Long-term survival and late complications after repair of ruptured abdominal aortic aneurysms

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1 Long-term survival and late complications after repair of ruptured abdominal aortic aneurysms Jae-Sung Cho, MD, Peter Gloviczki, MD, Eugenio Martelli, MD, W. Scott Harmsen, MS, Michael E. Landis, MD, Kenneth J. Cherry, Jr., MD, Thomas C. Bower, MD, and John W. Hallett, Jr., MD, Rochester, Minn. Purpose: Long-term survival and late vascular complications in patients who survived repair of ruptured abdominal aortic aneurysms (RAAA) is not well known. The current study compared late outcome after repair of RAAA with those observed in patients who survived elective repair of abdominal aortic aneurysms (AAA). Methods: The records of 116 patients, 102 men and 14 women (mean age: 72.5 (8.3 years), who survived repair of RAAA (group I) between 1980 to 1989 were reviewed. Late vascular complications and survival were compared with an equal number of survivors of elective AAA repair matched for sex, age, surgeon, and date of operation (group II). Survival was also compared with the age and sex-matched white population of west-north central United States. Results: Late vascular complications occurred in 17% (20/116) of patients in group I and in 8% (9/116) in group II. Paraanastomotic aneurysms occurred more frequently in group I than in group II (17 vs. 8, p = 0.004). At follow-up, 32 patients (28%) were alive in group I (median survival: 9.4 years) and 53 patients (46%) were alive in group II (median survival: 8.7 years). Cumulative survival rates after successful RAAA repair at 1, 5, and 10 years were 86%, 64%, and 33%, respectively. These were significantly lower than survival rates at the same intervals after elective repair (97%, 74%, and 43%, respectively, p = 0.02) or survival of the general population (95%, 75%, and 52%, respectively, p < 0.001). Coronary artery disease was the most frequent cause of late death in both groups. Vascular and graft-related complications caused death in 3% (3/116) in group I and 1% (1/116) in group II. Cox proportional hazards modeling identified age (p = ), cerebrovascular disease (p = 0.009), and number of days on mechanical ventilation (p = 0.01) to be independent prognostic determinants of late survival in group I. Conclusions: Late vascular complications after repair of RAAA were higher and late survival rates lower than after elective repair. These data support elective repair of AAA. As two-thirds of the patients discharged after repair of RAAA are alive at 5 years, aggressive management of RAAA remains justified. (J Vasc Surg 1998;27: ) Management of the ruptured abdominal aortic aneurysm (RAAA) is the hallmark of vascular emergencies. Despite rapid advances in technology and patient care, it continues to be plagued with seemingly fixed mortality rates around 50% 1-4 that have From the Division of Vascular Surgery and Section of Biostastistics (Harmsen), Mayo Clinic and Mayo Foundation. Presented at the Twenty-first Annual Meeting of the Midwestern Vascular Surgical Society, Chicago, Ill., Sep , Reprint requests: Peter Gloviczki, MD, Professor of Surgery, Division of Vascular Surgery, Mayo Clinic, Rochester, MN Copyright 1998 by The Society for Vascular Surgery and International Society for Cardiovascular Surgery, North American Chapter /98/$ /6/88133 not changed over the last decade, 2,5,6 whereas the incidence of RAAA has continued to rise In some reports, mortality approached 90% when patients who were dying at home and en route to the hospital were also included. 3,12,13 Although immediate repair remains the only hope for survival for these patients, late complications also occur after aortic replacement. 14,15 Graft thrombosis has been reported as the most frequent late complication, followed by paraanastomotic aneurysm development, graftenteric fistulae, and graft infection. These complications result in significant mortality and morbidity and impact health-related quality of life of the patients. The classic report of Szilagyi 16 in 1966 established that elective repair of abdominal aortic 813

