Selective management of acute type B aortic dissection: long-term follow-up

Methods and outcomes of endovascular false lumen embolization for thoracic aortic dissection

PURPOSE

To provide a contemporary review on endovascular false lumen (FL) embolization for thoracic aortic dissection (AD) and evaluate its early outcome.

METHODS

A systematic literature review on FL embolization for thoracic AD from January 2003 to December 2020 was performed under the instruction of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. Each article was analyzed using a standardized protocol including predefined demographic characteristics, perioperative mortality and major complications.

RESULTS

A total of 29 papers with 229 patients were included into the analysis. The methods of FL occlusion used were: the Candy-Plug technique, the knickerbocker technique, the "cork in the bottleneck" technique and direct FL embolization with combination of stent-grafts, coils, onyx, plugs and glue. FL embolization procedure was performed in 79 patients (34.5%) with type A AD and 150 (65.5%) with type B AD. FL direct embolization was the most frequently used technique, and it was applied in 198 (86.5%) patients. Candy-plug, knickerbocker and "cork in the bottleneck" techniques were used in 26 (11.4%), 3 (1.3%) and 2 (0.9%) patients, respectively. Technical success was achieved in all patients except one (228/229, 99.6%) in which implantation of a stent to celiac trunk was not possible. There were four hospital deaths (1.7%). Neurological complications occurred in 6 patients (2.6%), including 4 (1.7%) spinal cord ischemia and 2 (0.9%) ischemic stroke. There were 1 (0.4%) iatrogenic retrograde dissection and 2 (0.9%) renal failure reported. The mean duration of follow-up was 16.5 months. There were 21 deaths (9.3%) during follow-up, and 8 (3.6%) were aorta-related. Thirty-three (14.7%) secondary intervention were performed. Five patients (2.2%) required open completion thoracoabdominal procedure incorporating the stent-graft into the repair. Complete FL thrombosis was observed in 181 (80.4%) patients, 34 (15.1%) had partial thrombosis, and 10 (4.4%) had FL progression.

CONCLUSIONS

FL embolization of the distal thoracic aorta is a promising technique in a group of patients to promote FL thrombosis and aortic remodeling in thoracic aorta.

Outcomes of Thoracic Endovascular Aortic Repair in Octogenarians

OBJECTIVE

The aim of this study is to compare outcomes between octogenarians and non-octogenarians undergoing thoracic endovascular aortic repair (TEVAR).

METHODS

Using the National Inpatient Sample database, we identified octogenarians (≥80 years) and non-octogenarians (<80 years) who had undergone thoracic endovascular aortic repair between 2012 and 2017. We compared patients' demographic, socioeconomic, comorbidity data between the two groups as well as the procedure indications and perioperative outcomes. A multivariable logistic regression analysis was conducted to evaluate the impact of advanced age (≥80 years) on the in-hospital mortality rates in patients who underwent TEVAR. This analysis was also performed for a separate cohort which included only patients who underwent TEVAR for ruptured thoracic aortic aneurysm.

RESULTS

A total of 4108 patients were included in our study; 3432 (83.5%) patients were <80 years (37.9% female; median age, 64 years; 34.3% non-white) and 676 (16.5%) patients were ≥80 years (50.7% female; median age, 83 years; 20.4% non-white). Non-ruptured thoracic aortic aneurysm was the most common indication for TEVAR in older patients (61.4%), whereas type B aortic dissection was the most common indication in younger patients (36.4%). In-hospital complications were comparable between the two groups except for respiratory complications that were higher in the younger patients (21.2% vs. 15.2%; P <.001). The multivariable analysis demonstrated that advanced age had no association with increased in-hospital mortality rates (adjusted odds ratio [aOR], 1.41; 95% confidence interval [CI], .97-2.05), However, in ruptured thoracic aortic aneurysm cohort, octogenarians had higher in-hospital mortality rates (aOR, 1.86; 95% CI, 1.04-3.32).

CONCLUSIONS

Octogenarians have acceptable rates of perioperative morbidity and mortality compared to the younger group and should be considered for TEVAR. Octogenarians are at higher risk for in-hospital mortality in the setting of ruptured thoracic aortic aneurysm, supporting the appropriateness of elective TEVAR in selected Octogenarians.

