Acute Type B Aortic Dissection Research Articles

Invited Commentary

Despite recent advances made in the knowledge of the natural history and prognosis of acute type B aortic dissection (ABAD), many questions still linger. In this way, the International Registry of Acute Aortic Dissection (IRAD) comprises a unique source of vital information that definitely is helping understand the long-term outcomes of such patients. In this cohort analysis [1Jonker F.H.W. Trimarchi S. Rampoldi V. et al.Aortic expansion after acute type B aortic dissection.Ann Thorac Surg. 2012; 94: 1223-1229Abstract Full Text Full Text PDF PubMed Scopus (76) Google Scholar], the findings are relevant and with likely straight clinical implications. The unexpected observation that patients with smaller aortas (aortic diameter <4 cm) exhibited increased aortic expansion over time compared to those with larger aortas (diameter ≥4 cm) still warrants a reasonable explanation, but going forward we must remember that those patients should be watched closely and more cautiously than previously thought. The use of calcium channel blockers was consistently able to retard the aorta diameter enlargement in the long-run; therefore, it has been a promising novel and important tool in our armamentarium for treating these patients. This information is in consonance with and strengthens previous publication [2Suzuki T. Isselbacher E.M. Nienaber C.A. et al.Type-selective benefits of medications in treatment of acute aortic dissection (from the International Registry of Acute Aortic Dissection [IRAD]).Am J Cardiol. 2012; 109: 122-127Abstract Full Text Full Text PDF PubMed Scopus (141) Google Scholar] in which calcium channel blockers was independently associated with improved survival during follow-up among the IRAD cohort of ABAD patients. Furthermore, some findings challenge data from prior reports. The prognostic implications of false lumen partial thrombosis have been an object of controversy and a previous study from IRAD found this entity a significant predictor of postdischarge mortality, compared with false lumen patency [3Tsai T.T. Evangelista A. Nienaber C.A. et al.Partial thrombosis of the false lumen in patients with acute type B aortic dissection.N Engl J Med. 2007; 357: 349-359Crossref PubMed Scopus (525) Google Scholar]. However, this finding has been contradicted by the data presented herein, not confirming the higher mortality related to the increased aortic expansion among these patients. The possible increased follow-up mortality for those patients with partial false lumen thrombosis remains open and unexplained; therefore, further research is needed about its effect on the prognosis of ABAD. Aortic Expansion After Acute Type B Aortic DissectionThe Annals of Thoracic SurgeryVol. 94Issue 4PreviewA considerable number of patients with acute type B aortic dissection (ABAD) treated with medical management alone will exhibit aortic enlargement during follow-up, which could lead to aortic aneurysm and rupture. The purpose of this study was to investigate predictors of aortic expansion among ABAD patients enrolled in the International Registry of Acute Aortic Dissection. Full-Text PDF

The Complications of Uncomplicated Acute Type-B Dissection: The Introduction of the Penn Classification

Uncomplicated acute type-B aortic dissection (ATBAD) is a misnomer because it has subgroups with excessive mortality risk. The Penn classification has designated these ATBAD presentations as class-A because they initially are characterized by the absence of malperfusion and/or aortic rupture. The Penn classification also has designated class-A high-risk subgroups as type I and low-risk subgroups as type II. The risk factors for Penn class-A type-I presentations relate to medical therapy; aortic anatomy, and dissection extent as outlined by the DeBakey classification. Tight medical therapy significantly protects against aortic complications. Beta-blockade, angiotensin inhibition, and calcium channel antagonists may reduce mortality. The details of optimal medical therapy require further research. The aortic risk factors for type-I presentations include false lumen size and patency, ulcer-like projections, aortic diameter >40 mm, and intimal tear characteristics such as size and proximal location. The prognostic role of dissection extent in ATBAD remains unclear, requiring further investigation to determine its effect on natural history. Future trials in Penn class-A ATBAD should focus on type-I presentations. The Penn classification can serve as a clinical framework for trial design, laying the groundwork for future management advances. It also may provide a common language to facilitate standardized definitions, trial design, and management approaches for this high-risk patient cohort.

