Audit of Endoluminal Repair of Abdominal Aortic Aneurysms

Audit of Endoluminal Repair of Abdominal Aortic Aneurysms – Long term follow upFinal Report to Cook Australia Prepared March 2009 Australian Safety a...
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Audit of Endoluminal Repair of Abdominal Aortic Aneurysms

– Long term follow upFinal Report to Cook Australia Prepared March 2009 Australian Safety and Efficacy Register of New Interventional Procedures – Surgical The Royal Australasian College of Surgeons

ASERNIP S

Audit of Endoluminal Repair of Abdominal Aortic Aneurysms Final report on Zenith graft patients Prepared for Cook Australia March 2009

Address: 1st Floor, 38 Payneham Road, Stepney 5069 Postal: PO Box 533 Stepney, SA 5069, Australia Phone: (08) 8363-7513 Fax: (08) 8362-2077 Email: [email protected] Web: http://www.surgeons.org/asernip-s

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Table of Contents Table of Contents ...........................................................................................................3 List of Tables .................................................................................................................4 Appendices.....................................................................................................................4 Introduction ....................................................................................................................5 IItteem m 3333111166 .................................................................................................................5 IItteem m 3333111199 .................................................................................................................5 Audit Overview..............................................................................................................6 CCoonnffiiddeennttiiaalliittyy aanndd pprriivvaaccyy........................................................................................6 D Daattaa ccoolllleeccttiioonn ...........................................................................................................7 PPaarrttiicciippaattiinngg ssuurrggeeoonnss ................................................................................................7 D Daattaa iinnppuutt ...................................................................................................................7 D Daattaa rreecceeiivveedd .............................................................................................................7 N Naattiioonnaall D Deeaatthh IInnddeexx .................................................................................................8 RReeppoorrttaaggee ...................................................................................................................8 A Accccrreeddiittaattiioonn ooff tthhee A ASSEERRN NIIPP--SS aauuddiitt .....................................................................8 CCoonnffeerreennccee pprreesseennttaattiioonnss ...........................................................................................9 PPuubblliiccaattiioonnss ..............................................................................................................10 Results of Zenith Graft Patients ...................................................................................12 PPrree--ooppeerraattiivvee ppaattiieenntt ddeem mooggrraapphhiiccss .........................................................................12 3300--ddaayy tteecchhnniiccaall ssuucccceessss ..........................................................................................13 M Moorrttaalliittyy ..................................................................................................................13 PPeerriiooppeerraattiivvee m moorrttaalliittyy.............................................................................................13 M i d t e r m a n d mm moorrttaalliittyy ...........................................................................14 Mid-term and lloonngg--tteerrm A m--rreellaatteedd m moorrttaalliittyy aanndd rruuppttuurree ..................................................................15 Anneeuurryyssm RRuuppttuurree.....................................................................................................................16 EEnnddoolleeaakkss aanndd ootthheerr ccoom mpplliiccaattiioonnss .........................................................................17 A d d i t i o n a l P r o c e d u r e s a Oppeenn RReeppaaiirr ..........................................18 Additional Procedures anndd CCoonnvveerrssiioonn ttoo O Discussion ....................................................................................................................21 CCoonncclluussiioonnss ..............................................................................................................23 References ....................................................................................................................24 Appendices...................................................................................................................25

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List of Tables Table 1. Pre-operative ASA in patients treated with Zenith graft* .............................12 Table 2. Enrolments, follow-up and mortality............................................................13 Table 3. Cause of early mortality and days to death....................................................14 Table 4. Cumulative mid to long term mortality .........................................................14 Table 5. Cause of mid to long term mortality in Zenith patients1................................15 Table 6. Zenith Graft Patient Experiencing Aneurysm Rupture..................................16 Table 7. Endoleaks recorded < 30 days (n=21) ...........................................................17 Table 8. Mid to long term follow-up visits where endoleak and other complications were reported ...............................................................................................................18 Table 9. Zenith graft patients converted to open repair early (30 days postoperative) conversion to open repair ....19 Table 11. Time to additional open and endovascular procedures in mid to long term 20

Appendices EVAR Audit Data Entry Paper Forms………………………………………………..24 Categorisation of cause of mid-long term mortality……………………………………25