Endovascular management of chronic post-dissection aneurysms

Open repair is still the gold standard in acute type A dissection. Endovascular repair is advocated for complicated acute type B dissections. Recent evidence also supports the role of endovascular repair in a larger proportion of uncomplicated acute type B dissections. The role of endovascular repair in chronic post-dissection aneurysms, however, is still unclear. Most commonly, post-dissection aneurysms involve the thoracoabdominal aorta, making the use of fenestrated/branched stent-grafts to achieve complete aneurysm exclusion mandatory. These fenestrated/branched stent-grafts have been used with success in atherosclerotic thoracoabdominal aortic aneurysms (TAAAs). In chronic post-dissection aneurysms, however, additional technical challenges arise. The usually narrow true lumen makes the use of branches more tedious and overall planning difficult. A second technical challenge relates to the fact that visceral branches can also originate from the false lumen. In such cases, perforation of the stiff chronic dissection flap is required to obtain access to the vessel. During the period January 2010 to November 2013, 17 patients (13 males, mean age 65±7.8 years) with chronic thoracoabdominal aneurismal degeneration following acute dissection were treated in our department with the use of fenestrated/branched stent-grafts. Technical success was achieved in all cases (100%). Perioperative mortality was two (11.8%) patients. One patient died due to multiple organ failure and one due to cardiac failure. No case of paraplegia was observed. During a 12-month median follow-up (range, 4-28 months) no aneurysm-related deaths were observed. Reintervention was required in three cases to repair a type Ib endoleak from a side branch. Endovascular treatment with fenestrated/branched stent-grafts is feasible for chronic post-dissection aneurysms. Standard thoracic stent-grafting is an option in a minority of patients, when the aneurysm is limited to the thoracic segment. Fenestrated and branched devices can successfully be used for aneurysms extending to the thoracoabdominal aorta.

Five-year results for endovascular repair of acute complicated type B aortic dissection

INTRODUCTION

Despite a current lack of U.S. Food and Drug Administration approval for the indication, thoracic endovascular aortic repair (TEVAR) has replaced open surgical management for acute complicated type B aortic dissection due to promising short- and midterm data. However, long-term results, with a view toward durability and need for secondary procedures, are limited. As such, the objective of the present study is to report long-term outcomes of TEVAR for acute (≤ 2 weeks from symptom onset) complicated type B dissection.

METHODS

Between July 2005 and September 2012, 50 consecutive patients underwent TEVAR for management of acute complicated type B dissection at a single referral institution. Patient records were retrospectively reviewed from a prospectively maintained clinical database.

RESULTS

Indications for intervention included rupture in 10 (20%), malperfusion in 24 (48%), and/or refractory pain/impending rupture in 17 (34%). One patient (2%) had both rupture and malperfusion indications. Ten (20%) patients required one or more adjunctive procedures, in addition to TEVAR, to treat malperfusion syndromes. In-hospital and 30-day rates of death were both 0%; 30-day/in-hospital rates of stroke, permanent paraplegia/paraparesis, and new-onset dialysis were 2% (n = 1), 2% (n = 1), and 4% (n = 2), respectively. Median follow-up was 33.8 months [interquartile range, 12.3-56.6 months]. Overall survival at 5 and 7 years was 84%, with no deaths attributable to aortic pathology. Thirteen (26%) patients required a total of 17 reinterventions over the study period for type I endoleak (n = 5), metachronous aortic pathology (n = 5), persistent false lumen pressurization via distal fenestrations (n = 4), type II endoleak (n = 2), or retrograde acute type A aortic dissection (n = 1). Median time to first reintervention was 4.5 months (range, 0 days-40.3 months). Of the 17 total reinterventions, six (35%) were performed using open techniques and 11 (65%) with endovascular or hybrid methods; there was no difference in survival between patients who did or did not require reintervention.