Aortic Expansion After Acute Type B Aortic Dissection

A considerable number of patients with acute type B aortic dissection (ABAD) treated with medical management alone will exhibit aortic enlargement during follow-up, which could lead to aortic aneurysm and rupture. The purpose of this study was to investigate predictors of aortic expansion among ABAD patients enrolled in the International Registry of Acute Aortic Dissection. We analyzed 191 ABAD patients treated with medical therapy alone enrolled in the registry between 1996 and 2010, with available descending aortic diameter measurements at admission and during follow-up. The annual aortic expansion rate was calculated for all patients, and multivariate regression analysis was used to investigate factors affecting the expansion rate. Aortic expansion was observed in 59% of ABAD patients; mean expansion rate was 1.7±7 mm/y. In multivariate analysis, white race (regression coefficient [RC], 4.6; 95% confidence interval [CI], 1.4 to 7.7) and an initial aortic diameter less than 4.0 cm (RC, 6.3; 95% CI, 4.0 to 8.6) were associated with increased aortic expansion. Female sex (RC, -3.8; 95% CI, -6.1 to -1.4), intramural hematoma (RC, -3.8; 95% CI, -6.5 to -1.1), and use of calcium-channel blockers (RC, -3.8; 95% CI, -6.2 to -1.3) were associated with decreased aortic expansion. White race and a small initial aortic diameter were associated with increased aortic expansion during follow-up, and decreased aortic expansion was observed among women, patients with intramural hematoma, and those on calcium-channel blockers. These data raise the possibility that the use of calcium-channel blockers after ABAD may reduce the rate of aortic expansion, and therefore further investigation is warranted.

Acute type B aortic dissection in the absence of aortic dilatation

Increasing aortic diameter is thought to be an important risk factor for acute type B aortic dissection (ABAD). However, some patients develop ABAD in the absence of aortic dilatation. In this report, we sought to characterize ABAD patients who presented with a descending thoracic aortic diameter <3.5 cm. We categorized 613 ABAD patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2009 according to the aortic diameter <3.5 cm (group 1) and ≥3.5 cm (group 2). Demographics, clinical presentation, management, and outcomes of the two groups were compared. Overall, 21.2% (n = 130) had an aortic diameter <3.5 cm. Patients in group 1 were younger (60.5 vs 64.0 years; P = .015) and more frequently female (50.8% vs 28.6%; P < .001). They presented more often with diabetes (10.9% vs 5.9%; P = .050), history of catheterization (17.0% vs 6.7%; P = .001), and coronary artery bypass grafting (9.7% vs 3.4%; P = .004). Marfan syndrome was equally distributed in the two groups. The overall in-hospital mortality did not differ between groups 1 and 2 (7.6% vs 10.1%; P = .39). About one-fifth of patients with ABAD do not present with any aortic dilatation. These patients are more frequently females and younger, when compared with patients with aortic dilatation. This report is an initial investigation to clinically characterize this cohort, and further research is needed to identify risk factors for aortic dissection in the absence of aortic dilatation.

Simultaneous endovascular stent and renal stent placement for acute type B aortic dissection with malperfusion of kidney

Acute aortic dissection frequently causes life-threatening organ ischemia. The optimal therapy for acute type-B aortic dissection is still controversial. Surgery for acute dissection with organ malperfusion is known to carry a high morbidity and mortality; however endovascular treatment is becoming an alternative form of treatment. We report a clinical case of emergency percutaneous thoracal aorta endovascular stenting and renal artery stenting in a patient who had renal malperfusion and acute renal failure due to acute type-B dissection. The present case is a fundamental examples of collaboration between the cardiologist and cardiovascular surgeon in a hybrid procedure.

Endovascular Stent-Graft Placement or Open Surgery for the Treatment of Acute Type B Aortic Dissection: A Meta-Analysis

Acute type B aortic dissection (ATBAD) is a life-threatening condition. Open chest surgical repair using a prosthetic graft has been a conventional treatment for ATBAD. During the past decade, thoracic endovascular aortic repair (TEVAR), which is considered as a less invasive and potentially safer technique, has been increasingly used to treat this condition. Evidence is needed to support the use of TEVAR for these patients. The aim of this review was to assess the efficacy of TEVAR versus conventional open surgery in patients with ATBAD. For this review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (last searched: 2010, issue 4), MEDLINE, EMBASE, CINAHL, Web of Science, and the Chinese Biomedicine Database for clinical trials until January 18, 2011. Controlled trials in which patients with ATBAD were assigned to TEVAR or open surgical repair were included. For each outcome, we evaluated the quality of the evidence with reference to the Grading of Recommendations Assessments, Development, and Evaluation criteria. At the end, we used RevMan 5.0 software to analyze the datum. Five trials (318 participants) are included in this review. As determined by the Grading of Recommendations Assessments, Development, and Evaluation approach, the result quality was low for 30-day mortality and very low for other variables. TEVAR can significantly reduce the short-term mortality for ATBAD (Mantel-Haenszel fixed odds ratio [95% confidence interval]: 0.19 [0.09-0.39], P < 0.001). TEVAR cannot significantly improve postoperative complications or long-term mortality. TEVAR can be weakly recommended as an alternative for the selective treatment of ATBAD but cannot always be used in case of surgery.

