A congenital cardiovascular malformation is any heart defect that develops before birth. Defects range in severity, with some never causing any problems and others being life-threatening if not treated immediately in a newborn baby. Malformations can affect the heart’s chambers, valves, and blood vessels (the major pathways that deliver blood to the heart), and can appear as a single defect or in combination with other defects. Many defects are detected before birth during routine ultrasound appointments. Some defects cause abnormal heart sounds, the sound blood makes as it passes through the heart, or cause physical symptoms, such as blue lips or rapid breathing. Heathcare providers use tools such as an EKG or x-ray to confirm a diagnosis. The most common heart malformation is a hole between the two bottom chambers of the heart (the left and right ventricle). If small, the hole may heal on its own or cause no problems, but larger holes can cause blood from the chambers to mix, which can decrease the amount of oxygen delivered to the cells, and cause high blood pressure in the lungs, and heart failure, a condition that can cause death. These types of holes require surgical repair. Talk with your baby's doctor if your baby was diagnosed with congential cardiovascular malformation to decide on the best treatment plan for your baby.