Will endovascular repair replace open surgery for abdominal aortic aneurysm repair?

OBJECTIVE: To evaluate of the impact of endovascular aneurysm repair on the rate of open surgical repair and on the overall treatment of abdominal aortic aneurysms (AAAs). METHODS: All patients with AAA who were treated during two consecutive 40-month periods were reviewed. During the first period, only open surgical repair was performed; during the subsequent 40 months, endovascular repair and open surgical repair were treatment options. RESULTS: A total of 727 patients with AAA were treated during the entire period. During the initial 40 months, 268 patients were treated with open surgical repair, including 216 infrarenal (81%), 43 complex (16%), and 9 ruptured (3%) aortic aneurysms. During the subsequent 40 months, 459 patients with AAA were treated (71% increase). There was no significant change in the number of patients undergoing open surgical repair and no significant difference in the rate of infrarenal (238 [77%]) and complex (51 [16%]) repairs. A total of 353 patients were referred for endovascular repair. Of these, 190 (54%) were considered candidates for endovascular repair based on computed tomography or arteriographic morphologic criteria. Analyzing a subgroup of 123 patients, the most common primary reasons for ineligibility for endovascular repair were related to morphology of the neck in 80 patients (65%) and of the iliac arteries in 35 patients (28%). A total of 149 patients underwent endovascular repair. Of these, the procedure was successful in 147 (99%), and 2 (1%) patients underwent surgical conversion. The hospital death rate was 0%, and the 30-day death rate was 1%. During a follow-up period of 1 to 39 months (mean 12 +/- 9), 21 secondary procedures to treat endoleak (20) or to maintain graft limb patency (1) were performed in 17 patients (11%). There were no aneurysm ruptures or aneurysm-related deaths. CONCLUSIONS: Endovascular repair appears to have augmented treatment options rather than replaced open surgical repair for patients with AAA. Patients who previously were not candidates for repair because of medical comorbidity may now be safely treated with endovascular repair.     

Effect of β-blocker on aneurysm sac behavior after endovascular abdominal aortic repair

Objective

This study was conducted to determine whether β-blocker (BB) therapy is associated with abdominal aortic aneurysm (AAA) sac regression after endovascular abdominal aortic repair (EVAR).

Is preoperative cardiac evaluation for abdominal aortic aneurysm repair necessary?

Purpose: It is reported that 25% to 50% of patients with abdominal aortic aneurysms (AAA) have severe coronary artery disease (CAD) and should undergo an aggressive cardiac workup before AAA repair. In contrast, it has been our policy that patients referred for AAA repairs undergo no cardiac testing before surgery.Methods: This report reviews the last 113 consecutive patients who underwent elective AAA repair by the senior author using this policy. Seventy-four patients (group A) had only an electrocardiogram before surgery. The remaining 39 patients (group B) were referred having already had additional testing that included a thallium stress test (n = 20), echocardiogram (n = 18), multiple gated acquisition (MUGA) scan (n = 3), cardiac catheterization (n = 8), or some combination of these.Results: There was no statistical difference between group A and group B with regard to age, sex, tobacco use or history of coronary artery disease, diabetes mellitus, stroke (CVA), hypertension, peripheral vascular disease, or chronic obstructive pulmonary disease. Group B more commonly had a history of myocardial infarction (41% vs 19%, p < 0.03) and congestive heart failure (23% vs 7%, p < 0.03). During surgery there was no significant differences in blood loss, transfusion requirements, or operative times. There were no myocardial infarctions in group A and two (5.1%) in group B, which was not significantly different. Other complications, such as CVA, renal failure, pulmonary failure, pneumonia, wound infection, and hemorrhage, were not significantly different between the two groups. Postoperative hospital stay was not significantly different. There were three deaths in the entire series (2.7%), and only one in group B was cardiac-related in a patient with known end-stage cardiac disease and a symptomatic 8 cm AAA.Conclusions: These data indicate that most patients with AAA can safely undergo repair with no cardiac workup and that cardiac workup before AAA repair contributes little information that impacts on treatment or final clinical outcome. We conclude that cardiac testing in preparation for AAA repair is not usually necessary and that intraoperative hemodynamic management may be the most important variable in determining outcome. (J Vasc Surg 1997;25:152-6.)     

