The fate of the infrarenal aortic neck after open aneurysm surgery

PURPOSE: The long-term success of the endovascular repair of abdominal aortic aneurysms is dependent on the secure fixation of the stent graft at the proximal and distal attachment sites. A progressive dilatation of the infrarenal neck may jeopardize this success. The data regarding this issue are scarce. However, the long-term fate of the infrarenal neck can be studied in patients who have undergone open aneurysm surgery. This was the purpose of the present investigation. METHODS: Between January 1989 and December 1993, 64 patients underwent open repair of infrarenal abdominal aortic aneurysms. Of the 36 patients who were eligible for the study, 19 had preoperative computed tomography scans that were available. The 19 patients also underwent a new computed tomography scanning at a mean of 71 +/- 12 months after surgery. RESULTS: The mean preoperative aortic diameter was 25.4 +/- 3.7 mm at the infrarenal neck, 24.8 +/- 3.4 mm at the level of the renal arteries, and 26.7 +/- 3.0 mm at the level of the superior mesenteric artery (SMA). The mean aortic diameter increased at all of the 3 levels: +2.8 +/- 3.1 mm (P =.0014) at the infrarenal neck, +2.8 +/- 3.0 mm (P =.0013) at the level of the renal arteries, and +1.3 +/- 3.0 mm (P = .080) at the level of the SMA. The annual growth rate was 0.48 mm/y (P = .0023) at the infrarenal neck, 0.46 mm/y (P =.0010) at the level of the renal arteries, and 0.21 mm/y (P = .5811) at the level of the SMA. No correlation was found between the preoperative infrarenal neck diameter (r = .295, P = .2194), the preoperative aortic diameter at the level of the renal arteries (r = .302, P = .2088), and the preoperative aortic diameter at the level of the SMA (r = .314, P =. 2043) and the corresponding growth rates. The patients were stratified into 2 groups one with a small annual growth rate at the infrarenal neck (n = 11; 0.3 mm/y) and no differences in the preoperative infrarenal neck diameter or the clinical characteristics were found between the groups. CONCLUSION: This investigation shows an aortic dilatation of the infrarenal neck and of the aorta at the level of the renal arteries of approximately 0.5 mm annually after open aneurysm surgery. This dilatation raises concern regarding the long-term success after endovascular repair. The data also indicate that 2 populations might exist with regard to the annual growth rate of the infrarenal neck one with low growth rate and one with higher growth rate. This might be of interest for the future selection of patients for endovascular repair.     

Abdominal and thoracoabdominal aortic aneurysm

Most abdominal aortic aneurysms (AAA) and thoracoabdominal aortic aneurysms (TAAA) are asymptomatic and are found on physical exam or incidentally during radiological studies for other indications. These aneurysms are repaired primarily because their risk of rupture increases geometrically as the size exceeds 5 cm. The potential morbidity of intraoperative visceral and spinal ischemia involved with TAAA repair may be reduced with various adjunctive maneuvers.     

