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Pediatric Cardiothoracic Surgery

Pediatric Cardiothoracic Surgery

Our Phone Number: 914.493.8793.

New Frontiers For Exceptional Care

A trusted, renowned team of experts offering revolutionary life-saving cardiac surgical techniques available nowhere else in the nation make Maria Fareri Children’s Hospital, a member of the Westchester Medical Center Health Network (WMCHealth), the Hudson Valley’s choice for pediatric heart surgery.

These breakthrough approaches to treating infants, children and young adults with congenital heart defects were pioneered by Khanh H. Nguyen, MD, Chief of Pediatric Cardiac Surgery at Maria Fareri Children’s Hospital, the only acute-care children’s hospital in the Hudson Valley. A small incision under the arm, providing the surgeon access to the heart, leaves an almost invisible scar, and fast-tracking protocols result in many patients leaving the hospital within three days of surgery or less. Both techniques speed patients’ recovery and return to normal activity.

Dr. Nguyen is a national leader in pediatric cardiac surgery and is well-known for performing the most complex pediatric procedures with one of the lowest mortality rates in the state of New York. He and his specialized team’s passion for the latest treatments and technology power their commitment to building trust with every patient, every day.

What Are Congenital Heart Defects?

Congenital heart defects often are life-altering or life-threatening because they often slow delivery of sufficient oxygen, via blood, throughout the body. Defects can include holes in the heart’s interior walls or blood vessels; malformed chambers or valves; how the heart functions; or a combination. All stress the heart because they inhibit how blood circulates and carries oxygen throughout the body. Causes include issues with the body’s chromosomes, which are components in cells that include DNA and make each person unique. Defects also can be random. The impacts of severe defects are typically noticed in utero or soon after the baby is born. Symptoms include slow development, breathing issues and the baby turning blue because of insufficient oxygen in the blood. Some defects may not initially be evident, but can be identified later as the child grows and exhibits swelling, a lack of stamina or other symptoms. Here is a list of heart conditions we treat:

Aortic stenosis

A narrowing of the valve on the heart’s aorta restricts blood flow through the aorta and to the rest of the body. Over time, the heart can be weakened by the continual exertion caused by the obstruction. Risk factors include high blood pressure, diabetes and kidney disease.

Atrial septal defect

The presence of a hole in the wall between the heart’s side-by-side chambers, which are called the left atrium and right atrium, inhibits proper blood flow. This defect allows oxygen-rich blood to blend with low-oxygen blood and proceed to the lungs. The additional blood can stress the lungs and increase the size of the heart’s right side while weakening it.

Coarctation of the aorta

The aorta is the major artery carrying oxygen-laden blood to the body. When the aorta narrows, it reduces blood flow where arteries branch out to carry blood to the body. The condition, which generally occurs before birth, causes the heart to work harder and can cause high blood pressure and heart damage.

Complete atrioventricular septal defect

Instead of the hearts’ four chambers being distinct, a large hole in center of the heart connects all chambers. This enables blood from the chambers and valves to mix, resulting in blood with insufficient oxygen being improperly routed through the body. In a healthy heart, oxygen-rich blood from the lungs does not mix with oxygen-poor blood.

Double inlet left ventricle

The left atrium and right atrium of the heart are improperly connected to the left ventricle. In some cases, one ventricle may be extremely small. Babies with double inlet left ventricle have an intact left ventricle pumping blood to the body, and a small right ventricle pumping blood to the lungs. Oxygen-rich blood and oxygen-poor blood combine in the left ventricle and is pumped to the lungs and body, leaving the bloodstream with insufficient oxygen.

Double outlet right ventricle

In this rare defect, the aorta connects to the right ventricle, the heart chamber that pumps oxygen-poor blood to the lungs. It is supposed to connect to the left ventricle, which normally pumps oxygen-rich blood to the body. This result: Oxygen-poor blood is sent through the circulatory system and can strain the heart. The condition is caused by ventricular septal defect, which is a hole in the wall of heart tissue called the septum, which separates the right and left ventricles.

Endocardial cushion defect

Tissue at the center of the heart improperly or incompletely develops, leaving openings where a wall should be. Those gaps result in the heart’s four chambers being joined instead of distinct, as they should be. The defect increases blood flow and pressure in the lungs; can cause heart failure from the stress; and allows oxygen-poor blood to mix with oxygen-rich blood. This causes insufficiently oxygenated blood to reach the body.

Hypoplastic left heart syndrome

The lower left chamber, called the left ventricle, is too small or not present because it did not develop. As a result, blood does not pump sufficiently. The mitral and aortic valve and aorta may be narrow or closed, preventing oxygen-laden blood from circulating.

Hypoplastic left heart syndrome

The lower left chamber, called the left ventricle, is too small or not present because it did not develop. As a result, blood does not pump sufficiently. The mitral and aortic valve and aorta may be narrow or closed, preventing oxygen-laden blood from circulating.

Interrupted aortic arch

The aorta, which is curved, has a break, or disconnection, between the top part of the aortic arch and the lower, descending aorta. This occurs because the aorta has not fully developed while the fetus is in the womb. The condition prevents the heart from sending oxygenated blood through the aorta to the body.