2 814 Cho et al. May 1998 aneurysm (AAA) prolongs life expectancy. Five-year survival in contemporary reports ranged from 50% to 68%. 5,17,18 In a population-based study from our institution, Hallett et al. 15 observed 6.8% late graftrelated complication rate in patients after repair of AAAs. However, the natural history of patients surviving repair of RAAA is less well documented, and only a few reports have been published with inconsistent results. 5,17,19,20 The purpose of the current study was to investigate late outcome in survivors of RAAA and to compare survival and late vascular complications with those observed in patients who survived elective AAA repair. Although the previous populationbased report from our institution focused on a portion of our patients, who live in the surrounding community, in this study we included all patients, who were referred to us with a RAAA during the study period. METHODS The clinical data of 118 patients, who survived repair of RAAA (for 30 postoperative days or until time of discharge if hospital stay was longer than 30 days) during a 10-year period between 1980 through 1989 at the Mayo Clinic, were reviewed. This group represents 50.6% of the 231 patients, who were admitted during this period with a RAAA, and includes all survivors discharged from the hospital after repair. Early data of the entire group was reported previously. 1 The long-term follow-up of the survivors after RAAA repair (group I) formed the basis for this report. Late vascular complications such as paraanastomotic aneurysms, graft infection, graft thrombosis, graft-enteric erosion, and survival were compared with a control group (group II) of survivors of elective AAA repair. The control group was chosen by matching sex, the operating surgeon, and the date of operation (within 18 months of the case), such that approximately equal distribution of gender and age within similar time frame can be obtained with that of RAAA group. If the patient was alive, but did not return for follow-up within the past year, information was obtained through telephone conversation with the patient or referring physician. Date and the cause of death were determined by review of hospital records or by acquisition of death certificate or autopsy reports. Reports of imaging studies, ultrasonography (US), and computed tomography (CT) were reviewed to determine late vascular complications. True aneurysm was defined as an increase in diame- ter of greater than 50% of the expected normal diameter of the aorta or iliac artery on US or CT 21 : 3.0 cm for aorta and 2.0 cm for iliac artery. Focal bulging of artery at the anastomotic site was considered pseudoaneurysm. For survival calculation, day 0 was defined as postoperative day 30, if discharged from the hospital before that time, or the date of discharge if hospital stay exceeded 30 days. The Kaplan-Meier survival method was used to estimate survival and to detect differences in patient survival rates and survival-free of vascular complications between the two groups. The log-rank test was used to compare groups I and II for survival-free of vascular complications and overall patient survival. Survival of the groups was also compared with the age and sex-matched white population of west-north central United States and the significance determined by the one-sample logrank test. Separate univariate analyses were performed to determine prognostic factors predictive of longterm survival within each group. Candidate factors with p < 0.1 and an incidence of 10% were entered into the multivariate analysis model. Cox proportional hazards modeling with stepwise variable selection was used to determine the best fitting multivariate model for these patients. The study was reviewed and approved by the Mayo Institutional Review Board. RESULTS Demographics. One hundred and eighteen patients, 103 men and 15 women, were discharged from the hospital after repair of RAAA. Two patients were lost to follow-up, and they were excluded from the study. Therefore the clinical data of 116 patients, 102 men and 14 women, were analyzed (group I). Mean age was 72.5 years (range: 53 to 91). Late clinical outcome was also assessed in a similar, matched group of 116 patients, 102 men and 14 women with a mean age of 72 years (range: 50 to 89), who were selected from early survivors after elective AAA repair (group II). The mean size of AAA in group II was 5.9 ± 1.9 cm. Sufficient information on the size of the RAAA was not available. Median follow-up was 7.0 years (range:1 month to 17 years) in group I and 7.2 years (range: 5 months to 16.4 years) in group II. Median follow-up time of those who were alive at the time of review was 9.4 and 8.7 years in groups I and II, respectively. Follow-up was complete within the past 18 months in 87.5% in group I and in 81.1% in group II. Late vascular complications. Late vascular complications were detected in 20 patients (17%) in group I, and in 9 patients (8%) in group II (p < 0.05)