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Introduction In May 1999 the Medical (formerly Medicare) Services Advisory Committee (MSAC) assessed and reported on the procedure of endovascular aneurysm repair (EVAR). Their results showed that although the procedure appeared effective in the short-term, there was insufficient evidence concerning the long-term safety and efficacy.1 The procedure involves the elective repair of abdominal aortic aneurysms (AAA) using an endovascular graft. The graft is inserted through an incision in the femoral artery and positioned within the aorta at the site of wall weakening (the aneurysm) in order to prevent rupture. As a consequence, the Australian Government Department of Health and Ageing commissioned the Australian Safety and Efficacy Register of New Interventional Procedures – Surgical (ASERNIP-S) to manage a national collection of data for the evaluation of endovascular aneurysm repair (EVAR). ASERNIP-S is part of the Research, Audit and Academic Surgery Division of the Royal Australasian College of Surgeons (the College) and the project is managed from the office in Adelaide, South Australia. As a result of consideration of the audit’s final progress report to the Government showing the five-year outcomes of patients treated by EVAR, the Minister for Health and Ageing, the Hon. Tony Abbott endorsed MSAC’s recommendation of permanent funding for two item numbers allocated to the procedure on the Medical Benefits Schedule: IItteem m 3333111166: Infrarenal abdominal aortic aneurysm, replacement by tube graft using endovascular repair procedure, excluding associated radiological services (Ministerial Determination) (Anaes.) (Assist.) IItteem m 3333111199: Infrarenal abdominal aortic aneurysm, replacement by bifurcation graft to one or both iliac arteries using endovascular repair procedure, excluding associated radiological services (Ministerial Determination) (Anaes.) (Assist.) In 2006, Cook Australia agreed to fund the audit to continue follow-up data collection for a further two years. This report presents the results obtained for information submitted on patients who had a Zenith graft repair for abdominal aortic aneurysm between 1 November 1999 and 16 May 2001. This information is a subset (82%) of that submitted to the audit of endoluminal (endovascular) repair of abdominal aortic aneurysms. This report represents the mid to long term outcomes of patients undergoing endovascular repair of abdominal aortic aneurysms using the Zenith graft. Vascular surgeons throughout Australia registered a total of 787 patients in the Zenith data subset.

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Audit Overview The Australian Safety and Efficacy Register of New Interventional Procedures – Surgical (ASERNIP-S), has established and managed the audit. A project officer is responsible for managing the audit, with supervision from the ASERNIP-S’ Morbidity Audit Manager, the Director of the Research, Audit and Academic Surgery Division of the College and ASERNIP-S Surgical Director, Professor Guy Maddern. An independent reference group of senior vascular surgeons with a high level of expertise in the procedure provided advice on clinical aspects of the audit. The group comprises the following members: • Professor Guy Maddern (Chair) (Adelaide, South Australia) • Mr John Anderson (Adelaide, South Australia) • Mr Michael Denton (Melbourne, Victoria) • Associate Professor Robert Fitridge (Adelaide, South Australia) • Professor John Harris (Sydney, New South Wales) • Mr Michael Lawrence-Brown* (Perth, Western Australia) • Professor James May (Sydney, New South Wales) • Professor Kenneth Myers (Melbourne, Victoria) * Mr Lawrence-Brown has recently retired and has subsequently resigned from this group.

C Coonnffiiddeennttiiaalliittyy aanndd pprriivvaaccyy The audit contains sensitive health information. Advice was sought regarding its handling and housing to ensure that the information was handled appropriately. In 2000, amendments were made to the Privacy Act 1988 (Cwth): The Privacy Amendment (Private Sector) Act 2000 (Cwth), which came into effect 21 December 2001. In order to ensure that the rights of patients were respected by ASERNIP-S, guidance was obtained from the College Ethics Committee, and the lawyer acting for the College. Recommendations were made that ASERNIP-S provide information for patients about the audit and that patients provide consent for the release of their health information. As a result of these recommendations information brochures and consent forms were provided to surgeons to use at patient follow-up. The patient information brochure, patient consent forms and a privacy statement (which includes information about the EVAR audit) are available for download from the ASERNIP-S web site: http://www.surgeons.org/Content/NavigationMenu/Research/ASERNIPS/ ASERNIPSAudits/Audits.htm

