By Jamil Aboulhosn, MD and Arwa Saidi, MB, BCh, MEd, FACC

Congenital heart defects are the most common birth defect, affecting one percent of babies. More than 90 percent of these children are now surviving to adulthood; consequently, there are now almost 1.5 million adults with congenital heart disease (CHD) living in the United States. This is one of the great success stories in the history of medicine. Before the advent of the heart lung machine in the 1950s, which allowed surgeons to operate on defects within the heart, most babies born with complex CHD did not survive to reach adulthood. It was through the creativity, diligence, and commitment of physicians, researchers, nurses and surgeons that this miraculous change in outcomes occurred.

These heart defects range from mild (such as a small hole in the heart) to complex (such as a blue baby with three instead of four heart chambers). The majority of patients with complex forms of CHD have symptoms and are diagnosed early in infancy or childhood. Those with mild defects may not develop symptoms or be diagnosed until later in life. These symptoms usually include exercise intolerance, shortness of breath, irregular heart rhythm, or lower extremity swelling.

Unfortunately, the vast majority of adult CHD (ACHD) patients are not under the care of an ACHD specialist. There are numerous reasons for this, which include lack of access to specialized care, lack of awareness of specialized care, loss to follow-up after the pediatric period, or being under the care of a non-specialist. So when these patients develop symptoms, they usually present to their primary care providers, emergency room physicians, obstetricians and gynecologists or other non-ACHD physicians. Recognition of signs and symptoms of CHD by these medical providers allows for timely and appropriate delivery of care.

There are numerous acceptable ways to classify CHD but one can simplistically group ACHD patients into one of two categories:

Patients with Known CHD:

In the United Sates, the majority of ACHD patients were followed by a pediatric cardiologist during childhood. However, most patients, especially those with mild forms of CHD, do not end up transitioning to an ACHD specialist after aging out of pediatric care. Over the years, many have been lost to care and their cardiac follow up often becomes sporadic because they are feeling well, did not have insurance, relocated or did not establish cardiac care in adulthood.

Although many patients consider themselves "cured" because of their prior surgery, unfortunately that is not the case. They are still at risk of developing arrhythmias, progressive valvular disease and heart failure symptoms, and may need further medical or surgical intervention. Greater awareness and recognition of the importance of ACHD follow-up will reduce the preventable complications associated with loss of care.

It is essential that patients have a basic knowledge and understanding of their CHD, what surgeries they have had, what medications they take, and what signs or symptoms to watch out for. Some adult CHD patients have low circulating oxygen levels and are "cyanotic," meaning their lips and fingers have a bluish discoloration. These patients are at increased risk of having a brain abscess, stroke, clots in the lungs, and heart valve infections. Others have normal oxygen levels but suffer from heart rhythm instability and suffer from heart failure. Many are living healthy, productive lives and are under good sub-specialized ACHD care. All patients with CHD are at risk for developing acquired medical problems such as diabetes, cancer, hypertension, etc.; they are just like the rest of us in that respect.

Patients With Previously Undiagnosed CHD:

Because of the more favorable natural history of several heart defects, some patients may not have symptoms and thus go undiagnosed until adulthood. These defects include atrial septal defect, partial anomalous pulmonary venous return, coarctation of the aorta, Ebstein's anomaly and congenitally corrected transposition of the great arteries (CC-TGA). Patients with these defects may present with symptoms during or after a pregnancy or even later in life with symptoms of heart failure and decreased exercise tolerance.

Consider a previously undiagnosed atrial septal defect, partial anomalous pulmonary venous return or Ebstein's anomaly in patients presenting with heart failure symptoms, right atrial or ventricular dilation or atrial arrhythmias. Consider a diagnosis of CC-TGA in patients with heart failure, slow heart rates due to complete heart block or a type of electrical abnormality called the Wolf Parkinson White syndrome. Patients with coarctation of the aorta may present with difficult to control hypertension despite the use of multiple antihypertensive medications. A cardiac echocardiogram, CT or MRI can help make the diagnosis.

If congenital heart disease is considered or diagnosed, further evaluation and imaging by a CHD specialist is necessary. This evaluation and management is guided by the 2018 AHA/ACC Guidelines for the Management of Adults with Congenital Heart Disease and takes the anatomical cardiac defect and the patient's symptoms into consideration.

After a diagnosis is established, collaborative care between the primary care provider and ACHD cardiologist is recommended. Patients and providers can access the Adult Congenital Heart Association website at www.ACHAHeart.org to find the adult congenital heart disease center that is closest to them, as well as a list of board certified specialists, including details about the care the center provides.

In conclusion, whether you are seeing a patient who is presenting with new symptoms or who has known CHD and has been lost to care, we urge you to think about CHD. So many patients in this country are lost to the specialized care they need.

Jamil Aboulhosn, MD, FACC, FSCAI, is the Chair of the Adult Congenital Heart Association Medical Advisory Board. He is the Streisand/American Heart Association Chair of Cardiology and Associate Professor of Medicine and Pediatrics at the David Geffen School of Medicine, University of California Los Angeles, as well as Director of the Ahmanson/UCLA Adult Congenital Heart Disease Center, Los Angeles.

Arwa Saidi, MB, BCh, MEd, FACC, is the Vice Chair of the Adult Congenital Heart Association Medical Advisory Board. She is the Director of the Adult Congenital Heart Disease Program and Professor of Medicine and Pediatrics at the University of Florida, Gainesville.

About the Adult Congenital Heart Association

The Adult Congenital Heart Association (ACHA) is a national not-for-profit organization dedicated to improving the quality of life and extending the lives of adults with congenital heart disease (CHD). ACHA serves and supports the more than one million adults with CHD, their families and the medical community--working with them to address the unmet needs of the long-term survivors of congenital heart defects through education, outreach, advocacy, and promotion of ACHD research. For more information about ACHA, contact 888-921-ACHA or visit www.ACHAHeart.org.