Distal Aortic Dissection Research Articles

Dissecção espontânea da aorta abdominal infrarrenal

A rotura da camada íntima que marca o início da dissecção aórtica se origina na maioria dos casos na aorta torácica, sendo rara a dissecção espontânea da aorta abdominal infra-renal. As três principais causas são: iatrogênica, traumática ou espontânea. A dor abdominal e a isquemia de membros são os sintomas mais comuns e um número significativo de pacientes e´ assintomatico. O diagnóstico tem sido feito através de métodos de imagem como ultrassonografia, tomografia computadorizada, ressonância nuclear magnética e angiografia aliados ao alto índice de suspeição. Relatamos os casos de duas pacientes que apresentaram dissecção de aorta abdominal infrarrenal com quadro de dor abdominal súbita, sem sinais de irritação peritoneal com pulsos presentes e simétricos ao exame físico que deram entrada no pronto socorro do Hospital e Maternidade Celso Pierro da PUC Campinas e que foram tratadas pela equipe de Cirurgia Vascular. As duas pacientes no momento do exame apresentavam-se hipertensas e ao ultrassom apresentavam alteração da conformidade da aorta abdominal que foram tratada s cirurgicamente. Uma paciente foi tratada cirurgicamente submetida a endarterectomia da placa dissecada da aorta abdominal infrarrenal de 2,2 cm de diâmetro e 2,0 cm de extensão. A outra paciente foi submetida a revascularização da aorta abdominal bi-iliaca com prótese de Dacron 16 × 8 mm por apresentar disseccao da aorta abdominal distal. As duas pacientes apresentaram boa evolução pos-operatoria tendo alta hospitalar em bom estado geral.

Open repair of chronic distal aortic dissection in the endovascular era: Implications for disease management

Controversy surrounds the treatment of chronic aortic dissection. Open surgical and endovascular experiences include mixed populations treated with evolving strategies and limited follow-up. We establish a standard against which endovascular repair can be compared by assessing outcomes after open repair of chronic distal aortic dissections anatomically suitable to stent-grafting. From 2000 to 2008, 169 patients underwent open repair of the descending thoracic artery only (n=88) or thoracoabdominal (n=81) chronic aortic dissection (elective in 98, urgent/emergency in 71). Chart review and 3-dimensional assessment of computed tomography were performed. Poor outcome included all-cause mortality or vascular reintervention. Thirty-day mortality was 8% (n=14). Serious complications included neurologic (n=12 [spinal cord n=4, 2.4%]), respiratory (n=32), and renal failure (n=1 descending thoracic artery only vs 17 thoracoabdominal, P<.001). Chronic obstructive pulmonary disease predicted early mortality (hazard ratio 8.0, P=.005). Survival at 1, 2, and 5 years was 76%, 69%, and 55%, respectively; 23 patients (14%) required reintervention. Event-free survival at 5 years was 51% and 47% after descending thoracic artery only or thoracoabdominal repair, respectively. Greater maximum aortic diameter (hazard ratio 1.9, P=.03) and greater diameter at the diaphragm (hazard ratio 3.7, P=.01) or renal segment (hazard ratio 4.3, P=.03) predicted poor outcome. Early outcomes are good and late outcomes are less than desirable after open repair of chronic distal aortic dissection, regardless of the extent of repair. High-risk and late-stage patients with larger and more extensive aneurysmal degeneration warrant further investigation, including the use of newer, less-invasive techniques. Select patients at risk for aneurysmal degeneration should undergo a more aggressive initial approach with aortic dissection repair.

Endovascular repair of complicated chronic distal aortic dissections: Intermediate outcomes and complications