CONCLUSIONS

This study confirms the excellent short-term outcomes of TEVAR for acute complicated type B dissection and demonstrates the results to be durable and sustained over long-term follow-up. Although aortic reinterventions were required in one-quarter of patients, no aortic-related deaths were observed. These data support the use of TEVAR for acute complicated type B aortic dissection but also highlight the importance of life-long aortic surveillance by an experienced aortic referral center in order to identify and treat complications of the underlying disease process and treatment, as well as new aortic pathologies, as they arise.

Current evidence for thoracic aorta type B dissection management

Aortic dissection is a devastating cardiovascular condition and represents the most common aortic emergency. Outcome is determined by the type and extent of dissection and the presence of associated complications requiring early diagnosis and treatment. Aortic dissection is defined as acute within 14 days from onset and chronic after that time period. The natural course of type B dissection is determined by 2 elements, early and chronic complications. An uncomplicated acute type B dissection is less frequently lethal but it is not totally benign. Some peculiar issues must be taken into account, such as the high probability of complications development in a dissected aorta and the poor long-term prognosis on medical treatment alone. Then, it would be helpful to identify which patients with uncomplicated type B dissection will have a poorest aortic prognosis over time in order to apply an early intervention.

Acute aortic syndromes

Acute aortic syndrome is a term that describes one of a number of different pathologic entities. Each of these conditions requires urgent or emergent evaluation and may possibly require surgical intervention. However, both entities may be unfamiliar to the nonsurgical (and in some cases, surgical) practitioner and they may mimic more common diseases or be missed entirely. An understanding of the processes, nomenclature, and management options is critical in optimizing patient care.

Efficacy of thoracic endovascular stent repair for chronic type B aortic dissection with aneurysmal degeneration

BACKGROUND

The Food and Drug Administration has approved devices for endovascular management of thoracic endovascular aortic aneurysm repair (TEVAR); however, limited data exist describing the outcomes of TEVAR for aneurysms attributable to chronic type B aortic dissection (cTBAD). This study was undertaken to determine the results of endovascular treatment of cTBAD with aneurysmal degeneration.

METHODS

A retrospective analysis of all patients treated for cTBAD with aneurysmal degeneration at the University of Florida from 2004 to 2011 was performed. Computed tomograms with centerline reconstruction were analyzed to determine change in aortic diameter, relative proportions of aortic treatment lengths, and false lumen perfusion status. Reintervention and mortality were estimated using life-tables. Cox regression analysis was completed to predict mortality.

RESULTS

Eighty patients underwent TEVAR for aneurysm due to cTBAD (mean age [± standard deviation], 60 ± 13 years [male, 87.5%; n = 70]; median follow-up, 26 [range, 1-74] months). Median time from diagnosis of TBAD to TEVAR was 16 (range, 1-72) months. Prior aortic root/arch replacement had been performed in 29% (n = 23) at a median interval of 28.5 (range, 0.5-312) months. Mean preoperative aneurysm diameter was 62.0 ± 9.9 mm. In 75% (n = 60) of cases, coverage was proximal to zone 3, and 24% (n = 19) underwent carotid-subclavian bypass or other arch debranching procedure. Spinal drains were used in 78% (pre-op 71%, n = 57; post-op 6%, n = 5). Length of stay was 6.5 ± 4.7 days with a composite morbidity of 26% and in-hospital mortality of 2.5% (n = 2). Overall neurologic event rate was 17% (spinal cord ischemia 10% [n = 8], with a permanent deficit observed in 6.2% [n = 5]; stroke 7.5%). Aneurysm diameter reduced or stabilized in 65%. The false lumen thrombosed completely within the thoracic aorta in 52%, and reintervention within the treated aortic segment was required in 16% (n = 13).One- and 3-year freedom from reintervention (with 95% confidence interval [CI]) was 80% (range, 68%-88%) and 70% (range, 57%-80%), respectively. Survival at 1 and 5 years was 89% (range, 80%-94%) and 70% (range, 55%-81%) and was not significantly different among patients requiring reintervention or experiencing favorable aortic remodeling. Multivariable analysis identified coronary artery disease (hazard ratio [HR], 6.4; 95% CI, 2.3-17.7; P < .005), prior infrarenal aortic surgery (HR, 8.6; 95% CI, 2.3-31.7; P = .001), and congestive heart failure (HR, 11.9; 95% CI, 1.9-73.8; P = .008) as independent risk factors for mortality. Hyperlipidemia was found to be protective (HR, 0.2; 95% CI, 0.05-0.6; P = .004). No significant difference in predictors of mortality were found between patients who underwent reintervention vs those who did not (P = .2).