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The EVAR audit has been declared a quality assurance activity by the Minister for Health and Ageing, the Hon. Tony Abbott under Part VC of the Health Insurance Act 1973 (QAA No. 2/2004). D Daattaa ccoolllleeccttiioonn This section describes the methods used to facilitate accurate and complete data collection. PPaarrttiicciippaattiinngg ssuurrggeeoonnss During the period of initial data collection around 80 surgeons were performing the EVAR procedure and have continued to submit their data. D Daattaa iinnppuutt Most data have been submitted using paper-based forms (Appendix 1). Other methods, such as encrypted internet submission or Access databases, were provided earlier in the audit period but were not widely used. The information was entered into a password-protected Access 2003 database. Most of the data was double-checked to ensure data integrity. The date of data entry and checking was logged. Surgeons were asked to provide information using three separate forms: • Operative form – information obtained in the period immediately prior to and during the procedure • Discharge form – including information obtained postoperatively, up to 30 days from the time of the procedure • Follow-up form – aimed to collect information at regular follow-up intervals of 3 months, 6 months, 12 months and then on an annual basis. Copies of each form are included in Appendix 1. The forms do not include any universal identifiers such as the Medicare or Veterans Affairs Numbers as stipulated by the Privacy Amendment (Private Sector) Act 2000, in National Privacy Principle 7.1. Changes were made to the forms in 2004 to identify Type III and Type IV endoleaks. D Daattaa rreecceeiivveedd ASERNIP-S was required to collect procedures performed privately in Australia between November 1999 and May 2001. An estimate of the number of private procedures performed was obtained from the Health Insurance Commission (HIC), and a comparison with ASERNIP-S data indicates that around 90% of these cases were submitted.

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A proportion of patients are considered lost to follow-up by surgeons. Advanced age and/or increasing frailty of patients may have necessitated their movement to nursing home care; the patient may move to be closer to family members and becomes lost to follow-up. Additionally, with advancing age and frailty some of these patients are lost to follow-up when they refuse further monitoring. A number of patients were also lost when, for instance, their surgeon retired and we have not been able to establish the new surgeon or GP responsible for these patients. In summary, the barriers to follow-up include worsening health, distance, cost and movement between service providers. N Naattiioonnaall D Deeaatthh IInnddeexx The National Death Index (NDI) is a database which lists all deaths that have occurred in Australia since 1980. It is maintained by the Australian Institute of Health and Welfare (AIHW) in Canberra. An application to use the database to track patients enrolled in the audit was first made in 2004. The project received clearance from the AIHW Ethics Committee, which has continued to monitor the project every 12 months. The last application to use NDI data was made in July 2008. Frequently, patients who have been listed as lost to follow-up were subsequently identified through the NDI. R Reeppoorrttaaggee Surgeons participating in the audit received an updated list of their audit information every three months. This ensured that surgeons remained informed if follow-up information was due. The progress of the audit was reported at each ASERNIP-S Management Committee meeting. An update of audit activities has been provided to the Council of the College monthly. During the initial funding period for the audit, reports were submitted to the Australian Government Department of Health and Ageing at six-monthly intervals. For the final phase of the audit’s initial funding (November 2005 – October 2006) a report was submitted in February 2006 and the final report was submitted in October 2006. A Accccrreeddiittaattiioonn ooff tthhee A ASSEER RN NIIPP--SS aauuddiitt The College Board of Professional Development and Standards approved the EVAR audit for the purposes of their Continuing Professional Development Program. The audit has been listed on the College website under approved audit activities: http://www.surgeons.org/Content/NavigationMenu/FellowshipandStandards/Professi onalStandards/FAQS/surgical_audit_peer_review_2005.pdf Publications and presentations related to the audit are shown below:

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C Coonnffeerreennccee pprreesseennttaattiioonnss 2007 •

Boult M - on behalf of the RACS Research & Audit Division. Pilot Audit of peripheral stenting procedures. Vascular Interventions 2007. Newcastle, NSW Australia. February 2007.



Boult M, Fitridge R, Barnes M, Maddern G. Using audit data to develop a predictive model of success for endovascular repair of abdominal aortic aneurysms. 5th Australsian Conference on Safety and Quality in Health Care. Brisbane, QLD Australia. August 2007.



Fitridge, Boult, Barnes, Maddern. Mid term results of EVAR based on asernip-s audit. Vascular 2007. Melbourne, VIC Australia. August 2007.

2006 •

Golledge J, Parr A, Boult M, Maddern G, Fitridge R. The outcome of endovascular repair of small abdominal aortic aneurysms. “Vascular 2006”. The Australian and New Zealand Society for Vascular Surgery. Cairns, QLD Australia. September 2006.



