1.) what is an aneurysm?
It is a segmentary arterial dilation due to degenerative changes of the arterial wall. Hypertension is very much responsable for these changes.
2.) What is it an aortic aneurysm?
The aorta is the largest artery, coming out of the Heart and distributing blood througout the body.When the dilation of the aorta is placed between the subclavian and the renal arteries it is named “Thoracic aneurysm”.Below the renal arteries it is an abdominal aneurysm (AAA).Their incidence is 20% for the thoracic aneurysm and 80% for the abdominal aneurysm.
3.) Who can suffer from an aortic aneurysm?
Risk factors to develop an aortic aneurysm are:
- Familiar history
- Arterial Hypertension
- Lipid disorders(high colesterol levels)
- Males over 50(women can also suffer from aneurysms in a lower proportion -6/1-)
4.) What are the symptoms?
They are generally asymptomatic. One come across them, mostly when performing complementary studies demanded for a physician for other reasons. CT scan, angiografies, Magnetic Resonance might be a way of discovering the aneurysm characteristics
It becomes symptomatic when, because of its growth, it involves other structures and thoracic or abdominal tenderness begins to feel.
5.) Is it difficult to diagnose an aortic aneurysm?
Echography, CT Scan or angiotomography can be a way for an early diagnose of thoracic or abdominal aneurysms.These are non invasive studies, sure and with no collateral effects.
6.) What happens with the untreated aneurysms?
The natural history of an aneurysm is growing as time goes by. Sometimes some of them break, putting the patients life at risk.
Statistics show that 50% of all broken aneurysms lead to death before arriving at hospital. Among the ones who manage to arrive alive to the hospital, 50% die before entering the O.R. And among those which are treated in the emergency O.R 50% cannot survive the surgical procedure.So, a teared aneurysm has between 10% and 50% chance to succeed in surgery. Nevertheless, if treated electively before this instance, survival is 94-97%.
7.) What can be done with a patient carrying an aortic aneurysm?
It depends on the anuerysm size. One with less than 50mm diameter needs to be controlled annually with CTScans. After reaching 50 mm diameter, it must be treated.
8.) How to treat an aortic aneurysm?
Presently standard procedure is conventional surgery “open procedure”.The segment of dilated artery is replaced by an adecquate graft. Due to the high stress the patient undergoes considering general anesthesia, when co-morbid situations are present (cardiac or respiratory deseases) surgical risk is considerably higher.
An alternative treatment is to implant an endovascular graft. By means of this technique, an internal by-pass is made allowing the blood flow inside this graft, preventing the anuerysm from being pressurized and broken.This new technique consists in placing the endograft through small approaches in the groins. It is implanted throughout one or both femoral arteries and placed in the appropriate site to exclude the aneurysm from blood circulation.
9.) What is the situation if along with the aortic aneurysm there is also cardiac insufficiency, or pulmonary chronic obstructive desease or both?
Ten years before, patients under these conditions could not undergo surgery. It was usual to wait until rupture occurred.
In the present time it is possible for these patients to repair their aneurysms through the endovascular way. The groin approach of the femoral arteries using local or epidural anesthesia allows the implant of an endovascular graft with a very low risk. Thus an accurate repair of the deffect is quickly achieved .
10.) How many kinds of endografts are aveilable in the market?
There are many endoprostheses in market of two kinds: selfexpandable and balloonexpandable grafts.
Selfexpandable grafts have been approved by the sanitary authorities in USA (FDA) and European Ecconomical Community (CE) to be implanted under very strict controls. There are very well defined anatomical parameters to observe: the neck (distance between the renal arteries and the beginning of the aneurysm) it must be more than 15 mm long; the angle between the aneurysm and the neck must be less than 60 degrees, and the iliac arteries anatomy must be compatible with the devices, not angled or severely stenotic.
The employment of autoexpandable endografts without considering these limitations is an ilegal action because it considerably increases their rate of failures.
Nontheless, international ramndomized studies reveal a high rate of failures of the selfexpandable endografts, even when implanted following this strict specifications.
Different scientific papers blame the selfexpandable endoprostheses failures to its selfexpandable nature.
On the other hand the balloon expandable endoprostheses SETA, developed in LATECBA S.A. do not have anatomical limitations to treat abdominal aortic aneurysms (lenght of the necks, angles, calcium, partial occlusions or kinkings in aorta or iliac arteries).