A cardiovascular shunt is an abnormal pattern of blood circulation between the right and left sides of the heart or between the systemic and pulmonary vessels. A congenital shunt is present at birth. The circulatory system has a normal pathway for blood distribution in which every heart beat provides freshly oxygenated blood to the body. When a shunt is present this normal flow of blood may not occur. There are two main groups of shunts, acyanotic shunts and cyanotic shunts. The most common congenital cardiovascular shunts are acyanotic and known as atrial septal defects. Congenital cardiovascular shunts are the most common congenital heart defects, affecting roughly 1% of all births that have some type of congenital heart problem.

Intracardiac shunts, right-left shunt, left-right shunt or bidirectional shunt, atrial septal defects, congenital heart defect, congenital heart anomaly

A congenital cardiovascular shunt is present at birth and result from abnormal embryo development.

Symptoms of cardiovascular shunts are dependent on the severity of the abnormal blood flow and the location of the shunt. Sometime the condition is asymptomatic, especially in childhood, although symptoms may appear in adolescence or adulthood. Symptoms of acyanotic shunts: Irregular heartbeats or palpitations Dizziness Shortness of breath and tiring easily Symptoms for more serious cyantonic shunts include: A bluish discoloration of the skin called cyanosis Difficulty breathing Coughing up blood Clubbing of the fingernails or toenails

Treatment depends on the type and location of the shunt and range from clinical observation to surgical intervention. Small acyanotic shunts often do not need treatment and may close on there own over time. Larger acyanotic shunts need to be closed surgically to avoid complications. Cyanotic shunts, which are more serious and have a higher rate of mortality, often require surgery to correct the defect.

In all cases of congenital cardiovascular shunts close observation and timely intervention are critical. The prognosis ranges from living a normal life to potentially fatal. Acyanotic shunts are less serious than cyanotic shunts and often close on their own over time. Larger ones may require surgery to repair, but if proper treatment is undertaken before the onset of serious symptoms the prognosis for recovery is good. Cyanotic shunts and untreated symptomatic acyanotic shunts have a worse prognosis. If severe pulmonary hypertension develops or if there is permanent damage to the blood vessels in the lungs a heart or lung transplant may be necessary. When severe cyanotic anomalies are present soon after birth immediate surgery is needed in order to increase the chance of survival.

Most shunts are benign and do not cause complications. In severe cases of cyanotic shunts possible complications can be recurrent infections, pulmonary hypertension, right side heart failure, Eisenmenger syndrome, infections in the heart valves or linings of the heart and disturbances in the heart rhythm. Death is possible in severe cases.