Cyanamide-induced granulocytopenia

BACKGROUND: The appropriate management of patients who are older than 80 years of age and who present with an abdominal aortic aneurysm (AAA) remains controversial. While it appears that elective repair can be performed safely, appropriate management of these patients in the emergency situation is unclear. The purpose of the present study was to examine the results obtained in treating this elderly group in the elective and emergency setting, by operation and conservative techniques at St George Hospital, Kogarah. METHODS: Between January 1987 and December 1994 85 patients older than 80 years of age were treated for AAA. These patients were divided into four groups: I, elective presentation/no surgery; II, elective presentation/elective surgical repair; III, emergency presentation/surgical repair; and IV, emergency presentation/conservative treatment. We examined age, sex, size of AAA, mode of presentation, type of treatment, length of survival and cause of death. RESULTS: The mean age of the total group (n = 85) of patients was 84 years (range: 80-94). The mean AAA diameter for this group was 5.6 cm (95% CI: 5.2-6 cm). The diameters for group I (n = 40), II (n = 22), III (n = 16) and IV (n = 7) were 4.9 cm (4.4-5.5, 95% CI), 5.7 (4.9-6.5 CI), 7.0 (6.1-7.7 CI) and 6.2 (5.2-7.2 CI), respectively. The median survival for groups I, II, III and IV was 18, 38.5, 0.25 and 0 months, respectively. Group II had a longer survival than any other group (P = 0.015), and group IV had a shorter survival than the total group (P = 0.001). However, the length of survival was no different for III versus IV (P = 0.146). Deaths in each group were due to the following reasons. I: cardiopulmonary events (14), rupture (3), malignancy/sepsis (3); II: cardiopulmonary events (3), rupture (thoracic aneurysm) (2), malignancy (I); III: rupture (10), malignancy (I); and (IV): rupture (6), malignancy (1). CONCLUSIONS: Elective surgical repair offers the best management option for AAA in patients older than 80 years of age. Death may still occur from progression of aneurysmal disease at other sites. An aggressive surgical approach to the management of haemodynamically unstable patients in this age group is of questionable benefit.     

Topical anesthesia: Proxymetacaine versus Amethocaine for clear corneal phacoemulsification

BACKGROUND: The risk of rupture of large abdominal aortic aneurysms (AAAs) remains uncertain. This study aimed to provide data to help decide whether or not to operate on high-risk patients. METHODS: Clinicians were asked to refer all patients with an AAA, even if unfit or elderly. One hundred and ninety-two patients with an intact AAA of 5 cm or greater in diameter were seen in 9 years; 59 had no elective operation and follow-up data were available for 57 at a minimum of 2 years. Initial AAA diameters were 5.0-5-9 cm (n=25) and 6.0 cm or more (n=32). Survival curves were constructed for both groups. RESULTS: At the end of the study 50 of 57 patients had died. Median survival was 18 (range 1-90) months. Twenty (35 per cent) suffered rupture at a median interval of 18 (range 1-38) months. The risk of rupture within 3 years was 28 (95 per cent confidence interval 12-49) per cent for 5.0-5.9-cm AAAs and 41 (24-59) per cent for AAAs of 6 cm or greater. In 133 elective AAA operations in fit patients the 30-day mortality rate was 3 per cent. CONCLUSION: The risk of rupture within 3 years of diagnosis of an AAA of 5 cm or greater exceeds the expected operative mortality rate for fit patients. However, the majority of patients unfit for surgery died from other causes, and only a few would have benefited from aneurysm repair.     

Expansion pattern and risk of rupture of abdominal aortic aneurysms that were not operated on

OBJECTIVE: To analyse the outcome of selective management of patients with abdominal aortic aneurysms, the expansion patterns of the aneurysms, and the factors that influenced the rate of rupture. DESIGN: Retrospective study. SETTING: Malm? General Hospital, Lund University, Malm?, Sweden. SUBJECTS: 155 patients (96 men and 59 women) with abdominal aortic aneurysms who were not selected for operation for whatever reason were included in the study immediately after their first ultrasound scan. MAIN OUTCOME MEASURES: Mortality, expansion rate (mm/year) measured on ultrasound scan, and rate of rupture of aneurysm. RESULTS: Median aneurysmal diameter was 40 mm (range 20-80), and length (n = 106) 70 (range 28-140). The patients were followed up for a median of 3.4 years (range 0-10.2). A total of 107 patients died and in 21 the aneurysms ruptured (4 were operated on and survived). Thirteen patients were re-evaluated and operated on electively. Ultrasonography was repeated in 98 patients, the median expansion rates (mm/year) were 3.1 (diameter) and 1.9 (length). There was a significant linear relationship between initial size (diameter and length) and rate of expansion of diameter. The risk of rupture was greater in larger aneurysms that were expanding more quickly. The cumulative mortality was not affected by the 21 aneurysms that ruptured. CONCLUSION: Selective management of patients with aortic aneurysms is justified.     

