through the toddler years. The first two surgeries (Stages I and II) are used to temporarily relieve blood flow problems to and from the lungs. The third surgery (Stage III), known as the Fontan procedure, is used to further improve the circulation but cannot cure the underlying heart defects.

Arterial switch operation. To treat transposition of the great arteries (TGA), in which the aorta and the pulmonary artery are in reversed locations, resulting in oxygen-rich blood from the lungs not being able to get to the brain and the rest of the body. During the procedure, the pulmonary artery is disconnected from the pulmonic valve, which arises from the left ventricle. The aorta is disconnected from the aortic valve, which arises from the right ventricle. The aorta is then connected to the pulmonic valve, so that it is exiting from the left ventricle, as it should. The pulmonic valve is connected to the aortic valve, so that it is exiting from the right ventricle, as it should.
Rastelli procedure. To treat a number of cyanotic heart defects that restrict the normal flow of blood from the heart to the lungs. The Rastelli procedure is used when a hole in the heart is involved in the defect. The hole is patched to redirect blood flow. Some of these defects include: transposition of the great arteries (TGA) with ventricular septal defect (VSD), pulmonary stenosis, pulmonary atresia (complete closure of the pulmonic valve) with VSD and double outlet right ventricle (DORV) with pulmonary stenosis.