Mitral stenosis

Mitral stenosis is a condition in which the heart’s mitral valve does not open as widely as it should because it has become stiff, scarred or its flaps have partially or fully fused. The mitral valve connects the heart's upper left chamber to the lower left chamber. Ordinarily, the pumping of the heart opens the flaps; between each heartbeat, the flaps close so blood does not flow backward.

Patent ductus arteriosus

Newborn babies’ blood receives oxygen from the lungs; as fetuses, however, blood does not need to go to the lungs to become oxygenated because oxygen is provided via the umbilical cord. The ductus arteriosus is a hole in the aorta that allows fetuses’ blood to skip circulation to the lungs. The hole should close after birth when normal breathing begins. If the hole does not close, blood circulation is improper. “Patent” is a term meaning “open”.

Patent foramen ovale

This condition is defined by a hole in the heart between the left and right atrium that didn't close the way it should have after birth. In fetuses, blood does not go through the lungs; instead, oxygenation takes place through the umbilical cord. As the newborn begins to breathe on its own, the foramen ovale, a flap of tissue, should close and eventually seal due to the pressure of blood being pumped. The closed hole prevents blood from passing from one atrium to the other. “Patent” is a term meaning “open”.

Pulmonary atresia

Blood that ordinarily would travel from the heart’s right ventricle into the pulmonary artery and on to the lungs to receive oxygen cannot do so because the pulmonary valve did not form or did not develop correctly. The valve would normally open and close; instead, that heart tissue is solid. Immediately after birth, some blood can travel to the lungs through other natural passages within the heart and arteries, but these pathways typically seal and are not long-term alternatives for proper circulation.

Pulmonary stenosis

The pulmonary heart valve allows blood to flow from the heart’s right ventricle into the pulmonary artery and then into the lungs. However, in pulmonary stenosis, the pulmonary valve’s flaps are too thick, stiff or are fused, so they are not completely open. This obstructs blood flow, which, over time, strains the heart. In normal operation, the flaps open to allow blood to move ahead, but close quickly to prevent backward blood flow.

Single ventricle defects

These disorders affect one lower chamber of the heart. The chamber may be too small or missing a valve. When that ventricle is too small, or is missing the pulmonary or triscuspid valve, the heart has only one chamber pumping blood and lacks the strength to correctly function. This results in insufficiently oxygenated blood because the blood flow through the heart decreases. Single-ventricle defect conditions include hypoplastic left heart syndrome, pulmonary atresia and tricuspid atresia (please see definitions for these terms elsewhere in this glossary).

Tetralogy of Fallot

Four abnormalities characterize this condition: A hole between the heart’s lower chambers, called a ventricular septal defect; the valve between the heart and lungs being too narrow (pulmonary stenosis); the aorta is misplaced over the hole in the chamber walls; and the heart wall/muscle surrounding the lower right chamber is too thick because of the extra effort the heart has to endure. Heart defects cause blood to have insufficient oxygen because oxygen-rich and oxygen-poor blood mixes in the heart and is sent through the body when it should not be.

Transposition of great arteries

Abnormal development of the heart during initial stages of pregnancy results in the aorta connecting to the right ventricle and the pulmonary artery connecting to the left ventricle. This is the opposite of a heart's normal structure. As a consequence, blood is not routed to the lungs to gain oxygen, and blood with oxygen does not circulate through the body.

Tricuspid atresia

When the tricuspid heart valve, normally connecting the right atrium and right ventricle, is missing or has not developed properly, a wall of tissue where the valve would be blocks blood’s proper pathway. The result is that blood cannot travel from the right atrium to the right ventricle, and then to the lungs to become oxygenated. This condition also is marked by the right ventricle being too small, and an atrial septal defect -- a hole between the right atrium and left atrium -- exists. The hole improperly allows oxygen-poor and oxygen-rich blood to mix in the heart.

Truncus arteriosus

The presence of one large artery, instead of two, to carry blood to the lungs and body is caused when that single large vessel fails to divide during the heart’s development. The wall that divides the ventricles also does not form; that condition is called ventricular septal defect. The result is that there is no specific path for blood to proceed to the lungs for oxygen before returning to the heart to deliver oxygen to the body. In addition, the condition causes blood with oxygen to mix with blood that has not absorbed oxygen.

Vascular ring

This abnormal formation of the aorta causes blood vessels to encircle and compress the esophagus and trachea. This causes breathing and digestive complications. The condition occurs when parts of the aorta, which should disappear, persist as a fetus grows.

Ventricular septal defect

A hole in the tissue wall separating the heart’s lower two chambers results when the heart does not develop properly in the fetus. In a healthy heart, this wall keeps oxygen-rich blood from blending with oxygen-poor blood. Instead, the hole increases blood pressure and reduces oxygen to the body.