A prospective study to define the optimum rescreening interval for small abdominal aortic aneurysm

A prospective study of 99 patients with small abdominal aortic aneurysms was undertaken using serial ultrasound to assess the optimum screening interval. Fifty-three patients had aneurysms measuring 2.5-3.9 cm and 46 patients aneurysms of 4.0-4.9 cm. Aneurysms measuring 2.5-3.9 cm were screened annually and those > 4.0 cm every 6 months. There were eight deaths in the 2.5-3.9 cm group, none attributable to a ruptured aneurysm and five patients have had their aneurysm repaired. Nine patients died in the 4.0-4.9 cm group, one with a ruptured aneurysm measuring 5.6 cm at her previous screening visit and who was unfit for operation. No other patient had an aneurysm which ruptured between scans. There were seven elective repairs in this group. No patient died following elective operation in either group. The mean growth rate of aneurysms in the 2.5-3.9 cm group was 2.2 mm in the first year, 2.8 mm in the second and 1.8 mm in the third. Corresponding growth rates in the 4.0-4.9 cm group were 2.7 mm, 4.2 mm and 2.2 mm. This study supports a policy of annual screening for aneurysms measuring 2.5-3.9 cm and 6-monthly screening for those > or = 4.0 cm.     

Severe muscle weakness secondary to paraneoplastic hypophosphatemia in neuroblastoma

OBJECTIVES: To evaluate the influence of the use of a bypass on the results of thoracoabdominal aortic aneurysm surgery. METHODS: The results of the repair of 224 thoracoabdominal aortic aneurysms operated upon between 1981 and the end of 1996 were evaluated retrospectively. In 122 cases we used simple cross-clamping (clamp and sew technique) and in 102 cases a left heart bypass (atrio-femoral or aorto-femoral) was the preferred method. Except for the use of cerebrospinal fluid drainage over the last years, the methods of spinal protection were the same in both groups. Renal protection was also identical in both groups. All aneurysms were repaired using the inlay technique. RESULTS: Hospital mortality was 11.2%: 14.7% in cross-clamp group versus 6.8% in the bypass group (p = 0.04). Postoperative dialysis was necessary in 9.8%: 12.7% in the cross-clamp group versus 6.8% in the bypass group (p = 0.108). Paraplegia occurred in 8.4%: 7.4% in the cross-clamp group versus 9.8% in the bypass group (p = 0.517). Using the highly predictive model of Acher, there would have been 33% spinal cord lesions in the bypass group. CONCLUSIONS: Hospital mortality, postoperative dialysis and postoperative spinal cord problems are lowered by the use of a bypass during the repair of thoracoabdominal aortic aneurysms. These results evidence that the use of a bypass is indicated in this complex operation.     

Popliteal aneurysm: surgical treatment is mandatory before complications occur

Between 1972 and 1995, surgical repair was undertaken for 94 popliteal aneurysms diagnosed in 71 patients (69 men and 2 women) with a mean age of 66 years. Ninety-one femoropopliteal bypasses, 2 lumbar sympathectomies and one primary amputation were performed. Postoperative results of 28 elective bypasses performed for asymptomatic aneurysms (AA) were compared with 63 revascularisations needed for symptomatic aneurysms (SA) secondary to thrombosis (31%), embolization (30%), venous or nerve compression (13%), or rupture (2.1%). Occlusion of at least one tibial vessel was documented angiographically in 40% of the asymptomatic aneurysms and in 80% of the symptomatic aneurysms. No significant difference was observed between 5-year graft-patency of asymptomatic aneurysms (64%, mean followup 30 months +/- 37.2) and symptomatic aneurysms (50%, mean followup 39 months +/- 40.9). Furthermore, 5-year graft patency was not influenced by the number of patent tibial vessels in either of these populations. No statistically significant difference between these two groups was observed with respect to morbidity (AA: 10.7%, SA: 19%), or early reintervention (AA: 7.1%, SA: 9.5%). However, 12 secondary amputations were needed, all of which were performed after repair of a symptomatic aneurysm (19%, p < 0.05). No postoperative mortality was observed after an elective bypass while 3 patients (4.8%) with symptomatic aneurysms died after an emergency surgery. Ischemic symptoms persisted in 56% of patients who were initially symptomatic. Surgical correction should therefore be performed once the diagnosis of a popliteal aneurysm has been established in order to prevent amputation and late sequelae.     