Endovascular Repair of Complicated Acute Type-B Aortic Dissection with Stentgraft: Early and Mid-term Results

Endovascular Repair of Complicated Acute Type-B Aortic Dissection with Stentgraft: Early and Mid-term Results

A novel technique for renal stenting in the setting of type‐B aortic dissection

A type-B acute aortic dissection patient required renal artery revascularization for renal artery stenosis resulting from the compression by a false lumen. Renal artery stenting was complicated by unclear opacification of the ostia resulting from the collapsed true lumen of both renal artery and aorta. The use of the "Szabo" technique facilitated this procedure by allowing us to position the stent edge precisely at the ostium. This is the first report of this technique utilized in this lesion subset.

Acute Type B Dissection: Intervention for Rupture or Impending Rupture

Objective: Operative procedures for acute type B aortic dissection (ABAD) are usually performed in the setting of complications. This study focuses on outcomes for repair of ABAD for indications of rupture or impending rupture. Methods: Of the 383 patients admitted with ABAD (1995-2010), 41 (10.7%) underwent open (DTAR, 18) or endovascular aortic repair (TEVAR, 23) for rupture or impending rupture at a median of 3.5 days following presentation. Indications for intervention included rupture (17) or factors portending rupture including rapid expansion (11), uncontrolled pain (13), aortic size >5.0 cm (13) or refractory hypertension (2). 11 patients had multiple indications. Isolated intramural hematoma was present in 10. Extent of repair included arch (32, 78%) or total descending aorta (16, 39%). Selection of therapy was based upon age and extent of comorbidities. TEVAR, though available since 1993, was preferentially used since 2007. Patients undergoing TEVAR were older and more frequently had prior MI, renal failure, tobacco use history, or Debakey IIIA ABAD (all P < .05). Results: 30-day mortality was 17% (n = 7). Morbidity included stroke (3), renal failure needing dialysis (3), or permanent paraplegia (3). Independent correlates of a composite outcome of mortality and these morbidities included presentation with rupture (P = .02, OR 7.6) or active tobacco use (P = .02, OR 9.8), but not treatment strategy (P = .18). 8 yr Kaplan-Meier survival was 49.4%. Independent predictors of late mortality included occurrence of perioperative stroke or presentation with aortic rupture during late follow-up (both P < .002). 8 yr freedom from aortic rupture or reintervention was 76.6%. When compared to open repair, TEVAR had a similar late survival (3 yr 67.1% vs. DTAR 72.2%, log rank P = .8), and rate of false lumen thrombosis (P = .56). 3 yr freedom from aortic reintervention or rupture was higher after open repair (DTAR 94% vs. TEVAR 61%, log rank P = .16). Conclusion: Intervention for acute type B dissection complicated by rupture or impending rupture remains associated with significant rates of early and late morbidity and reintervention. Understanding the baseline differences in the treatment groups presented in this study, these data support the use of an endovascular approach for this indication in acute dissection.

Endovascular Repair of Complicated Acute Type-B Aortic Dissection with Stentgraft: Early and Mid-term Results

Endovascular Repair of Complicated Acute Type-B Aortic Dissection with Stentgraft: Early and Mid-term Results

Endovascular Repair of Complicated Acute Type-B Aortic Dissection with Stentgraft: Early and Mid-term Results

