Heart Surgery for Congenital Defects

Definition
Purpose
Demographics
Description
Diagnosis/Preparation
Aftercare
Risks
Morbidity and mortality rates
Alternatives

Definition

Heart surgery for congenital defects consists of a variety of surgical procedures that are performed to repair the many types of heart defects that may be present at birth and can go undiagnosed into adulthood.

Purpose

Heart surgery for congenital defects is performed to repair a defect, providing improved blood flow to the pulmonary and systemic circulations and better oxygen delivery to the body. Congenital heart defects that are symptomatic at birth must be treated with palliative or complete surgical repair. Defects that are not symptomatic at birth may be discovered later in life, and will be treated to relieve symptoms by palliative or complete surgical repair. Surgery is recommended for congenital heart defects that result in a lack of oxygen, a poor quality of life, or when a patient fails to thrive. Even lesions that are asymptomatic may be treated surgically to avoid additional complications later in life.

KEY TERMS

Atresia— Lack of development. In tricuspid atresia, the triscupid valve has not developed. In pulmonary atresia, the pulmonary valve has not developed.

Coarctation of the aorta— A congenital defect in which severe narrowing or constriction of the aorta obstructs the flow of blood.

Congenital heart defects— Congenital (conditions that are present at birth) heart disease includes a variety of defects that occur during fetal development.

Cyanotic— Inadequate oxygen in the systemic arterial circulation.

Mitral valve— The heart valve connecting the left atrium and the left ventricle.

Patent ductus arteriosus— A congenital defect in which the temporary blood vessel connecting the left pulmonary artery to the aorta in the fetus fails to close in the newborn.

Pulmonary valve— The heart valve connecting the left atrium and the pulmonary arteries.

Septal defects— Openings in the septum, the muscular wall separating the right and left sides of the heart. Atrial septal defects are openings between the two upper heart chambers and ventricular septal defects are openings between the two lower heart chambers.

Stenosis— A narrowing of the heart’s valves.

Tetralogy of Fallot— A cyanotic defect in which the blood pumped through the body has too little oxygen. Tetralogy of Fallot includes four defects: a ventricular septal defect, narrowing at or beneath the pulmonary valve, infundibular pulmonary stenosis (obstruction of blood flow out of the right ventricle through the pulmonary valve), and overriding aorta (the aorta crosses the ventricular septal defect into the right ventricle).

Transposition of the great vessels— A cyanotic defect in which the blood pumped through the body has too little oxygen because the pulmonary artery receives its blood incorrectly from the left ventricle and the aorta incorrectly receives blood flow from the right ventricle.

Tricuspid valve— The heart valve connecting the right atrium and right ventricle.

Demographics

Congenital heart disease is estimated to involve less than 1% of all live births. As some defects are not found until later in life, or may never be diagnosed, this number may actually be higher. Many congenital defects are often incompatible with life leading to miscarriage and stillbirths. During a child’s first year of life, the most common defects that are symptomatic include ventricular septal defect (VSD), transposition of the great vessels (TGV), tetralogy of Fallot, coarctation of the aorta, and hypoplastic left heart syndrome. Premature infants have an increased presentation of VSD and patent ductus arteriosus. Diabetic mothers have infants with a higher incidence of congenital heart defects than non-diabetic mothers. Abnormal chromosomes increase the incidence of congenital heart defects. Specific to trisomy 21 (Down syndrome), 23-56% of infants have a congenital heart defect.

Description

Congenital heart defects can be named by a number of specific lesions, but may have additional lesions. Classification best describes lesions by the amount of pulmonary blood flow (increased or decreased pulmonary blood flow) or the presence of an obstruction to blood flow. The dynamic circulation of the newborn as well as the size of the defect will determine the symptoms. Recommended ages for surgery for the most common congenital heart defects are:

• atrial septal defects: during the preschool years
• patent ductus arteriosus: between ages one and two
• coarctation of the aorta: in infancy, if it is symptomatic, at age four otherwise
• tetralogy of Fallot: age varies, depending on the patient’s symptoms
• transposition of the great arteries: often in the first weeks after birth, but before the patient is 12 months old

Surgical procedures seek to repair the defect and restore normal pulmonary and systemic circulation. Sometimes, multiple, serial surgical procedures are necessary.

Many congenital defects are often associated so that the surgical procedures described may be combined for complete repair of a specific congenital defect.

Repair for simple cardiac lesions can be performed in the cardiac catheterization lab. Catheterization procedures include balloon atrial septostomy and balloon valvuloplasty. Surgical procedures include arterial switch, Damus-Kaye-Stansel procedure, Fontan procedure, Ross procedure, shunt procedure, and venous switch or intra-atrial baffle.

Catheterization procedures

Balloon atrial septostomy and balloon valvuloplasty are cardiac catheterization procedures. Cardiac catheterization procedures can save the lives of critically ill neonates and, in some cases, eliminate or delay more invasive surgical procedures. It is expected that catheterization procedures will continue to replace more types of surgery for congenital heart defects in the future. A thin tube called a catheter is inserted into an artery or vein in the leg, groin, or arm and threaded into the area of the heart that needs repair. The patient receives a local anesthetic at the insertion site. General anesthetic or sedation may be used.

BALLOON ATRIAL SEPTOSTOMY. Balloon atrial septostomy is the standard procedure for correcting transposition of the great arteries; it is sometimes used in patients with mitral, pulmonary, or tricuspid atresia.(Atresia is lack of or poor development of a structure.) Balloon atrial septostomy enlarges the atrial septal opening, which normally closes in the days following birth. A special balloon-tipped catheter is inserted into the right atrium and passed into the left atrium. The balloon is inflated in the left atrium and pulled back across the septum to create a larger opening in the atrial septum.

BALLOON VALVULOPLASTY. Balloon valvuloplasty uses a balloon-tipped catheter to open a stenotic (narrowed) heart valve, improving the flow of blood through the valve. It is the procedure of choice in pulmonary stenosis and is sometimes used in aortic and mitral stenosis. A balloon is placed beyond the valve, inflated, and pulled backward across the valve.

Surgical procedures

These procedures are performed under general anesthesia. Some require the use of a heart-lung machine, which takes over for the heart and lungs during the procedure, providing cardiopulmonary bypass. The heart-lung machine can cool the body to reduce the need for oxygen, allowing deep hypothermic circulatory arrest (DHCA) to be performed. DHCA benefits the surgeon by creating a bloodless surgical field.