Tissue-separating capacity of growth cartilages

During 1989, 28 centers of the Association for Academic Research in Vascular Surgery (AURC) reported all cases involving patients with infrarenal abdominal aortic aneurysm (AAA) who reached the operating room alive. In a total series of 1107 procedures, 834 were performed electively. During 1993 and 1994, an effort was made to contact and, if possible re-examine the 794 (95.2%) patients who survived these elective procedures in order to establish survival curves, determine the causes of late death, and ascertain the predictive value for long-term survival of 628 perioperative variables recorded in 1989. Survival curves were calculated using the actuarial and Kaplan-Meier methods and compared with those obtained from national statistical records in a control population matched for age and sex. Variables with potential predictive value for late death were selected by univariate statistical analysis using either the chi2 or student t-test. In the group of 794 (92.5%) patients who survived elective AAA repair in 1989, survival rates were 93.9 +/- 1.8% at 1 year, 89.5 +/- 3.2% at 2 years, 83.5 +/- 3.2% at 3 years, 77.6 +/- 3.9% at 4 years, and 66.9 +/- 10.6% at 5 years. These rates were significantly lower than those observed in the control population. The mean annual death rate from cardiovascular disease was 1.8%, which was higher than in the control population matched for age and sex. Analysis using the Cox proportional risk model showed that the following variables were significant, independent predictors of late death: diameter of aneurysm (p < 0.02), choice of surgical approach in function of general status (p < 0.02), left ventricular insufficiency (p < 0.02), age (p < 0.02), carotid artery occlusion (p < 0.03), use of a surgical approach other than lobotomy (p < 0.04), cardiac arrhythmia (p < 0.04), duration of aortic clamping (p < 0.05), ECG evidence of myocardial ischemia (p < 0.05), abnormality at the upper limit of the aneurysm (p < 0.05), and advanced renal insufficiency (p < 0.05). Life expectancy in patients that undergo successful AAA repair is lower than in the general population. Although death is often unrelated to AAA or the repair procedure, the incidence of morbidity due to cardiovascular disease is higher than in a control population matched for age and sex. These findings suggest that better management of concurrent cardiovascular disease during the perioperative period and long-term follow-up holds the key to improving life expectancy in patients undergoing AAA repair.     

Natural history of abdominal aortic aneurysm detected by screening

A group of 88 patients with abdominal aortic dilation found in four ultrasonographic screening studies was followed prospectively by repeated ultrasonography. The initial aortic diameter ranged between 18 and 70 mm. In 19 patients (22 per cent) the aortic diameter exceeded 39 mm. The mean (s.e.m.) annual expansion rate of dilatations < 40 mm in diameter was 0.8 (1.2) mm; among those > or = 40 mm it was 3.3 (1.2) mm. The expansion rate increased with increasing initial diameter. Thirty-eight patients died; the overall mortality rate in the group was high in comparison with an age- and sex-matched population. One patient died after elective aneurysm surgery but none died from a ruptured aneurysm. In conclusion, in about 80 per cent of dilatations found in screening studies the aortic diameter was < 40 mm, with a low risk of rupture. One annual rescanning of an aneurysm < 35 mm in diameter is sufficient; a high overall mortality rate must be expected.     