Two decades of abdominal aortic aneurysm repair: have we made any progress?

PURPOSE: Over the past 20 years, there have been numerous advances in our ability to detect and to treat abdominal aortic aneurysms (AAAs). We hypothesized that these advances would lead to (1) an increase in the rate of elective repair and a decrease in the incidence of ruptured AAA (rAAA) and (2) a decrease in operative deaths for both elective AAA (eAAA) and rAAA. METHODS: To test these hypotheses, we investigated the incidence and outcomes of eAAA and rAAA surgery between 1979 and 1997, using the National Hospital Discharge Survey. This data set is a randomized, stratified sample representing discharges from the nation's acute care, nonfederally funded hospitals. Codes from the International Classification of Diseases, Ninth Revision were used to identify our study population. RESULTS: Over the past 19 years, there has been no change in the incidence rate of eAAA repair (range, 44.1-77.9 per 100,000). Moreover, the incidence of rAAAs presenting to the nation's hospitals has not changed (range, 6.6-16.3 per 100,000). There has been no consistent improvement over time in operative deaths associated with either eAAA or rAAA repair (average rates over the study period: eAAA, 5.6%; rAAA, 45.7%). Significant predictors of death from eAAA in patients included an age older than 80 years, African American race, congestive heart failure (CHF), and diabetes (P<.0001 for all). Significant predictors of death from rAAA in patients included age older than 70 years, African American race, female sex, renal failure, and a hospital bed size more than 500 (P<.05 for all). CONCLUSION: On a national level, over the past 19 years, our ability to identify and to treat patients with AAA has not improved. Advances in technology and critical care have not affected outcome. Regionalization of care, screening of high-risk populations, and endovascular repair are strategies that might allow further improvement in the outcome of patients with aneurysmal disease.     

To what extent has endovascular aneurysm repair influenced abdominal aortic aneurysm management in the state of Illinois?

PURPOSE: This study was performed using population-based data to determine the changing trends in the techniques for abdominal aortic aneurysm (AAA) repair in the state of Illinois during the past 9 years and to examine the extent to which endovascular aneurysm repair (EVAR) has influenced overall AAA management. METHODS: All records of patients who underwent AAA repair (1995 to 2003 inclusive) were retrieved from the Illinois Hospital Association COMPdata database. The outcome as determined by in-hospital mortality was analyzed according to intervention type (open vs EVAR) and indication (elective repair vs ruptured AAA). Data were stratified by age, gender, and hospital type (university vs community setting) and then analyzed using both univariate (chi 2 , t tests) and multivariate (stepwise logistic regression) techniques. RESULTS: Between 1995 and 2003, 14,517 patients underwent AAA repair (85% for elective and 15% for ruptured AAA). The average age was 71.4 +/- 7.9 years, and 76% were men. For elective cases, open repair was performed in 86% and EVAR in 14%; and for ruptured cases, open repair in 97% and EVAR in 3%. Elective EVAR was associated with lower in-hospital mortality compared with open repair regardless of age. No differences were observed with age after either type of repair for a ruptured aneurysm. Men had a lower in-hospital mortality compared with women for open repair of both elective and ruptured aneurysms. For EVAR, the mortality of an elective repair was lower in men, but there was no difference after a ruptured AAA. In men, the difference in mortality between elective open repair and EVAR was significant; the type of institution did not influence outcome. Patients >80 years of age had a higher mortality after open repair for both elective and ruptured AAA and after EVAR of a ruptured AAA. The average length of stay was 9.9 days for open elective repair, 13.1 days after open repair of a ruptured AAA, and 3.6 days for EVAR. The independent predictors of higher in-hospital mortality were female gender, age >80 years, diagnosis (ruptured vs open), and procedure (open vs EVAR). The year of the procedure and type of hospital (university vs community) were not predictive of outcome. CONCLUSIONS: EVAR has had a significant impact on AAA management in Illinois over a relatively short time period. In this population-based review, EVAR was associated with a significantly decreased in-hospital mortality and length of stay. Octogenarians had higher mortality after both types of repair, with the exception of elective EVAR.     