CONCLUSIONS

TEVAR for cTBAD with aneurysmal degeneration can be performed safely but spinal cord ischemia rates may be higher than previously reported. Liberal use of procedural adjuncts to reduce this complication, such as spinal drainage, is recommended. Reintervention is common, but long-term survival does not appear to be impacted by remediation.

Acute aortic dissection: an update

The aorta, which has a complex intrinsic biology and sophisticated mechanical properties for conducting the blood ejected from the left ventricle to the rest of the systemic arterial bed, is the largest and strongest artery in the body. It carries roughly 200 million liters of blood in an average lifetime. Any process that undermines the architecture threatens the structure, stability, and functionality of the aorta. In this regard, acute aortic dissection (AAD) requires special attention because it is the most catastrophic acute illness of the aorta; it has high morbidity and mortality because of potentially fatal complications. AAD has, therefore, become an important topic of recent research, and knowledge about this disease has improved during the past few years. Up-to-date knowledge about the natural history, epidemiology, presentation, physiopathology, evolution, management, follow-up, and long-term outcomes of AAD are summarized in this review.

Endovascular treatment of thoracic dissection

Type A aortic dissection remains fatal if untreated. Although classical medical therapy for type B dissection is considered the therapy of choice in uncomplicated cases, the paradigm is changing as greater experience is accrued with endovascular treatments and technical advances improve the long-term outlook. Diagnosis is also becoming more sophisticated, allowing greater appreciation of the anatomy of dissections and improving the knowledge base as their natural history is assessed.

Aortic dissection and rupture in a child

After developing sudden severe chest pain, an 11-year-old boy presented to the emergency room with chest pain and palpitations and was unable to stand up. The sudden onset of chest pain was first reported while swimming at school about 30 minutes prior to presentation. Arterial blood pressure (BP) was 150/90 mmHg, heart rate was 120/minute, and the chest pain was combined with shortness of breath and diaphoresis. During the evaluation in the emergency room, the chest pain worsened and abdominal pain developed. An aortic dissection was suspected and a chest and abdomen CT was obtained. The diagnosis of aortic dissection type B was established by CT imaging. The patient went to surgery immediately with BP control. He died prior to surgery due to aortic rupture. Here we present this rare case of aortic dissection type B with rupture, reported in an 11-year-old Korean child.

The effects of operative indication and urgency of intervention on patient outcomes after thoracic aortic endografting

BACKGROUND

Endovascular repair for complex thoracic aortic pathology has emerged over the past decade as an alternative to open surgical repair. Reports suggest lower morbidity and mortality rates associated with endovascular interventions. The purpose of this report was to analyze a large single institution experience in endovascular thoracic aortic repair based on clinical presentation as well as within and outside specific instructions for use.

METHODS

Records of all patients undergoing thoracic aortic endografting at our institution were retrospectively reviewed for demographics, interventional indications and acuity, operative details, and clinical outcomes. Study outcomes were analyzed by clinical presentation (urgent/emergent vs elective) and aneurysm morphology that was within and outside specific instructions for use as recommended by the manufacturer.

