Thoracoabdominal aneurysm resection after previous infrarenal abdominal aortic aneurysmectomy

Visceral segment aortic thrombus is associated with proximal aortic degeneration after infrarenal abdominal aortic aneurysm repair

OBJECTIVE

To identify predictors of aortic aneurysm formation at or above an infrarenal abdominal aortic aneurysm repair.

METHODS

A total of 881 infrarenal abdominal aortic aneurysm repairs were identified at a single institution from 2004 to 2008; 187 of the repairs were identified that had pre-operative and post-operative computed tomography imaging at least one year or greater to evaluate for aortic degeneration following repair. Aortic diameters at the celiac, superior mesenteric, and renal arteries were measured on all available computed tomographic scans. Aortic thrombus and calcification volumes in the visceral and infrarenal abdominal aortic segments were calculated. Multivariable modeling was used with log transformed variables to determine potential predictors of future aortic aneurysm development after infrarenal abdominal aortic aneurysm repair.

RESULTS

Of the 187 patients in the cohort, 100 had an open abdominal aortic aneurysm repair while 87 were treated with endovascular repair. Proximal aortic aneurysms developed in 26% (n = 49) of the cohort during an average of 72 ± 34.2 months of follow-up. After multivariable modeling, visceral segment aortic thrombus on pre-operative computed tomography imaging increased the risk of aortic aneurysm development above the infrarenal abdominal aortic aneurysm repair within both the open abdominal aortic aneurysm (hazard ratio 2.04, p = 0.033) and endovascular repair (hazard ratio 3.31, p = 0.004) cohorts. Endovascular repair was independently associated with a higher risk of future aortic aneurysm development after infrarenal abdominal aortic aneurysm repair when compared to open abdominal aortic aneurysm (hazard ratio 2.19, p = 0.025).

CONCLUSIONS

Visceral aortic thrombus present prior to abdominal aortic aneurysm repair and endovascular repair are both associated with an increased risk of future proximal aortic degeneration after infrarenal abdominal aortic aneurysm repair. These factors may predict patients at higher risk of developing proximal aortic aneurysms that may require complex aortic repairs.

Effect of PJ34 on spinal cord tissue viability and gene expression in a murine model of thoracic aortic reperfusion injury

INTRODUCTION

These studies were designed to determine whether PJ34, a novel Poly-ADP Ribose Polymerase Inhibitor, modulates expression of markers of stress and inflammation in the spinal cord following ischemia/ reperfusion(TAR).

METHODS

129S1/SvImj mice were subjected to thoracic aortic occlusion and 48 hours of reperfusion (n = 38). EXPERIMENTAL GROUPS INCLUDED: Untreated Control (UC, n = 21); PJ34 (PJ34, n = 11) and sham (S, n = 6). At 48 hours, mice were euthanized for mRNA analysis and assessment of spinal cord viability.

RESULTS

PJ34 improved spinal cord tissue viability following TAR (UC:53.1 +/- 6.3, PJ34:73.5 +/- 4.1% sham, p < 0.01). mRNA analysis revealed significant expression of stress response genes in UC and PJ34 treated mice.

CONCLUSIONS

PJ34 enhanced mitochondrial activity and preserved neurologic function following TAR despite the expression of stress and pro-inflammatory markers within the spinal cord. The ongoing cord stress response in neurologically intact PJ34 treated mice may indicate the potential to develop delayed neurologic dysfunction.

Risk of spinal cord injury after operations of recurrent aneurysms of the descending aorta

BACKGROUND

Degenerative disease of the aorta usually involves the occlusion of several intercostal and lumbar branches by mural thrombus or atherosclerotic plaques, suggesting that the blood supply to the spinal cord is mainly provided through collateral networks. Patients with previous abdominal aortic aneurysm repair and subsequent thoracoabdominal aortic reconstruction must undergo ligation of a number of these segmental arteries, presenting a greater risk of experiencing spinal cord ischemic injury.

METHODS

The records of 18 patients who had experienced abdominal aortic aneurysm graft replacement and who had undergone 19 operations for thoracoabdominal aortic repair were retrospectively evaluated. All patients were male. The mean age was 66 +/- 10 years (range, 36 to 75 years); the mean interval between the two operations was 79 +/- 69 months (range, 1 to 231 months). There were 18 (95%) cases of thoracoabdominal aortic aneurysms, and one (5%) case of acute dissection of the thoracoabdominal aorta. The origin of the Adamkiewicz artery was determined preoperatively by computed tomography. Measures to avoid spinal cord injury included monitoring of evoked spinal cord potentials and selective reconstruction of the intercostal arteries under hypothermic cardiopulmonary bypass.

