Causes

The exact cause of any one congenital heart defect is rarely identified. However, most experts believe that abnormal genes coupled with environmental factors experienced during early pregnancy lead to congenital heart defects.

Health Tips from Dr. Healy: Video: What men need to know about their cholesterol Choose another disease or condition... Allergic Rhinitis Allergies, Food Allergy & Asthma Center Alzheimer's Disease Anxiety Aortic Aneurysms Arrhythmia Arthritis, Osteo- (OA) Arthritis, Rheumatoid (RA) Asthma Atopic Dermatitis Attention Deficit Hyperactivity Disorder (ADHD) Back Pain Brain Tumor Bones, Joints & Muscles Center Breast Cancer Brain & Behavior Center Brain Tumor Cancer Center    Brain Tumor    Breast Cancer    Cancer Prevention    Clinical Trials    Colorectal Cancer    Endometrial Cancer    Living With and Beyond Cancer    Lung Cancer    Prostate Cancer    Skin Cancer Cardiomyopathy Cataracts Cholesterol Control Clinical Trials Chronic Obstructive Pulmonary Disease (COPD) Colorectal Cancer Congenital Heart Disease Congestive Heart Failure (CHF) Coronary Artery Disease (CAD) Crohn's Disease Depression Diabetes Center Diabetes, Type 1 Diabetes, Type 2 Digestive Disorders Center Eczema Endometrial Cancer Erectile Dysfunction (ED) Eye & Vision Center Fibromyalgia Food Allergies Gallstone Disease Gastroesophageal Reflux Disease (GERD) GERD Glaucoma Hay Fever Headache Heart Center Hepatitis A Hepatitis B Hepatitis C High Blood Pressure Hypertension Hypertrophic Cardiomyopathy (HCM) Impotence Insomnia Irritable Bowel Syndrome (IBS) Living With and Beyond Cancer Losing Weight Lung Cancer Macular Degeneration Memory Loss Osteoarthritis (OA) Osteoporosis Parkinson's Disease Peptic Ulcer Prediabetes Prostate Cancer Respiratory Disorders Center Restless Legs Syndrome (RLS) Rheumatoid Arthritis (RA) Sexual & Reproductive Health Center Sinusitis Skin Cancer Sleep Apnea Sleep Center Stroke Type 1 Diabetes Type 2 Diabetes Ulcerative Colitis (UC) Weight Control Congenital Heart Defects (American Heart Association): Descriptions of over 10 types of congenital heart defects Congenital Heart Defects (National Heart, Lung, and Blood Institute): The NHLBI provides succinct information about how the heart works; explains assorted defects; lists symptoms, diagnosis, and treatment Congenital Heart Information Network: C.H.I.N. is an international organization that provides reliable information, support services, and resources to families affected my congenital heart disease Adult Congenital Heart Association: The ACHA is a nonprofit organization that seeks to improve the quality of life and extend the lives of adults with congenital heart defects. Clinical Trials: Congenital Heart Disease: A service of the U.S. National Institutes of Health Email this page Print this section

The heart is one of the first organs to develop in the fetus. At approximately three weeks of gestation, a tiny tube is formed and the fetal heart begins to beat. During the next few days, the tube begins to bend and fold in on itself, forming a loop that roughly takes the shape of the heart. By the 18th week of pregnancy, this tiny tube has molded into all of the basic structures of the heart. It's possible for physicians to detect some heart defects by the 18th week of pregnancy.

Genes contain the sets of instructions that guide the process of development. If these instructions are jumbled, the heart will fail to develop normally. For example, if the instructions for developing the aortic valve are incorrect, the valve may be absent altogether, as in aortic valve atresia, or misshapen, as in aortic valve stenosis.

Scientists are on the verge of discovering the genes that are associated with numerous heart defects. Currently, more than 100 mutations in several genes have been linked with congenital heart defects. Most of these genetic links are associated with hypertrophic cardiomyopathy, but other genetic mutations have been linked to septal defects and defects in the outflow path from the heart.