Patients with chronic distal aortic dissection (CDAD) remain at high risk for late aorta-related events and reinterventions, and the ideal management strategy remains undefined. Open surgical procedures carry morbidity, but scant data for thoracic endovascular aortic repair (TEVAR) of CDAD exist. This study reports our intermediate-term results with TEVAR for complicated CDAD. All cases of TEVAR for complicated (aortic growth, malperfusion, intractable pain) CDAD at our institution between 2000 and 2007 were retrospectively reviewed. Demographic information, indications for repair, complications, and aortic morphologic changes were collected from medical records and imaging studies. Aortic morphology (aneurysm size, false lumen thrombosis) was assessed at multiple levels with 3-dimensional image analysis techniques. Kaplan-Meier analysis was used to estimate survival, freedom from reintervention, and likelihood of false lumen thrombosis, with log-rank tests used to discriminate between Kaplan-Meier curves. In total, 144 stent-grafts were implanted in 76 consecutive patients (49 male) with complicated CDAD. Early (<30 postoperative days) mortality was 5%. There was no paraplegia, and 1 patient died of stroke. At mean follow-up of 34 months, 12 patients had died (1 aorta-related death). Seventeen patients (22%) underwent 19 secondary aortic reinterventions, mainly for enlargement of the untreated aorta remote to stent-graft repair. Three secondary procedures treated retrograde proximal dissections. Estimated survivals were 86%, 82%, and 80% at 12, 24, and 36 months, respectively, and freedoms from both death and reintervention were 72%, 64%, and 59% at similar time points. Of 67 patients (88%) with complete imaging follow-up, TEVAR resulted in significantly decreased aortic diameter through the stent-grafted segment but not untreated segments. Complete thrombosis of the entire false lumen was uncommon in patients with extensive dissections (13% vs 78% P < .001). Management of complicated CDAD remains challenging for clinicians. TEVAR is a reasonable treatment modality for dissections limited to the thoracic aorta and for prevention of focal aortic growth in extensive dissections. Late complications and the need for secondary interventions emphasize the complexity of this patient population and the need for long-term follow-up.

Long-Term Survival After Open Repair of Chronic Distal Aortic Dissection

The optimal treatment of chronic distal aortic dissection remains controversial, with endovascular stent-graft techniques challenging traditional surgery. From January 1994 to April 2007, 104 patients (82 male, median age 60.5 years) with chronic distal aortic dissection underwent surgical repair, 0 to 21 years after initial diagnosis of acute type A or B dissection (median 2.1 years). Twenty-three (22%) patients underwent urgent-emergent surgery. Mean aortic diameter was 6.9 +/- 1.4 cm. Indications for surgery, other than aortic expansion, were pain in 6 (6%) patients, malperfusion in 6 (6%), and rupture in 11 (11%). Forty-nine (47%) had previous cardioaortic surgery (29% dissection-related), 21 (20%) had coronary artery disease, 12 (12%) had Marfan syndrome, and 4 (4%) were on chronic dialysis. Twenty-six (25%) had a thrombosed false lumen. Thirty (29%) patients required reimplantation of visceral arteries; 8.3 +/- 2.7 segmental artery pairs were sacrificed. Hospital mortality was 9.6% (10 patients). Paraplegia occurred in 5 (4.8%). Twenty-seven patients (26%) experienced adverse outcome (death within one year, paraplegia, stroke, or dialysis). Adverse outcome was associated with atheroma (p = 0.04, odds ratio = 4.3). Survival was 78% at 1, 68% at 5, and 59% at 10 years (average follow-up, 7.7 +/- 4.1 years). Freedom from distal aortic reoperation was 99% at 1, 93% at 5, and 83% at 10 years. After one year, patients enjoyed longevity equivalent to a normal age-sex matched population (standardized mortality ratio = 1.38, p = 0.23). By multivariate analysis, atheroma (p = 0.0005, relative risk = 9.32) and age (p = 0.0003, relative risk = 1.15/year) were risk factors for long-term survival. The efficacy of open repair for distal chronic dissection is highlighted by normal survival after the first year, and a low reoperation-reintervention rate.

Invited Commentary

Invited Commentary

Endovascular management of chronic aortic dissection in patients with Marfan syndrome

