Echocardiogram
Congenital heart defects are now diagnosed with echocardiography, which is quick, involves no radiation, is very specific, and can be done prenatally.Echocardiography establishes the presence of TOF by demonstrating a VSD, RVH, and aortic override. Many patients are diagnosed prenatally. Color Doppler (type of echocardiography) measures the degree of pulmonary stenosis. Additionally, close monitoring of the ductus arteriosus is done in the neonatal period to ensure that there is adequate blood flow through the pulmonary valve. : 171–72 In certain cases, coronary artery anatomy cannot be clearly viewed using echocardiogram. In this case, cardiac catheterization can be done. : 37, 201

Genetics
From a genetics perspective, it is important to screen for DiGeorge in all babies with TOF. : 37, 201

Treatment
Tet spells
Tet spells are defined as cyanotic spells occurring due to the obstruction right ventricular outflow. Tet spells can be triggered by various factors such as crying, progressive tachypnea, and deep breathing, with symptoms including but not limited to blue skin, nails and lips, profound crying and difficulty breathing.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. : 18, 201 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.
Cause
While the specific causes of TOF have not been fully identified, there are various environmental or genetic factors that have been associated with TOF. So far, around 20% of overall CHD cases have been due to known causes such as genetic defects and teratogens which are various factors causing embryo development abnormalities or birth defects. However, the other 80% of cases have little known about their cause.Genetic factors linked to TOF include various gene mutations or deletions. Gene deletions associated with TOF include chromosome 22 deletion as well as DiGeorge syndrome.Specific genes associations with TOF include:

JAG1 codes for ligands within the Notch family of proteins and is highly expressed in the developing heart. Mutations of the JAG1 gene can lead to abnormal heart development associated with TOF. NKX2-5 codes for cardiac morphogenesis regulators to allow for proper heart development. Defects in this gene typically causes septal defects and has been associated with around 4% of all TOF cases. ZFPM2 is another cardiac regulator involved in regulation of GATA4. Mutations of the ZFPM2 gene lead to reduced GATA production and have been seen in some TOF cases. VEGF a well-known endothelial growth factor involved in the vascularization of the heart. Decreased VEGF expression has been shown to be a modifier of TOF. NOTCH1 is involved in the vascularization of tissues and is the most common site of genetic variations involved with TOF, accounting for 7% of all TOF cases. TBX1 expresses progenitors involved with the development of the right ventricle.