ARTERIAL SWITCH. Arterial switch is performed to correct transposition of the great vessels, where the position of the pulmonary artery and the aorta are reversed. The procedure involves connecting the aorta to the left ventricle and the pulmonary artery to the right ventricle.

DAMUS-KAYE-STANSEL PROCEDURE. Transposition of the great vessels can also be corrected by the Damus-Kaye-Stansel procedure, in which the pulmonary artery is cut in two and connected to the ascending aorta and right ventricle.

VENOUS SWITCH. For transposition of the great vessels, venous switch creates a tunnel inside the atrio to redirect oxygen-rich blood to the right ventricle and aorta and venous blood to the left ventricle and pulmonary artery. This procedure differs from the arterial switch and Damus-Kaye-Stansel procedures in that blood flow is redirected through the heart.

FONTAN PROCEDURE. For tricuspid atresia and pulmonary atresia, the Fontan procedure connects the right atrium to the pulmonary artery directly or with a conduit, and the atrial septal defect is closed.

PULMONARY ARTERY BANDING. Pulmonary artery banding is narrowing the pulmonary artery with a band to reduce blood flow and pressure in the lungs. It is used for temporary repair of ventricular septal defect, atrioventricular canal defect, and tricuspid atresia. Later, the band can be removed and the defect corrected with a complete repair once the patient has grown.

ROSS PROCEDURE. To correct aortic stenosis, the Ross procedure grafts the pulmonary artery to the aorta.

SHUNT PROCEDURE. For tetralogy of Fallot, tricuspid atresia, or pulmonary atresia, the shunt procedure creates a passage between blood vessels, directing blood flow into the pulmonary or systemic circulations.

OTHER TYPES OF SURGERY. Surgical procedures are also used to treat common congenital heart defects. To close a medium to large ventricular or atrial septal defect, it is recommended that it be sutured or covered with a Dacron patch. For patent ductus arteriosus, surgery consists of dividing the ductus into two and tying off the ends. If performed within the child’s first few years, there is practically no risk associated with this operation. Surgery for coarctation of the aorta involves opening the chest wall, removing the defect, and reconnecting the ends of the aorta. If the defect is too long to be reconnected, a Dacron graft is used to replace the missing piece.

Diagnosis/Preparation

Before surgery for congenital heart defects, the patient will receive a complete evaluation, which includes a physical exam, a detailed family history, a chest x ray, an electrocardiogram, an echocardiogram, and usually, cardiac catheterization. Blood tests will be performed to measure formed blood elements, electrolytes, and blood

WHO PERFORMS THIS PROCEDURE AND WHERE IS IT PERFORMED?

Pediatric cardiologists and cardiac surgeons specialize in treatment of congenital defects. Hospitals dedicated to the care of children may provide cardiac surgery services. Congenital defects diagnosed at birth may require immediate transport of the infant to a facility that can provide timely treatment.

glucose. Additional tests for sickle cell and digoxin levels may be performed, if applicable. For six to eight hours before the surgery, the patient cannot eat or drink anything.

Aftercare

After heart surgery for congenital defects, the patient goes to an intensive care unit for continued cardiac monitoring. The patient may also require continued ventilator support. Chest tubes allow blood to bedrained from inside the chest as the surgical site heals. Pain medications will be continued, and the patient may remain under general anesthetic. Within 24 hours, the chest tubes and ventilation may be discontinued. Any cardiac drugs used to help the heart perform better will be adjusted appropriate with the patient’s condition.

For temporary procedures, additional follow-up with the physician will be required to judge timing for complete repair. In the meantime, the patient should continue to grow and thrive normally. Complete repair requires follow-up with the physician initially to judge the adequacy of repair, but thereafter will be infrequent with good prognosis. The child should be made aware of any procedure to be communicated for future medical care in adulthood.

Risks

Depending on the institution and the type of congenital defect repair, many risks can be identified, including shock, congestive heart failure, lack of oxygen or too much carbon dioxide in the blood, irregular heartbeat, stroke, infection, kidney damage, lung blood clot, low blood pressure, hemorrhage, cardiac arrest, and death. These risks should not impede the surgical procedure, as death is certain without surgical treatment. Neurological dysfunction in the postoperative period occurs in as much as 25% of surgical patients. Seizures are expected in 20% of cases, but are usually limited with no long-

QUESTIONS TO ASK THE DOCTOR

• What type of congenital defect has been diagnosed?
• What type of palliative and corrective surgical options are available, and what are the risks associated with each?
• Where can more information about the congenital defect and its surgical procedures be found?
• When will the repair be made?
• How many procedures of this type has the surgeon completed, and what are the surgeon-specific outcome statistics?
• What type of care will the child require until the repair can be made?
• What types of limitations are expected prior to and after the surgical procedure?
• What type of mental health support is provided for parents or caregivers?
• What type of continued care is provided for after the hospital stay?
• What type of financial support is available for the family and caregivers?

term effects. Additional risks include blood transfusion reactions and blood-borne pathogens.

Morbidity and mortality rates

Use of cardiopulmonary bypass has associated risks not related to the congenital defect repair. Procedures performed in association with cardiac catheterization have excellent long-term results, with an associated mortality of 2–4% of procedures. The Fontan procedure carries a survival rate of over 90%. Surgical procedures to repair coarctation of the aorta, in uncomplicated cases, has a risk of operative mortality from 1–2%.

Alternatives

Alternatives are limited for this patient population. Cardiac transplant is an option, but a limited number of organ donors restrict this treatment. Ventricular-assist devices and total artificial heart technology are not yet a suitable option. Temporary procedures do allow additional growth of the patient prior to corrective surgery, allowing them to gain strength and size before treatment.

Resources

BOOKS

“Congenital Heart Disease.” In Current Medical Diagnosis and Treatment, 37th edition, edited by Stephen McPhee, et al. Stamford: Appleton & Lange, 1997.

Davies, Laurie K., and Daniel G. Knauf. “Anesthetic Management for Patients with Congenital Heart Disease.” In A Practical Approach to Cardiac Anesthesia, 3rd edition, edited by Frederick A. Hensley, Jr., Donal E. Martin, and Glenn P. Gravlee. Philadelphia, PA: Lippincott Williams & Wilkins, 2000.