Fitridge R, Boult M, Babidge W, Maddern G on behalf of the ASERNIP-S EVAR reference group. Effect of pre-operative variables on the mid-term outcomes for patients treated in Australia for endovascular repair. Annual Scientific Congress of the Royal Australasian College of Surgeons. Sydney, NSW Australia. May 2006.

2005 •

Fitridge R, Boult M, Babidge W, Maddern G. ASERNIP-S audit of endoluminal repair of abdominal aortic aneurysms in Australia. Annual Scientific Congress of the Royal Australasian College of Surgeons. Perth, WA Australia. May 2005.

2004 •

Fitridge R, Boult M, Babidge W, Maddern G. Endoluminal repair of abdominal aortic aneurysms – contemporary Australian experience. Annual Scientific Congress of the Royal Australasian College of Surgeons. Melbourne, VIC Australia. May 2004.



Fitridge R, Boult M, Babidge W, Maddern G. Endoluminal repair of abdominal aortic aneurysms – Australian audit. ISCVS World Congress, Hawaii USA. April 2004.

2003

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Fitridge R, Boult M, Babidge W, Maddern G (for the ASERNIP-S Reference Group for endoluminal graft repair). The Australian Audit of the Safety and Efficacy of Endoluminal Grafts for the Repair of Abdominal Aortic Aneurysms. Annual Scientific Congress of the Royal Australasian College of Surgeons. Brisbane, QLD Australia. May 2003.

2002 •

Harris J. Australian audit of endoluminal and open repair of abdominal aortic aneurysms. 15th Annual International Congress for Endovascular Interventions. Phoenix, Arizona USA. February 2002.



Fitridge R. ASERNIP-S follow-up data. Annual Scientific Congress of the Royal Australasian College of Surgeons. Adelaide, SA Australia. May 2002.



Boult M, Babidge W, Coburn D, Maddern G. Data collection on a new technology to inform funding decision making by the Australian Government. (Poster). 18th Annual Meeting for the International Society of Technology Assessment in Health Care (ISTAHC). Berlin, Germany, June 9-12, 2002.



Boult M, Babidge W, Maddern G. The role of audit in improving health outcomes. Australasian Health Research Data Managers Association, Brisbane, Australia, 21-22nd August 2002.M Denton, R Fitridge, M Boult, W Babidge & G Maddern (for the Endoluminal Reference Group). Highlights from the ASERNIP-S Registry; What are the important findings for clinical practice? International Endovascular Symposium. Sydney, NSW Australia, December 5-7, 2002.

2001 •

Maddern G and Fitridge R. Annual Scientific Congress of the Royal Australasian College of Surgeons. Canberra, ACT Australia. May 2001.



Boult M, Ethics and the Law - Some Issues involved in Data Collection, Australasian Health Research Data Managers Association, Melbourne, VIC Australia, 13-14th September 2001.

PPuubblliiccaattiioonnss 2006 •

Golledge J, Parr A, Boult M, Maddern G, Fitridge R. The outcome of endovascular repair of small abdominal aortic aneurysms. Annals of Surgery. 2007; 245(2): 326-333.

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Boult M, Babidge W, Maddern G, Barnes M, Fitridge R. Predictors of success following endovascular aneurysm repair: mid-term results European Journal of Vascular and Endovascular Surgery 2006; 31(2):123-129.

2004 •

Boult M, Babidge W, Maddern G, Fitridge R, on behalf of the Reference Group. Endoluminal repair of abdominal aortic aneurysm – contemporary Australian experience. European Journal of Vascular and Endovascular Surgery. 2004; 28(1): 36-40.

2002 •

Boult M, Babidge W, Anderson J, Denton M, Fitridge R, Harris J, LawrenceBrown M, May J, Myers K, Maddern G. Australian audit for the endoluminal repair of abdominal aortic aneurysm - the first 12-months. Australian and New Zealand Journal of Surgery. 2002; 72(3):190-195.



Boult M, Babidge W, Roder D, Maddern G. Issues of consent and privacy affecting the functioning of ASERNIP-S. Australian and New Zealand Journal of Surgery. 2002; 72(8):580-582.

2001 •

Fitridge R. Evaluation of aortic stent grafting – the Australian experience. In: Whittemore A (Ed). Advances in Vascular Surgery. 2001;9:55–65.