Diameter of abdominal aortic aneurysm and outcome of endovascular aneurysm repair: does size matter? A report from EUROSTAR

OBJECTIVES: This study was undertaken to determine the effect of the preoperative diameter of abdominal aortic aneurysms on the midterm outcome after endovascular abdominal aneurysm repair (EVAR). METHOD: The data for 4392 patients who had undergone EVAR were analyzed. Patients were enrolled over 6 years to June 2002 in the EUROSTAR database. Outcomes were compared between three groups defined by the preoperative diameter of the aneurysm: group A (n = 1962), 4.0 to 5.4 cm; group B (n = 1528), 5.5 to 6.4 cm; and group C (n = 902), 6.5 cm or larger. Patient characteristics, details of aortoiliac anatomy, operative procedures, old or current device generation, and postoperative complications in the three patient groups were compared. Outcome events included aneurysm-related death, unrelated death, conversion, and post-EVAR rupture of the aneurysm. Life table analysis and log-rank tests were used to compare outcome in the three study groups. Multivariate Cox models were used to determine whether baseline and follow-up variables were independently associated with adverse outcome events. RESULTS: Patients in group C were significantly older than patients in groups A and B (73 years vs 70 and 72 years, respectively; P =.003 - P <.0001 for different group comparisons), and more frequently were at higher operative risk (American Society of Anesthesiologists classification >or=3; 63% vs 48% and 54%; P =.0002-P <.0001). Device-related (type I) endoleaks were more frequently observed at early postoperative arteriography in group C compared with groups A and B (9.9% vs 3.7% and 6.8%; P =.01-P <.0001). Postoperatively systemic complications were more frequently present in group C (17.4% vs 12.0% in group A and 12.6% in group B; P <.0001 and.001). The first-month mortality was approximately twice as high in group C compared with the other groups combined (4.1% vs 2.1%; P <.0001). Late rupture was most frequent in group C. Follow-up results at midterm were less favorable in groups C and B compared with group A (freedom from rupture, 90%, 98%, and 98% at 4 years in groups C, B, and A, respectively; P <.0001 for group C vs groups A and B). Aneurysm-related death was highest in group C (88% freedom at 4 years, compared with 95% in group B and 97% in A; P =.001 and P <.0001, respectively; group B vs A, P =.004). The annual rate of aneurysm-related death in group C was 1% in the first 3 years, but accelerated to 8.0% in the fourth year. Incidence of unrelated death also was higher in groups C and B than in group A (76% and 82% freedom at 4 years vs 87%; P <.0001 for both comparisons). Ratio of aneurysm-related to unrelated death was 23%, 21%, and 50% in groups A, B, and C, respectively. Cox models demonstrated that the correlation between large aneurysms (group C) and all assessed outcome events was independent and highly significant. Older generation devices had an independent association with aneurysm-related and unrelated deaths (P =.02 and P =.04, respectively). However, this correlation was less strong than large aneurysm diameter (P =.0001 and P =.0009, respectively). CONCLUSIONS: The midterm outcome of large aneurysms after EVAR was associated with increased rates of aneurysm-related death, unrelated death, and rupture. Reports of EVAR should stratify their outcomes according to the diameter of the aneurysm. Large aneurysms need a more rigorous post-EVAR surveillance schedule than do smaller aneurysms. In small aneurysms EVAR was associated with excellent outcome. This finding may justify reappraisal of currently accepted management strategies.     

Subdural hematoma after thoracoabdominal aortic aneurysm repair: an underreported complication of spinal fluid drainage?