DeBakey, Michael E., and Antonio M. Gotto Jr. “Congenital Abnormalities of the Heart.” In The New Living Heart. Holbrook, MA: Adams Media Corporation, 1997.

Park, Myung K. Pediatric Cardiology for Practitioners, 3rd edition. St. Louis: Mosby, 1996.

Texas Heart Institute. “Congenital Heart Disease.” In Texas Heart Institute Heart Owners Handbook. New York: John Wiley & Sons, 1996.

PERIODICALS

Hicks, George L. “Cardiac Surgery.” Journal of the American College of Surgeons, 186, no. 2 (February 1998): 129–132.

Rao, P. S. “Interventional Pediatric Cardiology: State of the Art and Future Directions.” Pediatric Cardiology, 19 (1998): 107–124.

ORGANIZATIONS

American Heart Association. 7320 Greenville Ave., Dallas, TX75231. (214) 373-6300. http://www.americanheart.org.

Children’s Health Information Network. 1561 Clark Drive, Yardley, PA 19067. (215) 493-3068. http://www.tchin.org.

Congenital Heart Anomalies Support, Education &Resources, Inc. 2112 North Wilkins Road, Swanton, OH 43558. (419) 825-5575. http://www.csun.edu/~hfmth006/chaser.

Texas Heart Institute. Heart Information Service. P.O. Box 20345, Houston, TX 77225-0345. http://www.tmc.edu/thi.

Lori De Milto

Allison J. Spiwak, MSBME

Heart Surgery for Congenital Defects

Definition

A variety of surgical procedures that are performed to repair the many types of heart defects that may be present at birth.

Purpose

Heart surgery for congenital defects is performed to repair a defect as much as possible and improve the flow of blood and oxygen to the body. While congenital heart defects vary in their severity, most require surgery. Surgery is recommended for congenital heart defects that result in a lack of oxygen, a poor quality of life, or a patient who does not thrive. Some types of congenital heart defects that don't cause symptoms are treated surgically because they can lead to serious complications.

Precautions

There are many types of surgery for congenital heart defects and many considerations in the decision to operate. The patient's cardiologist or surgeon will discuss these issues on an individual basis.

Description

There are many types of congenital heart defects. Most obstruct the flow of blood in the heart, or the vessels near it, or cause an abnormal flow of blood through the heart. Rarer types include newborns born with one ventricle, one side of the heart that is not completely formed, or the pulmonary artery and the aorta coming out of the same ventricle. Most congenital heart defects require surgery during infancy or childhood. Recommended ages for surgery for the most common congenital heart defects are:

• atrial septal defects: during the preschool years
• patent ductus arteriosus: between ages one and two
• coarctation of the aorta: in infancy, if it's symptomatic, at age four otherwise
• tetralogy of Fallot: age varies, depending on the patient's signs and symptoms
• transposition of the great arteries: often in the first weeks after birth, but before the patient is 12 months old

Surgical procedures seek to repair the defect as much as possible and restore circulation to as close to normal as possible. Sometimes, multiple, serial, surgical procedures are necessary. Smaller congenital heart defects can now be repaired in a cardiac catheterization lab instead of an operating room. Catheterization procedures include balloon atrial septostomy and balloon valvuloplasty. Surgical procedures include arterial switch, Damus-Kaye-Stansel procedure, Fontan procedure, Ross procedure, shunt procedure, and venous switch or intra-atrial baffle.

Catheterization procedures

Balloon atrial septostomy and balloon valvuloplasty are cardiac catheterization procedures. Cardiac catheterization procedures can save the lives of critically ill neonates and in some cases eliminate or delay more invasive surgical procedures. It is expected that catheterization procedures will continue to replace more types of surgery for congenital heart defects in the future. A thin tube called a catheter is inserted into an artery or vein in the leg, groin, or arm and threaded into the area of the heart which needs repair. The patient receives a local anesthetic at the insertion site and is awake but sedated during the procedure.

BALLOON ATRIAL SEPTOSTOMY. Balloon atrial septostomy is the standard procedure for correcting transposition of the great arteries; it is sometimes used in patients with mitral, pulmonary, or tricupsid atresia (atresia is a defect that causes the blood to carry too little oxygen to the body). Balloon atrial septostomy enlarges the atrial opening. A special balloon-tipped catheter is inserted into the right atrium and inflated to create a large opening in the atrial septum.

BALLOON VALVULOPLASTY. Balloon valvuloplasty uses a balloon-tipped catheter to open a narrowed heart valve, improving the flow of blood. It is the procedure of choice in pulmonary stenosis and is sometimes used in aortic stenosis. Balloons made of plastic polymers are placed at the end of the catheter and inflated to relieve the obstruction in the heart valve. Long-terms results are excellent in most cases. The operative death rate is 2-4%.

Surgical procedures

These procedures are performed under general anesthesia. Some require the use of a heart-lung machine, which cools the body to reduce the need for oxygen and takes over for the heart and lungs during the procedure.

ARTERIAL SWITCH. Arterial switch is performed to correct transposition of the great arteries, where the position of the pulmonary artery and the aorta are reversed. The procedure involves connecting the aorta to the left ventricle and the pulmonary artery to the right ventricle.

DAMUS-KAYE-STANSEL PROCEDURE. Transposition of the great arteries can also be corrected by the Damus-Kaye-Stansel procedure, in which the pulmonary artery is cut in two and connected to the ascending aorta and right ventricle.

FONTAN PROCEDURE. For tricuspid atresia and pulmonary atresia, the Fontan procedure connects the right atrium to the pulmonary artery directly or with a conduit, and the atrial defect is closed. Survival is over 90%.

PULMONARY ARTERY BANDING. Pulmonary artery banding is narrowing the pulmonary artery with a band to reduce blood flow and pressure in the lungs. It is used for ventricular septal defect, atrioventricular canal defect, and tricuspid atresia. Later, the band can be removed and the defect corrected with open heart surgery.

ROSS PROCEDURE. To correct aortic stenosis, the Ross procedure grafts the pulmonary artery to the aorta.

SHUNT PROCEDURE. For Tetralogy of Fallot, tricuspid atresia, or pulmonary atresia, the shunt procedure creates a passage between blood vessels, sending blood into parts of the body that need it.