Marfan syndrome patients are prone to aortic dilatation, dissection, and rupture. Success of aortic root replacement has generated a cohort of patients surviving longer and presenting with distal aortic dissection and enlargement. Thoracic endovascular stent-graft repair (TEVR) is being increasingly utilized to exclude aneurysms resulting from chronic aortic dissection. This report explores the role of TEVR in Marfan patients with this pathology. Review of a prospectively maintained database identified seven patients with Marfan syndrome offered endovascular repair of aneurysmal chronic aortic dissection. All patients had previous aortic root repair. Talent or Valiant (Medtronic Vascular, Santa Rosa, Calif) aortic stent-grafts were used to occlude the dissection entry tear and cover the thoracic aorta. Electronic data, case notes, and radiological surveillance were analyzed. Seven consecutive patients (six male; mean age, 45.9 +/- 10 years, range, 29 to 63) underwent successful thoracic stent-graft deployment. Mean aortic aneurysmal diameter was 63.4mm (+/-11.2) with six of seven dissections extending to the aortic bifurcation. No perioperative neurological events occurred. Thirty-day mortality was 1/7 (14%) due to congestive cardiac failure. At median 16 month follow-up, two of six cases (33%) required intervention for endoleak. Aortic false lumen thrombosis (FLT) occurred in 5/6 (83%) cases and partial FLT occurred in 1/6 (17%). All thoracic aortas continued to dilate during follow-up. Crude median aortic growth rate was 7.2 mm/year (range, 3.5 to 19 mm). TEVR in Marfan syndrome patients with chronic aortic dissection is technically feasible. However, post intervention surveillance confirms that the aorta continues to dilate despite graft deployment and false lumen thrombosis. Endovascular repair may offer a viable option in patients who have contraindications to open surgery, but longer follow up of more patients is required to define the place of this therapy.

Early use of beta-blockers attenuates systemic inflammatory response and lung oxygenation impairment after distal type acute aortic dissection

We have reported that serum C-reactive protein (CRP) elevation is an independent predictor of lung oxygenation impairment (LOI) after distal type acute aortic dissection (AAD). Systemic activation of the inflammatory system after aortic injury may play a role in the development of LOI. The aim of this study is to clarify the effect of beta-blockers on systemic inflammation and the development of LOI after distal type AAD. A total of 49 patients, who were admitted with distal type AAD and treated conservatively, were examined. White blood cell (WBC) count, serum CRP level, and arterial blood gases were measured serially. Forty patients received beta-blocker treatment within 24 h of the onset, while 9 patients received no beta-blocker treatment. Maximum WBC count, maximum CRP level, lowest PaO2/FiO2 (P/F) ratio, and patient background were compared between the two groups. There was no difference between the groups according to age, sex, coronary risk factors, blood pressure, serum level of CRP, WBC count, and oxygenation index on admission. Beta-blocker treatment was associated with lower maximum WBC count (P = 0.0028) and lower maximum serum CRP level (P = 0.0004). The minimum P/F ratio was higher in patients with beta-blocker treatment than in those without (P = 0.0076). Multivariate analysis revealed that administration of a beta-blocker was an independent negative determinant of LOI (P/F ratio ≤200 mmHg). In conclusion, early use of beta-blockers prevented excessive inflammation and LOI after distal type AAD, suggesting a pleiotropic effect of beta-blockers on the inflammatory response after AAD.

