| From your Guide Dr.MANI |  | |
Single Ventricle | ||
| From your Guide Dr.MANI | | |
Single Ventricle | ||
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Intermediate Operations
VSD enlargement
Sometimes surgery may be necessary in between palliative and definitive procedures to treat complications that arise in the interim.
Bidirectional Glenn Shunt
In some cases of single ventricle, especially after PA banding, obstruction may develop in the sub-aortic region. Usually this is due to narrowing of a pre-existing VSD. Surgery may be required to enlarge this VSD be excising its margins.
This shunt has also been discussed in the article on Fontan Operation for Tricuspid Atresia. In cases where patients are not yet suitable for Fontan operation (due to presence of risk factors like sub-aortic stenosis, high lung blood vessel resistance, distortion of pulmonary artery branches) but symptom status worsens, a Glenn shunt may be done on one or both sides, followed by a completion Fontan operation at a later date.
Definitive Repair for Single Ventricle
There are two kinds of repair procedures for Single Ventricle - Ventricular Septation and Fontan procedure.
Ventricular Septation
In this operation, an attempt is made to re-create an artificial partition in the large ventricular chamber so that blood from the left and right atria will be separated inside the ventricle. The operation requires many pre-conditions, and is not suitable for a large percentage of patients.
What are the conditions for ventricular septation to be possible ?
How is the ventricular septation operation carried out ?
What are the risks of septation ?
How do patients do after septation ?
Fontan Operation
Heart Transplantation
If all the above conditions are met, a septation operation can be performed. This is an open heart operation performed with the patient hooked up to the heart-lung machine. With the heart beat stopped, the surgeon opens the right atrium and evaluates the ventricle through the tricuspid valve. After choosing the level of partition, multiple sutures are passed into the ventricle wall. These sutures are then threaded into a suitably shaped patch made of Dacron fabric backed with pericardium to make it less porous and reduce the risk of clot formation on the patch. The sutures are tied down, securing the patch in place.
Now pure blood from the left atrium will cross the mitral valve to the left side of the ventricle and leave through the aortic valve. Impure venous blood from the right atrium will pass across the tricuspid valve into the right side of the ventricle and into the pulmonary valve.
Ventricular septation is a major operation with a rather high mortality rate of 30% to 40%. One major complication of this operation is damage to the conduction system of the heart causing heart block. As a routine, pacemaker leads are inserted at the time of surgery, and many patients require insertion of a pacemaker later.
The limited number of patients followed up late after septation makes this a difficult question to answer reliably. Of those patients evaluated subjectively, exercise tolerance and life style were near normal. Objective studies however demonstrated ventricular function to be inferior compared to patients who had a Fontan operation. Late re-operation for AV valve regurgitation has been required for some patients.
The Fontan operation has been discussed in great detail in the section on Tricuspid Atresia.
The role of paediatric heart transplantation is still being evaluated, and the same arguments as in cases of HLHS apply here.
If there's anything more you want to read about, or some areas which aren't clear enough, don't
hesitate to write and let me know.
Copyright 1998, All rights reserved.