VENOUS SWITCH. For transposition of the great arteries, venous switch creates a tunnel inside the atria to re-direct oxygen-rich blood to the right ventricle and aorta and venous blood to the left ventricle and pulmonary artery.

OTHER TYPES OF SURGERY. These surgical procedures are also used to treat common congenital heart defects. A medium to large ventricular or atrial septal defect can be closed by suturing it or covering it with a Dacron patch. For patent ductus arteriosus, surgery consists of dividing the ductus into two and tying off the ends. If performed within the patient's first few years, there is practically no risk associated with this operation. Surgery for coarctation of the aorta involves opening the chest wall, removing the defect, and reconnecting the ends of the aorta. If the defect is too long to be reconnected, a Dacron graft is used to replace the missing piece. In uncomplicated cases, the risk of the operation is 1-2%.

Preparation

Before surgery for congenital heart defects, the patient will receive a complete evaluation, which includes a physical exam, a detailed family history, a chest x ray, an electrocardiogram, an echocardiogram, and usually cardiac catheterization. For six to eight hours before the surgery, the patient cannot eat or drink anything. An electrocardiogram shows the heart's activity and may reveal a lack of oxygen. Electrodes covered with conducting jelly are placed on the patient's chest, arms, and legs and the heart's impulses are traced on paper. An echocardiogram uses sound waves to create an image of the heart's chambers and valves. Gel is applied to a hand-held transducer and then pressed against the patient's chest. Cardiac catheterization is an invasive diagnostic technique used to evaluate the heart in which a long tube is inserted into a blood vessel and guided into the heart. A contrast solution is injected to make the heart visible on x rays.

Aftercare

After heart surgery for congenital defects, the patient goes to an intensive care ward where he or she is connected to a variety of tubes and monitors, including a ventilator. Patients are monitored every 15 minutes until vital signs are stable. Heart sounds, oxygenation, and the electrocardiogram are monitored. Chest tubes will be checked to ensure that they're draining properly and there is no hemorrhage. Pain medications will be administered. Complications such as stroke, lung blood clots, and reduced blood flow to the kidneys will be watched for. After the ventilator and breathing tube are removed, chest physical therapy and exercises to improve circulation will be started.

Risks

Complications from heart surgery for congenital defects can be severe. They include shock, congestive heart failure, lack of oxygen or too much carbon dioxide in the blood, irregular heartbeat, stroke, infection, kidney damage, lung blood clot, low blood pressure, hemorrhage, cardiac arrest, and death.

Resources

ORGANIZATIONS

American Heart Association. 7320 Greenville Ave. Dallas, TX 75231. (214) 373-6300. 〈http://www.americanheart.org〉.

Children's Health Information Network. 1561 Clark Drive, Yardley, PA 19067. (215) 493-3068. 〈http://www.tchin.org〉.

Congenital Heart Anomalies Support, Education & Resources, Inc. 2112 North Wilkins Road, Swanton, OH 43558. (419) 825-5575. 〈http://www.csun.edu/∼hfmth006/chaser〉.

Texas Heart Institute. Heart Information Service. PO Box 20345, Houston, TX 77225-0345. 〈http://www.tmc.edu/thi〉.

KEY TERMS

Atresia— A congenital defect in which the blood pumped through the body has too little oxygen. In tricuspid atresia, the baby lacks a triscupid valve. In pulmonary atresia, a pulmonary valve is missing.

Coarctation of the aorta— A congenital defect in which severe narrowing or constriction of the aorta obstructs the flow of blood.

Congenital heart defects— Congenital means conditions which are present at birth. Congenital heart disease includes a variety of defects that babies are born with.

Patent ductus arteriosus— A congenital defect in which the temporary blood vessel connecting the left pulmonary artery to the aorta in the fetus doesn't close in the newborn.

Septal defects— These are holes in the septum, the muscle wall separating the right and left sides of the heart. Atrial septal defects are openings between the two upper heart chambers and ventricular septal defects are openings between the two lower heart chambers.

Stenosis— A narrowing of the heart's valves. This congenital defect can occur in the pulmonary (lung) or aortic (the main heart artery) valve.

Tetralogy of Fallot— A cyanotic defect in which the blood pumped through the body has too little oxygen. Tetralogy of Fallot includes four defects: a large hole between the ventricles, narrowing at or beneath the pulmonary valve, an overly muscular right ventricle, and an aorta over the large hole.

Transposition of the great arteries— A cyanotic defect in which the blood pumped through the body has too little oxygen. The pulmonary artery and the aorta are reversed.

Heart surgery for congenital defects

Definition

Heart surgery for congenitaal defects consists of a variety of surgical procedures that are performed to repair the many types of heart defects that may be present at birth and can go undiagnosed into adulthood.

Purpose

Heart surgery for congenital defects is performed to repair a defect, providing improved blood flow to the pulmonary and systemic circulations and better oxygen delivery to the body. Congenital heart defects that are symptomatic at birth must be treated with palliative or complete surgical repair. Defects that are not symptomatic at birth may be discovered later in life, and will be treated to relieve symptoms by palliative or complete surgical repair. Surgery is recommended for congenital heart defects that result in a lack of oxygen, a poor quality of life, or when a patient fails to thrive. Even lesions that are asymptomatic may be treated surgically to avoid additional complications later in life.

Demographics

Congenital heart disease is estimated to involve less than 1% of all live births. As some defects are not found until later in life, or may never be diagnosed, this number may actually be higher. Many congenital defects are often incompatible with life leading to miscarriage and stillbirths. During a child's first year of life, the most common defects that are symptomatic include ventricular septal defect (VSD), transposition of the great vessels (TGV), tetralogy of Fallot, coarctation of the aorta, and hypoplastic left heart syndrome. Premature infants have an increased presentation of VSD and patent ductus arteriosus. Diabetic mothers have infants with a higher incidence of congenital heart defects than non-diabetic mothers. Abnormal chromosomes increase the incidence of congenital heart defects. Specific to trisomy 21 (Down syndrome), 23–56% of infants have a congenital heart defect.

