A color flow and doppler imaging is used to help confirm the presence as well as evaluate the severity of ASD and MS.

A chest x-ray will be given to determine the size of the heart and the blood vessels supplying blood to the lungs.

A VSD can be detected by cardiac auscultation. Classically, a VSD causes a pathognomonic holo- or pansystolic murmur. Auscultation is generally considered sufficient for detecting a significant VSD. The murmur depends on the abnormal flow of blood from the left ventricle, through the VSD, to the right ventricle. If there is not much difference in pressure between the left and right ventricles, then the flow of blood through the VSD will not be very great and the VSD may be silent. This situation occurs a) in the fetus (when the right and left ventricular pressures are essentially equal), b) for a short time after birth (before the right ventricular pressure has decreased), and c) as a late complication of unrepaired VSD. Confirmation of cardiac auscultation can be obtained by non-invasive cardiac ultrasound (echocardiography). To more accurately measure ventricular pressures, cardiac catheterization, can be performed.

A less invasive method for detecting a PFO or other ASDs than transesophagal ultrasound is transcranial Doppler with bubble contrast. This method reveals the cerebral impact of the ASD or PFO.

AVSDs can be detected by cardiac auscultation; they cause atypical murmurs and loud heart tones. Confirmation of findings from cardiac auscultation can be obtained with a cardiac ultrasound (echocardiography - less invasive) and cardiac catheterization (more invasive).

Tentative diagnosis can also be made in utero via fetal echocardiogram. An AVSD diagnosis made before birth is a marker for Down syndrome, although other signs and further testing are required before any definitive confirmation of either can be made.

Hypoplastic left heart syndrome can be diagnosed prenatally or after birth via echocardiography. Typical findings include a small left ventricle and aorta, abnormalities of the mitral and aortic valves, retrograde flow in the transverse arch of the aorta, and left-to-right flow between the atria. It is often recognized during the second trimester of pregnancy, between 18 and 24 weeks' gestation.

Congenital heart defects are now diagnosed with echocardiography, which is quick, involves no radiation, is very specific, and can be done prenatally.

Before more sophisticated techniques became available, chest x-ray was the definitive method of diagnosis. The abnormal "coeur-en-sabot" (boot-like) appearance of a heart with tetralogy of Fallot is classically visible via chest x-ray, although most infants with tetralogy may not show this finding. Absence of interstitial lung markings secondary to pulmonary oligaemia are another classic finding in tetralogy, as is the pulmonary bay sign.

Once someone is found to have an atrial septal defect, a determination of whether it should be corrected is typically made. If the atrial septal defect is causing the right ventricle to enlarge a secundum atrial septal defect should generally be closed. If the ASD is not causing problems the defect may simply checked every two or three years. Methods of closure of an ASD include surgical closure and percutaneous closure.

Drug therapy can be used to minimize risk of thromboembolism and stroke in PFO. Anticoagulants, such as warfarin, are commonly used to reduce blood clotting, whereas antiplatelet agents, such as aspirin, are used to reduce platelet aggregation and thrombosis.

In regards to the diagnosis of pulmonary atresia the body requires oxygenated blood for survival. pulmonary atresia is not threatening to a developing fetus however, because the mother's placenta provides the needed oxygen since the baby's lungs are not yet functional. Once the baby is born its lungs must now provide the oxygen needed for survival, but with pulmonary atresia there is no opening on the pulmonary valve for blood to get to the lungs and become oxygenated. Due to this, the newborn baby is blue in color and pulmonary atresia can usually be diagnosed within hours or minutes after birth.

The diagnosis of pulmonary atresia can be done via the following exams/methods: an echocardiogram, chest x-ray, EKG and an exam to measure the amount of in the body.

Although there are several classifications for VSD, the most accepted and unified classification is that of Congenital Heart Surgery Nomenclature and Database Project.

The classification is based on the location of the VSD on the right ventricular surface of the inter ventricular septum and is as follows:

Chest X-ray may also assist in diagnosis, showing left atrial enlargement.

Electrocardiography may show "P mitrale", that is, broad, notched P waves in several or many leads with a prominent late negative component to the P wave in lead V, and may also be seen in mitral regurgitation, and, potentially, any cause of overload of the left atrium. Thus, "P-sinistrocardiale" may be a more appropriate term.

