Proximal clamping levels in abdominal aortic aneurysm surgery

In the surgical treatment of abdominal aortic aneurysm, the single proximal cross-clamp can be placed at 3 alternative aortic levels: infrarenal, hiatal, and thoracic. We performed this retrospective study to evaluate the advantages and disadvantages of the 3 main aortic clamping locations. Eighty patients presented at our institution with abdominal aortic aneurysms from March 1993 through May 1998. Fifty of these patients had intact aneurysms and underwent elective surgery, and 30 had ruptured aneurysms that necessitated emergency surgery. Proximal aortic clamping was applied at the infrarenal level in 24 patients (22 from the intact aneurysm group, 2 from the ruptured group), at the hiatal level in 34 patients (22 intact, 12 ruptured), and at the thoracic level (descending aorta) via a limited left lateral thoracotomy in 22 patients (6 intact, 16 ruptured). Early mortality rates (within 30 days) were 4% (2 of 50 patients) among patients with intact aneurysms and 40% (12 of 30 patients) among those with ruptured aneurysms. In the 2 patients from the intact aneurysm group, proximal aortic clamps were applied at the hiatal level. In the ruptured aneurysm group, proximal aortic clamps were placed at the thoracic level in 10 patients, the infrarenal level in 1, and the hiatal level in 1. According to our study, the clinical status of the patient and the degree of operative urgency--as determined by the extent of the aneurysm--generally dictate the proximal clamp location. Patients who present with aneurysmal rupture or hypovolemic shock benefit from thoracic clamping, because it restores the blood pressure and allows time to replace the volume deficit. Infrarenal placement is advantageous in patients with intact aneurysms if there is sufficient space for the clamp between the renal arteries and the aortic aneurysm. In patients with juxtarenal aneurysms, hiatal clamping enables safe and easy anastomosis to the healthy aorta. Clamping at this level also helps prevent late anastomotic aneurysm formation, which is frequently encountered after inadvertent anastomosis of the graft to a diseased portion of the aorta. Further studies are needed in order to confirm these results.     

A comparative study of iliac and abdominal aortic aneurysms.

BACKGROUND: The aim of the paper is to compare the epidemiology, risk factors and manifestations of iliac and abdominal aortic aneurysms. METHODS: Two studies were used: 1. 5,470 65-73-year-old men invited for screening for abdominal aortic aneurysms. 2. Review of all 350 patients operated on for central aneurysms in the county of Viborg, Denmark from 1989-1997. RESULTS: 4,176 attended for screening. One hundred and seventy (4.0%) had an abdominal aortic aneurysm. Twenty-one (0.56%) needed operation. The proportion of patients with common iliac aneurysms requiring surgery was 0.17%. The operative incidence of iliac aneurysm was 18.4 per million per year, and 92.4 per million per year were operated on for abdominal aortic aneurysm. The mean serum cholesterol level for isolated iliac aneurysm and combined aneurysms was significantly lower compared to isolated abdominal aortic aneurysm (p<0.05). Urological symptoms were present in 42% of cases with isolated iliac aneurysm, and 25% of combined aneurysms compared to 8% of isolated abdominal aortic aneurysms. Fifty-eight percent of the isolated iliac aneurysms were ruptured, as against 27% of the abdominal aortic aneurysms. The peri- and postoperative mortality was 57% in ruptured isolated iliac aneurysms, 47% in ruptured combined aneurysms, and 31% in ruptured isolated aortic aneurysms. CONCLUSIONS: Iliac aneurysms seem to be more underdiagnosed than abdominal aortic aneurysms, and are often diagnosed because of clinical manifestations, especially urological, or rupture. Iliac aneurysms seem more lethal than those of the abdominal aorta in cases of rupture.     