OBJECTIVE: Cerebrospinal fluid (CSF) drainage is a commonly used adjunct to thoracoabdominal aortic aneurysm (TAAA) repair that improves perioperative spinal cord perfusion and thereby decreases the incidence of paraplegia. To date, little data exist on possible complications, such as subdural hematoma caused by stretching and tearing of dural veins, should CSF drainage be excessive. We reviewed our experience with patients in whom postoperative subdural hematomas were detected. METHODS: The records of 230 patients who underwent TAAA repair at the Johns Hopkins Hospital between January 1992 and February 2001 were reviewed. RESULTS: Eight patients had subdural hematomas (3.5%). The four men and four women had a mean age of 60.6 years; two of these patients had a connective tissue disorder. All patients had lumbar drains placed before surgery, including one patient who underwent an emergency operation for rupture. Drains were set to allow drainage for CSF pressure greater than 5 cm H(2)O in all but one patient set for 10 cm H(2)O; spinal cooling was not performed in any patient. All drains were removed on the third postoperative day. In patients in whom subdural hematomas developed, the mean amount of CSF removed after surgery was 690 +/- 79 mL, which was significantly greater than the amount drained from patients in whom subdural hematomas did not develop (359 +/- 24 mL; P =.0013, Mann-Whitney U test). Six patients had postoperative subdural hematomas detected during hospitalization (mean postoperative day, 9.3; range, 2 to 16), and two patients were seen in delayed fashion after discharge from the hospital at 1.5 and 5 months. Four patients died of the subdural hematoma (50%); only one of these patients had neurosurgical intervention. All four survivors responded to neurosurgical intervention and are neurologically healthy. Two patients, both of whom were seen in delayed fashion, needed a lumbar blood patch. Multivariate logistic regression identified the volume of CSF drained as the only variable predictive of occurrence of subdural hematoma (P =.01). CONCLUSION: Subdural hematoma is an unusual and potentially catastrophic complication after TAAA repair. Prompt recognition and neurosurgical intervention is necessary for survival and recovery after acute presentation. Epidural placement of a blood patch is recommended if a chronic subdural hematoma is detected. Care should be taken to ensure that excessive CSF is not drained perioperatively, and higher (10 cm H(2)O) lumbar drain popoff pressures may be necessary together with meticulous monitoring of patient position and neurologic status.     

Endoleaks during follow-up after endovascular repair of abdominal aortic aneurysm. Are they all dangerous?

AIM: Development of endovascular abdominal aortic aneurysm repair (EVAR) has been accompanied by previously unencoutered complications. The most challenging but least understood of these complications is incomplete seal of the endovascular graft (endoleak), a phenomenon which has a variety of causes. An important consequence of endoleakage may be persistent pressurisation of the aneurysm sac, which may ultimately lead to post-EVAR rupture. METHODS: Data of 110 European centers were recorded in a central database (EUROSTAR). Patient, anatomic characteristics and operative and device details were correlated with the occurrence of different types of endoleaks. Outcome events during follow-up, notably expansion of the aneurysm, incidence of conversion to open repair and post-EVAR rupture were assessed in the different categories of endoleaks and in a group of patients without any endoleak. RESULTS: Type I and III endoleak were associated with an increased frequency of open conversions or risk of rupture of the aneurysm. Device-related endoleaks also correlated with an increased need for secondary interventions. These types of endoleak need to be treated without delay, and when no other possibilities are present, an open conversion to avert the risk of rupture should be considered. Endoleaks type II do not pose an indication for urgent treatment. However, they may not be harmless, as there was a frequent association with enlargement of aneurysm and reinterventions. CONCLUSION: Our findings suggest that more frequent surveillance examinations are indicated than in patients without collateral endoleak. The indication for intervention is primarily dictated by documented expansion of the aneurysm.     

Detection of postoperative pseudoaneurysms following abdominal aortic aneurysm repair in Behçet's disease by MRA

We report the development of two anastomotic pseudoaneurysms in a patient with Beh?et's disease eighteen months after abdominal aortic aneurysm repair. Major asymptomatic vascular complications should be suspected in patients with Beh?et's disease with a history of vascular surgery and treated expediently due to the risk of rupture. Magnetic resonance angiography, contrast-enhanced computed tomography or ultrasound scanning should be performed at least every 6 months after vascular surgery.     