3 Volume 27, Number 5 Cho et al. 815 Table I. Vascular and graft-related late complications after RAAA repair (group I) and elective AAA repair (group II) Group I Group II (n = 116) (n = 116) Number of Number of Late complications patients (%) patients (%) Fig. 1. Cumulative survival after repair of ruptured and nonruptured abdominal aortic aneurysm. (Table I). Paraanastomotic aneurysms occurred more frequently in group I (22 aneurysms in 17 patients) than in group II (8 aneurysms in 8 patients) (p = 0.004). Paraanastomotic aneurysm included both true aneurysmal degeneration of native arteries and pseudoaneurysm, which resulted from anastomotic failure. One proximal pseudoaneurysm (0.9%) was detected in each of the RAAA repair and the elective AAA repair groups. True aneurysm in the proximal aorta was noted in 12 patients (10%) in group I and in 3 patients (3%) in group II. Similarly, true aneurysmal degeneration of the native artery at the distal anastomosis occurred in 10 patients (9%) in group I and in 4 patients (3%) in group II. Reoperation for enlarging or ruptured paraanastomotic aneurysms was required only in four patients in group I and in one patient in group II. One patient presented with a ruptured 7 cm pseudoaneurysm of proximal aorta 12 years after his RAAA repair. Repair was complicated by intestinal ischemia, and the patient ultimately succumbed of myocardial infarction. The second patient developed thoracoabdominal aneurysm 4 years after RAAA repair. He survived the second operation for 7 years and died of coronary artery disease (CAD). The third patient underwent repair of bilateral iliac artery aneurysms 9 years after RAAA repair and was alive at the time of review. The last patient with arteriomegaly required aortobifemoral bypass 17 months after initial surgery, and died of ruptured thoracic aortic aneurysm 9 months later. The only patient in group II, who had a false aneurysm, developed a graft-duodenal fistula at 11 years from elective AAA repair. He underwent axillobifemoral bypass and was alive 6 months later. Postoperative imaging data (US and CT) were available in 56 patients (48%) in group I and in 63 patients (54%) in group II. Paraanastomotic aneurysms True 16 (14) 7 (6) False 1 (1) 1 (1) Graft infection 3 (3) 2 (2) Graft occlusion 2 (2) 0 (0) Graft-enteric fistula 0 (0) 1 (1) Anastomotic disruption 1 (1) 0 (0) Total* 20 (17) 9 (8) *A patient may have more than one vascular or graft complication. Paraanastomotic aneurysms were detected at a median of 1.3 years and 2.4 years after RAAA and elective AAA repair, respectively. Graft occlusion occurred in two patients in group I and none in group II. Both patients underwent successful repair without limb loss or mortality. Three graft infections occurred in group I and two in group II. Two patients in group I were treated with antibiotics only until their death 8 years later. The last patient underwent percutaneous drainage and on antibiotics was alive and well at 5 years. One patient developed graft infection after groin catheterization 1 year after elective repair of AAA. The patient underwent multiple staged operations, including extraanatomic bypass, removal of the graft, and replacement with new aortobifemoral graft over the next 2 years. He survived 2 years free of graft infection and died of renal failure. The second patient developed graft infection after bowel resection for intestinal infarction after elective AAA repair. He died of sepsis from persistent psoas abscess 5 years later. Graft-enteric fistula was detected in one patient in group II. As noted earlier, this patient also developed proximal paraanastomotic aneurysm. Late survival. At follow-up, 32 patients (28%) were alive in group I (median survival: 7.0 years) and 53 patients (46%) in group II (median survival: 7.2 years). Cumulative survival rates after successful RAAA repair at 1, 5, and 10 years were 86%, 64%, and 33%, respectively. These were significantly lower compared with survival rates at the same intervals after elective repair (97%, 74%, and 43%, respectively, p = 0.02) (Fig. 1) as well as expected survival of