Influence of birth weight on educational outcomes at age 9: the Miami site of the Infant Health and Development Program

BACKGROUND: The Quality of Surgical Care Project (QSCP) was established in May 1996, to evaluate surgical outcomes and where indicated, recommend changes to improve the quality of surgical care in Western Australia (WA). The purpose of this study is to establish benchmark standards in WA for operative mortality, 5-year survival and length of stay in all patients who were surgically treated for aneurysm of the abdominal aorta (AAA) in WA. METHODS: The WA Linked Database was used to link the morbidity and mortality records of all patients admitted and surgically treated for AAA in WA from 1985 to 1994. The linked chains of de-identified hospital morbidity and death records were selected using diagnostic and procedure codes pertaining to AAA. Three groups were separated for analysis: those admitted for rupture, those admitted for elective repair, and those who were admitted to hospital as an emergency without mention of rupture but who underwent repair for AAA. Independent analysis for gender and patients 80 years or more were included in the study. Patients were excluded from the study if they were less than 55 years of age. RESULTS: A total of 1475 cases (1257 males, 218 females) were identified. The mean age in elective cases was 70.4 years in males and 72.4 years in females, and for rupture the mean ages were 71.9 and 74.8 years, respectively. Median length of stay for males was 12 days for elective cases. Admission type or age did not significantly influence length of stay. Thirty-day mortality in males was 4.4% for elective repair and 36.7% for ruptured AAA and 5-year survival was 71.7 and 47.7%, respectively. The overall case fatality rate for ruptured AAA was 79.3% which included those cases who died from rupture without being admitted to hospital. CONCLUSIONS: These community-wide data provide a realistic measure of surgical performance for open repair of AAA. The outcomes for elective and rupture repair for AAA compare favourably with standards reported by international centres of excellence. They also support the use of this procedure in patients over 80 years of age with rupture. This information can be used for ongoing audit purposes and as a benchmark for the introduction of new treatment modalities.     

Improved prognosis of thoracic aortic aneurysms: a population-based study

CONTEXT: Managing thoracic aortic aneurysms identified incidentally by increased use of computed tomography, echocardiography, and magnetic resonance imaging is problematic, especially in the elderly. OBJECTIVE: To ascertain whether the previously reported poor prognosis for individuals with thoracic aortic aneurysms has changed with better medical therapies and improved surgical techniques that can now be applied to aneurysm management. DESIGN: Population-based cohort study. SETTING AND PATIENTS: All 133 patients with the diagnosis of degenerative thoracic aortic aneurysms among Olmsted County, Minnesota, residents between 1980 and 1994 compared with a previously reported cohort of similar patients between 1951 and 1980. MAIN OUTCOME MEASURES: The primary clinical end points were incidence, cumulative rupture risk, rupture risk as a function of aneurysm size, and survival. RESULTS: In contrast to abdominal aortic aneurysms, for which men are affected predominately, 51% of thoracic aortic aneurysms were identified in women who were considerably older at recognition than men (mean age, 75.9 vs 62.8 years, respectively; P= .01). The overall incidence rate of 10.4 per 100000 person-years (95% confidence interval [CI], 8.6-12.2) between 1980 and 1994 was more than 3-fold higher than the rate from 1951 to 1980. The cumulative risk of rupture was 20% after 5 years. Seventy-nine percent of ruptures occurred in women (P= .01). The 5-year risk of rupture as a function of aneurysm size at recognition was 0% for aneurysms less than 4 cm in diameter, 16% (95% CI, 4%-28%) for those 4 to 5.9 cm, and 31% (95% CI, 5%-56%) for aneurysms 6 cm or more. Overall 5-year survival improved to 56% (95% CI, 48%-66%) between 1980 and 1994 compared with only 19% between 1951 and 1980 (P<.01). CONCLUSIONS: In this population, elderly women represent an increasing portion of all patients with clinically recognized thoracic aortic aneurysms and constitute the majority of patients whose aneurysm eventually ruptures. Overall survival for thoracic aortic aneurysms has improved significantly in the past 15 years.     

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

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 = 0.0001), 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.     

