Lethal complications associated with nonrestrictive treatment of abdominal aortic aneurysms

Chronic complete thrombosis of abdominal aortic aneurysm: An unusual presentation of an unusual complication

Although mural thrombosis frequently accompanies aneurysmal disease, complete thrombosis is distinctly unusual complication of abdominal aortic aneurysm (AAA). A case study of a patient with chronic, asymptomatic complete thrombosis of a large juxtarenal AAA is presented along with a literature review and discussion of the potential secondary complications, mandating aggressive management of this condition. A 67-year-old man with multiple atherogenic risk factors and unattended complaints consistent with a recent episode of a transient right hemispheric ischemic attack was referred to our clinic with a diagnosis of a thrombosed AAA established by computed tomography. Duplex ultrasonography and aortography confirmed the referral diagnosis and also revealed near occlusion of the left internal carotid artery. The patient underwent a two-stage surgery, with preliminary left-sided carotid endarterectomy followed three days later by an aneurysmectomy and aortobifemoral reconstruction. He had an uncomplicated recovery and was discharged home on postoperative day 7, remaining asymptomatic at the 42-month follow-up. Complete thrombosis is an uncommon presentation of AAA and may be clinically silent. It is frequently associated with other manifestations of generalized atherosclerosis. Radical open repair yields durable result and is the preferred treatment modality.

Pressure measurements in closed aneurysmal sac during abdominal aortic aneurysm resection

PURPOSE

This study determined the relationship between closed aneurysmal sac pressure (ASP) and mean blood pressure (BP) during open abdominal aortic aneurysm (AAA) resection and evaluated the contribution of inferior mesenteric and lumbar artery blood flow to ASP after proximal and distal clamping.

METHODS

We measured ASP after proximal and distal clamping by placing an 18-gauge needle connected to a BP transducer into the excluded aneurysmal sac in 25 consecutive patients from April 1999 to August 2000. Simultaneous measurement of the mean systemic BP was also recorded. The ratio of ASP to mean BP in relation to the number of actively bleeding lumbar arteries (N-LA), diameter of the AAA (D-Cm), and volume of the thrombus in the AAA (Vol-TA) were recorded.

RESULTS

The mean ASP was 43.32 +/- 15.19 mm Hg, with an ASP to mean BP ratio of 0.47 +/- 0.15. The N-LA in the closed aneurysmal sac ranged from 0 to 6 (mean, 3.4 +/- 1.78). The D-Cm as determined by means of computed tomography (CT) scan of the aorta ranged from 5 to 8 cm in its largest anteroposterior/transverse diameter. The average Vol-TA was 6.15 +/- 4.49 mL. Inferior mesenteric artery blood flow contributed to ASP in three patients (12%). There was no correlation between ASP to mean BP ratios and the N-LA (P =.127), D-Cm (P =.882), or Vol-TA (P =.252).

CONCLUSION

Closed ASP and ASP ratios are highly variable and do not correlate with N-LA, D-Cm, or the Vol-TA.

Extra-anatomic arterial reconstruction with ligation of common iliac arteries and embolization of the aneurysm for the treatment of abdominal aortic aneurysms in high-risk patients

PURPOSE

The mortality of an unrepaired abdominal aortic aneurysm (AAA) generally exceeds the mortality associated with surgical repair. However, as our longevity increases, more frequently we see patients whose risk of surgical repair approximates the risk of rupture. We present an extra-anatomic bypass graft with complete aneurysm exclusion by iliac ligation and coil embolization of the aneurysm as an alternative for these high-risk patients.

METHODS

An extra-anatomic bypass graft, followed by bilateral iliac artery ligation (retroperitoneal approach) and complete coil embolization of the AAA, was performed in eight patients (mean age, 77 years) found to be at prohibitive operative risk because of multiple comorbidities (American Society of Anesthesiologists class IV). Most patients (5 of 8) were symptomatic on presentation with a mean AAA diameter of 7 cm (range, 6.7-9.5 cm). We repair approximately 30 infrarenal aneurysms per year electively at our institution.

