Infected aortic aneurysms

Salmonella organisms have been responsible for half of the reported cases of infected aortic aneurysms, although other bacteria have been incriminated. This is the second reported case in which Campylobacter fetus subspecies fetus apparently infected an inflammatory aortic aneurysm. In this 70-year-old man the organism was isolated and treated prior to resection of the aneurysm and inline grafting. Specific antibiotic therapy was continued for 8 weeks postoperatively. Examination and CT scans obtained after 9 months of follow-up reveal no evidence of recurrent infection.     

Infected aortic aneurysms: CT diagnosis.

Infected aortic aneurysms are uncommon but important because they can lead to uncontrolled sepsis and/or aortic rupture. Symptoms are frequently minimal during the early stages and a high index of suspicion is essential to make the diagnosis. The surgical literature suggests that survival is markedly improved by a prompt diagnosis and aggressive surgical intervention. Our recent experience with 5 cases who underwent arteriography and/or computed tomography (CT) prior to surgery was reviewed and these diagnostic methods compared. Traditionally, arteriography has been considered indispensable in the evaluation of infected aortic aneurysms but the aneurysm lumen must reach a certain size before it can be detected and, even then, the extraluminal component may be underestimated. CT, with contrast enhancement, was more sensitive in the early stages of the disease and provided a more complete depiction of the anatomic abnormalities. Mural enhancement preceded the increase in the aortic lumen with disruption of aortic wall calcification. An earlier and more accurate diagnosis can be provided by CT than by angiography without the disadvantages of its invasiveness and cost.     

Infected aortic aneurysms: aggressive presentation, complicated early outcome, but durable results.

OBJECTIVE: Infected aortic aneurysms are rare, difficult to treat, and associated with significant morbidity. The purpose of this study was to review the management and results of patients with infected aortic aneurysms and identify clinical variables associated with poor outcome. METHODS: The clinical data and early and late outcomes of 43 patients treated for infected aortic aneurysms during a 25-year period (1976-2000) were reviewed. Variables were correlated with risk of aneurysm-related death and vascular complications, defined as organ or limb ischemia, graft infection or occlusion, and anastomotic or recurrent aneurysm. RESULTS: Infected aneurysms were infrarenal in only 40% of cases. Seventy percent of patients were immunocompromised hosts. Ninety-three percent had symptoms, and 53% had ruptured aneurysms. Surgical treatment was in situ aortic grafting (35) and extra-anatomic bypass (6). Operative mortality was 21% (9/42). Early vascular complications included ischemic colitis (3), anastomotic disruption (1), peripheral embolism (1), paraplegia (1), and monoparesis (1). Late vascular complications included graft infection (2), recurrent aneurysm (2), limb ischemia (1), and limb occlusion (1). Mean follow-up was 4.3 years. Cumulative survival rates at 1 year and 5 years were 82% and 50%, respectively, significantly lower than survival rates for the general population (96% and 81%) and for the noninfected aortic aneurysm cohort (91% and 69%) at same intervals. Rate of survival free of late graft-related complications was 90% at 1 year and 5 years, similar to that reported for patients who had repair of noninfected abdominal aortic aneurysms (97% and 92%). Variables associated with increased risk of aneurysm-related death included extensive periaortic infection, female sex, Staphylococcus aureus infection, aneurysm rupture, and suprarenal aneurysm location (P <.05). For risk of vascular complications, extensive periaortic infection, female sex, leukocytosis, and hemodynamic instability were positively associated (P <.05). CONCLUSION: Infected aortic aneurysms have an aggressive presentation and a complicated early outcome. However, late outcome is surprisingly favorable, with no aneurysm-related deaths and a low graft-related complication rate, similar to standard aneurysm repair. In situ aortic grafting is a safe and durable option in most patients.     

Complications in the endovascular repair of abdominal aortic aneurysms: a risk factor analysis.