Objectives To analyse the experience of a single centre and evaluate the early and mid-term results of endovascular repair of complicated acute type B aortic dissection with stentgrafts. Method From July 2002 to January 2009, 45 patients (12 women, 33 men) with complicated acute type B aortic dissection (mean age, 42.6 years; range, 31–47 years) were treated with Thoracic Endovascular Aortic Repair (TEVAR). Indications for treatment included rupture in 6(13%), hemathorax with impending rupture in 27(60%), malperfusion syndrome in 11 (22%), and transient paraplegia in one patient (2.2%). Five kinds of commercially available thoracic stentgrafts were used. Follow up was 100% during a period of 13 months (range, 1–36 months). Results Technical success (coverage of the primary tear site) was achieved in all 45 patients(100%) including deliberate partial or total coverage of the LSA in 7 patients (15.6%). The 30-day and in-hospital mortality was 4.4% including one late rupture case. Overall survival was 95.6% at 1 and 3-years’ follow-up. None of the patients with malperfusion required adjunct distal stents All hemothoces resolved within 3 months including 5 patient required thoracentesis and one had tube thoracostomy. And 7 patients required temporary dialysis In-hospital complications occurred in 26.7% of patients and re-intervention was required in one patient and no patient had postoperative paraplegia Postoperative CT angiography showed 25 patients (58.1%) with complete thrombosis of the false lumen and re-expansion of the true lumen. Conclusions Endovascular repair of complicated acute type B aortic dissection with stentgraft is proven to be a technically feasible and effective in this relatively difficult patient cohort, The short and mid-term efficacy are persuasive, however, the long-term efficacy needs to be evaluated further.

Emergent Thoracic Endovascular Aortic Repair forAcute Type-B Aortic Dissection with Malperfusionby Matsui-Kitamura Stent Graft

Acute type-B aortic dissection with malperfusion is a serious cardiovascular condition associated with high morbidity and mortality. Recent studies have investigated the efficacy of thoracic endovascular aortic repair (TEVAR) as treatment for acute aortic dissection. In this report, we present a case of acute type-B aortic dissection complicated with malperfusion, which was successfully treated with emergent TEVAR for entry closure by a Matsui-Kitamura stent graft (MKSG). MKSG is a flexible custom-made curved stent graft. The main advantages of MKSG for emergent TEVAR include flexibility, shape, and small profile when compressed.

Clinical Summaries

Clinical Summaries

Long-term outcomes of surgical aortic fenestration for complicated acute type B aortic dissections

Surgical aortic fenestration has been used for treating ischemic complications of acute type B aortic dissection (ABAD). In the current endovascular era, surgical aortic fenestration may serve as an alternative for these patients after percutaneous failure. The purpose of this study is to describe our surgical suprarenal and infrarenal aortic fenestration technique, and to report the long-term outcomes of this approach in the management of complicated ABAD. We retrospectively analyzed the in-hospital and long-term outcomes of 18 patients treated with either suprarenal (n = 10) or infrarenal surgical fenestration (n = 8) for complicated ABAD between 1988 and 2002. Suprarenal fenestration was performed through a thoracoabdominal incision in the 10th intercostal space, whereas patients treated with infrarenal fenestration underwent a midline laparotomy. A longitudinal aortotomy was performed and the true and false lumens were identified, followed by a wide resection of the intimal membrane. Median age was 60 years (range, 48-82 years) and 89% (n = 16) were male. The in-hospital mortality was 22% (n = 4), which included two deaths after suprarenal fenestration and two deaths after infrarenal fenestration. In the remaining patients, full visceral, renal, and lower extremity function was recovered, except for 1 patient with paraplegia at admission in which the neurologic deficit was permanent. Median follow-up of the surviving patients was 10.0 years (interquartile range, 12.5; range, 0.5-20 years). During follow-up, none of the patients developed renal or visceral ischemia, or ischemic complications to the lower extremities, and no significant dilatations of the treated aortic segments were noted. Three of 14 patients with ABAD who were discharged alive expired during the follow-up period due to causes unrelated to the surgical procedure. Surgical aortic fenestration represents an effective and durable option for treating ischemic complications of ABAD. Actually, this conservative surgical technique may serve as the alternative treatment in case of contraindications or failure of endovascular management of complicated ABAD.

Outcome of patients suffering from acute type B aortic dissection: a retrospective single-centre analysis of 135 consecutive patients☆