RESULTS

There were three (16%) cases of permanent neurologic injury that included one cerebrovascular accident, one neurogenic bladder, and one paraparesis of the right lower limb. There were no cases of paraplegia or postoperative deaths.

CONCLUSIONS

Surgical reconstruction of the thoracoabdominal aorta in patients who previously underwent abdominal aortic graft replacement is not related to an increased probability of developing spinal cord ischemic injury.

Thoracovisceral segment aneurysm repair after previous infrarenal abdominal aortic aneurysm surgery

OBJECTIVE

Repair of thoracovisceral aortic aneurysms (TVAA) after previous open repair of an infrarenal abdominal aortic aneurysm (AAA) poses significant challenges. We sought to better characterize such recurrent aneurysms and to evaluate their operative outcome.

METHODS

We reviewed the records and radiographs of 49 patients who underwent repair of TVAAs between 1988 and 2002 after previous repair of an AAA. Visceral artery reconstructions were completed with combinations of beveled anastomoses, inclusion patches, and side arm grafts. In 14 patients visceral endarterectomy was required to treat associated occlusive disease. Sixteen patients had cerebrospinal fluid drainage, and 10 patients had distal perfusion during cross-clamping.

RESULTS

Patient mean age was 72 years, and 80% were men. Fifty-one percent of patients had symptomatic disease, and average TVAA diameter was 6.2 cm. Mean time between AAA and TVAA repair was 77 months. Twenty-six percent of aneurysms were restricted to the lower visceral aortic segment, 35% extended to the diaphragm, another 35% extended to the distal or middle thoracic aorta, and 4% involved the entire remaining visceral and thoracic aorta. The 30-day operative mortality rate was 4.1% in patients with nonruptured aneurysms and 50% in patients with ruptured aneurysms, for an overall mortality rate of 8.2%. Fifteen patients (30.6%) had major morbidity, including paresis in two patients and dialysis-dependent renal failure in five patients. At late follow-up, three patients required further aortic operations to treat additional aneurysms, and four patients had fatal aortic ruptures. Two-year and 5-year cumulative survival rates were 61% (+/-7.5%) and 37% (+/-7.8%), respectively. At univariate analysis, operative blood loss was the sole significant predictor of major morbidity (P <.023), and rupture (P <.030, P <.0001) and aneurysm extent (P <.0007, P <.0001) correlated with both operative death and long-term survival. Only aneurysm extent (P <.010, relative risk 37.3) remained a significant predictor of long-term survival at multivariate analysis.

CONCLUSION

Elective repair of TVAAs after previous AAA repair can be performed with an acceptable level of operative mortality, though with considerable operative morbidity. Limited long-term survival mandates careful patient selection, and the high mortality associated with ruptured TVAA underscores the need for post-AAA surveillance.

Surgical treatment of thoracoabdominal aortic aneurysm after repairs of descending thoracic or infrarenal abdominal aortic aneurysm

OBJECTIVE

The outcome of thoracoabdominal aortic aneurysm repair after operations for descending thoracic or infrarenal abdominal aortic aneurysm was investigated.

METHODS

Between May 1982 and July 2000, 102 patients underwent thoracoabdominal aortic aneurysm repair. Of these patients, 36 had previously undergone operations for descending thoracic or abdominal aortic aneurysm. To evaluate the influence of previous descending thoracic or infrarenal abdominal aortic aneurysm repair on the results of TAAA replacement, patients were divided into two groups: one group of patients who had previously undergone descending thoracic or infrarenal abdominal aortic aneurysm repair (group I, n=36) and one group of patients who had not previously undergone descending thoracic or infrarenal abdominal aortic aneurysm repair (group II, n=66).

RESULTS

Patients with previous descending thoracic or infrarenal abdominal aortic aneurysm repair had more chronic dissection and extensive thoracoabdominal aortic aneurysm. The distal aortic perfusion time and total aortic clamp time were both longer in group I. The total selective visceral and renal perfusion time and operation time did not differ significantly between the two groups. In 30-day mortality rates were 5.5% in group I and 13% in group II. Major postoperative complications included paraplegia in 14% of patients in group I and 3.1% in group II, renal failure requiring hemodialysis in 22% of patients in group I and 19% of patients in group II, respiratory failure in 36% of patients in group I and 30% of patients in group II, postoperative hemorrhage in 11% of patients in group I and 16% of patients in group II.

