AAA ELECTIVE TREATMENT INDICATION TACTICS IN EVAR ERA

All infrarenal abdominal aortic aneurysms (AAAs) should be indicated for elective treatment. Active approach to AAA is based on its fatal prognosis and high difference between sad urgent and acceptable elective repair mortality. In order to provide acceptable results, the risk of the elective repair has to be significantly lower than the risk of AAA rupture . Open surgery (OS) has remained the standard of care in AAA elective treatment. During the last decade, endovascular stentgrafting (EVAR) highly influenced the indications for AAA elective treatment. This miniinvasive and hemodynamically less loading method has extended the elective treatment posibilities of AAA patients who show a high operating risk and are unfit for open surgery. Another AAA treatment possibility, based on primary association of both of the previous methods, is the combined strategy (CS) for AAA of complicated morphology for EVAR (Fig. 1). The type of AAA repair is determined by the patient’s individual operating risk first of all.


INTRODUCTION
All infrarenal abdominal aortic aneurysms (AAAs) should be indicated for elective treatment.Active approach to AAA is based on its fatal prognosis and high difference between sad urgent and acceptable elective repair mortality [1][2][3][4][5][6][7] .In order to provide acceptable results, the risk of the elective repair has to be significantly lower than the risk of AAA rupture 7,8 .Open surgery (OS) has remained the standard of care in AAA elective treatment 9 .During the last decade, endovascular stentgrafting (EVAR) highly influenced the indications for AAA elective treatment [10][11][12] .This miniinvasive and hemodynamically less loading method has extended the elective treatment posibilities of AAA patients who show a high operating risk and are unfit for open surgery [13][14][15] .Another AAA treatment possibility, based on primary association of both of the previous methods, is the combined strategy (CS) for AAA of complicated morphology for EVAR 16 (Fig. 1).The type of AAA repair is determined by the patient's individual operating risk first of all 1 .

RESULTS
Technical success was 100 % in the OS and CS groups.In the EVAR group, primary technical success of 91% was achieved, secondary -assisted-technical success was 98.3 % 1 .There were no severe technical-surgical complications in any of the groups.The rate of cardiac and pulmonary complications was higher in the OS group (n = 14.7 %) versus the EVAR group (n = 7.5 %) (Table 3.).One-month mortality of 4.1 % (n = 10) in all treated groups was related to concomitant diseases.It was 5.2 % (n = 6) in the OS group and 3.1 % (n = 4) in the EVAR group.In the ASA III group it was 14.2 % for OS versus 2.8 % for the EVAR group (Table 4.).In the observed group, 35 % of the patients needed urgent surgery (mortality of 75 %).80 % of low life expectancy untreated patients died of concomitant diseases within six months.

A A B B DISCUSSION
All patients with suspected AAA should be investigated and all patients with proved AAA should be evaluated in terms of repair indication.The basic condition for indicating AAA patiens for elective treatment is their life expectancy and the patient's individual operating risk arising from the particular type of repair 2-4, 7, 8 .The risk of AAA rupture should be higher than the risk of death of concomitant diseases during the time or during the postoperative period 7,8 .Contraindications for elective repair are mostly relative; AAA repair is absolutely contraindicated in patients with life expectancy below one year 8 .At present, classical open surgery (OS), endovas-P.Utíkal, M. Köcher, J. Koutná, P. Bachleda, P. Dráč, M. Černá, E. Buriánková cular repair (EVAR) and combined strategy (CS) are the three possibilities of AAA repair (Fig. 1).Observation does not mean "no treatment".It is waiting for the right timing of repair, when the risk of rupture will be higher than the risk of repair.Elective OS has acceptable morbidity (10-15 %) and mortality (2-8 %) but only in fit patients (ASA II).Hemodynamically loading aortal clamping and invasivity significantly increase the morbidity (40 %) and mortality (19 %) rates in high operating risk patients (ASA III, IV) 6,[13][14][15] .These patients comprise a significant portion of AAA patients.Therefore, the hemodynamically less loading and miniinvasive EVAR, with acceptable mortality also in high operating risk patients (4.7 %), has come into focus in the last decade [12][13][14][15] .Unfortunately, EVAR has technical limitations caused by the present stent-graft system construction and the indication depends on AAA morphology.Not all AAAs could be endovascularly treated [21][22][23] .That is why all questions in preoperative decision as to the type of treatment are connected with the patient risk and AAA morphology.The advantages of both methods are combined and the disadvantages eliminated in CS 16 (Fig. 2).The use of these endovascular techniques (EVAR and CS) seems to be the reason why only 10 % of the patients are rejected from the group of AAA patients with tendency to treat.Low operating risk AAA patients indicated for EVAR were the following: patients after repeated laparotomies, before another severe and complicated surgery of the abdominal cavity, young men with the need of preaortic vegetative plex saving (sexual dysfunction prevention).The best comparision of OS and EVAR mortality and morbidity rates is in the ASA III group of AAA patients and also when we compare OS in ASA II versus EVAR in the ASA III group [13][14][15][24][25][26] . The inceased invasiveness of the combined strategy associated with additional open surgery leads to higher, yet acceptable morbitidy.We have to underline that it is mostly patients of high operating risk that are treated endovascularly.

CONCLUSION
All our results may be successfully compared to the results published by other clinics.
Based on the evaluation of our indication tactics of AAA elective treatment according to one-month results, we can confirm: The endovascular approach is of principal significance for successful AAA elective treatment in high operating risk patients (ASA III, IV).The combined strategy is the method of choice in the morphologicaly complicated AAA repair in these patients.Classical open surgery is recomended in low operating risk patients (ASA II) only.

Table 1 .
Indication of AAA patients for elective treatment

Table 2 .
Indication of AAA patients for elective treatment Type of repair according to patients operating risk

Table 3 .
AAA elective treatment -30 days morbidity -cardiac and pulmonary Surgery in comparision to EVAR according to patients

Table 4 .
AAA elective treatment -30 days mortality Surgery in comparision to EVAR according to patients