Acute uncomplicated Stanford type B aortic dissection (TBAD) is optimally managed with medical treatment. However, surgery and thoracic endovascular aortic repair (TEVAR) are occasionally indicated, particularly when end-organ ischaemia develops. This study assesses the perioperative and long-term outcomes of medical, interventional and surgical management of acute TBAD. A total of 135 consecutive patients with acute TBAD treated at our institution between 2000 and 2008 were analysed. Of these patients, 84 were treated medically (group A, median age: 65 years, interquartile range (IQR): 34-90), 46 patients received TEVAR (group B, median age: 65, IQR: 23-83) and five patients underwent open surgical management (group C, median age: 60 years, IQR: 44-69). Clinical data and information on complications, re-intervention and acute and long-term mortality were retrospectively collected and examined. Follow-up was made on 98% of patients with a median time span of 1107 days (IQR: 870-1343). There were no significant differences in age, gender, body mass index or co-morbidities among the three treatment groups. Group B patients had the highest rate of ruptures (n=7) and impending ruptures (n=19). Indications for surgery in group C were impending rupture with malperfusion (n=1), rupture (n=2) and refractory pain (n=2). The maximal diameter of dissection was significantly higher in group C (mean: 52.6mm, IQR: 36-82, p<0.05) than in group B (mean: 42.0mm, IQR: 20-74) and group A (mean: 40.6, IQR: 23-66). The 30-day and 5-year mortality rates, respectively, were 8.5% and 27.9% for group A, 20.0% and 43.7% for group B (p=0.018 for group A) and 20.0% for both time points for group C patients. The rate of re-intervention was significantly higher in group A (A: 22/84, 26.2% vs B: 8/46, 17.4%; p=0.049, and group C: 1/5, 20%). The rate of major complications (e.g., stroke, paraplegia and/or vascular problems) did not differ among groups. Medical, interventional and surgical management for acute TBAD result in acceptable survival rates. Although stent implantation and surgery were reserved for patients with complications of TBAD in the current study, results were good for both treatment modalities. Randomised prospective trials should be performed to determine whether conservative, TEVAR or surgical management is most advantageous for complicated acute TBAD patients.

Endovascular Repair of Stanford Type B Aortic Dissection: Early and Mid-term Outcomes of 121 Cases

Objective: To analyse the early and mid-term outcomes of endovascular repair of Stanford type B aortic dissection (B-AD) and to compare the outcomes between acute type B aortic dissection (AAD) and chronic type B aortic dissection (CAD). Methods: The cohort included 121 consecutive patients undergoing endovascular repair for AAD (group A, n = 72) and CAD (group B, n = 49) between January 2001 and December 2006. Follow-up with clinical examinations and computed tomography (CT) was performed post-intervention at 1, 6 and 12 months, and then yearly thereafter. Results: In groups A and B, respectively, the procedure success rates were 88.9% and 77.6%; the rates of postoperative endoleak were 11.1% and 22.4%; the 30-day mortality rates were 1.4% and 8.2%; and the 30-day stroke rates were 4.2% and 2.0%. No postoperative spinal cord ischaemia (SCI) was observed. The mean follow-up periods for groups A and B were 14.4 ± 11.0 months and 22.1 ± 20.8 months, respectively. Late mortality was 1.5% in group A and 4.8% in group B. In group A, the rates of complete false lumen (FL) thrombosis at 1 month, 1 year and 2 years postoperatively were 32.3%, 51.4% and 53.8%, respectively, and in group B, 26.2%, 44.8%, and 50.0%, respectively. Conclusion: Endovascular repair is feasible for both AAD and CAD, with favourable short- and mid-term outcomes.

Endovascular Repair of Stanford Type B Aortic Dissection: Early and Mid-term Outcomes of 121 Cases

To analyse the early and mid-term outcomes of endovascular repair of Stanford type B aortic dissection (B-AD) and to compare the outcomes between acute type B aortic dissection (AAD) and chronic type B aortic dissection (CAD). The cohort included 121 consecutive patients undergoing endovascular repair for AAD (group A, n=72) and CAD (group B, n=49) between January 2001 and December 2006. Follow-up with clinical examinations and computed tomography (CT) was performed post-intervention at 1, 6 and 12 months, and then yearly thereafter. In groups A and B, respectively, the procedure success rates were 88.9% and 77.6%; the rates of postoperative endoleak were 11.1% and 22.4%; the 30-day mortality rates were 1.4% and 8.2%; and the 30-day stroke rates were 4.2% and 2.0%. No postoperative spinal cord ischaemia (SCI) was observed. The mean follow-up periods for groups A and B were 14.4+/-11.0 months and 22.1+/-20.8 months, respectively. Late mortality was 1.5% in group A and 4.8% in group B. In group A, the rates of complete false lumen (FL) thrombosis at 1 month, 1 year and 2 years postoperatively were 32.3%, 51.4% and 53.8%, respectively, and in group B, 26.2%, 44.8%, and 50.0%, respectively. Endovascular repair is feasible for both AAD and CAD, with favourable short- and mid-term outcomes.