Description

Congenital heart defects can be named by a number of specific lesions, but may have additional lesions. Classification best describes lesions by the amount of pulmonary blood flow (increased or decreased pulmonary blood flow) or the presence of an obstruction to blood flow. The dynamic circulation of the newborn as well as the size of the defect will determine the symptoms. Recommended ages for surgery for the most common congenital heart defects are:

• atrial septal defects: during the preschool years
• patent ductus arteriosus: between ages one and two
• coarctation of the aorta: in infancy, if it is symptomatic, at age four otherwise
• tetralogy of Fallot: age varies, depending on the patient's symptoms
• transposition of the great arteries: often in the first weeks after birth, but before the patient is 12 months old

Surgical procedures seek to repair the defect and restore normal pulmonary and systemic circulation. Sometimes, multiple, serial surgical procedures are necessary.

Many congenital defects are often associated so that the surgical procedures described may be combined for complete repair of a specific congenital defect.

Repair for simple cardiac lesions can be performed in the cardiac catheterization lab. Catheterization procedures include balloon atrial septostomy and balloon valvuloplasty . Surgical procedures include arterial switch, Damus-Kaye-Stansel procedure, Fontan procedure, Ross procedure, shunt procedure, and venous switch or intra-atrial baffle.

Catheterization procedures

Balloon atrial septostomy and balloon valvuloplasty are cardiac catheterization procedures. Cardiac catheterization procedures can save the lives of critically ill neonates and, in some cases, eliminate or delay more invasive surgical procedures. It is expected that catheterization procedures will continue to replace more types of surgery for congenital heart defects in the future. A thin tube called a catheter is inserted into an artery or vein in the leg, groin, or arm and threaded into the area of the heart that needs repair. The patient receives a local anesthetic at the insertion site. General anesthetic or sedation may be used.

balloon atrial septostomy. Balloon atrial septostomy is the standard procedure for correcting transposition of the great arteries; it is sometimes used in patients with mitral, pulmonary, or tricuspid atresia. (Atresia is lack of or poor development of a structure.) Balloon atrial septostomy enlarges the atrial septal opening, which normally closes in the days following birth. A special balloon-tipped catheter is inserted into the right atrium and passed into the left atrium. The balloon is inflated in the left atrium and pulled back across the septum to create a larger opening in the atrial septum.

balloon valvuloplasty. Balloon valvuloplasty uses a balloon-tipped catheter to open a stenotic (narrowed) heart valve, improving the flow of blood through the valve. It is the procedure of choice in pulmonary stenosis and is sometimes used in aortic and mitral stenosis. A balloon is placed beyond the valve, inflated, and pulled backward across the valve.

Surgical procedures

These procedures are performed under general anesthesia. Some require the use of a heart-lung machine, which takes over for the heart and lungs during the procedure, providing cardiopulmonary bypass. The heart-lung machine can cool the body to reduce the need for oxygen, allowing deep hypothermic circulatory arrest (DHCA) to be performed. DHCA benefits the surgeon by creating a bloodless surgical field.

arterial switch. Arterial switch is performed to correct transposition of the great vessels, where the position of the pulmonary artery and the aorta are reversed. The procedure involves connecting the aorta to the left ventricle and the pulmonary artery to the right ventricle.

damus-kaye-stansel procedure. Transposition of the great vessels can also be corrected by the Damus-Kaye-Stansel procedure, in which the pulmonary artery is cut in two and connected to the ascending aorta and right ventricle.

venous switch. For transposition of the great vessels, venous switch creates a tunnel inside the atria to redirect oxygen-rich blood to the right ventricle and aorta and venous blood to the left ventricle and pulmonary artery. This procedure differs from the arterial switch and Damus-Kaye-Stansel procedures in that blood flow is redirected through the heart.

fontan procedure. For tricuspid atresia and pulmonary atresia, the Fontan procedure connects the right atrium to the pulmonary artery directly or with a conduit, and the atrial septal defect is closed.

pulmonary artery banding. Pulmonary artery banding is narrowing the pulmonary artery with a band to reduce blood flow and pressure in the lungs. It is used for temporary repair of ventricular septal defect, atrioventricular canal defect, and tricuspid atresia. Later, the band can be removed and the defect corrected with a complete repair once the patient has grown.

ross procedure. To correct aortic stenosis, the Ross procedure grafts the pulmonary artery to the aorta.

shunt procedure. For tetralogy of Fallot, tricuspid atresia, or pulmonary atresia, the shunt procedure creates a passage between blood vessels, directing blood flow into the pulmonary or systemic circulations.

other types of surgery. Surgical procedures are also used to treat common congenital heart defects. To close a medium to large ventricular or atrial septal defect, it is recommended that it be sutured or covered with a Dacron patch. For patent ductus arteriosus, surgery consists of dividing the ductus into two and tying off the ends. If performed within the child's first few years, there is practically no risk associated with this operation. Surgery for coarctation of the aorta involves opening the chest wall, removing the defect, and reconnecting the ends of the aorta. If the defect is too long to be reconnected, a Dacron graft is used to replace the missing piece.

Diagnosis/Preparation

Before surgery for congenital heart defects, the patient will receive a complete evaluation, which includes a physical exam, a detailed family history, a chest x ray , an electrocardiogram, an echocardiogram, and usually, cardiac catheterization. Blood tests will be performed to measure formed blood elements, electrolytes, and blood glucose. Additional tests for sickle cell and digoxin levels may be performed, if applicable. For six to eight hours before the surgery, the patient cannot eat or drink anything.

Aftercare

After heart surgery for congenital defects, the patient goes to an intensive care unit for continued cardiac monitoring. The patient may also require continued ventilator support. Chest tubes allow blood to be drained from inside the chest as the surgical site heals. Pain medications will be continued, and the patient may remain under general anesthetic. Within 24 hours, the chest tubes and ventilation may be discontinued. Any cardiac drugs used to help the heart perform better will be adjusted appropriate with the patient's condition.

For temporary procedures, additional follow-up with the physician will be required to judge timing for complete repair. In the meantime, the patient should continue to grow and thrive normally. Complete repair requires follow-up with the physician initially to judge the adequacy of repair, but thereafter will be infrequent with good prognosis. The child should be made aware of any procedure to be communicated for future medical care in adulthood.

