AORTIC ANEURYSMS

In the West of Ireland we have seen a paradigm shift in the management of patients with Abdominal Aortic Aneurysms.  The main impetus for this change has been vascular specialisation and the concomitant introduction of Endovascular techniques.

ADDITIONAL SERVICES

Specialist vascular service with high deliberate practice volumes

Since the foundation of the Western Vascular Institute and the provision of Specialist Services into Galway University Hospital, we have experienced a dramatic rise in the volume of patients treated with AAA1. Before 2001 all AAA repairs were done by open repair. Since 2001, the total volume of AA repairs has increased by 65%. However the additional case-load has been managed by EVAR with a high-turnover rate. The absolute number of open repairs has not increased. (Mean no of open AAA repairs before 2001= 17 vs Mean no. of open AAA repairs from 2001 onwards =28, p=0.140). (Figure 1)

Figure 1 : Total Volume of Elective AAA repairs in GUH (1995-2007)

A specialised high deliberate practice volume has led to marked improvements in outcomes with open repair.

Pre-2001 Post-2001 P Hazards Ratio 95%CI
Elective 15.7% 1.8% <0.0001* 0.12 0.05 – 0.30
Emergency 64.3% 34.4% 0.0172* 0.45 0.26 – 0.79

Table 1 : Peri-operative Mortality for AAA Repair pre- and post- 2001

Theses rates compare very favourably to international standards.

U.S.A. U.K. WVI
Elective Repair 1.4% <5% <1.8%
Emergency Repair 37.3% 46% 34.4%

Table 2 : Recommended Mortality Rates for AAA Repair1

15 MINUTES THAT COULD SAVE YOUR LIFE

More About Screening

HIGH RISK PATIENTS

In a study published in Vascular in 20051, we found that age in itself does not preclude intervention in patients over 80 years of age. Survival for Octogenarians at 5 years was similar to their younger counterparts for elective and open repair (Figure 1)

Figure 1 (a) : 5-year survival rates for AAA patients

Figure 1 (b) : 5 year elective survival rates were similar for Infrarenal (86.1%) vs. Pararenal (72%). p=0.403, h=0.61 [95%CI=0.18-2.02]

High risk patient analysis

Regardless of Age both groups fared significantly better at five years with elective repair compared to emergency repair (p=0.0024) or non-operative management (p=0.0041). Rupture rate is closely correlated with expansion rate, P2.

This study, in line with previous work at the WVI2,3, has shown that screening is vital to enhance overall survival from AAA. Patient Selection for Elective repair needs to be stringent. However, age alone, should not influence choice of management and screening should reduce the incidence of octogenarian rupture while at the same time identifying those most suitable for non-operative management.

 References

  1. Hynes N, Sultan S. Abdominal aortic aneurysm repair in octogenarians versus younger patients in a tertiary referral center.
    Vascular 2005 Sep-Oct; 13(5):275-85. PMID: 16288702
  2. Sultan S, Hynes N. Survival of ruptured abdominal aortic aneurysms in the west of Ireland: do prognostic indicators of outcome exist?
    Vasc Endovascular Surg. 2004 Jan-Feb; 38(1):43-9. PMID: 14760476
  3. Sultan S, Hynes N. Endovascular repair of early rupture of Dacron aortic graft–two case reports.
    Vasc Endovascular Surg. 2005 Mar-Apr;39(2):183-90. PMID: 15806280

SCREENING

AAA rupture is a fatal event but with peri-operative mortality rates of less than 1.8%, at the WVI, regardless of age, elective repair is a life-saving and cost-effective treatment.

But aneurysms have to be detected before rupture in both men and women. Similar to the rest of the modern world, cardiovascular disease is the leading killer in Ireland. Vascular deaths in Ireland far exceed those from all forms of cancer combined. To help in the fight against cardiovascular morbidity and mortality, we have established a free vascular screening program in the vascular laboratory, pioneering combined testing for overall cardiovascular disease.

The screening program provides quick, accurate and minimally invasive testing for abdominal aortic aneurysms and leading causes of stroke.

As a marker of peripheral arterial disease and cardiovascular burden we also include Ankle Brachial Indices in the 15min routine.To date we have screened more than 1,500 patients with a 25% pick-up rate.