Patent Ductus Arteriosus

Diagnosis

Because of the turbulent blood flow from the high-pressure aorta to the low-pressure pulmonary artery, a patent ductus arteriosus causes a characteristic heart murmur that is heard during a physical exam. Besides this telltale sign, the condition of the heart and circulation are further evaluated using one or more of the following diagnostic tests:

Echocardiogram
This procedure evaluates the structure and function of the heart by using sound waves to produce a moving picture of the heart and heart valves. An echocardiogram shows the pattern of blood flow through the PDA, determines the size of the opening and how much blood is passing through it.

Chest X-ray
With a PDA, the heart may be enlarged due to excess blood flowing through the lungs. The extra blood flow may also cause changes in the lungs that can be seen on an X-ray.

Electrocardiogram (ECG)
This test records the electrical activity of the heart, detects abnormal rhythms (arrhythmias or dysrhythmias) and detects heart muscle stress.

Cardiac catheterization
This procedure gives detailed information about the structures inside the heart. A small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin, and guided to the inside of the heart. Blood pressure and oxygen levels in the four chambers of the heart are measured, as well as in the pulmonary (lung) artery and aorta. Contrast dye is used to clearly visualize the structures inside the heart.