Invited Commentary

Advances in the surgical management of acute aortic dissection involving the ascending aorta have resulted in significant improvement in morbidity and mortality. However, conventional surgical technique designed to address the ascending aortic pathology often results in leaving residual dissection in the descending thoracoabdominal aorta. The management of late aneurysmal formation in the remaining distal aorta remains a clinical challenge. Even in a contemporary series, distal reoperation of thoracoabdominal aortic aneurysms in the setting of chronic dissections has been associated with perioperative mortality up to 30% [1Geirsson A. Bavaria J.E. Swarr D. et al.Fate of the residual distal and proximal aorta after acute type A dissection repair using a contemporary surgical reconstruction algorithm.Ann Thorac Surg. 2007; 84: 1955-1964Abstract Full Text Full Text PDF PubMed Scopus (197) Google Scholar]. Jakob and coauthors [2Jakob H. Tsagakis K. Tossios P. et al.Combining classic surgery with descending stent grafting for acute DeBakey type I dissection.Ann Thorac Surg. 2008; 86: 95-102Abstract Full Text Full Text PDF PubMed Scopus (95) Google Scholar] propose a novel modification of the conventional open repair in an attempt to alter the fate of distal residual aortic dissection and possibly improve long-term outcome. The fundamental question is: “Does obliteration of the false lumen in the distal aorta (with the use of stent graft therapy) positively affect aortic remodeling and prevent aneurysmal formation?” In this series, 45 patients with acute DeBakey type I aortic dissection underwent either conventional surgery (n = 23) or hybrid repair (n = 22). The hybrid repair consists of conventional surgical repair of the ascending aortic dissection with concomitant stent graft therapy of the descending thoracic aorta. The hypothesis is that stent graft therapy of the descending thoracic aorta results in the obliteration and thrombosis of the false lumen, thus preventing aneurysmal formation of the distal thoracoabdominal aorta. The authors should be congratulated for their remarkable results on such a difficult group of patients. Their overall operative mortality was 16% (conventional surgery, 22%; hybrid, 9%; p = 0.22). Despite higher incidences of cerebral malperfusion and hemodynamic compromise in the hybrid group, there was no difference in mortality. In terms of the conduct of the operations, there was no difference in the duration of CPB, selective antegrade cerebral perfusion and deep hypothermia and circulatory arrest. Interestingly, the duration of the aortic cross clamp was shorter in the hybrid group. Postoperative results were also similar between the two groups. There was no difference in operative mortality, renal failure, stroke, and intubation time. By demonstrating no differences in the perioperative and short-term outcome between the two groups, the authors reassure us that the advances made in the proximal reconstruction and surgical outcome of ascending aortic dissection have not been compromised with this new technique. I believe this is an important point that the authors have appropriately emphasized. However, the main question of the study lies in the fate of the distal aorta (ie, aortic remodeling) after proximal reconstruction of the aortic dissection. Although early results from this study is encouraging, the study is simply too small and the follow-up too short (23 months in the hybrid group) to make definitive conclusions. Nevertheless, the fundamental concept of distal aortic remodeling in aortic dissection is an important question that should be pursued. Larger studies with long-term follow-up are needed before definitive conclusions can be made. Other issues need to be addressed and answered. Will this technique have any impact on neurologic events, such as stroke or spinal cord ischemia? What is the optimal length of coverage of the descending thoracic aorta with the endograft, as this decision must be made in considering between the effectiveness of the therapy versus the risk of spinal cord ischemia and perhaps distal malperfusion? If false lumen patency persists in the thoracic aorta despite stent graft therapy (seen in 10% patients in this study), how does that affect aortic remodeling? Also, how does the presence of a stent graft in the descending thoracic aorta affect distal reoperations? The authors demonstrated that the hybrid operation can be performed safely with no difference in mortality from the conventional surgical approach. I believe this study serves an important role in defining the concept and setting the stage for future studies. Combining Classic Surgery With Descending Stent Grafting for Acute DeBakey Type I DissectionThe Annals of Thoracic SurgeryVol. 86Issue 1PreviewTo possibly prevent late complications after classic type A aortic dissection repair, the radical concept of ascending/arch replacement with simultaneous antegrade descending stent grafting using a hybrid prosthesis was applied and compared with conventional repair leaving the distal false lumen untreated. Full-Text PDF

Long-term results of the open stent-grafting technique for extended aortic arch disease

This report elucidates the long-term safety and effectiveness of extended aortic arch replacement with an open stent-grafting technique from our 12 years of experience. From 1994 to 2004, 126 patients (mean age 67.8 years) with different pathologic conditions of the aortic arch with extension to the descending aorta (57 dissections [acute/chronic = 31/26] and 69 aneurysms) were operated on with an open stent-grafting technique. During deep hypothermic circulatory arrest with selective cerebral perfusion, the stent graft was delivered through the transected proximal aortic arch, and arch replacement with a 4-branched prosthesis was performed. Operative mortality within 30 days was 3.2%. Perioperative morbidity included 7 (5.6%) strokes and 8 (6.3%) spinal injuries (paraplegia in 3, transient paraparesis in 5). Sixty-three percent of the patients were extubated within 24 hours. In long-term follow-up (mean 60.4 +/- 36.5 months, maximum 153 months), survival was 81.1%, 63.3%, and 53.7% at 1, 5, and 8 years. Five (3.9%) late endoleaks were observed but treated with successful additional endovascular repair. Freedom from endoleaks was 98.0%, 91.1%, and 91.1% for 1, 5, and 8 years, respectively. Long-term observation showed safety and good durability of the open stent-grafting technique for aortic arch disease. This technique could be an attractive treatment option for aortic arch aneurysm with distal extension and aortic dissection requiring aortic arch replacement.