Aortenaneurysma und -dissektion

Aortic aneurysms and aortic dissection represent a significant health risk due to the demographic developments and current life styles. The mortality of ruptured aortic aneurysms is up to 80 % and the prevalence of aneurysms varies depending on the localization (thoracic or abdominal). Most commonly affected is the infrarenal abdominal aorta; however, there is evidence that the prevalence is diminishing but in contrast the incidence of thoracic aortic aneurysms is increasing. Aortic dissection is often fatal and is the most common acute aortic disease but the incidence is presumed to be underestimated. The pathogenesis of aortic aneurysms is manifold and is based on an interplay between degenerative, proteolytic and inflammatory processes. An aortic dissection arises from a tear in the intima which results in a separation of the aortic wall layers with infiltration of bleeding and the danger of aortic rupture. Various genetic disorders of connective tissue promote degeneration of the aortic media, most notably Marfan syndrome. Risk factors for aortic aneurysms and aortic dissection are nicotine abuse, arterial hypertension, age and male gender. Aortic aneurysms initially have an uneventful course and as a consequence are mostly discovered incidentally. The clinical course and symptoms of aortic dissection are very much dependent on the section of the aorta affected and the manifestations are manifold. Acute aortic dissection is in 80 % of cases first manifested as sudden extremely severe pain. The diagnostics and subsequent course control can be achieved by a variety of imaging procedures but the modality of choice is computed tomography.     

Diagnostic and surgical management of patients with aneurysms of the thoracic aorta with various causes. Echocardiography and contrast enhanced computed tomography in prophylactic replacement of the ascending aorta

Sixty eight patients with aneurysms of the thoracic aorta were studied. Forty one had aortic dissection, 24 had dilatation only, and three had transverse aortic rupture. Sixteen had Marfan's syndrome; 17 had hypertension; and in eight there were other causal factors. In 17 the cause of the aneurysm was unknown. Histological examination did not help to establish the cause of aneurysm. Echocardiography failed to detect dissection of the ascending aorta in four (21%) out of 19 cases studied. The mortality rate in the whole series was 26%. Early (operative and hospital) and late deaths occurred in 20% and 6% of patients respectively. The early mortality rate was 40% in the 24 emergency cases of dissection of the ascending aorta, 9% in patients operated on for dilatation of the ascending and transverse aorta without dissection, and 8% in patients with chronic dissection of the ascending aorta who had elective operation. Early and late mortality rates were no higher in patients with Marfan's disease than in any of the other groups. It is suggested that contrast enhanced computer tomography should be performed in all patients with pronounced aortic root dilatation and in patients with Marfan's disease with symptoms which suggest dissection, even if they have only slight aortic root dilatation. Preventive replacement of the ascending aorta should be considered in more patients to reduce the number of emergency operations, in which the mortality rate is high. There is no definite limit of aortic root dilatation above which preventive replacement of the ascending aorta should be routinely considered.     

Diagnostic and surgical management of patients with aneurysms of the thoracic aorta with various causes. Echocardiography and contrast enhanced computed tomography in prophylactic replacement of the ascending aorta.

Sixty eight patients with aneurysms of the thoracic aorta were studied. Forty one had aortic dissection, 24 had dilatation only, and three had transverse aortic rupture. Sixteen had Marfan's syndrome; 17 had hypertension; and in eight there were other causal factors. In 17 the cause of the aneurysm was unknown. Histological examination did not help to establish the cause of aneurysm. Echocardiography failed to detect dissection of the ascending aorta in four (21%) out of 19 cases studied. The mortality rate in the whole series was 26%. Early (operative and hospital) and late deaths occurred in 20% and 6% of patients respectively. The early mortality rate was 40% in the 24 emergency cases of dissection of the ascending aorta, 9% in patients operated on for dilatation of the ascending and transverse aorta without dissection, and 8% in patients with chronic dissection of the ascending aorta who had elective operation. Early and late mortality rates were no higher in patients with Marfan's disease than in any of the other groups. It is suggested that contrast enhanced computer tomography should be performed in all patients with pronounced aortic root dilatation and in patients with Marfan's disease with symptoms which suggest dissection, even if they have only slight aortic root dilatation. Preventive replacement of the ascending aorta should be considered in more patients to reduce the number of emergency operations, in which the mortality rate is high. There is no definite limit of aortic root dilatation above which preventive replacement of the ascending aorta should be routinely considered.     

