Many diseases in infants can lead to an enlarged heart, also known as cardiac hypertrophy. Congenital defects, acquired cardiac problems that occur right after birth and maternal diseases such as diabetes can cause enlarged hearts. The right or left ventricle may be enlarged, or the heart may be enlarged overall. Symptoms and prognosis for an enlarged heart vary according to the disease process, but certain signs tend to occur in most newborns.
Respiratory Signs
Most newborns usually breathe at a rate of 40 breaths per minute, but babies who have an enlarged heart usually breathe more rapidly than this. Fast breathing is called tachypnea; it occurs because the enlarged heart can't pump oxygenated blood as effectively as a normal heart. This causes the newborn to breathe faster to try to get oxygen into the bloodstream more quickly. Tachypnea may also occur if the baby goes into congestive heart failure and the lungs fill with fluid. In an effort to get more oxygen into the body, the newborn may also have nasal flaring, grunting and chest retractions when he breathes, according to South Plains College.
Cardiac Signs
Babies with enlarged hearts often have a rapid heartbeat. This occurs for the same reason as tachypnea: The heart is pumping oxygenated blood ineffectively, so it pumps faster to try to compensate. Heart murmurs may be heard in some types of disease, but they may not occur in the first few days of life. According to Heather Taylor, M.D., of the University of Alabama Medical Center, one-third of newborns with significant heart disease don't have a murmur for the first few days. Blood pressure may also be low in newborns with an enlarged heart.
Color Changes
Newborns with an enlarged heart may be ruddy if born to diabetic mothers, or pale or cyanotic (blue). The color depends on whether the baby's heart is pumping well-oxygenated blood. In some diseases, the blood might be receiving little oxygen if the heart or blood vessels connected to it are malformed. In a case such as this, the baby may be blue all over or just around the mouth, or it may be blue only during feedings or other activity. Newborns may be pale and puffy if congestive heart failure occurs, as fluid accumulates in the tissues and lungs. Sometimes, just the extremities are cool and pale due to decreased circulation.
Energy Symptoms
Activities that need any exertion at all--such as feeding, bathing or being handled--can cause a newborn with an enlarged heart to become fatigued. The baby may be too tired to eat well or may use up so many calories just on activities of daily living that he can't gain weight. Any sort of activity may also cause the newborn to sweat.