4 816 Cho et al. May 1998 Table II. Causes of late death in survivors of ruptured and elective AAA repair Group I Group II number of number of patients (%) patients (%) Fig. 2. Cumulative survival after repair of ruptured and matched general population. CAD 28 (33) 19 (30) Pulmonary disease 11 (13) 11 (17) Cancer 17 (20) 14 (22) Cerebrovascular disease 13 (15) 7 (11) Renal failure 4 (5) 3 (5) Anastomotic disruption 1 (1) 0 (0) Graft-enteric fistula 0 (0) 0 (0) Graft infection 0 (0) 1 (2) Other 10 (12) 8 (13) Total 84 (100) 63 (100) the number of days on mechanical ventilation to be the independent prognostic factors of late death. In group II, age alone was noted to be an independent determinant of long-term survival by multivariate analysis (Table IV). Fig. 3. Cumulative survival after repair of ruptured and nonruptured abdominal aortic aneurysm and matched general population. the white population of west-north central United States (95%, 75%, and 52%, respectively, p = 0.001) (Fig. 2). The difference between the observed and the expected survival rates in the nonruptured group was statistically not significant (Fig. 3). Coronary artery disease was the most common cause of death in both groups (Table II). In group I, pulmonary disease, cancer, and cerebrovascular disease were additional causes of death, in decreasing frequency. In group II, cancer was the second most frequent cause, followed by pulmonary disease. Death was directly related to late graft complications in three patients in group I and in one patient in group II. One patient in group I died of hemorrhagic shock shortly after discharge from the hospital. Two patients died of ruptured paraanastomotic aneurysms, one true and one false aneurysm. Univariate analysis identified 10 different factors as possible prognostic determinants of late death in group I (Table III). However, multivariate analysis found advanced age, cerebrovascular disease, and DISCUSSION Ruptured abdominal aortic aneurysm continue to have high early mortality, and only 50% or less of those who are admitted with this diagnosis will ultimately leave the hospital. Data on late survival and vascular and graft-related complications in this group of patients have been controversial. Some studies have reported that life expectancy of survivors of RAAA repair was the same as that of the general population or that of survivors of elective AAA repair. Fielding et al. 22 observed 5-year overall survival rates of 57% and 65% after repair of RAAA and nonruptured AAA, respectively, and concluded that survival did not differ between the two groups. Rohrer et al., 5 in a review of 65 patients who survived RAAA repair, noted 1-, 5-, and 10-year survival rates that were similar to those for 100 survivors of elective AAA repair and matched samples from the general population. More recently, Stonebridge et al. 13 observed 40% survival rate in survivors after RAAA repair and 45% after repair of nonruptured AAA at 8 years, a difference that was statistically not significant. Data from others 17,23 had similar conclusions. However, Johnston et al. 19 in the Canadian cooperative study collected data on 58 RAAA repair survivors and found that 1- and 5-year survival rates were 88% and 53%, whereas those after elective repair had survival rates of 96% and 71%, respectively. Our data also demonstrated a decreased survival in those who were discharged from the hospital after