RESULTS

All patients tolerated the surgical procedures. The average hospital stay was 8 days. All but two aneurysms demonstrated complete thrombosis by 48 hours. After 48 months there was no incidence of graft thrombosis, peripheral ischemia, visceral ischemia or thrombus infection. There was one perioperative death from aspiration pneumonia. Seventy-five percent (6 of 8) of patients have survived at least 1 year without surgical complications. No patient has had a ruptured aneurysm.

CONCLUSION

Combining an extra-anatomic bypass graft and complete exclusion of the AAA by ligation of the common iliac arteries and a coil embolization is an effective, less invasive treatment option for patients with AAA and prohibitive operative risk. We emphasize the need for complete embolization documented by decreased aneurysm size.

Midterm experience with the endovascular treatment of isolated iliac aneurysms

PURPOSE

This report describes our 5-year experience with the endovascular repair of isolated iliac aneurysms and pseudoaneurysms.

METHODS

Between June 1993 and July 1998, 40 isolated iliac aneurysms and pseudoaneurysms were treated with endovascular grafts in 39 patients. Thirty-seven aneurysms were treated with endovascular grafts composed of polytetrafluoroethylene grafts and balloon expandable stents, and the other three underwent repair with a polycarbonate urethane endoluminal graft.

RESULTS

All the patients underwent initially successful endovascular treatment of isolated iliac aneurysms and pseudoaneurysms and were followed from 1 to 51 months (mean, 18 months). The 4-year primary patency rate was 94.5% +/- 10%. The perioperative complications included one episode of distal embolization, an episode of colonic ischemia, five episodes of kinking or compression of the endovascular graft, and one early postoperative graft thrombosis. There was only one perioperative death in a patient whose aneurysm ruptured in the operating room just before endovascular repair. The median postoperative length of hospital stay was 3.0 +/- 1.3 days in this group of patients at moderate and high risk. The long-term complications included one graft thrombosis and two endoleaks. One small endoleak was followed until the patient died of unrelated causes, and the other one led to aneurysm rupture in the only patient temporarily lost to follow-up examination. This patient successfully underwent treatment in the standard open surgical fashion. To date, all the other aneurysms have remained stable or have decreased in size during the follow-up examinations with duplex or contrast-enhanced computed tomographic scans.

CONCLUSION

Endovascular repair of iliac aneurysms and pseudoaneurysms is a safe and effective technique with good midterm results in patients at standard and high risk. These grafts are particularly beneficial for patients with medical, surgical, or anatomic contraindications for open surgical repair.

Occluding aortic endoluminal stent graft combined with extra-anatomic axillofemoral bypass as alternative management of abdominal aortic aneurysms for patients at high risk with complex anatomic features: a preliminary report

PURPOSE

To describe an exclusion endoluminal technique for management of abdominal aortic aneurysms among high-risk patients with complex anatomic features.

METHODS

From January 1995 to December 1996, among 143 patients with infrarenal abdominal aortic aneurysm treated by means of endograft placement, 9 (6.3%) had complex aortic or aortoiliac morphologic features. For these patients, the endograft was delivered through a femoral cutdown in an occluding aortoiliac configuration. The contralateral iliac artery was occluded with an iliac endograft. Axillofemoral bypass grafting was performed. Computed tomographic scans were obtained regularly.

RESULTS

There was 1 postoperative death of severe arrhythmia. All aneurysms were found to be affected by thrombosis on immediately postoperative computed tomographic scans, except in 1 patient with a proximal leak, which was managed successfully with angiographic embolization. The mean follow-up time was 12 months. Aortic aneurysm diameter decreased from 2 mm at 6 months (2 patients) to 6 mm at 12 months (6 patients). All axillofemoral bypass grafts are patent.

CONCLUSIONS

Placement of an occluding endograft associated with axillofemoral bypass grafting is a good alternative for patients at high risk with complex anatomic features. Longer-term follow-up study is needed to evaluate this endoluminal technique.

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.