Modern trends in the management of aortic aneurysms. Review of 450 cases experienced

Treatment of various aortic aneurysms in 450 cases experienced during the past 25 years was analysed. One hundred and five patients were treated with survival rate of 80.2% in the thoracic aortic aneurysm group, 65 patients with survival rate of 76.9% in the dissected aneurysm of the aorta group, 175 patients with survival rate of 93.1% in the nonruptured abdominal aortic aneurysm group and 37 patients with survival rate of 75.7% in the ruptured abdominal aortic aneurysm group. From 1981 to the present time, considerable improvement of the operative results has been achieved with refinement of cardiovascular adjunctive techniques and operative procedures with careful management of the patients. Survival rates are now reached to 88.7% in the thoracic aortic aneurysm, 81.0% in the dissected aneurysm, 100% in the nonruptured abdominal aortic aneurysm and 81.2% in the ruptured abdominal aortic aneurysm. From the careful analyses of the results, prompt diagnosis, distinct treatment policy, strict operative indication and better surgical procedure are considered to have contributed to these excellent operative results.     

Fortuitous rupture of aortic aneurysm: A catastrophic event affording time for surgical cure

The rupture of an aortic aneurysm is generally a fatal event, but occasionally the rupture will occur into an adjacent vascular structure, thereby preventing exsanguination and affording temporary survival. Three cases are presented illustrating the fortuitous nature of the rupture of an aortic aneurysm into a vascular structure. The first patient had an atherosclerotic abdominal aortic aneurysm that ruptured into the inferior vena cava and was successfully repaired. The second case demonstrates the formation of a fistula from the aorta to the left pulmonary artery in a patient with a syphilitic thoracic aortic aneurysm. In the third patient a dissecting aneurysm of the aortic root that communicated with the right ventricle after coronary bypass surgery was successfully repaired. Rarely, aortic aneurysms will rupture fortuitously into vascular capacitance structures. These three cases emphasize the need for early accurate diagnosis and the institution of appropriate surgical measures.     

Surgical and medical treatments of true and dissecting aortic aneurysm in cases over 65 years old

Ninety-one patients with true and dissecting aortic aneurysm were reviewed. They ranged in age from 65 to 87 years (mean 71 years). Forty-eight patients were diagnosed with abdominal aortic aneurysm, 21 patients with thoracic aortic aneurysm and 22 patients with dissecting aortic aneurysm. They were divided into 2 categories, surgical group and non-surgical, and the prognoses of the 2 groups were compared. The average age of surgically treated cases was significantly younger than that of non-surgical cases. This study suggests that elective operation should be considered for abdominal aortic aneurysms because of the high risk of late rupture. In older patients with thoracic aortic aneurysm, the prognosis was better in surgically treated patients than in those not treated. However, the surgical mortality rate of elective operation was high. The surgical mortality rate of older patients with dissecting aortic aneurysm was not satisfactory, and medical treatment which decreases blood pressure should be considered first. All patients classified as Stanford type A should be operated on if possible.     

Incidence and clinical aspects of aneurysm rupture in the abdominal aorta]

On the basis of the section material of 25 years in Tartu a significant increase of the frequency of arteriosclerotic aneurysms of the aorta, especially of the abdominal aorta and its ruptures, could be established. At the same time the appearance of luetic aortic aneurysms decreased. Due to its variable symptomatology the diagnosis of the rupture of an aneurysm of the abdominal aorta is often not exactly diagnosed by the physician who is first in charge of the case. On the basis of a clinical material of 21 post-mortem examinations the diagnostics of the rupture of the aneurysm of the abdominal aorta is discussed, and the most important symptoms are emphasized. It is emphasized that an aneurysms of the abdominal aorta shall be recognized in every case allready before its rupture as the prognosis of the operation is relatively good in this stage. Since it must be reckoned with a continuous increase of the frequency of the arteriosclerotic lesions of the aorta the physician shall, too, always think of an aneurysm of the abdominal aorta when uncertain complaints of the abdomen and the back are present.     

