ARTERIAL SYSTEM DISEASES

The carotids

The carotids, in combination with the vertebral arteries, are do the job of carrying the blood to the brain and are a possible target for arteriosclerosis and formation of obstructing tissue.
A blocked carotid is particularly dangerous since the obstruction of the artery can cause a stroke. This can happen either directly due to the obstruction itself or when a tiny fragment breaks off and goes to the brain. A stroke is a kind of cerebral seizure (as happens in the heart) whose neurological consequences are sometimes slight, but can also be serious, such as paralysis. When the obstructing tissue causes a severe restriction (stenosis) or when warning signals (e.g. temporary neurological disorders) are felt or when lasting brain damage threatens to get worse, we may decide to perform surgery in order to remove the obstructing tissue itself. Though several types of operation are available using various techniques, we prefer an operation under general anaesthetic using a routine shunt and patch.
To explain these procedures better it is perhaps worth explaining that the operation can be done both under local and general anaesthetic. The choice of local anaesthetic is based mainly on the fact that, throughout the operation, we can monitor the patient from a neurological point of view. A small plastic tube can be inserted which carries (“shunts”) the blood to the brain should the patient not be able to manage the temporary closure of the artery for the time needed to remove the obstructing tissue.

Why is it that in some cases the patient can handle the temporary closure of the artery and in others not?

Because the arteries on either side join each other in the brain. If one is temporarily closed, the other can replace its, working as a substitute. However, this does not always happen, and that’s not all. We don’t have perfect methods of knowing if and when the substitution will not work. What’s more, failure to substitute can occur during the operation itself.
In order to deal with all eventualities we insert the shunt as a matter of routine in all cases. This guarantees that the brain will always receive the blood flow. This also means that a local anaesthetic is not necessary. A general anaesthetic makes things much easier for the surgeon and more comfortable for the patient. The operation can thus be carried out slowly and with meticulous attention to detail, and this helps us to achieve a technically perfect performance.
The obstructing tissue can also reform and to prevent this happening it is advisable, when we close the artery, to widen it by adding tissue. We do this by means of a “patch”. The routine application of a patch drastically reduces the chances of further restriction of the artery but requires more time: another reason why we prefer a general anaesthetic.
Any operation on the carotids requires careful assessment of all districts and especially the coronary arteries, since these are often affected by the pathology. In particular cases we perform a so-called “combined operation” where, during the same intervention, a coronary by-pass is performed as well as an operation on the carotids.
When the intervention on the carotids is performed in isolation, the patient has a brief stay in hospital and makes a swift recovery.
Apart from being removed, the obstructive tissue can also be squashed inside the artery. This is done by inserting a probe, which places a spring made of a special material to a predefined site. Once in position, this spring dilates and squashes the obstructing tissue against the wall of the blood vessel.
Since there is a risk of fragments detaching and being carried to the brain, we first position a special filter designed to prevent this happening. The filter is removed at the end of the procedure.
Some obstructive tissue can be treated in this way, while other tissue requires surgical treatment. A pre-op assessment taken together with the general conditions of the patient are what help us decide which method to adopt.
Extremely careful assessment, the routine use of the shunt and microsurgical techniques have enabled us to achieve a percentage of complications that is much lower than the universally accepted optimum. Of particular significance is the fact that neurological complications after the patient wakes up are equal to 0%.

Dopo aver inserito lo shunt per consentire l'afflusso di sangue al cervello, si inizia ad asportare la placca carotidea	L'asportazione della placca viene completata
La carotide viene accuratamente pulita	Inizia la ricostruzione utilizzando un patch di materiale biologico
La ricostruzione è completata	La derivazione del sangue viene rimossa ed il flusso diretto ristabilito