5 Volume 27, Number 5 Cho et al. 817 Table III. Prognostic determinants of late survival in the survivors of RAAA Group I Risk Univariate Multivariate factor analysis analysis p value p value Odds Confidence ratio interval Sex (female) 0.02 NS NS NS Age CAD 0.05 NS NS NS Cerebrovascular disease Days on mechanical ventilation Tracheostomy NS NS NS Myocardial infarction 0.04 NS NS NS Highest creatinine level 0.01 NS NS NS Type of rupture (free vs. contained) 0.06 NS NS NS Intraoperative urine output 0.02 NS NS NS Table IV. Prognostic determinants of late survival in survivors of elective AAA repair Group II Risk Univariate Multivariate factor analysis analysis p value p value Odds Confidence ratio interval Age/10 years Days on mechanical ventilation 0.06 NS NS NS Highest creatinine 0.06 NS NS NS Smoking history* 0.07 NS NS NS Baseline creatinine 0.04 NS NS NS Total blood transfusion 0.09 NS NS NS Cross clamp time 0.05 NS NS NS *Data available in 101 patients and were excluded from final multivariate analysis. repair of RAAA when compared with those who underwent elective repair or when compared with survival of the general population. Although both studies showed decreased 5-year survivals after RAAA, cumulative survival rates of 53% and 64% indicate that a substantial number of patients still have satisfactory long-term survival after surgical treatment for RAAA. Atherosclerosis remains the key deterrent to late survival of these patients with CAD, causing 33% and 30% of deaths in patients who survived RAAA repair and elective AAA repair, respectively. These data are similar to those reported by Hertzer et al. 24 and by others Our population-based study showed that 8-year survival rates were 40% after AAA repair for patients with CAD and 60% for those without CAD. There was a 5% risk of stroke at 5 years and a 10% risk of stroke at 10 years in patients who survived AAA repair. 29 In the current study, cerebrovascular disease caused 15% and 11% late deaths in groups I and II, respectively. Multivariate analysis in our study also confirmed that cerebrovascular disease, in addition to age and chronic obstructive pulmonary disease, were independent predictors of late death of these patients. Age and chronic obstructive pulmonary disease was also found to predict late death in other studies on RAAA. 27,28 In addition to an excessive early mortality rate after repair of RAAA, patients who leave the hospital will continue to be exposed to risks of late vascular and graft-related complications. Although data after elective repair on late complications are available, risks of graft complications in survivors of RAAA are less well known. In our 36-year population-based study, Hallett et al. 15 reported a 6.8% late, major graft-related complication rate after AAA

6 818 Cho et al. May 1998 repair, most after elective operations. Paraanastomotic aneurysm was the most frequent complication (3%), followed by graft thrombosis (2%), graft enteric erosion/fistula (1.6%), graft infection (1.3%), and anastomotic hemorrhage (1.3%). 15 The current study, which included all survivors of repair of RAAA between 1980 and 1989 from our referred population, confirmed an 8% late vascular complication rate after elective repair, but it also found a significantly higher, 17%, complication rates in the survivors of RAAA repair. True paraanastomotic aneurysms were the most frequent. Despite a 15% incidence of paraanastomotic aneurysm development, only 4% (five patients) were clinically significant, i.e., expanding or symptomatic, which necessitated in a surgical intervention or death due to rupture. Patients with small or clinically stable aneurysms were observed, as were those with prohibitive medical comorbidities or terminal illness. Other graft complications such as graft thrombosis, graft infection, and graft-enteric fistula occurred in few cases with equal incidences. In this study, radiographic imaging was obtained in half of the patients in both groups. It indicates that the 15% incidence of paraanastomotic aneurysms after repair of RAAA may indeed be an underestimate. Edwards et al. 30 predicted an incidence of paraanastomotic aneurysm to be as high as 27% at 15 years after AAA repair. These data suggest the need for postoperative surveillance. The cause of proximal paraanastomotic aneurysms is different in true from false aneurysms. Progression of atherosclerotic degenerative dilatation of the aorta is the cause of true aneurysms, whereas false aneurysms may result from graft infection, anastomotic failure, or graft-enteric erosion. A more frequent finding of proximal