Predictors for aneurismal formation

Predictors for aneurismal formation

Abstract 3307: Early Use of Beta-blockers Attenuates Systemic Inflammatory Response and Lung Oxygenation Impairment after Distal Type Acute Aortic Dissection

BACKGROUND: Systemic activation of the inflammatory system after aortic injury may play a role in the development of lung oxygenation impairment (LOI) in patients with acute aortic dissection (AAD). We have reported that serum C-reactive protein (CRP) elevation is an independent predictor of this complication. We evaluated the effect of beta-blocker on systemic inflammation and the development of LOI after distal type AAD. METHODS: A total of 49 patients, who were admitted with distal type AAD and treated conservatively, were examined. Patients were divided into 2 groups according to the presence or absence of beta-blocker treatment, started within 24 hours of the onset. White blood cell (WBC) count, serum CRP level and arterial blood gases were measured serially. Clinical outcome, maximum WBC count, maximum CRP level, and lowest PaO 2 /FiO 2 (P/F) ratio were compared between the two groups. RESULTS: There was no difference between the groups in patients’ backgrounds, blood pressure, serum level of CRP, WBC count and P/F ratio on admission. Beta-blocker treatment was associated with lower maximum WBC count (14,856 ± 3201 vs. 11,687 ± 2610 /mm 3 , p =0.0028) and lower maximum serum CRP level (28.2 ± 20.5 vs. 14.2 ± 5.6 mg/dl, p =0.0004). The minimum P/F ratio was higher in patients with beta-blocker than in those without (140 ± 41 vs. 226 ± 90 mmHg, p =0.0076). Multivariate analysis revealed that administration of a beta-blocker was an independent negative determinant of LOI (P/F ratio ≤ 200 mmHg). CONCLUSIONS: Early use of beta-blockers prevented excessive inflammation and LOI after distal type AAD, suggesting a pleiotropic effect of beta-blockers on the inflammatory response after AAD.

Presentation and outcome of Marfan's syndrome patients with dissection and thoraco-abdominal aortic aneurysm

In Marfan's syndrome, there is a paucity of data regarding intervention criteria for surgery of the dissected thoraco-abdominal aorta. A retrospective analysis of 22 Marfan's patients with distal aortic dissection managed between September 1999 and April 2006 was performed. Serial diameters and linear expansion rates were calculated from imaging studies and the outcome of intervention was analysed. There were 14/22 male patients (median age 38 years), and 18 had prior aortic surgery. Surgery was recommended in 20 patients and undertaken in 19 (1 died prior to operation). Of the operated patients, 2 presented with rupture, 2 with airway obstruction, 1 with intermittent paraplegia and 14 underwent planned surgery for increased expansion rate or pain. All patients had residual type A or chronic type B dissection. The median aortic dimension at surgery was 6.7 cm (interquartile range (IQR) 5.5-8.2). The preoperative mean expansion rate increased from 0.5 cm/year to 1.7 cm/year (p<0.001), prior to operation. Fifteen patients underwent Crawford Extent II, two underwent Extent I and two underwent Extent III repair. Profound hypothermia and CSF drainage was used in 16 and 18 patients, respectively. There was no early mortality, paraplegia or renal failure. At a median postoperative follow-up of 56 months (range 6-86), the survival of the operated cohort was 90%. Thoraco-abdominal aortic aneurysm repair in Marfan's syndrome can be performed with good outcomes. Intervention should be based on size or accelerated expansion. Any role of endovascular management needs careful consideration.

Treatment Methods for Spinal Cord Injury Caused by Acute Type B Aortic Dissection

Acute distal aortic dissection rarely causes spinal cord ischemia presenting with paraplegia or paraparesis. Spinal cord involvement has poor outcomes, and there is no established effective treatment for this disorder. In this report we describe the acute conservative treatment of two cases of paraplegia/paraparesis due to acute type B aortic dissection. Early reversal of lower-limb dysmobility was achieved.