Prevalence and risk of rupture of intracranial aneurysms: a systematic review

BACKGROUND AND PURPOSE: The estimates on the prevalence and the risk of rupture of intracranial saccular aneurysms vary widely between studies. We conducted a systematic review on prevalence and risk of rupture of intracranial aneurysms and classified the data according to study design, study population, and aneurysm characteristics. METHODS: We searched for studies published between 1955 and 1996 by means of a MEDLINE search and a cumulative review of the reference lists of all relevant publications. Two authors independently assessed eligibility of all studies and extracted data on study design and on numbers and characteristics of patients and aneurysms. RESULTS: For data on prevalence we found 23 studies, totalling 56,304 patients; 6685 (12%) of these patients were from 15 angiography studies. Prevalence was 0.4% (95% confidence interval, 0.4% to 0.5%) in retrospective autopsy studies, 3.6% (3.1 to 4.1) for prospective autopsy studies, 3.7% (3.0 to 4.4) in retrospective angiography studies, and 6.0% (5.3 to 6.8) in prospective angiography studies. For adults without specific risk factors, the prevalence was 2.3% (1.7 to 3.1); it tended to increase with age. The prevalence was higher in patients with autosomal dominant polycystic kidney disease (relative risk [RR], 4.4 [2.7 to 7.2]), a familial predisposition (RR, 4.0 [2.7 to 6.0]), or atherosclerosis (RR, 2.3 [1.7 to 3.1]). Only 8% (5 to 11) of the aneurysms were >10 mm. For the risk of rupture, we found nine studies, totalling 3907 patient-years. The overall risk per year was 1.9% (1.5 to 2.4); for aneurysms = 10 mm, the annual risk was 0.7% (0.5 to 1.0). The risk was higher in women (RR, 2.1[1.1 to 3.9]) and for aneurysms that were symptomatic (RR, 8.3 [4.0 to 17]), >10 mm (RR, 5.5 [3.3 to 9.4]), or in the posterior circulation (RR, 4.1 [1.5 to 11]). CONCLUSIONS: Data on prevalence and risk of rupture vary considerably according to study design, study population, and aneurysm characteristics. If all available evidence with inherent overestimation and underestimation is taken together, for adults without risk factors for subarachnoid hemorrhage, aneurysms are found in approximately 2%. The vast majority of these aneurysms are small (=10 mm) and have an annual risk of rupture of approximately 0.7%.     

Contemporary management of isolated iliac aneurysms

OBJECTIVE: Because isolated common iliac artery aneurysms are infrequent, are difficult to detect and treat, and have traditionally been associated with high operative mortality rates in reported series, we analyzed the outcomes of operative repair of 31 isolated common iliac artery aneurysms in 21 patients to ascertain morbidity and mortality rates with contemporary techniques of repair. METHODS: A retrospective review study was conducted in a university teaching hospital and a Department of Veterans Affairs Medical Center. Perioperative mortality and operative morbidity rates were examined in 17 men and four women with isolated common iliac artery aneurysms between 1984 and 1997. Ages ranged from 38 to 87 years (mean 69 +/- 8 years). Slightly more than half of the cases were symptomatic, with abdominal pain, neurologic, claudicative, genitourinary, or hemodynamic symptoms. One aneurysm had ruptured and one was infected. There was one iliac artery-iliac vein fistula. All aneurysms involved the common iliac artery. Coexistent unilateral or bilateral external iliac aneurysms were present in four patients; there were three accompanying internal iliac aneurysms. Overall, 52% of patients had unilateral aneurysms and 48% had bilateral aneurysms. Aneurysms ranged in maximal diameter from 2.5 to 12 cm (mean 5.6 +/- 2 cm). No patients were unavailable for follow-up, which averaged 5.5 years. RESULTS: Nineteen patients underwent direct operative repair of isolated iliac aneurysms. One patient had placement of an endoluminal covered stent graft; another patient at high risk had percutaneous placement of coils within the aneurysm to occlude it in conjunction with a femorofemoral bypass graft. Patients with bilateral aneurysms underwent aortoiliac or aortofemoral interposition grafts, whereas unilateral aneurysms were managed with local interposition grafts. There were no deaths in the perioperative period. Only one elective operation (5%) resulted in a significant complication, compartment syndrome requiring fasciotomy. The patient treated with the covered stent required femorofemoral bypass when the stent occluded 1 week after the operation. The patient treated with coil occlusion of a large common iliac aneurysm died 2 years later when the aneurysm ruptured. CONCLUSIONS: Isolated iliac artery aneurysms can be managed with much lower mortality and morbidity rates than aneurysm previously been reported by using a systematic operative approach. Percutaneous techniques may be less durable and effective than direct surgical repair.     