Another method of measuring the severity of mitral stenosis is the simultaneous left and right heart chamber catheterization. The right heart catheterization (commonly known as Swan-Ganz catheterization) gives the physician the mean pulmonary capillary wedge pressure, which is a reflection of the left atrial pressure. The left heart catheterization, on the other hand, gives the pressure in the left ventricle. By simultaneously taking these pressures, it is possible to determine the gradient between the left atrium and left ventricle during ventricular diastole, which is a marker for the severity of mitral stenosis. This method of evaluating mitral stenosis tends to overestimate the degree of mitral stenosis, however, because of the time lag in the pressure tracings seen on the right-heart catheterization and the slow Y descent seen on the wedge tracings. If a trans-septal puncture is made during right heart catheterization, however, the pressure gradient can accurately quantify the severity of mitral stenosis.

l-TGA can sometimes be diagnosed in utero with an ultrasound after 18 weeks gestation. However, many cases of simple l-TGA are "accidentally" diagnosed in adulthood, during diagnosis or treatment of other conditions.

Tet spells may be treated with beta-blockers such as propranolol, but acute episodes require rapid intervention with morphine or intranasal fentanyl to reduce ventilatory drive, a vasopressor such as phenylephrine, or norepinephrine to increase systemic vascular resistance, and IV fluids for volume expansion.

Oxygen (100%) may be effective in treating spells because it is a potent pulmonary vasodilator and systemic vasoconstrictor. This allows more blood flow to the lungs by decreasing shunting of deoxygenated blood from the right to left ventricle through the VSD. There are also simple procedures such as squatting and the knee chest position which increase systemic vascular resistance and decrease right-to-left shunting of deoxygenated blood into the systemic circulation.

The diagnosis of pulmonary valve stenosis can be achieved via echocardiogram, as well as a variety of other means among them are: ultrasound, in which images of the heart chambers in utero where the tricuspid valve has thickening (or due to Fallot's tetralogy, Noonan's syndrome, and other congenital defects) and in infancy auscultation of the heart can reveal identification of a murmur.

Some other conditions to contemplate (in diagnosis of pulmonic valvular stenosis) are the following:

- Infundibular stenosis

- Supravalvular pulmonary stenosis

- Dysplastic pulmonic valve stenosis

Canadian genetic testing guidelines and recommendations for individuals diagnosed with HCM are as follows:

- The main purpose of genetic testing is for screening family members.

- According to the results, at-risk relatives may be encouraged to undergo extensive testing.

- Genetic testing is not meant for confirming a diagnosis.

- If the diagnosed individual has no relatives that are at risk, then genetic testing is not required.

- Genetic testing is not intended for risk assessment or treatment decisions.

- Evidence only supports clinical testing in predicting the progression and risk of developing complications of HCM.

For individuals "suspected" of having HCM:

- Genetic testing is not recommended for determining other causes of left ventricular hypertrophy (such as "athlete's heart", hypertension, and cardiac amyloidosis).

- HCM may be differentiated from other hypertrophy-causing conditions using clinical history and clinical testing.

d-TGA can sometimes be diagnosed in utero with an ultrasound after 18 weeks gestation. However, if it is not diagnosed in utero, cyanosis of the newborn (blue baby) should immediately indicate that there is a problem with the cardiovascular system. Normally, the lungs are examined first, then the heart is examined if there are no apparent problems with the lungs. These examinations are typically performed using ultrasound, known as an echocardiogram when performed on the heart. Chest x-rays and electrocardiograms (EKG) may also be used in reaching or confirming a diagnosis; however, an x-ray may appear normal immediately following birth. If d-TGA is accompanied by both a VSD and pulmonary stenosis, a systolic murmur will be present.

On the rare occasion (when there is a large VSD with no significant left ventricular outflow tract obstruction), initial symptoms may go unnoticed, resulting in the infant being discharged without treatment in the event of a hospital or birthing center birth, or a delay in bringing the infant for diagnosis in the event of a home birth. On these occasions, a layperson is likely not to recognize symptoms until the infant is experiencing moderate to serious congestive heart failure (CHF) as a result of the heart working harder in a attempt to increase oxygen flow to the body; this overworking of the heart muscle eventually leads to hypertrophy and may result in cardiac arrest if left untreated.

Hypoplastic right heart syndrome is less common than hypoplastic left heart syndrome which occurs in 4 out of every 10,000 births. [3].

This rare anomaly requires prenatal diagnosis since it needs immediate and emergency treatment. Pregnant women whose pregnancy is complicated with this anomaly should be referred to a level 3 hospital with pediatric cardiology and pediatric cardiothoracic surgical team.[3]

It can be associated with aortic stenosis.