Open stent-grafting: aborted procedure in a patient with mega aorta syndrome

Open stent-grafting is a recent technical modification of endoluminal stent-grafting, in which a stent-graft is inserted into the descending thoracic aorta through an opening in the aortic arch, to treat distal arch aneurysms or aortic dissection. Controversy remains as to whether patients with mega aorta syndrome, or those with very wide aneurysm necks, could be candidates for stent-graft treatment--open or endoluminal. We recently attempted open stent-grafting in a patient with mega aorta syndrome who had a distal aortic arch aneurysm. A previous attempt at surgical resection of the aneurysm through left thoracotomy ended in failure because of severe adhesion in the left lung. This time, we planned total arch replacement with open stent-graft exclusion of the aneurysm. However, open stent-grafting had to be abandoned intraoperatively due to technical difficulties as well as our lack of experience with such difficult cases. Conventional total arch replacement with elephant trunk was performed instead. Due to its deep location, the distal neck of the aneurysm could not be reached through median sternotomy and, therefore, the distal aortic anastomosis was performed within the aneurysm cavity. Thus, the distal portion of the aneurysm was not excluded from circulation. The future treatment plan in the present case is further complicated by the fact that a second-stage surgery through left thoracotomy will not be possible. Conventional total arch replacement proved rather inappropriate as a treatment strategy in the present case. Open stent-grafting might have been a more useful approach is spite of the challenges posed by the aneurysm. There needs to be a consensus as to whether patients with mega aorta syndrome or those with very wide aneurysm necks could be candidates for stent-graft treatment--open or endoluminal in difficult circumstances.

Celiac Artery Compression Syndrome Due to Acute Type B Aortic Dissection

Acute distal aortic dissection sometimes causes one or more visceral vessels to be stenosed by the thrombosed false lumen. Although stenosis of the only celiac artery (CA) usually does not cause ischemic symptoms because of the extensive collateral pathways of the mesenteric circulation, we experienced a rare case of CA compression syndrome which was caused by acute type B aortic dissection. The principal symptom was severe epigastric pain that was refractory to medicinal treatment. The angiogram showed absence of the anatomically well-developed collateral pathways between the CA and the superior mesenteric artery. We treated the patient with percutaneous transluminal angioplasty in the CA. This report indicates that attention should be given to the possibility of CA compression syndrome in the case of acute distal aortic dissection and that endovascular management can be successfully applied to control symptoms caused by the syndrome, which is otherwise extremely difficult to repair directly by surgery.

Stent-Grafts in Patients With Marfan Syndrome

To explore the safety and feasibility of stent-graft placement in the dissected descending thoracic aorta of patients with Marfan syndrome. Six consecutive patients (4 men; mean age 33+/-15 years, range 24-61) with Marfan syndrome were offered endovascular repair for dissection after previous aortic root repair in 5 and solitary type B dissection in 1. Transluminal placement of customized Talent stent-grafts was technically successful in all patients, with no 30-day or 1-year intervention-related mortality. Complete abolition of the dissection and reconstruction of the entire dissected aorta was documented in 2 patients. Over a mean 51+/-22-month follow-up (range 12-74), elective conversion to surgical repair was necessary in 2 patients at 22 and 43 months after stent-graft implantation. In a third patient, conversion to surgery is being considered at 74 months after stent-grafting. One patient died suddenly 12 months after endovascular repair. Nonsurgical reconstruction of postsurgical distal aortic dissection in patients with Marfan syndrome is feasible and technically successful. Stent-graft placement may either avoid or bridge to repeat surgery of distal aortic dissections after previous aortic root repair. Technical expertise and close postinterventional surveillance appear mandatory and may limit the procedure to centers of competence for aortic diseases.

Twenty-year experience with acute distal thoracic aortic dissections

Background There are few large studies in the literature that document the clinical outcome of an acute dissection of the distal thoracic aorta (ADDA), particularly since the advent of percutaneous techniques for therapeutic and prophylactic treatment of complications of ADDA. The goal of this study was to evaluate the outcome of ADDA with respect to medical, surgical, and percutaneous treatment over a 20-year period, and to use this information to estimate the benefit that future prophylactic therapy may yield. Methods The hospital records of all patients admitted with ADDA during the period of the study were reviewed retrospectively. Results There were 119 patients who fit the criteria of ADDA. Medical management was performed in 92 patients, with an overall mortality in this group of 13% (12/92 patients). Major morbidity occurred in 34 of the 83 surviving patients managed nonoperatively. Percutaneous interventions consisting of aortic fenestration and branch vessel stenting in 5 patients had a mortality rate of 40% and was only effective in the treatment of isolated renal artery malperfusion. Twenty-two patients underwent aortic surgery for complications or risk of impending rupture. Postoperative mortality was 18% (4/22 patients). Significant risk factors for death were rupture, acute renal failure, mesenteric ischemia, and age >70. No patient who had surgical fenestration required reoperation on the tailored segment. On the basis of clinical outcomes, we estimate that a maximum of 37% of patients could benefit acutely from prophylactic treatment of ADDA with aortic stent grafts, and an additional 13% could benefit chronically from such prophylactic treatment. Conclusions ADDA remains a challenging clinical problem with many failures of medical, surgical, and percutaneous therapy. Surgery remains an effective therapeutic option in the treatment of complications of acute dissection of the distal thoracic aorta, and surgical aortic fenestration is a durable treatment for malperfusion. A minority of patients may benefit from prophylactic treatment of ADDA with thoracic stent grafts.