Reoperation after repair of type A and B dissecting aneurysm

BACKGROUND: In the late postoperative period after repair of an aortic dissection or dissecting aneurysm, reoperations may be required. The interval to reoperation, size and location of intimal tear, and results of reoperation were evaluated. METHODS: Between January 1982 and April 1997, 138 patients underwent surgery for Stanford type A (90 patients) or type B (48 patients) dissections of the aorta. The entire aorta was evaluated in postoperative follow-up by computed tomography and magnetic resonance imaging for 6 months to 15 years. Reoperations were performed in 14 (10.1%) patients with changes in the aneurysms at the site of the initial repair or in the distal aorta. Selective cerebral perfusion or retrograde cerebral perfusion with deep hypothermia was used in the repair of the ascending, arch, and distal arch aneurysms. Reoperations included aortic root reconstruction (n=3), resection of a pseudoaneurysm (n=1), and replacement of the ascending aorta (n=1), arch (n=5), descending aorta (n=2), thoracoabdominal aorta (n=1), or abdominal aorta (n=1). Secondary reoperations were performed in four patients (replacement of the arch [n=2], thoracoabdominal aorta and abdominal aorta). Consequently two patients had subtotal aortic replacements. The aneurysms were caused by an anastomotic leak, a new intimal tear following aortic cross-clamping, a second intimal tear in the distal arch or abdominal aorta, and Marfan syndrome. RESULTS: Two patients (2/18 11.1%) died of bleeding or low output syndrome. Two patients died of graft infection or prosthetic valve infection 3 months after surgery respectively. CONCLUSIONS: 1) The surgical results of reoperation for type A and B dissections were good. 2) Close postoperative follow-up of the patent false lumen in the entire aorta was necessary. 3) At the initial operation, total resection of the intimal tear in the aortic arch in low-risk patients reduced the risk of reoperation.     

Experimental creation of fusiform carotid artery aneurysms using vein grafts in rats

OBJECTIVE: We developed an in vivo model of growing fusiform aneurysms, using vein grafts to the rat carotid artery. This aneurysm model might demonstrate the pathological features of the development and growth of aneurysms to become giant aneurysms. METHODS: Placement of an interposed femoral vein graft to restore carotid artery flow was performed in Wistar rats. On Day 21, 75% of the grafts (mean diameter, 1.6 mm) were found to be dilated to resemble fusiform aneurysms (mean diameter, 5.82 mm), and 53% of these were giant. Quantitative analysis of the histological findings was performed using image-analyzing software. RESULTS: Histological findings were similar to those for human intracranial giant aneurysms. The average length of the initial grafts in the aneurysm group was 9.1+/-1.9 mm, and grafts were significantly longer and more tortuous than in the normal graft group (6.4+/-0.8 mm) (P = 0.01). Cross-sectional areas of the aneurysms (mean, 18.9 mm2) were significantly correlated with the following: 1) the area of intra-aneurysmal thrombosis (mean, 11.1 mm2) (P < 0.0001); 2) the number of intrathrombotic vascular channels (P = 0.005); and 3) the area of dissection, with hemorrhage, between the thrombus and the wall of the aneurysm (mean, 0.72 mm2) (P = 0.0013). Scanning electron microscopic examination showed evidence of endothelial damage associated with growth of the aneurysms. CONCLUSION: Recurrent hemorrhaging from intrathrombotic vascular channels caused dissection between the thrombus and the aneurysm wall, which led to growth of the experimental aneurysms to giant aneurysms. With this model, we demonstrated the growth mechanism of giant fusiform aneurysms.     