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Results of Zenith Graft Patients This section summarises the patient demographics, procedures and follow-up results of patients whose AAA was treated with a Zenith graft. All data used for calculating the results in this section were received prior to 16 August 2008.

PPrree--ooppeerraattiivvee ppaattiieenntt ddeem mooggrraapphhiiccss Of the 787 Zenith graft patients enrolled in the audit the majority were male (85.1%, 670/787). The average age for Zenith graft patients was 75 years (SD± 6.9, ranging from 35-92 years, mode= 77 years). Patient fitness was measured using the American Society of Anaesthesiology (ASA) Rating. Table 1 below shows 32.6% (257/787) of Zenith patients were listed as healthy or only had mild systemic conditions (i.e. ASA I or II). The majority of patients were rated ASA III (59%, 464/787), i.e. as having severe systemic condition limiting lifestyle, e.g. angina. Almost half of Zenith graft patients (44.7%, 352/787) were considered unsuitable for open repair. For these patients the main reason for unsuitability was co-existent morbidity (76.2%, 269/352), other reasons that affected suitability were ‘hostile abdomen’ (21.3%) and ‘unfit for general anaesthetic’ (21.8%). Some patients were unsuitable for open repair for more than one reason.

Table 1. Pre-operative ASA in patients treated with Zenith graft* ASA I ASA II ASA III ASA IV % Zenith 2.5% 30.1% 59.0% 6.6% Patients * For patients where this was recorded adequately

Table 2 shows the survival and lost status of the EVAR audit cohort and the original enrolment. The 787 Zenith patients represent 82% of the original cohort captured by the audit (n=961). At seven years follow-up, about half of the Zenith patients are now deceased.

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Table 2. Enrolments, follow-up and mortality Data Total Percentage Operative data set 787 100% Public 215 27.3% Private 572 72.7% 1 Patients lost to follow-up 89 11.3% Deceased 391 49.6% Early* 12 1.5% Late 379 48.1% Patients lost due to age, frailty, refusal or following retirement or relocation of surgeon * Early death occurs within 30 days of the procedure, and is sometimes referred to as perioperative death. Late death implies death occurring more than 30 days post procedure. 1

3300--ddaayy tteecchhnniiccaall ssuucccceessss Technical success rates were calculated according to reporting standards established by the Ad Hoc Committee for standardized reporting practices in vascular surgery.2 The definition of primary technical success within the first 30 days after the operation includes: • Successful access to the arterial system using a remote site • Successful deployment of the endovascular graft with secure proximal and distal fixation • Absence of the following: death, conversion to open repair, Type I or III endoleaks, or graft limb obstruction • Use of the following: additional planned components, stents, angioplasty or adjunctive surgical procedures constitutes success*. * The Australian audit data does not distinguish between planned and unplanned procedures undertaken during the peri-procedural (24h) period.

Technical success for Zenith graft patients enrolled in the audit was 93.4% (735/787) M Moorrttaalliittyy PPeerriiooppeerraattiivvee m moorrttaalliittyy ASERNIP-S has received notification that half of the original cohort of patients has died (Table 2). ASERNIP-S has regularly linked the EVAR Audit database with the National Death Index data held by the AIHW. This information was last updated in July 2008. Table 3 shows the causes of death for the 12 patients who died within 30 days of their EVAR procedure, as shown by ICD-10 codes obtained from the National Death Index, and the number of days to death.

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Table 3. Cause of early mortality and days to death Cause of early death ICD-10 code Retroperitoneal haemorrhage and Myocardial I21.9 Infarction Cardiac and acidosis and AAA w/o rupture I71.4 Acute Myocardial Infarction I21.9 Acute Myocardial Infarction I21.9 Chronic IHD and renal failure I25.9 Right cerebro-vascular infarct and renal failure N19 Pulmonary embolism and AAA w/o rupture I71.4 Acute bowel rupture and AAA w/o rupture I71.4 Cerebral haemorrhage I61.9 Brain stem haemorrhage I61.3 Acute Myocardial Infarction I21.9 Ischaemic gut K559

Days to death 0 1 2 3 3 7 7 10 14 18 21 21

Of the 12 patients who died early, all were male and nine were described as ASA III or ASA IV. Patients who died early were aged 71-85 years and most were considered unsuitable for open repair. All except one patient had a pre-operative aneurysm diameter of more than 50mm.