Screening, diagnosis and advances in aortic aneurysm surgery

BACKGROUND: Aortic aneurysms are common in the elderly and a frequent cause of sudden death. As elective aneurysm repair has a mortality drastically lower than that associated with rupture, the emphasis must be on early detection and repair free from complications. Recent advances include ultrasound screening for asymptomatic abdominal aortic aneurysm (AAA) and clinical trials on the size of AAA that require repair. Pre-operative assessment, management of cardiac risk, autologous blood transfusion strategies, and endovascular stent graft technology to avoid major open surgery are all issues to be addressed. METHODS: Following a computerized Medline search for publications on the detection and treatment of abdominal and thoracic aortic aneurysm, the publications identified were then read and the references within those publications examined for further publications on this topic. We have reviewed these publications without attempting a meta-analysis. RESULTS: Randomized population studies have addressed ultrasound screening for AAA. Attendance for screening was good and AAA detection inexpensive. Screening men from 65 years reduces the mortality from rupture and is cost-effective. Open thoracic and abdominal aneurysm repair has a mortality of around 8%, with myocardial infarction being a frequent cause of death. Pre-operative reduction of cardiac risk by cardiac investigations and beta-blockade may reduce this mortality. Autologous transfusion techniques such as acute normovolaemic haemodilution and interoperative cell salvage reduce the need for allogeneic blood and the complications associated with open surgery. Minimally invasive endovascular repair is now possible for 40% of the AAA and an increasing proportion of thoracic aneurysms. CONCLUSIONS: The combination of screening, reduced pre-operative risk, and new minimally invasive techniques extends aortic aneurysm treatment into an increasingly elderly population. The combination of these techniques will reduce mortality from ruptured aortic aneurysm in the elderly and also reduce the stress associated with aneurysm surgery.     

Surgical techniques. Thoracoabdominal aorta

Patients presenting with impending rupture of a thoracoabdominal aortic aneurysm require emergency operative repair. To prevent rupture and its associated mortality, elective repair of thoracoabdominal aortic aneurysms exceeding 5.5 cm to 6.0 cm in diameter is recommended in patients with adequate physiologic reserve. Similarly, surgery should be considered for patients with smaller symptomatic aneurysms. Atypical symptoms have been associated with rupture, therefore, they require thorough evaluation. Whether the aortic conditions are caused by medial degenerative disease or chronic aortic dissection, surgical techniques allow for graft repair of thoracoabdominal aortic aneurysms with low mortality and morbidity rates. Although surgery is usually avoided in patients with acute distal aortic dissection, operative intervention is occasionally required when complications develop. Patients with acute aortic dissection complicated by impending rupture of the thoracoabdominal segment require graft repair to restore aortic integrity; although the mortality rate is acceptable, the incidence of postoperative paraplegia approaches 20% in this setting. For patients presenting with ischemic complications of acute distal aortic dissection, less-extensive surgical options have been effective in restoring perfusion. In experienced centers, overall operative survival rate following thoracoabdominal aortic surgery can exceed 92%. Retrospective data suggest that left heart bypass reduces the incidence of paraplegia following extensive thoracoabdominal aortic repairs. Although recent advances have led to improved outcomes, paraplegia continues to occur regardless of the strategy used. The prevention of spinal cord ischemia during thoracoabdominal aortic surgery, therefore, will remain a focus of controversy and investigation, just as it was more than 4 decades ago.     

Ruptured abdominal aortic aneurysms: experience with 70 cases

During the period 1965-1983, 270 patients underwent resection of abdominal aortic aneurysm. In 70 patients (26%) the aneurysm was ruptured. Overall hospital mortality of patients with ruptures was 34%. Five patients died before the graft could be completed. Common denominators associated with mortality were hypotension, renal failure, cardiac arrest, and postoperative hemorrhage. The average age over the first 10 years was 68, but subsequently, has risen gradually, with a corresponding increase in mortality despite improved surgical technique and postoperative care. Only with more widespread elective resections and earlier diagnosis of rupture followed by prompt operative management, can the outlook for patients with abdominal aortic aneurysm be improved.     

Chylothorax and chylous ascites following surgery of an inflammatory aortic aneurysm. Case report with review of the literature]

Chylous ascites complicating surgery on the abdominal aorta is infrequent: we report one case associated with right chylothorax, secondary to the surgical cure of an inflammatory aortic aneurysm. Surgery for aneurysms causes 81% of all chylous ascites caused by injuries to the intestinal lymphatics or to their recipients, the left latero-aortic lymph nodes or the cisterna chyli. Upper or extensive dissections of the retroperitoneal space and difficult dissection of ruptured or inflammatory aneurysms are the cisterna chyli. Upper or extensive dissections of the retroperitoneal space and difficult dissection of ruptured or inflammatory aneurysms are the major etiological factors. Stasis and fibrosis, then the rupture of the lymphatics into the aneurysmal wall were described during inflammatory aneurysm: this lymphatic etiology might explain the inflammatory character of these aneurysms and entail a risk of lymphoperitoneal fistula when laying the aneurysmal wall flat. An early diagnosis must be established with paracentesis before any compressive, metabolic, immunological or septic complications occur. Continuous parenteral feeding and selective paracenteses dry out 80% of the postoperative chylous ascites. If the ascites persists after 4 to 6 week's conservative treatment, a peritoneojugular derivation or a direct lymphostasis may be contemplated, according to the patient's condition.     