For proper diagnosis of situs ambiguous, cardiac and non-cardiac features must be evaluated. Diagnostic criteria for atrial isomerism includes observation of symmetry of thoracic visceral organs upon echocardiogram, arrhythmia upon electrocardiogram, and chest x-ray for confirmation of the heart's location across the left-right axis. In addition, a series of gastrointestinal tests can be conducted for observation of intestinal malrotation, as well as a scan of the liver and spleen for biliary function.

The following table includes the main types of valvular stenosis and regurgitation. Major types of valvular heart disease not included in the table include mitral valve prolapse, rheumatic heart disease and endocarditis.

The prognosis for pulmonary atresia varies for every child, if the condition is left uncorrected it may be fatal, but the prognosis has greatly improved over the years for those with pulmonary atresia. Some factors that affect how well the child does include how well the heart is beating, and the condition of the blood vessels that supply the heart. Most cases of pulmonary atresia can be helped with surgery, if the patient's right ventricle is exceptionally small, many surgeries will be needed in order to help stimulate normal circulation of blood to the heart.If uncorrected, babies with this type of congenital heart disease may only survive for the first few days of life. Many children with pulmonary atresia will go on to lead normal lives, though complications such as endocarditis, stroke and seizures are possible.

Surgical operations to assist with hypoplastic left heart are complex and need to be individualized for each patient. A cardiologist must assess all medical and surgical options on a case-by-case basis.

Currently, infants undergo either the staged reconstructive surgery (Norwood or Sano procedure within a few days of birth, Glenn or "Hemi-Fontan procedure" at 3 to 6 months of age, and the Fontan procedure at 1 1/2 to 5 years of age) or cardiac transplantation. Current expectations are that 70% of those with HLHS will reach adulthood. Many studies show that the higher the volume (number of surgeries performed) at a hospital, the lower the mortality (death) rate. Factors that increase an infant's risk include lower birth weight, additional congenital anomalies, a genetic syndrome or those with a highly restrictive atrial septum.) For patients without these additional risk factors, 5 year survival now approaches 80%. Further, studies show that about 50% of those children who survived surgery in the early development of staged reconstruction have developmental delay or need special education; about 25% of these surgical survivors have severe disabilities. There is growing evidence that while the incidence of developmental and behavioral disabilities continues to be higher than that in the general population, children operated upon in the more current era have shown significantly better neurological outcomes. An alternative to the traditional Norwood is the Hybrid procedure.

Some physicians offer "compassionate care", instead of the surgeries, which results in the child's death, usually within 2 weeks of birth. Compassionate care is overseen by a physician, and may be carried out either in the hospital or at home. However, due to the vast improvement of surgical intervention, with many hospitals achieving over 90% survival, there is debate on whether or not "compassionate care" should still be offered to families. A study in 2003 concluded that a selection of physicians who are experts in the care of children with HLHS were evenly split when asked what they would do if their own children were born with HLHS, with 1/3 stating that they would choose surgery, 1/3 stating that they would choose palliative (compassionate) treatment without surgery, and 1/3 stating that they are uncertain which choice they would make.

The three-stage procedure is a palliative procedure (not a cure), as the child's circulation is made to work with only two of the heart's four chambers.

With a series of operations or even a heart transplant, a newborn can be treated but not be cured. Young individuals who have undergone reconstructive surgery must refer to a cardiologist who is experienced in congenital heart diseases, "Children with HLHS are at an increased level for developing endocarditis." Kids that have been diagnosed with HRHS must limit the physical activity they participate in to their own endurance level.

In terms of treatment for pulmonary valve stenosis, valve replacement or surgical repair (depending upon whether the stenosis is in the valve or vessel) may be indicated. If the valve stenosis is of congenital origin, balloon valvuloplasty is another option, depending on the case.

Valves made from animal or human tissue (are used for valve replacement), in adults metal valves can be used.

Although its cause is poorly understood, situs ambiguous has been linked to family history of malformations and maternal cocaine use, suggesting both genetic and environmental factors play a role. Several genes in the TGF-beta pathway, which controls left-right patterning of viseral organs across the body axis, have been indicated in sporadic and familial cases of atrial isomerism.

There does not appear to be a screening method for prevention of heterotaxy syndrome. However, genetic testing in family members that display atrial isomerism or other cardiac malformations may help to discern risk for additional family members, especially in X-linked causes of heterotaxy syndrome.