M Miidd--tteerrm m aanndd lloonngg--tteerrm mm moorrttaalliittyy Table 4 shows mortality in the mid-term and long-term intervals following the 30 day postoperative period. Table 4. Cumulative mid to long term mortality Up to 3yrs* Up to 5yrs Up to 7yrs Total (N=787) 145 (18%) 250 (32%) 347 (44%) Age at EVAR 70 (N=622) Gender Male (N=670) Female (N=117) Aneurysm size at EVAR 50mm (N=559) ASA I (N=20) II (N=237) III (N= 464) IV(N=52)

>7yrs 379 (48%)

2 (12%) 12 (8%) 131 (21%)

4 (24%) 29 (20%) 217 (35%)

4 (24%) 38 (27%) 305 (49%)

4 (24%) 42 (29%) 333 (54%)

121 (18%) 24 (20%)

215 (32%) 35 (30%)

299 (45%) 48 (41%)

324 (48%) 55 (47%)

23 (12%) 119 (21%)

38 (19%) 203 (36%)

64 (32%) 269 (48%)

70 (35%) 293 (52%)

0 26 102 16

2 (10%) 45 (19%) 169 (36%) 29 (56%)

5 (25%) 67 (28%) 234 (50%) 33 (63%)

5 (25%) 75 (32%) 255 (55%) 35 (67%)

(0%) (11%) (22%) (31%)

* From 30 days to 3 years

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Table 5 shows the all cause mortality for the mid-term and long-term intervals following the 30 day postoperative period. Cardiac problems were the most common cause of death amongst the cohort, with cancer the second most common cause of death in the mid to long term.

Table 5. Cause of mid to long term mortality in Zenith patients1 Up to Up to 5yrs Up to 7yrs 3yrs*

>7yrs (Total %)

Unknown/Not Yet Known Cardiac Cancer Respiratory Stroke Rupture/Dissection2 Aneurysm without rupture Hepatic/Biliary/Renal Diabetes Digestive/Gastric Miscellaneous

66 (17.4%) 90 (23.7%) 66 (17.4%) 43 (11.3%) 26 (6.9%) 12 (3%) 11 (2.9%) 16 (4.2%) 9 (2.3%) 7 (1.8%) 30 (7.9%)

1 42 30 14 14 6 7 8 3 2 13

3 75 52 31 21 10 9 13 6 5 16

37 88 65 43 26 12 11 16 9 7 29

* From 30 days to 3 years.1 for cases with both date and cause of death data. See Appendix 2 for definitions of cause of death categories. 2Includes I71.00 Dissection of aorta unspecified site, not included in aneurysm-related death below.

A Anneeuurryyssm m--rreellaatteedd m moorrttaalliittyy aanndd rruuppttuurree For the purposes of these results, aneurysm-related death refers to death that occurs within 30 days of the original EVAR procedure (i.e. all early death), death within 30 days of a secondary procedure for the patient’s aneurysm and death assigned the following ICD-10 codes for cause of death. • • • • • • •

I71.00 Dissection of aorta unspecified site I71.2 Thoracic aortic aneurysm without rupture I71.3 Abdominal aortic aneurysm ruptured I71.4 Abdominal aortic aneurysm without rupture I71.8 Aortic aneurysm unspecified site ruptured I71.9 Aortic aneurysm unspecified site without rupture I72.3 Aneurysm of iliac artery

Currently, around seven years after EVAR, the total aneurysm-related death for Zenith graft patients enrolled in the audit is 4.4% (35/787), of these, 10 deaths were due to ruptured aneurysms (1.5%). The total of aneurysm-related deaths after the initial 30-day postoperative period is 2.9% (23/787).

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R Ruuppttuurree To date 16 Zenith graft patients have experienced a rupture of their aneurysm (2%). As mentioned above, ten of these patients died as a result of the rupture. The results of patients experiencing rupture can be seen in Table 6. Table 6. Zenith Graft Patient Experiencing Aneurysm Rupture Age at Max Time to Result of Current EVAR diameter rupture rupture status (years) before (months) rupture* (mm) 65 60 30 Deceased 78 60 60 Deceased 79 60 30 Deceased 72 48 71 Deceased 67 68 59 Deceased 76 45 12 Deceased 73 75 58 Deceased 81 81 69 Deceased 82 60 22 Deceased 85 53 43 Deceased 78 110

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