This is a medical question of type : exams and tests 
 How to diagnose Holes in the Heart ? 
 Doctors usually diagnose holes in the heart based on a physical exam and the results from tests and procedures. The exam findings for an atrial septal defect (ASD) often aren't obvious. Thus, the diagnosis sometimes isn't made until later in childhood or even in adulthood.
                
Ventricular septal defects (VSDs) cause a very distinct heart murmur. Because of this, a diagnosis usually is made in infancy.
                
Specialists Involved
                
Doctors who specialize in diagnosing and treating heart problems are called cardiologists. Pediatric cardiologists take care of babies and children who have heart problems. Cardiac surgeons repair heart defects using surgery.
                
Physical Exam
                
During a physical exam, your child's doctor will listen to your child's heart and lungs with a stethoscope. The doctor also will look for signs of a heart defect, such as a heart murmur or signs of heart failure.
                
Diagnostic Tests and Procedures
                
Your child's doctor may recommend several tests to diagnose an ASD or VSD. These tests also will help the doctor figure out the location and size of the defect.
                
Echocardiography
                
Echocardiography (echo) is a painless test that uses sound waves to create a moving picture of the heart. The sound waves (called ultrasound) bounce off the structures of the heart. A computer converts the sound waves into pictures on a screen.
                
Echo allows the doctor to clearly see any problem with the way the heart is formed or the way it's working.
                
Echo is an important test for both diagnosing a hole in the heart and following the problem over time. Echo can show problems with the heart's structure and how the heart is reacting to the problems. This test will help your child's cardiologist decide whether and when treatment is needed.
                
EKG (Electrocardiogram)
                
An EKG is a simple, painless test that records the heart's electrical activity. The test shows how fast the heart is beating and its rhythm (steady or irregular). It also records the strength and timing of electrical signals as they pass through the heart.
                
An EKG can detect whether one of the heart's chambers is enlarged, which can help diagnose a heart problem.
                
Chest X Ray
                
A chest x ray is a painless test that creates pictures of the structures in the chest, such as the heart, lungs, and blood vessels.
                
This test can show whether the heart is enlarged. A chest x ray also can show whether the lungs have extra blood flow or extra fluid, a sign of heart failure.
                
Pulse Oximetry
                
Pulse oximetry shows the level of oxygen in the blood. A small sensor is attached to a finger or ear. The sensor uses light to estimate how much oxygen is in the blood.
                
Cardiac Catheterization
                
During cardiac catheterization (KATH-e-ter-i-ZA-shun), a thin, flexible tube called a catheter is put into a vein in the arm, groin (upper thigh), or neck. The tube is threaded to the heart.
                
Special dye is injected through the catheter into a blood vessel or one of the heart's chambers. The dye allows the doctor to see the flow of blood through the heart and blood vessels on an x-ray image.
                
The doctor also can use cardiac catheterization to measure the pressure inside the heart chambers and blood vessels. This can help the doctor figure out whether blood is mixing between the two sides of the heart.
                
Doctors also use cardiac catheterization to repair some heart defects. For more information, go to "How Are Holes in the Heart Treated?"