Aneurysms of the abdominal aorta in patients 80 and over years of age. Long term results

During a thirteen years period 29 patients 80 years of age and older, underwent surgical procedure for abdominal aortic aneurysm. There were 9 elective aortic reconstructions and 20 ruptured abdominal aortic aneurysms (AAA) repairs. Perioperative mortality after elective AAA resection was 33% vs 50% after ruptured AAA (a postoperative period of 30 days was considered). Comparison of survival following aortic reconstruction in 14 patients with survival of general population matched for age, sex and race, is not significant.     

Aneurysms of the aorta a consideration of pre- and postoperative medical management

The mortality following excision of aneurysms of the thoracic and abdominal aorta has been acceptably low and forms a sharp contrast with the mortality figures of unoperated series. Over 2,500 aneurysms of various types have been resected by the surgical group at the Baylor University College of Medicine. The mortality rate for resection of abdominal aneurysms is about 9 per cent over-all, a figure which includes those with and without associated heart disease and also includes those which had ruptured at the time of admission. The mortality rate for descending thoracic aneurysms is 20 per cent and that for all thoracic aneurysms about 26 per cent. A 5 year survival figure of patients after abdominal aneurysmectomy was 58 per cent contrasted with 9 per cent in the nonoperated series of Estes and Wright. An analysis of 179 patients with dissecting aneurysms disclosed an operative mortality of 21 per cent. When the dissection began beyond the origin of the left subclavian, the operative mortality among the 94 patients operated upon in the past 5 years was only 12 per cent.

Despite the high incidence of hypertensive disease, ischemic heart disease and associated cardiorenal abnormalities, most patients can be carried safely through surgery. There are virtually no late complications which are unique to this group of patients. In order that the operative and postoperative course may be smooth as possible, careful attention must be given to the possible presence of any abnormality of cerebrovascular, cardiopulmonary, renal and hepatic function. Associated disease such as occlusive disease of arteries supplying the lower extremities, hiatal hernia, cholelithiasis should be searched for in order that they may be corrected at the time of the aneurysmectomy if the operative approach permits. The cardiologist or internist plays a vital role in preoperative work-up as well as the operative and postoperative periods and it is of fundamental importance that he understand the problems related to each of these phases.     

Fibromuscular dysplasia of the aorta presenting as multiple recurrent thoracic aneurysms

A 17-year-old boy, who had undergone resection of aortic coarctation with a large saccular aneurysm 10 years previously, developed recurrent aneurysms above and below the site of a Gore-Tex interposition graft. These were resected using femoral-femoral bypass, and the upper thoracic aorta was replaced with a Hemashield Dacron tube. Histology of the aorta showed fibromuscular dysplasia. In addition to aortic dissection and aortic rupture, such patients may be at risk of forming further aneurysms.Presented at the 38th Annual World Congress, International College of Angiology, Cologne, Germany, June 1996     

Endovascular repair of a ruptured descending thoracic aortic aneurysm

Endovascular aneurysm repair has considerable potential advantages over the surgical approach as a treatment for thoracic aortic rupture, in part because open surgical repair of ruptured thoracic aortic aneurysms is associated with high mortality and morbidity rates. We describe the successful endovascular deployment of stent-grafts to repair a contained rupture of a descending thoracic aortic aneurysm in an 86-year-old man whose comorbidities prohibited surgery. Two months after the procedure, magnetic resonance angiography showed a patent stent-graft, a patent left subclavian artery, and complete exclusion of the aneurysm.     