Complementary surgical/interventional techniques for nonresective management of "inoperable" aneurysms: a second look

Induced thrombosis ("nonresective" therapy) of aortic aneurysms by distal arterial ligation, coil/wire embolization, and extraanatomic bypass was devalued by anecdotal reports emerging during the mid-1980s. Nevertheless, we have recently found the technique to be life-saving in occasional cases and worth revisiting. Since 1990, standard aortic aneurysm repair has been performed in 231 patients (99.1% survival), endovascular aortic aneurysm repair in 6 patients (83.3% survival), and combined surgical/interventional "nonresective" repair of a variety of aneurysms in 10 patients (100% survival). Mean age of the group was 67.9 years. Repair was performed for aortoiliac aneurysms (4), common iliac aneurysms (3), internal iliac aneurysms (2), and a large proximal subclavian artery pseudoaneurysm (1). Four of the patients had been explored and declared to be "inoperable" (retroperitoneal fibrosis) prior to transfer to the Columbia-Presbyterian Medical Center. All patients survived. Aneurysm rupture has not occurred in any patient, but one patient with a presumably thrombosed subclavian pseudoaneurysm presented 26 months postcoil-induced thrombosis with progressive aneurysm enlargement due to incomplete aneurysm thrombosis and required repair using circulatory arrest. Eight of the patients remain alive (80%) at a mean follow-up of 40.3 months (range 14-88 months). Two patients died of malignancy (30 months) and cardiac disease (15 months). It is concluded that combined surgical/interventional techniques can be life-saving in the rare instances when conventional or endovascular aneurysm repair is not advisable but that complete aneurysm thrombosis is essential and occasionally difficult to achieve. Since small proximal portions of the aneurysm may remain patent and not be visualized on magnetic resonance imaging (MRI) or computed tomography (CT) scans, contrast angiographic documentation of complete aneurysm thrombosis is essential prior to hospital discharge and close follow-up is necessary to ascertain long-term adequacy of the repair. Incomplete thrombosis is suspected as a major factor in earlier reports of aneurysm rupture after seemingly successful nonresective therapy.

Transfemoral endovascular repair of iliac artery aneurysms

PURPOSE

This report evaluates the application of transfemoral endovascular repair of iliac artery aneurysms.

PATIENTS AND METHODS

Over a 20-month period, 11 patients with serious comorbid illnesses and a total of 14 iliac artery aneurysms were treated with endovascular grafts composed of polytetrafluoroethylene conduits combined with balloon expandable iliac artery stents (Palmaz). Nine right common, 3 left common, and 2 right internal iliac artery aneurysms were treated. The patients were men between 58 and 89 years of age (mean 72). Eight patients had isolated aneurysms and 3 had multiple iliac artery aneurysms.

RESULTS

Endovascular iliac grafts were successfully placed in all 11 patients. No procedural deaths occurred. Follow-up ranged from 3 to 21 months (mean 11). No acute or late graft thromboses occurred.

CONCLUSIONS

Transluminally placed endovascular stented grafts can be used to successfully exclude iliac artery aneurysms from the circulation while maintaining lower-extremity arterial perfusion. However, longer follow-up in more patients is necessary to confirm the durability of this technique.

A non-resective therapy for abdominal aortic aneurysm: intravascular thrombosis by dropping inflatable balloons

A case of subrenal abdominal aortic aneurysm treated by unipolar exclusion and axillobifemoral bypass is reported. The exclusion was performed by inserting inflatable balloons through a femoral access and obstructing the iliac arteries. This technique may be useful in poor-risk patients with a symptom-free aneurysm.

Results of an exclusion technique for treatment of abdominal aortic aneurysm

An exclusion technique for the treatment of abdominal aortic aneurysm was used in six patients considered to be at high operative risk mainly because of chronic pulmonary disease. There were no deaths or immediate major complications. Thrombosis of the aneurysm was achieved in four of the six patients. However, in three cases, repeated percutaneous embolization was required to produce thrombosis. One patient developed a secondary rupture of a persisting infrarenal sac resulting from a patent inferior mesenteric artery. This patient was successfully managed by ligature of the infrarenal portion of the abdominal aorta through a median laparotomy. This study emphasizes the limits and the risks of the exclusion technique.

Ligation and extraanatomic arterial reconstruction for the treatment of aneurysms of the abdominal aorta

PURPOSE

Since Blaisdell et al. first described axillobifemoral bypass and aortic exclusion to treat patients at high risk with abdominal aortic aneurysms in 1965, this approach has been controversial. To help define the appropriate application of this procedure, the recent experience of the authors was reviewed.