aneurysm after repair of RAAA may also be due to failure to assess the proximal extent of the ruptured AAA or acceptance of a dilated aneurysmal neck to facilitate repair and save the life of the patient. Another explanation for this may be that the aneurysms that rupture may be a more virulent type than those that do not rupture, and biologically behave differently. It is particularly of interest to note that in seven of the survivors of RAAA repair thoracic aortic dissection or aneurysmal degeneration were noted, in contrast to none in the elective AAA repair group. Metalloproteinases play an important role in aneurysm disease Comparison of matrix metalloproteinases levels in patients with RAAA with nonruptured AAA would be helpful to differentiate the pathogenesis between the two. Because median time of detection of paraanastomotic aneurysms after repair of RAAA was within the first 2 years, our current recommendation is to obtain an US or a CT scan in every patient at 1 year after the operation. If the imaging at 1 year shows no aneurysm or other graft-related complication, in the current era of cost containment, a repeat imaging study before 3 to 5 years is difficult to justify. Ultrasound is adequate in detecting and following true paraanastomotic aneurysms. A pseudoaneurysm of any size and a clinically significant true aneurysm warrant a CT scan to better delineate the anatomy. A continuing rise in the incidence of ruptured AAA has been witnessed in recent years 7-11 without improvement in operative mortality. In addition, patients after repair of ruptured AAA have an increased risk of late vascular and graft-related complications and a decreased late survival compared with those who have undergone elective aneurysm repair. When late survival was separately analyzed for those who survived for at least 1 year, there was no significant difference in survival between the two groups. This may be attributable to lingering effects of physiologic insults rendered by rupture and its repair for up to 1 year. It suggests that the survivors of RAAA repair warrant close monitoring of their overall health status and appropriate interventions at least for 1 year after repair. These data support elective repair of AAA. As two-thirds of the patients discharged after repair of RAAA are alive at 5 years, aggressive efforts at repair of RAAA remain justified. We thank Mrs. Marcia Simonson for her editorial assistance. REFERENCES 1. Gloviczki P, Pairolero PC, Mucha P Jr, Farnell MB, Hallett JW Jr, Ilstrup DM, et al. Ruptured abdominal aortic aneurysms: repair should not be denied. J Vasc Surg 1992; 15: Hardman DT, Fisher CM, Patel MI, Neale M, Chambers J, Lane R, et al. Ruptured abdominal aortic aneurysms: Who should be offered surgery? J Vasc Surg 1996;23: Johansen K, Kohler TR, Nicholls SC, Zierler RE, Clowes AW, Kazmers A. Ruptured abdominal aortic aneurysm: the Harborview experience. J Vasc Surg 1991;13: Ouriel K, Geary K, Green RM, Fiore W, Geary JE, DeWeese JA. Factors determining survival after ruptured aortic aneurysm: the hospital, the surgeon, and the patient. J Vasc Surg 1990;11: Rohrer MJ, Cutler BS, Wheeler HB. Long-term survival and quality of life after ruptured abdominal aortic aneurysm. Arch Surg 1988;123: Katz DJ, Stanley JC, Zelenock GB. Operative mortality rates for intact and ruptured abdominal aortic aneurysms in Michigan: an eleven-year statewide experience. J Vasc Surg 1994; 19:

7 Volume 27, Number 5 Cho et al Rutledge R, Oller DW, Meyer AA, Johnson GJ Jr. A statewide, population-based time-series analysis of the outcome of ruptured abdominal aortic aneurysm. Ann Surg 1996;223: Lindsay TF, Johnston KW. Ruptured abdominal aoric aneurysm: from diagnosis to discharge. In: Whittemore AD, Bandyk DF, Cronenwett JL, Hertzer NR, White RA, editors. Advances in vascular surgery. St Louis: Mosby Year Book; p Nasim A, Sayers RD, Thompson MM, Healey PA, Bell PR. Trends in abdominal aortic aneurysms: a 13 year review. Eur J Vasc Endovasc Surg 1995;9: Samy AK, Whyte B, MacBain G. Abdominal aortic aneurysm in Scotland. Br J Surg 1994;81: Mealy K, Salman A. The true incidence of ruptured abdominal aortic aneurysms. Eur J Vasc Surg 1988;2: Ernst CB. Abdominal aortic aneurysm. N Engl J Med 1993;328: Stonebridge PA, Callam MJ, Bradbury AW, Murie JA, Jenkins AM, Ruckley CV. Comparison of long-term survival after successful repair of ruptured and non-ruptured abdominal aortic aneurysm. Br J Surg 1993;80: Plate G, Hollier LH, O Brien P, Pairolero PC, Cherry KJ Jr, Kazmier FJ. Recurrent aneurysms and late vascular complications following repair of abdominal aortic aneurysms. Arch Surg 1985;120: Hallett JW Jr, Marshall DM, Retterson TM, Gray DT, Bower TC, Cherry KJ Jr, et al. Graft-related complications after abdominal aortic aneurysm repair: reassurance from a 36-year population-based experience. J Vasc Surg 1997;25: Szilagyi DE, Smith RF, DeRusso FJ, Elliott JP, Sherrin FW. Contribution of abdominal aortic aneurysmectomy to prolongation of life. Ann Surg 1966;164: Appleberg M, Coupland GAE, Reeve TS. Ruptured abdominal aortic aneurysm: Long-term survival after operation. Aust N Z J Surg 1980;50: Hollier LH, Plate G, O Brien PC. Late survival after abdominal aortic aneurysm repair: influence of coronary artery disease. J Vasc Surg 1984;1: Johnston KW. Ruptured abdominal aortic aneurysm: six-year follow-up results of a multicenter prospective study. Canadian Society for Vascular Surgery Aneurysm Study Group. J Vasc Surg 1994;19: Graham KJ, Cole DS, Barrat-Boyes BG. The surgical management of ruptured abdominal aneurysm: a ten-year experience. Aust N Z J Surg 1971;41: Johnston KW, Rutherford RB, Tilson MD, Shah DM, Hollier LH, Stanley JC. Suggested standards for reporting on arterial aneurysms. J Vasc Surg 1991;13: Fielding JWL, Black J, Ashton F, Slaney G, Campbell DJ. Diagnosis and management of 528 abdominal aortic aneurysms. BMJ 1981;283: Christenson J, Eklof B, Gustafson I. Abdominal aortic aneurysms: Should they all be resected? Br J Surg 1977; 64: Hertzer NR. Fatal myocardial infarction following abdominal aortic aneurysm resection; three hundred forty-three patients followed 6-11 years postoperatively. Ann Surg 1980;192: Reigel MM, Hollier LH, Kazmier FJ, O Brien PC, Pairolero PC, Cherry KJ Jr, et al. Late survival in abdominal aortic aneurysm patients: the role of selective myocardial revascularization on the basis of clinical symptoms. J Vasc Surg 1987; 5: Hicks GL, Eastland MW, DeWeese JA, May AG, Rob CG. Survival improvement following aortic aneurysm resection. Ann Surg 1975;181: Chen JC, Hildebrand HD, Salvian AJ, Taylor DC, Strandberg S, Myckatyn TM, et al. Predictors of death in nonruptured and ruptured abdominal aortic aneurysms. J Vasc Surg 1996;24: Koskas F, Kieffer E. Surgery for ruptured abdominal aortic aneurysm: early and late results of a prospective study by the AURC in Ann Vasc Surg 1997;11: Hallett JW Jr. Abdominal aortic aneurysm: natural history and treatment. Heart Disease Stroke 1992;1: Edwards JM, Teefey SA, Zierler RE, Kohler TR. Intraabdominal paraanastomotic aneurysms after aortic bypass grafting. J Vasc Surg 1992;15: Thompson RW, Parks WC. Role of matrix metalloproteinases in abdominal aortic aneurysms. Ann New York Acad Sci 1996;800: Sakalihasan N, Delvenne P, Nusgens BV, Limet R, Lapiere CM. Activated forms of MMP2 and MMP9 in abdominal aortic aneurysms. J Vasc Surg 1996;24: Patel MI, Melrose J, Ghosh P, Appleberg M. Increased synthesis of matrix metalloproteinases by aortic smooth muscle cells is implicated in the etiopathogenesis of abdominal aortic aneurysms. J Vasc Surg 1996;24: Freestone T, Turner RJ, Coady A, Higman DJ, Greenhalgh RM, Powell JT. Inflammation and matrix metalloproteinases in the enlarging abdominal aortic aneurysm. Arterioscler Thrombo Vasc Biol 1995;15: Submitted Sep. 12, 1997; accepted Dec. 10, DISCUSSION Dr. Walter J. McCarthy, III (Chicago, Ill.) I would like to congratulate the authors for putting together this very interesting retrospective review of survival and the complications after elective aneurysm repair and after ruptured aneurysm repair. They compared 116 patients who survived ruptured aneurysm and they compared those to age and sex-matched controls who had had elective surgery. Interestingly, the elective patients had a slightly better survival at 1, 5, and 10 years. A fascinating and important finding was that the ruptured group were more inclined toward paranastomotic aneurysms than were those who were repaired on an elective basis. I think that this might persuade all of us to adopt some sort of a follow-up CT program for our aneurysm patients. This