OBJECTIVES: to identify risk factors for complications following endovascular repair of abdominal aortic aneurysms (AAAs). MATERIALS AND METHODS: endovascular AAA exclusion was attempted in 64 patients. Patient characteristics, anatomic features of the aneurysm, operative technical aspects, and the experience of the teams were correlated with mortality, occurrence of endoleak, and other complications. Perioperative complications were graded following the recommendations of the Ad Hoc Committee on reporting standards. For the assessment of correlation between risk factors and outcomes a logistic regression analysis was used. RESULTS: complications were observed in 43% of the procedures and were classified as mild (24%), moderate (55%) or severe (21%). American Society of Anaesthesiology (ASA) risk class 3 or 4, and advanced age were independent risk factors for perioperative death and complications. Adjuvant procedures or overstenting of the renal arteries with the uncovered part of the stent were not associated with increased risk of complications. Nevertheless, in four of 24 overstented renal orifices, a renal infarction or ischaemia of the kidney was observed on a postoperative CT scan. Advanced experience was associated with less complications, less endoleaks, and shorter operating time. CONCLUSIONS: high age and medical co-morbidity were associated with increased risk for perioperative complications and death. Additional perioperative procedures are usually well tolerated. With greater experience in endovascular AAA grafting the incidence of complications and endoleaks decreased.     

Infected aortic aneurysms. A changing entity.

Infected (mycotic) aortic aneurysms are infrequent and, without surgical intervention, usually lead to uncontrolled sepsis or catastrophic hemorrhage. Symptoms are frequently absent or non-specific during the early stages, and a high index of suspicion is essential to make the diagnosis. Surgery performed after rupture carries high morbidity and mortality rates. Bacterial endocarditis with streptococcus pyogenes was the most common cause of infected aortic aneurysm in the pre-antibiotic era. Today, arterial trauma due to iatrogenic manipulation and depressed immunocompetence have become more common risk factors. Staphylococcus aureus and Salmonella are the most frequent bacteria identified. The authors' recent experience in six patients with infected aortic aneurysms who underwent arteriography and computed tomography was reviewed and these diagnostic methods compared. Computed tomography was found to be more sensitive in the diagnosis of the early stages of the disease, allowing for follow-up by serial scans in a noninvasive and less costly manner. Successful treatment, in four of these patients, was accomplished by aneurysmal resection and extra-anatomic bypass or in situ prosthetic reconstruction. A higher clinical awareness of this disease, leading to early computed tomography evaluation and prompt surgical intervention under appropriate and intensive antibiotic therapy, appears to offer the best chance of survival in patients with this difficult condition.     

Endoleaks after endovascular graft treatment of aortic aneurysms: Classification,risk factors,and outcome

Purpose: Incomplete endovascular graft exclusion of an abdominal aortic aneurysm results in an endoleak. To better understand the pathogenesis, significance, and fate of endoleaks, we analyzed our experience with endovascular aneurysm repair. Methods:Between November 1992 and May 1997, 47 aneurysms were treated. In a phase I study, patients received either an endovascular aortoaortic graft (11) or an aortoiliac, femorofemoral graft (8). In phase II, procedures and grafts were modified to include aortofemoral, femorofemoral grafts (28) that were inserted with juxtarenal proximal stents, sutured endovascular distal anastomoses within the femoral artery, and hypogastric artery coil embolization. Endoleaks were detected by arteriogram, computed tomographic scan, or duplex ultrasound. Classification systems to describe anatomic, chronologic, and physiologic endoleak features were developed, and aortic characteristics were correlated with endoleak incidence. Results: Endoleaks were discovered in 11 phase I patients (58%) and only six phase II patients (21%; p < 0.05). Aneurysm neck lengths 2 cm or less increased the incidence of endoleaks (p < 0.05). Although not significant, aneurysms with patent side branches or severe neck calcification had a higher rate of endoleaks than those without these features (47% vs 29% and 57% vs 33%, respectively), and patients with iliac artery occlusive disease had a lower rate of endoleaks than those without occlusive disease (18% vs 42%). Endoleak classifications revealed that most endoleaks were immediate, without outflow, and persistent (71% each), proximal (59%), and had aortic inflow (88%). One patient with a persistent endoleak had aneurysm rupture and died. Conclusions: Endoleaks complicate a significant number of endovascular abdominal aortic aneurysm repairs and may permit aneurysm growth and rupture. The type of graft used, the technique of graft insertion, and aortic anatomic features all affect the rate of endoleaks. Anatomic, chronologic, and physiologic classifications can facilitate endoleak reporting and improve understanding of their pathogenesis, significance, and fate. (J Vasc Surg 1998;27:69-80.)     