CONCLUSION

The presence of a previous descending thoracic or infrarenal abdominal aortic aneurysm did not adversely affect the outcome of thoracoabdominal aortic aneurysm repair.

Acute renal failure after redo thoracoabdominal aortic aneurysm repair in a patient with a solitary kidney: successful percutaneous treatment

PURPOSE

To report the successful percutaneous treatment of renal artery stenosis that precipitated renal failure following surgical repair of a thoracoabdominal aortic aneurysm (TAAA).

METHODS AND RESULTS

A 70-year-old woman with a solitary kidney became anuric 2 hours after urgent repair of a symptomatic true aneurysm of the Carrel patch from an 8-year-old TAAA repair. After medical treatment failed, aortography was performed, identifying complete occlusion of the solitary renal artery. Balloon dilation and implantation of a Palmaz stent restored renal perfusion and improved function. At 6-month follow-up, she was normotensive and her creatinine within normal limits.

CONCLUSIONS

Renal artery stenosis or occlusion is a treatable cause of acute renal failure after TAAA repair. Percutaneous treatment options are likely to be better tolerated than surgical revascularization in this patient population.

Surgical repair of aneurysms involving the suprarenal, visceral, and lower thoracic aortic segments: early results and late outcome

OBJECTIVE

The purpose of this study is to review our experience with surgical repair of lower thoracoabdominal and suprarenal aortic aneurysms to determine early and late survival rates and identify factors influencing morbidity and survival among these patients.

MATERIALS

From 1989 through 1998, 165 consecutive patients underwent repair of 108 thoracoabdominal (55 group III and 53 group IV) and 57 suprarenal aneurysms. The study group consisted of 109 men and 56 women with a mean age of 70 years (median, 70 years; range, 29-89 years). Mean aneurysm diameter was 6.9 cm (median, 6.5 cm; range, 4-12 cm). There were 125 aneurysms (76%) repaired electively; 40 repairs (24%) were nonelective. The cause of 12 aneurysms (7%) was chronic aortic dissection; the remaining 153 (93%) were degenerative aneurysms.

RESULTS

The early postoperative (30-day) mortality rates were 7% (9/125) for elective and 23% (9/40) for nonelective operations (P =.016). For both elective and urgent procedures, early mortality was 1.8% (1/57) for suprarenal aneurysm repair, 11% (6/53) for group IV thoracoabdominal aneurysms, and 20% (11/55) for group III thoracoabdominal aneurysms (P =.013, suprarenal vs group III). Spinal cord ischemia occurred after 6% (10/165) of aneurysm repairs (4% paraplegia, 2% paraparesis). None of the 57 suprarenal aneurysm repairs were complicated by spinal cord ischemia, whereas it occurred in 2% (1/53) of group IV thoracoabdominal aneurysms and 16% (9/55) of group III thoracoabdominal aneurysms (P =.001, suprarenal vs group III; P =. 016, group IV vs group III). Three (25%) of the 12 patients with dissection developed spinal cord ischemia; this compared with seven (5%) of 153 patients with degenerative aneurysms (P =.027). The cumulative 3-year survival rate for the entire series was 71% (95% CI, 64%-79%), and 5-year survival was 50% (95% CI, 40%-60%).

CONCLUSIONS

Aneurysms involving the suprarenal, visceral, and lower thoracic aorta may be repaired with acceptable perioperative mortality and late survival rates. The risk of spinal cord ischemia is increased for patients with aortic dissection and may be stratified according to the proximal extent of the aneurysm.

Successful surgical treatment of impending rupture of thoracoabdominal aortic aneurysm in an elderly patient with severe pulmonary emphysema

In a case of successful surgery for impending thoracoabdominal aortic aneurysmic rupture, an 83-year-old man with severe pulmonary emphysema was transferred to our hospital diagnosed with impending aneurysmic rupture. The aneurysm had been pointed out 2.5 years ago but surgical repair was not undertaken due to the patient's severe pulmonary emphysema. After admission, computed tomography showed an enlarging saccular thoracoabdominal aortic aneurysm. Emergency surgery was conducted because of severe pain below the left costal margin. We resected the wall of the saccular aortic aneurysm and reconstructed the aorta with an on-lay patch under femoro-femoral bypass and selective visceral organ perfusion. Tracheostomy provided respiratory care on the day following surgery. The patient was weaned from respiratory support 6 days after surgery. Postoperative aortography showed that the reconstructed thoracoabdominal aorta functioned satisfactorily. The patient remains in good health 18 months after surgery.