8 820 Cho et al. May 1998 brings me to my first question. Should we CT scan survivors of ruptured aneurysm more conscientiously than those who have had elective repair? My second question involves the survival curves. In looking through the manuscript that you provided, the actual life tables were not presented. But looking at the actual graphic representation, the curves seem to separate in the first 6 months and then run rather parallel, and I wondered what those patients died of in the first 6 months, did they die of complications of the operation? In other words, the true survival might actually predict longevity that was equal to the elective aneurysm repair. My last question may be a somewhat difficult one because it focuses on the follow-up of 87% in the ruptured group and 81% in the elective cases. Inevitably, the last few patients who cannot be contacted or located in such a study probably have died. I wondered how you handled these patients. If you assume that they were alive, which certainly is probably partly wrong, then the conclusions that you have come to that the group I and group II patients actually have different survival is hard to support. Have you used the National Death Index? The National Death Index is a service that allows a very accurate tracking of mortality nationwide that solves the problem in cases like this and in follow-up of cases like this. I enjoyed this paper very much and I feel that it has really taught us a number of practical points about ruptured aneurysm follow-up about perianastomotic aneurysms. I would like to thank the Society for the privilege of presenting at this discussion. Dr. Cho. Thank you for your kind words and insightful comments. Regarding your first question about followup imaging of these patients, based on our data, our recommendation at the present time would be to get a CT scan within the first year. If the CT scan is normal, I would think that it would be rather difficult to justify getting another repeat scan within the next 3 to 5 years given this era of cost containment. However, if the CT scan was found to be abnormal with evidence of graft-related complications, I think that it would be mandatory to follow these patients as necessary, probably at least every year or so. With respect to survival, you had two questions. The focus of the study was not only to define the actual cause of death, but death by any case. Death was one end point that nobody can argue. We tried to get the actual cause of death by contacting the family s referring physician, if the patient had already expired, or the patient s family or death certificates and autopsy reports. However, there were some states that would not release death certificates, and there were seven patients whose death certificates we just could not obtain. Those who were lost to follow-up were considered dead for the purpose of survival calculation. Your second question was whether we assessed the cause of death in the first 6 months. We did not actually look into that, but my impression is that these were probably related to not only coronary artery disease but also related to the aneurysm surgery such as ischemic changes of the GI tract and other complications. Again, I do not have actual numbers to quote you. BOUND VOLUMES AVAILABLE TO SUBSCRIBERS Bound volumes of the Journal of Vascular Surgery for 1998 are available to subscribers only. They may be purchased from the publisher at a cost of $ for domestic, $ for Canadian, and $ for international subscribers for Vol. 27 (January to June) and Vol. 28 (July to December). Price includes shipping charges. Each bound volume contains a subject and author index, and all advertising is removed. Copies are shipped within 60 days after publication of the last issue in the volume. The binding is durable buckram with the journal name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact Subscription Services, Mosby, Inc., Westline Industrial Dr., St. Louis, MO , USA. In the United States call toll free , ext In Missouri or foreign countries call Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular Journal subscription.