Endovascular repair of abdominal aortic aneurysms: device-specific outcome

OBJECTIVES: Endovascular repair of abdominal aortic aneurysms, while advantageous because of its minimally invasive nature, falls short of achieving the long-term durability of traditional open surgical repair. Problems such as device migration, continued sac pressurization from endoleak, and graft limb thrombosis culminate in a high rate of secondary procedures and failure to protect against aneurysm rupture. While prior studies hint at a correlation between these postprocedural events and specific device design, a single comparative analysis that correlates device attributes with clinical outcome has not been performed. METHODS: Over 6 years ending in 2002, 703 patients underwent endovascular treatment of infrarenal abdominal aortic aneurysms. During this time, five devices were used, ie, Ancure, AneuRx, Excluder, Talent, and Zenith, and six device-specific groups were analyzed; the Zenith group was subdivided into those placed as part of the multicenter trial (Zenith-MCT) and those under a sponsor-investigator investigational device exemption trial (Zenith-SIT). Results were assessed with the Kaplan-Meier method for censored data, and the log-rank test was used to ascertain differences between device groups. RESULTS: While overall survival was diminished in the Zenith-SIT group (P =.046), risk for aneurysm-related death was similar in all groups (P =.336), averaging 2% or less at 12 months. Among the total cohort of patients, freedom from rupture was 98.7% +/- 0.9% at 24 months, without demonstrable differences between groups (P =.533). There were no statistically significant differences in rate of secondary procedures, conversion to open repair, or migration. There were, however, significant differences in risk for graft limb occlusion and rate of endoleak between groups. Limb occlusion occurred most often with Ancure devices (11% +/- 4.6% at 12 months, P =.009). Endoleak of any type was most common with Excluder devices (64% +/- 11% at 12 months, P =.003), a finding directly related to increased frequency of type II leaks in that group (58% +/- 11% at 12 months, P =.001). While there were no differences in frequency of type I or type III endoleak, a trend toward increased risk for microleak was observed with AneuRx devices (4.0% +/- 1.3%, P =.054), and more modular separations were observed with Zenith devices (3.5% +/- 2.3%, P =.032). Shrinkage at 12 months correlated with frequency of endoleak in the device groups, and was most common in the two Zenith groups (54% +/- 7.3% in the Zenith-MCT group and 56% +/- 7.8% in the Zenith-SIT group) and the Talent group (52% +/- 9.7%) and was least in the Excluder group (15% +/- 7.9% at 12 months, P <.001). By contrast, sac growth occurred most often in the Zenith-SIT group (13% +/- 4.5% at 12 months, P =.034), possibly as a result of the challenging aortoiliac anatomy frequently present in these patients. CONCLUSIONS: There are significant differences in frequency of limb occlusion and endoleak between groups with different endovascular devices. Knowledge of these and other differences is instructional in development of next-generation endovascular devices, incorporating design features linked to satisfactory outcome while abandoning those associated with device failure.     

Long-term outcome of operated inflammatory aortic aneurysms

Inflammatory aortic aneurysms (IAAs) represent a rare form of aortic aneurysms. Compared with atherosclerotic aneurysms, patients with IAA have an increased risk of perioperative and long-term morbidity. This retrospective clinical study analyzed the outcome after conventional and endovascular repair of IAAs. Patients treated for an abdominal IAA between January 1995 and November 2004 were included. Imaging (computed tomographic angiography or magnetic resonance angiography) was performed preoperatively and at the time of follow-up (mean 2.7 years). Transperitoneal open repair and endovascular aortic repair were the operative procedures used. Over 10 years, 40 patients were treated with conventional and 5 patients with endovascular repair. The in-hospital morbidity rate was 11.1% (five patients; four conventional, one endovascular). On 10 patients (47.6%), the retroperitoneal fibrosis was no longer detectable. After operative repair, the majority of cases presented with a distinct regression of inflammation. Endovascular treatment of IAA represents a feasible alternative procedure to open aortic repair.     

Retroperitoneal nonresective staple exclusion of abdominal aortic aneurysms: Clinical outcome and fate of the excluded abdominal aortic aneurysms