Dr. Nguyen’s under-the-arm surgical-access technique, called a right axillary incision, sets a new standard for a broad array of congenital heart-defect surgeries. The right axillary incision is revolutionary due to the procedure’s safety, effectiveness, versatility and unsurpassed aesthetic result. It spares children from an incision (and later, a sizeable scar) down the center of the chest, called a medial sternotomy, a common precursor to traditional open-heart surgery. Instead, a small horizontal incision in the armpit avoids the surgical necessity, when operating through the chest, of disturbing the breast bone and chest muscle.

Dr. Nguyen authored a research article about the right axillary incision procedure being a breakthrough in the February 2018 edition of Seminars in Thoracic and Cardiovascular Surgery, the official journal of the American Association for Thoracic Surgery. The article concluded that “The right axillary incision allows a safe and effective repair for a broad range of congenital heart defects and is a potential new standard of care for many patients.”

The publication provides cardiothoracic surgeons with cutting-edge information and insights. The axillary incision is used even during highly complex pediatric cardiac procedures. These include congenital heart problems such as atrial septal defects, Tetralogy of Fallot, tricuspid valve repair, ventricular septal defects, patent ductus arteriosus and others. The technique also is used to implant cardiac-assist devices.

Additionally, the fast-tracking program, used by the Pediatric Cardiac Surgery team, speeds patients' recovery and release from the hospital after surgery. After the procedure, a breathing tube is removed to facilitate natural breathing, which aids recuperation. 

Click on the "Conditions We Treat" tab to view a list of conditions treated for a full list of pediatric heart-related conditions and cardiac malformations treated at Maria Fareri Children’s Hospital through minimally invasive and more complex procedures.

For appointments or referrals, please call 914.493.8793.

Khanh H. Nguyen, MD, whose innovative treatments have positioned him a national leader in pediatric heart surgery, is Chief of Pediatric Cardiac Surgery at Maria Fareri Children’s Hospital, the region’s only acute-care children’s hospital and a member of the Westchester Medical Center Health Network (WMCHealth).

Dr. Nguyen, with more than three decades of experience, has performed thousands of life-saving heart surgeries. He leads a team known for its trusted, dignified, timely care. Maria Fareri Children’s Hospital is world-renowned for exceptional diagnoses, treatments and facilities – and is close to home here in the Hudson Valley. Dr. Nguyen specializes in performing the most complex pediatric cardiac procedures, and does so with one of the lowest mortality rates in the state of New York.

He has pioneered an approach to open heart surgery in infants, children and young adults using a transverse axillary incision. This small, horizontal surgical opening in the right armpit area provides access to the heart. The incision leaves an almost invisible surgical scar, and the procedure is safe and effective.

In addition to transformative surgery techniques, Dr. Nguyen also aids patients with fast-tracking protocols. These procedures, including patients assisted by a breathing tube instead of a ventilator immediately after heart surgery, result in many patients leaving the hospital within three days instead of a week or more.  

With 12 years of experience as an attending physician at Maria Fareri Children’s Hospital, Dr. Nguyen is well familiar with the hospital’s cutting-edge facilities and patient-first culture focusing on wellness, healing and the future. Overall, his reputation has earned him multiple placements in “Top Doctors” listings, as well as in New York magazine’s “Best Doctors” rankings.

International Reputation

Within the medical community, Dr. Nguyen is recognized as an innovative physician who has built a worldwide reputation for outstanding cardiac care.

For instance, he has served as a lead investigator for numerous research studies. He has authored or co-authored more than 50 peer-reviewed articles that have appeared in publications such as the Journal of Thoracic and Cardiovascular Surgery; Journal of Cardiac Surgery; Annals of Thoracic Surgery; American Journal of Cardiology; Pediatric Cardiology; Journal of the American Society of Echocardiology; Journal of Cardiothoracic and Vascular Anesthesia; and the World Journal for Pediatric and Congenital Heart Surgery.

In addition, Dr. Nguyen has been a guest reviewer for distinguished publications such as The Annals of Thoracic Surgery, The Journal of Thoracic and Cardiovascular Surgery and Congenital Heart Disease. He has been an invited lecturer two dozen times and has participated in 30 national and international medical presentations.

Dr. Nguyen’s commitment to global pediatric health has inspired eight surgical missions abroad, where he has trained surgeons and performed advanced procedures on infants and children in their home countries. His destinations include Nicaragua (2013); Vietnam (2006 and 2009), where he returned to perform surgery at the hospital where he was born; Honduras (2007); Romania (2000, 2001 and 2004); and China (1998).

For more than two decades, Dr. Nguyen has affirmed his commitment to well-being by teaching the next generation of clinical professionals as an assistant, associate and full professor of cardiothoracic surgery. He currently is Professor of Surgery at New York Medical College, the academic affiliate of Maria Fareri Children’s Hospital and Westchester Medical Center.

To learn more about Dr. Nguyen, visit the "Our Providers" tab. 

For appointments or referrals, please call 914.493.8793.

Pediatric Cardiothoracic Surgery
Maria Fareri Children’s Hospital
100 Woods Road
Valhalla, NY 10595

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Nguyen, Khanh
Nguyen, Khanh
Chief, Pediatric Cardiac Surgery
Pediatric Cardiothoracic Surgery