Is abdominal aortic aneurysm repair appropriate in oxygen-dependent chronic obstructive pulmonary disease patients?

BACKGROUND: The life expectancy of patients with oxygen-dependent chronic obstructive pulmonary disease (COPD) is significantly reduced, but the risk of any intervention is considered prohibitive. However, severe COPD may increase the risk of abdominal aortic aneurysm (AAA) rupture. We reviewed our experience with AAA repair in oxygen-dependent patients to determine whether operative risk and expected long-term survival justify surgical intervention. METHODS: A retrospective review of 44 consecutive patients with oxygen-dependent COPD undergoing AAA repair over an 8-year period was performed. Information was recorded for survival, length of follow-up, patient age, medical comorbidities, pulmonary function tests, and operative approach. Survival data were analyzed by Kaplan-Meier curves and compared with published cohorts of oxygen-dependent patients and the natural history of untreated aneurysms. RESULTS: Twenty-four patients underwent endovascular aneurysm repair (EVAR), and 20 underwent open procedures (14 retroperitoneal and 6 transabdominal). The mean AAA diameter was 6.1 cm (range, 5-9.5 cm). The mean age was 71.4 years, and 82% of patients were male. Operative mortality was 0%. The mean length of stay was 11.2 days for open procedures and 4.3 days for EVAR (significantly longer than that for standard-risk patients). The mean survival time was 37.9 months (range, 2-91 months). Preoperative medical comorbidities, type of repair, and pulmonary function tests were not predictive of survival. Postoperative morbidity was significantly higher with open repair. Long term survival was comparable to historical series of the natural history of O2 dependent patients without AAA but better than untreated 6 cm AAA cohorts. At 42 months, almost 50% of patients in our study group were still alive, compared to 20% survival at 34 months for those with untreated 6 cm AAAs. CONCLUSIONS: It is reasonable to continue to offer AAA repair to home oxygen-dependent COPD patients who are ambulatory and medically optimized and who are without untreated coronary artery disease. Although EVAR may be the most suitable treatment for oxygen-dependent COPD patients, our results show that even open repair may be safely performed in this population, with acceptable results.     

Is diabetes a risk factor for patients undergoing open abdominal aortic aneurysm repair?

A number of studies have compared results after aortic procedures in diabetics vs nondiabetics but few have focused specifically on abdominal aortic aneurysm surgery. An analysis of prospective data was carried out in the Vascular Surgery Registry (Beth Israel Deaconess Medical Center, Boston, MA) and identified 421 patients (422 grafts) who underwent elective open repair of an abdominal aortic aneurysm between 1990 and 1999. The influence of diabetes mellitus on outcome was assessed by dividing the patients into two groups: 52 diabetic and 370 nondiabetic patients. Postoperative mortality was 1.7% overall (n = 7) and proportionally higher in the diabetic population, although this did not reach statistical significance (3.8% vs 1.4%, p = 0.19). However, cumulative survival at 1 year and 3 years was essentially identical for diabetic vs nondiabetic patients (91.0% vs 92.6% and 70.0% vs 73.5%, respectively) and did not diverge until 5 years after surgery (25.0% vs 50.9% respectively [p > 0.05]). Overall, major complications occurred in 11 diabetics (21.2%) vs 58 nondiabetics (15.7%, p = 0.32). Specific complications that were increased in the diabetic population included pancreatitis (5.8% vs 1.1%, p = 0.01) and pneumonia (11.5% vs 3.2%, p = 0.006). Notably, overall cardiac morbidity was not higher in patients with diabetes mellitus (1.9% vs 4.3%, p = 0.41). Our data suggest that after elective open abdominal aortic aneurysm repair, patients with diabetes mellitus may have a higher rate of certain complications when compared to patients without diabetes mellitus. These differences however, do not preclude the expectation of excellent results of open abdominal aortic aneurysm repair in patients with diabetes mellitus.