Purpose: The purpose of this article was to prospectively study analyses outcome after staple exclusion of abdominal aneurysms with specific follow-up of the excluded aneurysm. Whether these data may predict behavior of aneurysms excluded from the circulation by transluminal grafting procedures is also addressed.Methods: Staple exclusion of abdominal aneurysms with bypass via retroperitoneal incisions was performed in 100 consecutive patients undergoing elective procedures. Risk factors, clamp time, operative time, transfusions, length of stay, complications, platelets, fibrinogen, and fibrin split products were documented. Duplex imaging was performed quarterly for 1 year after exclusion and at least annually thereafter. Serial measurements of aneurysm size and evaluation for thrombosis was obtained.Results: Aneurysm size averaged 5.5 cm. Risk factors included history of smoking (54%), history of heart disease (51%), hypertension (41%), hyperlipidemia (34%), and chronic obstructive pulmonary disease (25%). Clamp time averaged 51 minutes. Forty-eight required no intraoperative transfusion, and 19 needed only autologous blood; the average 24-hour transfusion was 313 cc. Length of stay averaged 11 days, with a median of 8 days, and correlated with age, aneurysm size, and risk factors. The 30-day mortality rate was 4%. Death was associated with longer operative and anesthesia times and with age and risk factors. As calculated by life-table analysis to 5 years, 96.8% of aneurysms thrombosed. No aneurysm expanded, became symptomatic, nor ruptured. Perioperative platelet, fibrinogen, and fibrin split product assays show no evidence of disseminated intravascular coagulation or consumptive coagulopathy.Conclusions: Staple exclusion and bypass of abdominal aneurysms as described in this study is safe and effective. There has been neither aneurysm expansion nor rupture, and the technique reliably leads to thrombosis of aneurysms without coagulopathy. (J VASC SURG 1995;21:623-34.)     

Abdominal aortic aneurysms in aged patients: analysis of risk factors in non-ruptured cases

BACKGROUND AND METHODS: A retrospective analysis of 304 patients (274 males and 30 females) surgically treated for non-ruptured, infrarenal abdominal aortic aneurysm (AAA) to determine the relative contribution of preoperative, operative, and postoperative factors to mortality and to the development of postoperative complications. 1) Risk factors, hospital mortality and long-term survival rate were compared between patients aged 75 or older (- group I; n=79) and those under 75 years of age (group II; n=225). 2) These risk factors were subjected to univariate and multivariate analysis to determine their relative contribution to patient hospital mortality and to the development of major postoperative complications in aged patients. RESULTS: Maximum diameter of AAA, the prevalence of respiratory dysfunction, diabetes mellitus and the total volumes of intraoperative blood loss were significantly different between the two groups. A higher hospital mortality was noted in the aged patients (10.1% versus 3.1%, p<0.05). The majority of deaths in group I resulted from organ dysfunctions, especially involved with respiratory failure. The long term survival rate at 3 and 5 years was not different between operative survivors in the two groups. Incremental risk factors for hospital death in aged patients included the presence of symptomatic AAA, the maximum diameter of AAA, the postoperative development of myocardial infarction, respiratory complications and gastrointestinal bleeding. Operation time and the volumes of intraoperative blood loss significantly correlated with the postoperative development of respiratory failure, renal failure and multiple organ failure. CONCLUSIONS: 1) A higher operative mortality and higher prevalence of postoperative complications were noted in aged patients with AAA. 2) To reduce operation time and the volumes of intraoperative blood loss would be essential to improve surgical results of AAA in aged patients.     

Endovascular repair of abdominal aortic aneurysms: risk stratified outcomes

OBJECTIVE: The impact of co-morbid conditions on early and late clinical outcomes after endovascular treatment of abdominal aortic aneurysm (AAA) was assessed in concurrent cohorts of patients stratified with respect to risk for intervention. SUMMARY BACKGROUND DATA: As a minimally invasive strategy for the treatment of AAA, endovascular repair has been embraced with enthusiasm for all prospective patients who are suitable anatomical candidates because of the promise of achieving a durable result with a reduced risk of perioperative morbidity and mortality. METHODS: From April 1994 to March 2001, endovascular AAA repair was performed in 236 patients using commercially available systems. A subset of patients considered at increased risk for intervention (n = 123) were categorized, as such, based on a preexisting history of ischemic coronary artery disease, with documentation of myocardial infarction (60%) or congestive heart failure (35%), or due to the presence of chronic obstructive disease (21%), liver disease, or malignancy. RESULTS: Perioperative mortality (30-day) was 6.5% in the increased-risk patients as compared to 1.8% among those classified as low risk (P = NS). There was no difference between groups in age (74 +/- 9 years vs. 72 +/- 6 years; mean +/- SD), surgical time (235 +/- 95 minutes vs. 219 +/- 84 minutes), blood loss (457 +/- 432 mL vs. 351 +/- 273 mL), postoperative hospital stay (4.8 +/- 3.4 days vs. 4.0 +/- 3.9 days), or days in the ICU (1.3 +/- 1.8 days vs. 0.5 +/- 1.6 days). Patients at increased risk of intervention had larger aneurysms than low-risk patients (59 +/- 13 mm vs. 51 +/- 14 mm; P <.05). Stent grafts were successfully implanted in 116 (95%) increased-risk versus 107 (95%) low-risk patients (P = NS). Conversion rates to open operative repair were similar in increased-risk and low-risk groups at 3% and 5%, respectively. The initial endoleak rate was 22% versus 20%, based on the first CT performed (either at discharge or 1 month; P = NS). To date, increased-risk patients have been followed for 17.4 +/- 15 months and low-risk patients for 16.3 +/- 14 months. Kaplan-Meier analysis for cumulative patient survival demonstrated a reduced probability of survival among those patients initially classified as at increased risk for intervention (P <.05, Mantel-Cox test). Both cohorts had similar two-year primary and secondary clinical success rates of approximately 75% and 80%, respectively. CONCLUSIONS: Early and late clinical outcomes are comparable after endovascular repair of AAA, regardless of risk-stratification. Notably, 2 years after endovascular repair, at least one in five patients was classified as a clinical failure. Given the need for close life-long surveillance and the continued uncertainty associated with clinical outcome, caution is dictated in advocating endovascular treatment for the patient who is otherwise considered an ideal candidate for standard open surgical repair.     