Serum C-reactive protein elevation predicts poor clinical outcome in patients with distal type acute aortic dissection: association with the occurrence of oxygenation impairment

Background Acute aortic dissection (AAD) is sometimes complicated by respiratory failure due to severe lung oxygenation impairment. Systemic activation of inflammatory system after aortic injury may play some roles in the development of this complication. The aim of this study was to determine the significance of serum C-reactive protein (CRP) elevation in the development of oxygenation impairment and clinical outcome with distal type AAD. Methods and results A total of 61 patients, who were admitted with distal type AAD within 24 h from the onset, were examined. Serum CRP levels, white blood cell (WBC) counts and body temperature were measured serially for at least 4 days. Oxygenation impairment, defined as the lowest PaO 2/FIO 2 ratio ≤200 mmHg, was noted in 31 patients (51%). In patients with oxygenation impairment, peak CRP levels (20.7±7.9 vs. 12.7±3.8 mg/dl, P<0.001), peak WBC counts (14,600±3600 vs. 11,800±4300/mm 3, P=0.008) and body temperature (38.4±0.5 vs. 38.0±0.6 °C, P=0.004) were significantly higher than those without. Peak CRP level was inversely correlated with the lowest PaO 2/FIO 2 ( P<0.001). Patients who underwent urgent surgical treatment and/or died in the hospital had higher peak CRP levels (25.1±12.3 vs. 16.1±7.4 mg/dl, P=0.010) than those who did not. Multivariate analysis revealed that a peak CRP level ≥15 mg/dl (relative risk=12.6, P<0.001) was an independent determinant of the development of oxygenation impairment. Conclusion The greater serum CRP elevation after distal type AAD was associated with a higher incidence of oxygenation impairment and poor clinical outcome. Systemic activation of the inflammatory system after aortic injury may play an important role in the development of oxygenation impairment.

Acute Aortic Dissection Presenting as Rupture of the Femoral Artery

A 44-year-old male with Marfan's disease presented acutely with severe chest and left groin pain. A pulsatile mass was present in the left groin and the left leg was pale and pulseless. CT imaging demonstrated the presence of a distal thoracic aortic dissection (AD) involving the left iliofemoral segment with extravasation of contrast into the left groin. The patient was treated with an urgent femoral-femoral bypass, which repaired the femoral artery and restored perfusion to the left lower extremity. Whereas rupture of the aorta into the chest or pericardium is common, femoral artery rupture complicating AD has not been previously reported. This case illustrates the need for peripheral branch intervention when compromised by the dissection process including isolated iliofemoral segments, which are typically benign. Given frank femoral artery rupture, urgent surgical repair was required and resulted in a satisfactory outcome.

CT in nontraumatic acute thoracic aortic disease: typical and atypical features and complications.

Thoracic aortic dissection is the most frequent cause of aortic emergency, and unless it is rapidly diagnosed and treated, the result is death. Helical computed tomography (CT) permits the diagnosis of acute aortic dissection with a sensitivity and specificity of nearly 100%. This imaging modality also enables differentiation between proximal aortic dissection (type A in the Stanford classification) and distal aortic dissection (Stanford type B), which are treated differently and have different prognoses. In 70% of patients in whom nontraumatic acute thoracic aortic dissection is diagnosed after evaluation with helical CT, scans show the typical signs of aortic dissection, with rupture and displacement of the intima. CT also can depict other pathologic entities with similar clinical manifestations, such as intramural hematoma and penetrating atherosclerotic ulcer. Awareness of the different radiologic appearances of these disease entities is essential for differential diagnosis. More than one-third of patients with aortic dissection show signs and symptoms indicative of systemic involvement. Because branch-vessel involvement may increase morbidity and mortality, in this group of patients it is important to evaluate the entire aorta so as to determine the distal extent of the dissection and detect any systemic involvement.