Risks

Depending on the institution and the type of congenital defect repair, many risks can be identified, including shock, congestive heart failure, lack of oxygen or too much carbon dioxide in the blood, irregular heartbeat, stroke, infection, kidney damage, lung blood clot, low blood pressure, hemorrhage, cardiac arrest, and death. These risks should not impede the surgical procedure, as death is certain without surgical treatment. Neurological dysfunction in the postoperative period occurs in as much as 25% of surgical patients. Seizures are expected in 20% of cases, but are usually limited with no long-term effects. Additional risks include blood transfusion reactions and blood-borne pathogens.

Morbidity and mortality rates

Use of cardiopulmonary bypass has associated risks not related to the congenital defect repair. Procedures performed in association with cardiac catheterization have excellent long-term results, with an associated mortality of 2–4% of procedures. The Fontan procedure carries a survival rate of over 90%. Surgical procedures to repair coarctation of the aorta, in uncomplicated cases, has a risk of operative mortality from 1–2%.

Alternatives

Alternatives are limited for this patient population. Cardiac transplant is an option, but a limited number of organ donors restrict this treatment. Ventricular-assist devices and total artificial heart technology are not yet a suitable option. Temporary procedures do allow additional growth of the patient prior to corrective surgery, allowing them to gain strength and size before treatment.

Resources

books

"Congenital Heart Disease." In Current Medical Diagnosis and Treatment, 37th edition, edited by Stephen McPhee, et al. Stamford: Appleton & Lange, 1997.

Davies, Laurie K., and Daniel G. Knauf. "Anesthetic Management for Patients with Congenital Heart Disease." In A Practical Approach to Cardiac Anesthesia, 3rd edition, edited by Frederick A. Hensley, Jr., Donal E. Martin, and Glenn P. Gravlee. Philadelphia, PA: Lippincott Williams & Wilkins, 2000.

DeBakey, Michael E., and Antonio M. Gotto Jr. "Congenital Abnormalities of the Heart." In The New Living Heart. Holbrook, MA: Adams Media Corporation, 1997.

Park, Myung K. Pediatric Cardiology for Practitioners, 3rd edition. St. Louis: Mosby, 1996.

Texas Heart Institute. "Congenital Heart Disease." In Texas Heart Institute Heart Owners Handbook. New York: John Wiley & Sons, 1996.

periodicals

Hicks, George L. "Cardiac Surgery." Journal of the American College of Surgeons, 186, no. 2 (February 1998): 129–132.

Rao, P. S. "Interventional Pediatric Cardiology: State of the Art and Future Directions." Pediatric Cardiology, 19 (1998): 107–124.

organizations

American Heart Association. 7320 Greenville Ave., Dallas, TX 75231. (214) 373-6300. <http://www.americanheart.org>.

Children's Health Information Network. 1561 Clark Drive, Yardley, PA 19067. (215) 493-3068. <http://www.tchin.org>.

Congenital Heart Anomalies Support, Education & Resources, Inc. 2112 North Wilkins Road, Swanton, OH 43558. (419) 825-5575. <http://www.csun.edu/~hfmth006/chaser>.

Texas Heart Institute. Heart Information Service. P.O. Box 20345, Houston, TX 77225-0345. <http://www.tmc.edu/thi>.

Lori De Milto
Allison J. Spiwak, MSBME

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?

Pediatric cardiologists and cardiac surgeons specialize in treatment of congenital defects. Hospitals dedicated to the care of children may provide cardiac surgery services. Congenital defects diagnosed at birth may require immediate transport of the infant to a facility that can provide timely treatment.

QUESTIONS TO ASK THE DOCTOR

• What type of congenital defect has been diagnosed?
• What type of palliative and corrective surgical options are available, and what are the risks associated with each?
• Where can more information about the congenital defect and its surgical procedures be found?
• When will the repair be made?
• How many procedures of this type has the surgeon completed, and what are the surgeon-specific outcome statistics?
• What type of care will the child require until the repair can be made?
• What types of limitations are expected prior to and after the surgical procedure?
• What type of mental health support is provided for parents or caregivers?
• What type of continued care is provided for after the hospital stay?
• What type of financial support is available for the family and caregivers?

Myocardial Resection

Definition
Purpose
Demographics
Description
Diagnosis/Preparation
Aftercare
Risks
Normal results
Morbidity and mortality rates
Alternatives

Definition

Myocardial resection is a surgical procedure in which a portion of the heart muscle is removed.

Purpose

Myocardial resection is done to improve the stability of the heart function or rhythm. Also known as endocardial resection, this open-heart surgery is done to destroy or remove damaged areas. These areas can generate life-threatening heart rhythms. Conditions resulting in abnormal heart rhythms caused by reentry pathways or aberrant cells are corrected with this treatment.

Areas of the heart involved in a myocardial infarction change in contractility and function, becoming scar tissue that thins and hinders its ability to contract. Removing this diseased area can improve myocardial contractility reversing the severity of chronic heart failure. This procedure has shown promise for patients with chronic heart failure, in order to improve cardiac output and quality of life.

Demographics

Patients are not limited by age, race or sex when being evaluated for myocardial resection surgery. Patients who experience angina, congestive heart failure, arrhythmias, and pulmonary edema (fluid on the lungs) are candidates for this procedure. Contraindications—conditions in which the surgery is not recommended—include right heart failure, high pressure in the blood coming from left ventricle (lower chamber), and pulmonary hypertension (high blood pressure in the circulation around the lungs).

Description

After receiving a general anesthetic, an incision will be made in the chest to expose the heart. Cardiopulmonary bypass (to a heart-lung machine) will be instituted since this procedure requires direct visualization of the heart muscle. Since this is a true open

KEY TERMS

Arrhythmia— An abnormal heart rhythm. Examples are a slow, fast, or irregular heart rate.

Cardiac catheterization— A diagnostic procedure in which a thin tube is inserted into an artery or vein and guided to the heart using x rays. The function of the heart and blood vessels can be evaluated using this technique.

Dacron graft— A synthetic material used in the repair or replacement of blood vessels.

Ejection fraction— The amount of blood pumped out at each heartbeat, usually referred to as a percentage.

Implantable cardioverter-defibrillator— A device placed in the body to deliver an electrical shock to the heart in response to a serious abnormal rhythm.

Infarction— Tissue death resulting from a lack of oxygen to the area.