Comparative evaluation of cerebral aneurysms with selective arterially enhanced CT and DSA

The purpose of our study was to compare selective arterially enhanced spiral computed tomographs (ACT) with digital subtraction angiographies (DSA) in the presurgical assessment of cerebral aneurysms. A total of 24 aneurysms in 18 patients were explored in a prospective study by ACT and DSA, using an interactive combined CT-angiography suite. Dimensions of the aneurysm, its relation to the parent vessel, and the aneurysmal index were defined on DSA and on surface-shaded display of 3D reformatted images obtained from ACT. Results were correlated with surgical findings. Three aneurysms suspected on DSA were not confirmed by ACT. One fusiform aneurysm suspected on DSA corresponded to a sacciform aneurysm on ACT. Surgical findings confirmed 20 sacciform aneurysms. The aneurysmal index could be measured in all 20 cases of sacciform aneurysms on ACT and could not be determined with confidence in 55 % of the cases on DSA. DSA and ACT gave identical results in 35 % of cases. In 10 %, the index measured by ACT was superior to that determined by DSA for aneurysms which had a diameter of less than 3 mm. In conclusion, the combination of DSA and ACT improved the results of DSA alone. ACT is a reliable method to measure the aneurysmal index in aneurysms with a diameter superior to 3 mm.     

Diagnosis and treatment of abdominal aortic aneurysms

Abdominal aortic aneurysms occur in 5 to 7 percent of people over age 60 in the United States. An aneurysm is defined as a permanent localized dilatation of an artery, with an increase in diameter of greater than 1.5 times its normal diameter. Abdominal aortic aneurysms may be manifested by catastrophic rupture, signs of pressure on other viscera or an embolism originating in the aneurysmal wall, but most cases are asymptomatic. The diagnosis is often made by physical examination of the abdomen, which reveals a pulsatile mass left of the midline, between the xyphoid process and the umbilicus. The diagnosis may be confirmed by B-mode ultrasound. Ultrasound screening should be considered for individuals at risk for abdominal aortic aneurysms. This group includes individuals over age 60 who smoke, have hypertension or have vascular disease. Elective surgical intervention is indicated for most patients with abdominal aortic aneurysms greater than 5 cm in diameter to prevent rupture and death. Smaller abdominal aortic aneurysms should be monitored by regular ultrasound measurements. Screening and identification of abdominal aortic aneurysms by primary care physicians can have a significant impact on patient survival.     

Retroperitoneal approach for repair of inflammatory aortic aneurysms

Inflammatory aortic aneurysms (IAAs) are characterized by a markedly thickened aortic wall and dense perianeurysmal fibrosis. The presence of such inflammation and subsequent organ adherence makes surgical repair of IAAs more challenging than repair of simple atherosclerotic aneurysms. From March 1987 to June 1994, twelve patients underwent surgical repair of an IAA by a single surgeon. Ten patients were men (83%) and the mean age was 68.3 years (range 58 to 93 years). All patients except one were symptomatic with back or abdominal pain, yet none had evidence of aneurysm rupture at operation. Preoperatively 90% (9/10) of the patients had an elevated erythrocyte sedimentation rate (ESR), 100% (12/12) had a predictive CT scan, and all patients with aortic wall pathology specimens had their diagnosis confirmed. Six patients had a left flank retroperitoneal surgical approach, five had a transabdominal approach, and one had ligation and extra-anatomic reconstruction. The choice of repair technique was based on the degree and anatomic distribution of perianeurysmal fibrosis. The 30-day operative mortality rate was 0%. Mean follow-up was 56.3 months. Aortoduodenal fistula occurred in one patient 5 months after transperitoneal repair. Technical difficulties encountered during subsequent transperitoneal repairs led to the evolution of a policy in which the retroperitoneal approach was preferred in all patients with CT evidence of IAA. It is concluded that IAA represents a spectrum of retroperitoneal fibrosis and inflammation that is best treated surgically via a retroperitoneal approach.