This echocardiogram in the subcostal 4-chamber view shows the ventricular septum extending from nearly the apex of the heart to the level of the atrioventricular valve. Note the large gap approximately in the middle of the septum. this gap identifies a large mid muscular defect. In the real-time color flow Doppler study that follows, note the uniform color of flow across the defect, indicating the absence of turbulence. This reflects equalization of pressures in the two ventricles due to the large size of the defect.
Pulmonary arterial vasodilation
Pulmonary arterial vasodilation would increase the proportion of left ventricular outflow crossing a large ventricular septal defect, thereby, increasing pulmonary blood flow and accentuating the problems created by a large defect.
Symptomatic treatment
Symptomatic treatment of an infant with congestive heart failure due to a large ventricular septal defect may include the following: Digoxin, improves myocardial performance by increasing contractility for a given energy demand. Diuretics reduce circulating blood volume by increasing renal excretion of salt and water, this improves pulmonary function and decreases systemic venous pressure. Systemic arterial vasodilators improve systemic cardiac output and tend to reduce the percentage of left ventricular output that crosses the ventricular septal defect. Many infants with a large ventricular septal defect grow poorly, because they fatigue rapidly during nursing, this prevents ingestion of sufficient calories per day, particularly in the face of increased energy demand created by the effects of the defect. Increased caloric concentration formula provides the infant with more calories for the amount of fluid ingested, with less time needed for feeding.
Medical therapy
Defects causing heart failure can demonstrate prompt and effective response to medical therapy. In such patients, spontaneous reduction in size and even eventual closure may follow. If there is no rapid and substantial response to medical therapy, however, intervention to close the defect is warranted, as it is important not to allow growth failure to persist. Most large ventricular septal defects causing congestive heart failure are treated best by closure of the defect, either by surgery or by placing an occluding device at cardiac catheterization.
TEE - device closure in place
These transesophageal echocardiographic images illustrate placement of a transcatheter umbrella closure device in a large muscular ventricular septal defect. In the frame on the left, the device is outlined, indicating the large arm of the device on the left ventricular side of the septum and the smaller component on the right ventricular side. The real-time study that follows illustrates almost total closure of the defect. Note that the device mechanism lying within the defect itself is not clearly seen. A tiny color signal can be seen crossing the central portion of the device. This minimal residual shunt will close within a few weeks.