Intra-aortic balloon pump— A temporary device inserted into the femoral artery and guided up to the aorta. The small balloon helps strengthen heart contractions by maintaining improved blood pressure.

Radiofrequency ablation— A procedure in which a catheter is guided to an area of heart where abnormal heart rhythms originate. The cells in that area are killed using a mild radiofrequency energy to restore normal heart contractions.

Wolff-Parkinson-White syndrome— An abnormal, rapid heart rhythm, due to an extra pathway for the electrical impulses to travel from the atria to the ventricles.

heart procedure, the heart will be unable to pump blood during the surgery.

Arrhythmias

When the exact source of the abnormal rhythm is identified, it is removed. If there are areas around the source that may contribute to the problem, they can be frozen with a special probe. The amount of tissue removed is so small, usually only 2-3 mm, that there is no damage to the structure of the heart.

Ventricular reconstruction

Weakened myocardium (heart muscle) allows the heart to remodel and become less efficient at pumping blood. The goal is to remove the damaged region of the free wall of the left ventricle along with any involved septum. The heart is then reconstructed to provide a more elliptical structure that pumps blood more efficiently. In some instances a Dacron graft is used to replace the removed myocardium to aid in the reconstruction.

Diagnosis/Preparation

Diagnosis of arrhythmias begins with a Holter monitor that can identify the type of arrhythmia. This is followed by a cardiac catheterization to find the aberrant cells generating the arrhythmia. The patient is then recommended for open-heart surgery to remove the cells generating the arrhythmia.

Diagnosis of chronic heart failure is demonstrated by a cardiac catheterization or nuclear medicine study. During cardiac catheterization, the patient’s cardiac function will be measured by cardiac output, ejection fraction and cardiovascular pressures. A nuclear medicine study can demonstrate areas of myocardium that are damaged. Muscle that is akinetic (does not move) will be identified. This information allows the surgeon to identify candidates for myocardial resection.

This is major surgery and should be the treatment of choice only after medications have failed and the use of an implantable cardioverter-defibrillator (a device that delivers electrical shock to control heart rhythm) has been ruled out along with medical therapy.

Prior to surgery, the physician will explain the procedure and order blood tests of the formed blood elements and electrolytes.

Aftercare

Immediately after surgery, the patient will be transferred to the intensive care unit for further cardiac monitoring. Any medications to improve cardiac performance will be weaned as necessary to allow the native heart function to return. The patient will be able to leave the hospital within five days, assuming there are no complications. Complications may include the need for intra-aortic balloon pump ventricular assist device, surgical bleeding, and infection.

Risks

The risks of myocardial resection are based in large part on the patient’s underlying heart condition and, therefore, vary greatly. The procedure involves opening the heart, so the person is at risk for the complications associated with major heart surgery, such as stroke, shock, infection, and hemorrhage. Since the amount

WHO PERFORMS THIS PROCEDURE AND WHERE IS IT PERFORMED?

Electrophysiologists, cardiac surgeons and cardiologists, specially trained in cardiac electrical signaling and ventricular reconstruction have undergone specific training in these procedures. The number of patients suitable for these procedures are limited so experienced physicians should be sought to provide medical treatment.

of myocardium to remove is not precise, a patient may demonstrate little benefit in cardiac performance. If not enough or too much tissue is rmoved, the patient will continue to have heart problems.

General anesthetic with inhalation gases should be avoided as they can promote arrhythmias. Therefore, anesthesia should be limited to intravenous medications.

Normal results

Postoperative treatment for arrhythmias demonstrates 90% of patients are arrhythmia-free at the end of one year. A study of 245 patients published in 2001, demonstrated a 98% event free survival rate for patients after one year. After five years, 80% of patients had remained event free.

Morbidity and mortality rates

Cardiopulmonary bypass has an associated risk of complications separate from myocardial resection, with age greater than 70 years of age being a predictor for increased morbidity and mortality. In 1999, over 350,000 total procedures were performed using cardiopulmonary bypass.

In the study of 245 patients, ventricular reconstruction by myocardial resection was found to have an associated in-hospital mortality rate of 78.1%.

Alternatives

If myocardial resection is being performed to prevent arrhythmia generation, new techniques allow for minimally invasive procedures to be performed, including radiofrequency ablation performed in an electrophysiology laboratory with mild sedation, instead of general anesthetic.

If ventricular restoration is contraindicated, medical treatment will be continued. Mechanical

QUESTIONS TO ASK THE DOCTOR

• In the past year, how many of these procedures have been performed by the physician?
• What is the standard of care for a patient with arrhythmias/congestive heart failure/angina/pulmonary edema?
• What alternative therapies can be suggested, and what is the difference in survival outcomes at one and five years?
• Where can additional information be found about this procedure?
• What new technologies are available to assist in completing the procedure successfully?
• What are the risks associated with cardiopulmonary bypass?
• What type of post-operative course can be expected?
• How long will it be before normal activities can be reinstituted, such as driving, exercise and returning to work?

circulatory assist with a ventricular assist device may be a suitable option. Heart transplant and total artificial heart should also be explored as alternative therapies.

Resources

BOOKS

Hensley, Frederick Jr., et al. A Practical Approach to Cardiac Anesthesia, 3rd ed. Philadelphia: Lippincott Williams & Wilkins, 2003.

Libby, P. et al. Braunwald’s Heart Disease. 8th ed. Philadelphia: Saunders, 2007.

PERIODICALS

Kawaguchi AT, et al. “Left ventricular volume reduction surgery: The 4th International Registry Report 2004.” Journal of Cardiac Surgery 20, no. 6 (November 2005): 468–475.

ORGANIZATIONS

American Heart Association. 7320 Greenville Avenue, Dallas, TX 75231. (800) 242-8721 or (888) 478-7653. http://www.americanheart.org.

Dorothy Elinor Stonely

Allison J. Spiwak, MSBME

Myoglobin test seeCardiac marker tests

Myocardial resection

Definition

Myocardial resection is a surgical procedure in which a portion of the heart muscle is removed.

Purpose

Myocardial resection is done to improve the stability of the heart function or rhythm. Also known as endocardial resection, this open-heart surgery is done to destroy or remove damaged areas. These areas can generate life-threatening heart rhythms. Conditions resulting in abnormal heart rhythms caused by re-entry pathways or aberrant cells are corrected with this treatment.