Surgical outcome of acute type A aortic dissection: analysis of risk factors

BACKGROUND: The aim of this study was to assess the risk factors for the early and late outcome of the surgical treatment of acute type A aortic dissection. METHODS: From 1983 to 2000, a total of 130 patients underwent operation for acute type A aortic dissection. Extent of distal aortic resection included ascending aorta in 19 patients (15%), hemiarch in 29 (22%), and total arch in 82 (63%). In all, 31 preoperative and perioperative variables were analyzed using univariate and multiple logistic regression models for independent predictors of in-hospital mortality and risk of late reoperation. After excluding in-hospital deaths, risk factors for late death were analyzed by Cox proportional hazard analysis. RESULTS: In-hospital mortality was 19.2% (25 of 130 patients). Multivariable analysis indicated that renal/mesenteric ischemia and shock were independent predictors of in-hospital death. At 10 years, the actuarial survival rate including in-hospital mortality was 70.9% +/- 4.7%, and the reoperation event-free rate was 73.5% +/- 5.7%. Aortic valve resuspension was an independent predictor of proximal aortic reoperation, whereas nonresection of intimal tear and younger age were independent predictors for distal aortic reoperation. Chronic obstructive pulmonary disease was the only independent predictor for late death. CONCLUSIONS: Patients' preoperative dissection-related complications and comorbidities significantly affect early and late survival rates after surgical treatment of acute type A aortic dissection.     

Maximal aortic diameter affects outcome after endovascular repair of abdominal aortic aneurysms

Objective

The purpose of this study was to evaluate whether maximal aortic diameter affects outcome after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA).

Mortality and paraplegia after thoracoabdominal aortic aneurysm repair: a risk factor analysis

BACKGROUND: Recent recommendations regarding thoracoabdominal aortic aneurysm (TAAA) management have emphasized individualized treatment based on balancing a patient's calculated risk of rupture with their anticipated risk of postoperative death or paraplegia. The purpose of this study was to enhance this risk-benefit decision by providing contemporary results and determining which preoperative risk factors currently predict mortality and paraplegia after TAAA surgery. METHODS: Risk factor analyses based on data regarding 1,220 consecutive patients undergoing TAAA repair from 1986 through 1998 were performed using multiple logistic regression with step-wise model selection. RESULTS: The 30-day mortality rate was 4.8% (58 of 1,220) and the incidence of paraplegia was 4.6% (56 of 1,206). For elective cases, predictors of operative mortality included renal insufficiency (p = 0.0001), increasing age (p = 0.0005), symptomatic aneurysms (p = 0.0059), and extent II aneurysms (p = 0.0054). Extent II aneurysms (p = 0.0023) and diabetes (p = 0.0402) were predictors of paraplegia. CONCLUSIONS: These risk models may assist in decisions regarding elective TAAA operations. For patients who are acceptable candidates, contemporary surgical management provides favorable results.     

The pathogenesis shared between abdominal aortic aneurysms and intracranial aneurysms: a microarray analysis

Neurosurgical Review - Abdominal aortic aneurysms (AAAs) and intracranial saccular aneurysms (IAs) are the most common types of aneurysms. This study was to investigate the common pathogenesis...