Quality of Life after Replacement of the Ascending Aorta in Patients with True Aneurysms

True aneurysms of the ascending aorta often remain undetected, yet their sequelae carry a high rate of mortality and morbidity. The operative risk of nonemergent replacement of the ascending aorta is low. It is important to consider quality of life in determining the most appropriate treatment for patients who have aneurysms but have not yet experienced major complications.From January 1999 to December 2003, 134 consecutive patients underwent replacement of a dilated ascending aorta at our center. Another 124 patients with acute or chronic aortic dissections, aortic rupture, or intramural hematoma were excluded. Standard SF-36 and general health questionnaires were sent to all 124 survivors who could be traced. Follow-up was 98.4% complete. The mean age of the survivors was 61.7 ± 11 years, and 63.4% were men. Operative procedures consisted of supracoronary replacement of the ascending aorta in 35.9%, the Wheat procedure in 44%, the David procedure in 11.2%, the Bentall–DeBono procedure in 9%, and the Cabrol procedure in 2.2%. Patients were monitored until May 2005.Thirty-day and midterm mortality rates were 3.7% and 3.9%, respectively. Morbidity due to stroke was 6%, to bleeding 6%, and to myocardial infarction 4.4%. Postoperative quality-of-life evaluation revealed many subscales of SF-36 that were below the norm when compared with a standard population in physically dominated categories.Replacement of the dilated ascending aorta carries acceptable risk in regard to operative death and postoperative quality of life, although this last showed some decline in comparison with quality of life in a normal, healthy population.Key words: Aortic aneurysm, thoracic/surgery; blood vessel prosthesis; cardiac surgical procedures/adverse effects; health status indicators; health surveys; follow-up studies; quality of life; reference values; treatment outcomeAneurysms of the ascending aorta are considered to be a serious disease, particularly in elderly patients, because the operative risk is generally higher due to concomitant diseases. When left untreated, aneurysms carry a high mortality rate; often, they remain undiscovered until dissection or rupture. To avoid these sequelae, early diagnosis is essential. Data from many studies regarding the progression of aneurysms show that the risk of operation is justifiable in light of the probability of lethal sequelae to chronic, asymptomatic disease. Once an aneurysm reaches a maximum diameter of 6 cm, the annual probability of rupture, dissection, or death is 14.1%.¹Aside from morbidity and mortality rates, which are widely published, there is little information about quality of life among patients who have undergone major aortic surgery before dissection or rupture. However, quality of life is also an important consideration when evaluating the success of the operation, especially in patients whose aneurysms were not symptomatic before surgery.This study analyzes the operative outcome and quality of life among patients who have had the ascending aorta replaced, in comparison with quality of life among the general German population.     

Use of an intraluminal double-ring vascular prosthesis in thoracic aorta reconstruction

The authors present their initial experience with the use of the intraluminal double-ring prosthesis in the surgical treatment of thoracic aorta aneurysms. To date, they have performed this procedure in a total of 7 patients. Five had dissecting aneurysms of the ascending and descending aorta, one had a false aneurysm of the aortic arch, and one was operated on for a traumatic aneurysm of the descending aorta. Five patients recovered without any severe complications. Two patients died. Of these, one underwent surgery on an emergency basis for ruptured dissecting aneurysm of the ascending aorta while another died from intestinal gangrene due to occlusion of the upper mesenteric artery, caused by dissection. The benefits of the new technique of vascular reconstruction are discussed, and the potential for expanded indicational criteria is mentioned.     

Liver resection in a patient with concomitant thoraco-abdominal and cerebral aneurysms

Background. Surgical resection remains the only curative procedure for liver metastases but even in expert hands it has appreciable morbidity and mortality rates. The presence of a concomitant aortic aneurysm greatly increases these risks. Case outline. A 66-year-old woman who was known to have large aneurysms of the thoraco-abdominal aorta and middle cerebral artery presented with colorectal liver metastases. After detailed preoperative assessment, she underwent resection of segments V and VI of the liver. The surgical procedure was uneventful. She made a good initial recovery, but on day 7 she suddenly became hypotensive and died from a cardiorespiratory arrest. Post-mortem examination revealed a ruptured thoracic portion of the thoraco-abdominal aortic aneurysm. Conclusion. Despite careful control of perioperative blood pressure and the lack of abdominal complication, intrathoracic aneurysmal rupture on day 7 highlights the risk of major unrelated operations in patients with aneurysmal disease.