Ventricular Septal Defect
Exams and Tests continued...
A ventricular septal defect is detected on physical examination by a systolic murmur audible with a stethoscope along the lower left sternal or breast bone border. It is related to the oxygenated blood “swishing” through the hole or VSD into the right ventricle.
The presence of a hole in the heart can be confirmed by echocardiogram. This painless test uses ultrasound waves to construct a moving picture of the heart. It can quantitate the size of the left-to-right shunt by enlargement of the left ventricle, pressure in the lungs, and actually estimate the degree of shunting by an empirical formula.
Chest x-ray is useful to see if the overall heart size is enlarged, plus evidence of fluid in the lungs or pulmonary congestion. An electrocardiogram is helpful in checking to see if the left ventricle is the dominant working muscle, ie the more of right ventricular enlargement or hypertrophy seen, the more the physician must worry about pulmonary hypertension, and therefore operate sooner.
Cardiac catheterization may be performed in certain circumstances.
- In this procedure, a very thin plastic tube called a catheter is inserted into the skin in the groin, arm, or neck (under local anesthesia with minimal pain) and advanced to the heart under x-ray observation by the cardiologist.
- Pressures are measured inside the heart, especially if any concern was previously raised over the degree of pulmonary hypertension and therefore operability. If the lung pressures are very high and won’t drop with oxygen and additional vasodilating drugs, the patient may not be operable.
- If additional abnormalities are possible, a dye study may be performed to visualize the anatomy of inside the heart. But the echocardiogram accomplished this goal in the majority of patients, ie most patients don’t need a cardiac catheterization for a routine VSD.
Ventricular Septal Defect Treatment
In some children with ventricular septal defect, the defect will close on its own as the child grows.
If a larger ventricular septal defect is causing symptoms, your child's health care provider may prescribe medication.
- Which medication is prescribed depends on the severity of symptoms.
- The goal of therapy is to reduce the symptoms of congestive heart failure, such as poor growth and development, weight loss and/or poor weight gain, excessive sweating, and fast breathing. An older patient typically develops fluid in the lungs, liver, and legs.
- If serious infections and/or dental work is needed, antibiotics are needed to prevent the infection from spreading to the VSD, ie infectious endocarditis, which is potentially fatal.
- Vasodilators: Angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers are used to decrease the work load on the left ventricle.
Digoxin (Lanoxin) increases the strength of the heart muscle to deal with the greater blood volume.
- Diuretics such as Lasix (furosemide) or spironolactone help remove excess fluid from the body so the heart doesn't have to work as hard and the patient feels much better.