Renal failure after thoracoabdominal aortic surgery

PURPOSE

Renal failure remains a common and morbid complication after complex aortic surgery. This study was performed to identify perioperative factors that contribute to postoperative renal failure.

METHODS

The perioperative outcomes of 183 patients who underwent thoracoabdominal aortic surgery with supraceliac clamping were reviewed. During the interval from Jan. 1987 to Nov. 1996, thoracoabdominal aneurysm repair was performed in 154 patients (type I, 49 patients [27%]; type II, 21 patients [11.5%]; type III, 55 patients [30%]; type IV, 29 patients [16%]), suprarenal abdominal aortic aneurysm repair in 17 patients (9%), and visceral/renal revascularization procedures in 12 patients (6.5%). Intraoperative management included thoracoabdominal aortic exposure and clamp-and-sew technique with renal artery cold perfusion whenever the renal arteries were accessible (79% of cases).

RESULTS

Relevant clinical features included preoperative hypertension (85%), diabetes mellitus (8%), single functioning kidney (10%), recent intravenous contrast injection (34%), renal insufficiency (creatinine level greater than 1.5 mg/dl; 24%), and emergent operation (19%). Acute renal failure, defined as both a doubling of serum creatinine level and an absolute value greater than 3.0 mg/dl, occurred in 21 patients (11.5%), of whom five required hemodialysis (2.7%). Variables associated with this complication included a preoperative creatinine level greater than 1.5 mg/dl (p = 0.004) and a total cross-clamp time greater than 100 minutes (p = 0.035). The operative mortality risk (within 30 days; 8%) was significantly increased with renal failure (odds ratio, 9.2; 95% confidence interval, 2.6 to 33; p < 0.005).

CONCLUSIONS

Renal failure, although uncommon in contemporary practice, greatly increases the risk of early death after thoracoabdominal aortic surgery. The overall incidence of renal failure and dialysis requirement in the present series compare favorably with those reported using other operative techniques, specifically partial left heart bypass and distal aortic perfusion. These data suggest that patients who have preoperative renal insufficiency are prone to postoperative renal failure. Furthermore, regional hypothermic perfusion and minimal clamp times are important elements in the prevention of renal failure after thoracoabdominal aortic surgery.

Impact of previous thoracic aneurysm repair on thoracoabdominal aortic aneurysm management

BACKGROUND

The purpose of this study was to determine the impact of previous thoracic aortic aneurysm repair (PTAR) on subsequent thoracoabdominal aortic aneurysm operations.

METHODS

A retrospective review of 723 thoracoabdominal aortic aneurysm repairs over a 10-year period facilitated comparison of 179 patients (24.8%) with PTAR and 544 patients (75.2%) without PTAR.

RESULTS

Patients with PTAR had more chronic dissections and extensive thoracoabdominal aortic aneurysms, and consequently required longer clamp and ischemic times and more intraoperative transfusions. Patients without PTAR were older, had more preoperative comorbid disease, and had more symptomatic or ruptured aneurysms. Although differences did not reach statistical significance, patients without PTAR tended toward increased in-hospital mortality (8.5% versus 4.5%; p = 0.078) and postoperative paraplegia/paraparesis rates (6.5% versus 2.8%; p = 0.069). More patients without PTAR had cardiac complications (11.3% versus 5.6%; p = 0.028) and required chronic hemodialysis (5.9% versus 1.1%; p = 0.009).

CONCLUSIONS

The presence of a PTAR did not adversely affect the outcome of thoracoabdominal aortic aneurysm repair. After thoracic aortic aneurysm repair, life-long radiologic surveillance and early surgical treatment are justified.

Improvement in results of repair of type IV thoracoabdominal aortic aneurysms

PURPOSE

Although management of extensive type I and II thoracoabdominal aortic aneurysms (TAA) remains a formidable challenge, results of repair of TAA originating in the distal thoracic aorta (type IV) appear to have improved significantly. To quantitate this perceived improvement, the following retrospective study was undertaken to examine the results of type IV TAA repair at the Brigham & Women's Hospital over the past 18-year period.