METHODS

Twenty-six patients underwent operation between March 1980 and August 1992. Mean age was 71 +/- 7 years. Average aneurysm diameter was 7.0 +/- 1.5 cm. Sixty-nine percent of the aneurysms were symptomatic; 21% were suprarenal. All patients had serious comorbid factors. All underwent axillobifemoral bypass with iliac artery ligation; the infrarenal aorta was also ligated in 62%.

RESULTS

There were two postoperative deaths (7.7%). One- and two-year survival rates were 59% and 38%, respectively. Three patients died of aneurysm rupture (11.5%); the aorta had not been ligated in two of these patients. The remaining late deaths were due to comorbid conditions. Extraanatomic bypass grafts thrombosed in five patients; no limbs were lost.

CONCLUSIONS

Axillobifemoral bypass without aortic ligation does not effectively reduce the risk of aneurysm rupture. However, axillobifemoral bypass with aortic ligation is an acceptable treatment for patients with severe medical problems and symptomatic, anatomically complicated, or large abdominal aortic aneurysms. Because the risk of aneurysm rupture is not completely eliminated, this procedure should be reserved for patients with high-risk aneurysms who would not tolerate direct aortic replacement.

Delayed rupture of an internal iliac artery aneurysm following proximal ligation for abdominal aortic aneurysm repair

This is a report of a patient presenting with a contained rupture of an internal iliac aneurysm following proximal ligation after abdominal aortic aneurysm repair three years earlier. The patient presented with a large pelvic mass with symptoms of urgency, frequency, dysuria, tenesmus and fevers associated with anemia. Following evacuation of the aneurysm and direct suture ligation of the distal branches of the internal iliac artery, the patient's aortic graft was covered with omentum which also filled the pelvic cavity. The importance of proximal and distal control of aneurysms and/or the importance of complete luminal control of internal iliac artery aneurysms is emphasized by this case.

Embolization of a thoracic aortic aneurysm; the straddling coil technique: technical note

Occlusion of a patent postligated aortic aneurysm was performed percutaneously with modified use of giant steel coils in a 50-year-old man. Steel coils were placed across the short, narrowed segment of the aorta. Successful thrombosis of entire aortic aneurysm was accomplished. No complications occurred.

Treatment options for aneurysms in high-risk patients

The increasing prevalence of aneurysms in an aging population bears with it increasing numbers of patients who are less than optimal candidates for resection. It is likely that the majority of such patients can undergo standard resection, either by referral to a center where the management of the elderly chronically ill is commonplace or by providing intensive preoperative metabolic, cardiac, pulmonary, and nutritional resuscitation. Such preoperative preparation might well include coronary revascularization or carotid endarterectomy. For the occasional patient in whom medical comorbidity is advanced and fixed, or in whom rapid aneurysm expansion or worsening symptoms mandate immediate management, yet operative risk for standard aneurysm resection seems inordinately high, several nonresective options have been identified and tested. Among these options, aneurysm exclusion appears to have significantly better results (in terms of lower rates of operative mortality and subsequent aneurysm rupture) than distal aneurysm ligature. A more recent technique, aneurysm bypass, may have potential but has not been tested for a long enough period, or by an adequate number of surgeons, to have established itself as a nonresective option. Clinical judgment, technical expertise, and a willingness to seek assistance and consultation remain the hallmarks of the optimal management of the patient with an abdominal aortic aneurysm.

Exclusion-bypass for aneurysms of the descending thoracic and thoracoabdominal aorta