Areas of the heart involved in a myocardial infarction change in contractility and function, becoming scar tissue that thins and hinders its ability to contract. Removing this diseased area can improve myocardial contractility reversing the severity of chronic heart failure. This procedure has shown promise for patients with chronic heart failure, in order to improve cardiac output and quality of life.

Demographics

Patients are not limited by age, race or sex when being evaluated for myocardial resection surgery. Patients who experience angina, congestive heart failure, arrhythmias, and pulmonary edema (fluid on the lungs) are candidates for this procedure. Contraindications—conditions in which the surgery is not recommended—include right heart failure, elevated left ventricular enddiastolic pressures, and pulmonary hypertension (high blood pressure in the circulation around the lungs).

Description

After receiving a general anesthetic, an incision will be made in the chest to expose the heart. Cardiopulmonary bypass (to a heart-lung machine) will be instituted since this procedure requires direct visualization of the heart muscle. Since this is a true open heart procedure, the heart will be unable to pump blood during the surgery.

Arrhythmias

When the exact source of the abnormal rhythm is identified, it is removed. If there are areas around the source that may contribute to the problem, they can be frozen with a special probe to further insure against dangerous heart rates. The amount of tissue removed is so small, usually only 2–3 mm, that there is no damage to the structure of the heart.

Ventricular reconstruction

Weakened myocardium (cardiac muscle) allows the heart to remodel and become less efficient at pumping blood. The goal is to remove the damaged region of the free wall of the left ventricle along with any involved septum. The heart is then reconstructed to provide a more elliptical structure that pumps blood more efficiently. In some instances a Dacron graft is used to replace the removed myocardium to aid in the reconstruction.

Diagnosis/Preparation

Diagnosis of arrhythmias begins with a Holter monitor that can identify the type of arrhythmia. This is followed by a cardiac catheterization to find the aberrant cells generating the arrhythmia. The patient is then recommended for open-heart surgery to remove the cells generating the arrhythmia.

Diagnosis of chronic heart failure is demonstrated by a cardiac catheterization or nuclear medicine study. During cardiac catheterization, the patient's cardiac function will be measured by cardiac output, ejection fraction and cardiovascular pressures. A nuclear medicine study can demonstrate areas of myocardium that are damaged. Muscle that is akinetic (does not move) will be identified. This information allows the surgeon to identify candidates for myocardial resection.

This is major surgery and should be the treatment of choice only after medications have failed and the use of an implantable cardioverter-defibrillator (a device that delivers electrical shock to control heart rhythm) has been ruled out along with medical therapy.

Prior to surgery, the physician will explain the procedure and order blood tests of the formed blood elements and electrolytes.

Aftercare

Immediately after surgery, the patient will be transferred to the intensive care unit for further cardiac monitoring. Any medications to improve cardiac performance will be weaned as necessary to allow the native heart function to return. The patient will be able to leave the hospital within five days, assuming there are no complications. Complications may include the need for intraaortic balloon pump ventricular assist device , surgical bleeding, and infection.

Risks

The risks of myocardial resection are based in large part on the patient's underlying heart condition and, therefore, vary greatly. The procedure involves opening the heart, so the person is at risk for the complications associated with major heart surgery, such as stroke, shock, infection, and hemorrhage. Since the amount of myocardium to remove is not precise, a patient may demonstrate little benefit in cardiac performance. If not enough or too much tissue is removed, the patient will continue to have heart problems.

General anesthetic with inhalation gases should be avoided as they can promote arrhythmias. Therefore, anesthesia should be limited to intravenous medications.

Normal results

Post-operative treatment for arrhythmias demonstrates 90% of patients are arrhythmia-free at the end of one year. A study of 245 patients published in 2001, demonstrated a 98% event free survival rate for patients after one year. After five years, 80% of patients had remained event free.

Morbidity and mortality rates

Cardiopulmonary bypass has an associated risk of complications separate from myocardial resection, with age greater than 70 years of age being a predictor for increased morbidity and mortality. In 1999, over 350,000 total procedures were performed using cardiopulmonary bypass.

In the study of 245 patients, ventricular reconstruction by myocardial resection was found to have an associated in-hospital mortality rate of 78.1%.

Alternatives

If myocardial resection is being performed to prevent arrhythmia generation, new techniques allow for minimally invasive procedures to be performed, including radiofrequency ablation performed in an electrophysiology laboratory with mild sedation, instead of general anesthetic.

If ventricular restoration is contraindicated, medical treatment will be continued. Mechanical circulatory assist with a ventricular assist device may be a suitable option. Heart transplant and total artificial heart should also be explored as alternative therapies.

See also Heart transplantation; Mechanical circulation support.

Resources

books

Hensley, Frederick Jr., et al. A Practical Approach to Cardiac Anesthesia, 3rd ed. Philadelphia: Lippincott Williams & Wilkins, 2003.

McGoon, Michael D., ed. Mayo Clinic Heart Book: The Ultimate Guide to Heart Health. New York: William Morrow and Co., Inc., 1993.

periodicals

Dor, Vincent, et al. "Intermediate survival and predictors of death after surgical restoration." Seminars in Thoracic and Cardiovascular Surgery 13, no. 4 (October 2001): 468–475.

organizations

American Heart Association. 7320 Greenville Avenue, Dallas, TX 75231. (800) 242-8721 or (888) 478-7653. <http://www.americanheart.org>.

Dorothy Elinor Stonely
Allison J. Spiwak, MSBME

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?

Electrophysiologists, cardiac surgeons and cardiologists, specially trained in cardiac electrical signaling and ventricular reconstruction have undergone specific training in these procedures. The number of patients suitable for these procedures are limited so experienced physicians should be sought to provide medical treatment.

QUESTIONS TO ASK THE DOCTOR

• In the past year, how many of these procedures have been performed by the physician?
• What is the standard of care for a patient with arrhythmias/congestive heart failure/angina/pulmonary edema?
• What alternative therapies can be suggested, and what is the difference in survival outcomes at one and five years?
• Where can additional information be found about this procedure?
• What new technologies are available to assist in completing the procedure successfully?
• What are the risks associated with cardiopulmonary bypass?
• What type of post-operative course can be expected?
• How long will it be before normal activities can be reinstituted, such as driving, exercise and returning to work?