METHODS

From July 1977 to September 1994, nonruptured atherosclerotic type IV TAAs were repaired in 58 patients. The mean age was 70 years, and associated risk factors included smoking (91%), hypertension (86%), coronary artery disease (52%), and previous aortic surgery (38%). Mean follow-up was 2.4 years (median 2 years).

RESULTS

Overall 30-day mortality was 5.3% (two deaths). Morbidity included stroke (3.5%), paraplegia (1.8%), permanent paraparesis (1.8%), myocardial infarction (7%), pneumonia (8.8%), gastrointestinal bleeding (11%), intestinal ischemia (5.3%), wound infection (7.0%), peripheral ischemia (5.3%), in-hospital dialysis (8.8%), and permanent dialysis (1.9%). Overall 5-year survival was 50%. With univariate analysis, survival was positively correlated with more recent year of operation (p = 0.002), smaller volume of intraoperative blood transfusion (p = 0.02), decreased supraceliac ischemia time (p = 0.04), and the use of the retroperitoneal approach (p = 0.09). Multiple regression analysis revealed that the year of operation was the only independent predictor of survival (p = 0.003). Subgroup analysis of patients who underwent operation between 1977 and 1987 (n = 13) and 1988 and 1994 (n = 45) revealed statistically significant improvements in length of hospital stay (46 +/- 12 vs 21 +/- 4 days, p = 0.02), postoperative dysrhythmia (50% vs 16%, p = 0.03), postoperative maximum serum glutamic oxaloacetic-transaminase (516 +/- 234 vs 319 +/- 139 mg%, p = 0.04), incidence of hemorrhage requiring reexploration (33% vs 0%, p = 0.002), 30-day mortality (23% vs 0%, p = 0.009), and in-hospital mortality (39% vs 2.2%, p = 0.002).

CONCLUSIONS

The modern mortality, morbidity, and survival of surgical repair of type IV TAA in our institution approaches that of infrarenal abdominal aortic aneurysm.

Subsequent proximal aortic operations in 123 patients with previous infrarenal abdominal aortic aneurysm surgery

PURPOSE

Previous studies have reported that 3% to 8% of patients who have had resection of an infrarenal abdominal aortic aneurysm will subsequently have development of a new aortic aneurysm proximal to the repair. The actual incidence, pathogenesis, and natural history of these aneurysms are unclear. The purpose of this study is to better characterize subsequent proximal aortic aneurysms and to evaluate the outcome of their operative repair.

METHOD

We retrospectively reviewed our recent experience with surgery for new proximal aortic aneurysms in 123 patients who had had a prior abdominal aortic aneurysmectomy. Seventy-two patients (58.5%) were admitted with chest or abdominal pain, six (4.9%) were admitted with ruptured aneurysms, and 41 (33.3%) were symptom free. Most subsequent aneurysms involved the thoracoabdominal aorta (n = 94; 76.4%); others involved the juxtarenal abdominal aorta, descending thoracic aorta, or transverse aortic arch. The new aneurysm was in continuity with the existing prosthetic graft in 101 cases (82.1%). Resection and graft replacement of the aneurysmal segment was performed on an emergency basis in patients with evidence of impending rupture and electively when aneurysmal diameter exceeded 5.5 cm. The average time interval between the two operations was 8.2 +/- 5.4 years. Mean aortic clamp and visceral ischemic times were 39.7 +/- 14.7 and 33.5 +/- 12.8 minutes, respectively.

RESULTS

The in-hospital mortality rate was 12.2%. Complications included oliguric kidney failure in 11.4% and paraplegia in 4.1%. These results compare favorably with previous studies.

CONCLUSION

On the basis of the significant prevalence of subsequent proximal aortic aneurysms and the high mortality rate associated with their rupture, we recommend resection of the entire infrarenal aorta during abdominal aortic aneurysm replacement, followed by long-term surveillance with biannual computed tomography or magnetic resonance imaging scanning of the chest and abdomen. Early diagnosis is facilitated by a high index of suspicion and allows surgical intervention to occur before life-threatening rupture. Both emergency and elective proximal aortic surgery in these patients can be performed with acceptable levels of morbidity and mortality.