From October 1973 to April 1985, 81 patients with aneurysms of the descending thoracic or thoracoabdominal aorta underwent surgery. Eight (10%) of these patients were treated by exclusion-bypass. The aneurysm was located in the descending aorta alone in five cases, and in the descending thoracic and thoracoabdominal aorta in three cases. In all cases, the proximal anastomosis of the bypass was performed on the ascending aorta. The site of the distal anastomosis was the supraceliac aorta in two cases, the infrarenal aorta in three cases and the iliac arteries in three other cases. Exclusion was bipolar, at each end of the aneurysm, in six cases, and unipolar, ie. proximal interruption only, in two cases. Two patients died during the first postoperative month, one of rupture of the distal portion of the aortic arch, the second, after onset of secondary paraplegia. There were no other spinal, cardiac or cerebral complications. One patient died three months postoperatively of intercurrent pulmonary infection. The five other surviving patients whose mean follow-up period is 48.1 +/- 25 months, are alive and enjoying good health. Resection and grafting as advocated by Crawford, is the usual treatment proposed for aneurysms of the descending thoracic and thoracoabdominal aorta. Exclusion-bypass may however be preferred in the following cases: elderly patients with compromised respiratory status, aneurysms of the descending thoracic aorta, either voluminous, of infectious origin or associated with aneurysm of the infrarenal abdominal aorta.

Coronary artery disease in patients with aortic aneurysm: a classification of 302 coronary angiograms and results of surgical management

In an attempt to reduce early and late mortality caused by myocardial infarction in patients with aortic aneurysms, coronary arteriography and, when indicated, myocardial revascularization were performed prior to elective aortic reconstruction in 302 patients with infrarenal (289) or thoracoabdominal (13) aortic aneurysms. Severe correctable coronary artery disease (CAD) was identified in 31% of the entire series, whereas severe inoperable CAD was seen in another 5%. Severe, correctable CAD was documented in 42% of patients suspected to have CAD by standard clinical criteria and in 19% of those in whom CAD was not suspected. The overall mortality for 89 cardiac and 227 infrarenal aortic surgical procedures was 4,4%. Fatal complications after infrarenal aneurysm resection occurred in only one (1.6%) of 61 patients who had had preliminary myocardial revascularization.

Transfemoral placement of intraluminal polyurethane prosthesis for abdominal aortic aneurysm

Because of the significant mortality associated with the conventional surgical approach to abdominal aortic aneurysms (AAA) in the high risk patients and in those with ruptured aneurysms, we have developed a new approach to this problem, intraluminal aneurysm exclusion. This was achieved by an intraluminal prosthesis which approximated the diameter of the aorta above and below the aneurysm and is inserted through the femoral artery. The prosthesis consisted of biomedical grade elastomeric polyurethane with a NITINOL and/or stainless steel frame and was designed in such a configuration that it could be compressed inside a 15 F catheter and then regain its original shape after being discharged inside the aorta. The polyurethane prosthesis tolerated static pressures in excess of 300 Torr. Aneurysmal aortas were created in three adult sheep using large knitted Dacron pathches (6 X 9 cm) sewn onto a longitudinal aortotomy. After 4-6 weeks, an intraluminal prosthesis was passed transfemorally to the location of the aortic aneurysm. Following satisfactory placement and expansion of the prosthesis, a laceration was produced in the aneurysmal wall. No bleeding developed, which confirmed the integrity of the prosthesis in excluding the aneurysm from the aorta proper. Pulsation in the iliac arteries indicated the presence of aortic blood flow through the prosthesis. Autopsy examination demonstrated directly that the prosthesis was open and that its two ends were fixed in the aorta above and below the aneurysm. The study has demonstrated that intraluminal AAA exclusion could be achieved with an intraluminal polyurethane prosthesis inserted through the femoral artery.

Total exclusion technique for the management of abdominal aortic aneurysms

A total exclusion and extraanatomic bypass method has been described for the treatment of abdominal aortic aneurysm. The technique is a one-stage procedure and consists of a right axillofemoral and femorofemoral bypass combined with ligation or plication of the inflow and outflow tracts of the abdominal aneurysm. Successful aneurysmal obliteration is demonstrable intraoperatively by simple palpation for the absence of pulsations. Our experience has affirmed this approach to be remarkably effective in 15 elderly, multiple-risk patients. There were no operative deaths, and morbidity had been low in this small series. The total exclusion technique presented compares favorably with all previously reported nonresective methods based on distal common iliac artery interruption, alone or in combination with injection of thrombotic agents. In particular, the problem of delayed aneurysmal rupture can be avoided with this technique. In view of the recently reported successful use of improved grafts in the axillofemoral position, we believe that the method just described can reliably be applied to high-risk, critically ill patients with abdominal aortic aneurysms.