Endovascular stent placement for acute type-B aortic dissection with malperfusion - an intentional surgical delay and a possible 'bridging therapy'

Acute aortic dissection frequently causes life-threatening organ ischemia. The optimal therapy for acute type-B aortic dissection is still controversial. Early surgery for acute dissections with organ malperfusion is known to carry a high morbidity and mortality. Endovascular treatment, such as stent placement for branch stenosis, percutaneous balloon fenestration for compression of the true channel and aortic stent placement to support collapsed true channel, is becoming an alternative form of treatment. However, it is not clear whether endovascular intervention alone is effective in the long term. We herein report a case of emergency percutaneous endovascular stenting with intentional surgical delay in a patient who had visceral and lower extremity malperfusion due to acute type-B dissection. A 10x57 mm bare metal stent was inserted into the obliterated true channel of the thoracoabdominal aorta 3 h after onset of symptoms. It immediately relieved the abdominal and lower limb ischemic symptoms. The advantage of small-sized stent placement is its easiness and being gentle to fragile intima. The small-sized stent placement for patients with acute aortic dissection with visceral organ ischemia may be a promising 'bridging therapy' before they undergo traditional central repair.

Evaluation of volumetric measurements in patients with acute type B aortic dissection – thoracic endovascular aortic repair (TEVAR) vs conservative

The aim of this retrospective study was to evaluate aortic volume changes in patients with acute type B aortic dissection (TBD), treated either by thoracic endovascular aortic repair (TEVAR) or conservatively. From July 1996 through March 2008, 76 patients presenting with acute TBD were referred to our department. To ensure a follow-up of at least 24 months, only 64 of them were included in the present study, with the cut-off for inclusion being March 2006. Twenty-nine of these patients underwent TEVAR and 35 patients underwent conservative treatment. Indications for TEVAR were life-threatening symptoms. Follow-up was performed postinterventionally in patients after TEVAR and at 3, 6, and 12 months, and yearly thereafter in both groups. It included clinical examinations, computed tomography (CT) scans, analysis of volume changes in true thoracic lumen (TTL), false thoracic lumen (FTL), thoracic lumen (TL), abdominal lumen (AL), and aortic diameter measurements. In addition, the extent of thrombosis and its influence on volume changes were assessed. Mean follow-up was 41 months after TEVAR and 46 months in the conservatively-treated patients. At 60 months, cumulative rates of freedom from dissection-related death and rupture-free survival were 82.6% and 93.1% in the TEVAR group, respectively. They were 74.9% and 88.5% in the conservatively-treated group, respectively. In the conservatively-treated patients, 3 patients died of late aortic rupture, 4 were converted to open surgery, and 2 to TEVAR. Evaluation of volume changes showed better results in the TEVAR group within 24 months. However, within 60 months the difference between the two groups was no longer relevant. Relating to thrombosis of the FTL, analyses showed slightly better overall results and promotion of thrombus formation after TEVAR. However, at 60 months the results showed a tendency towards approximation between the two groups. Our data suggest that TEVAR seems to delay the natural course of the disease but not to stop it.

Acute Type B Aortic Dissection: Does Aortic Arch Involvement Affect Management and Outcomes?

Stanford Type B acute aortic dissection (TB-AAD) spares the ascending aorta and is optimally managed with medical therapy in the absence of complications. However, the treatment of TB-AAD with aortic arch involvement (AAI) remains an unresolved issue. We examined 498 patients with TB-AAD enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. Kaplan-Meier mortality curves were constructed and multivariate regression models were performed to identify independent predictors of AAI and to evaluate whether AAI was an independent predictor of follow-up mortality. We found that 371 (74.5%) patients with TB-AAD did not have AAI versus 127 (25.5%) with AAI. Independent predictors of AAI were a history of previous aortic surgery (OR 3.4; 95% CI, 1.6 to 7.6; P=0.002), absence of back pain (OR 1.6; 95% CI, 1.1 to 2.5; P=0.05), and any pulse deficit (1.9; 95% CI, 1.1 to 3.3, P=0.03). Mortality for patients without AAI was 9.4%+/-4.3% and 21.0%+/-6.9% at 1 and 3 years versus 9.2%+/-7.7% and 19.9%+/-11.1% with AAI, respectively (mean follow-up overall, 2.3 years, log rank P=0.82). AAI was not an independent predictor of long-term mortality. Patients with TB-AAD and aortic arch involvement do not differ with regards to mortality at 3 years. Whether or not AAI involvement impacts other measures of morbidity such as freedom from operation or endovascular intervention deserves further study.