RESULTS

Between March 2006 and October 2009, 96 patients underwent thoracic endografting for aneurysm (n = 43), transection (n = 7), penetrating ulcer (n = 11), dissection (n = 19; acute = 9, chronic = 10), pseudoaneurysm (n = 11), or miscellaneous indications (n = 5). Endografting was performed with various endografts (Gore TAG: 59; Medtrontic Talent: 26; Zenith-TX2: 7; Combination: 4.Involvement of the arch (n = 42, 43.75%) was treated with subclavian artery coverage without revascularization in 13 (13.5%), debranching in 20 (20.8%), and fenestration/stenting in 9 (9.38%). Involvement of the visceral vessels (n = 24, 25%) was treated with debranching in 15 (15.6%) or fenestration/stenting in 9 (9.4%). Patients had a mean follow-up of 11.5 ± 10.96 (range: 0-38) months. Overall mortality was 6.25% (n = 6). Mean intensive care unit stay was 6.26 ± 8.55 (range: 1-63, median: 4) days, and hospital stay was 9.97 ± 10.31 (range: 1-65, median: 65) days. Major complications were infrequent and included: spinal cord ischemia (n = 6, 6.25%), stroke (n = 6, 6.25%), myocardial infarction (n = 3, 3.15%), renal failure (n = 6, 6.25%), and wound complications (n = 9, 9.38%). Reoperation was required in 13 (13.54%), with early intervention in 2 (2.1%). The vast majority of patients were discharged directly to home (n = 66, 68.8%). There were no significant differences between death (1/49 [2%] vs 5/47 [10.6%], P = .07), stroke (3/49 [6%] vs 3/47 [6%], P = 1.0), or spinal cord ischemia (3/49 [6%] vs 3/47 [6%], P = 1.0) when comparing urgent/emergent presentation to elective cases, respectively. However, there were significant differences in death (6/58 [10.5%] vs 0/38 [0%], P = .04) and spinal cord ischemia (6/58 [10.5%] vs 0/38 [0%], P = .04) but not stroke (5/58 [8.8%] vs 1/38 [2.5%], P = .24] when procedures were performed outside the specific instructions for use.

CONCLUSIONS

Results of this single-institution report suggest that endovascular thoracic aortic repair is a safe and effective treatment option for a variety of thoracic pathology including both elective and emergent cases. However, off-label usage of the devices is associated with a significantly higher risk of mortality and spinal cord ischemia, but the risk still appears acceptable given the majority of cases were emergent.

[Management of aortic dissection. Stent grafts for who?]

Acute aortic syndrome (AAS) describes several life threatening aortic pathologies. Acute aortic syndrome include intramural haematoma, penetrating aortic ulcer and acute aortic dissection. Advances in both imaging and endovascular treatment has led to an increase in diagnosis and improved management of these often catastrophic pathologies. The current place of stent-grafts for the AAS management is defined on the basis of the most recent literature.

Aortic dissection and rupture in an 11-year-old child: A case report

We present the case of an 11-year-old boy who developed sudden severe chest pain. When he was referred to the emergency department with this chest pain and palpitation, he could not even stand up. The sudden onset of chest pain was first complained about while he was swimming at school about 30 min previously. His arterial blood pressure was 150/90 mm Hg, heart rate was 120/min, and the chest pain was combined with shortness of breath and diaphoresis. During the evaluation in the emergency room, he complained of much severer chest pain and newly developed abdominal pain. We suspected aortic dissection and took computed tomography (CT) images of his chest and abdomen. The diagnosis of aortic dissection type B was established with the help of CT imaging. The patient went to surgery immediately with blood pressure control. He was lost before the operation because of aortic rupture. We report one rare case of aortic dissection type B with rupture in an eleven-year-old child in Korea.

Acute complicated and uncomplicated type III aortic dissection: an endovascular perspective

Type III aortic dissection is associated with high morbidity and mortality. There is a shifting paradigm in the treatment of complicated and uncomplicated acute type III aortic dissection toward earlier endovascular repair. In this review, the authors present the current perspective on the endovascular management of acute complicated and uncomplicated type III aortic dissection.

Endovascular therapy for thoracic aneurysm diseases: PRO

Although the long-term durability of stent grafts is still a concern, stent-graft treatment is already the best option in a large number of patients with descending thoracic aortic diseases who are poor candidates for surgical repair, or in an acute setting. With improved capability to recognize proper anatomy and select clinical candidates, the choice of endovascular stent-graft placement may offer a strategy to optimize management and improve prognosis.

Descending thoracic aortic dissections

Type B dissection has traditionally been managed medically if uncomplicated and surgically if associated with complications. This practice has resulted in most centers reporting significant morbidity and mortality if open repair is required. In the setting of malperfusion, operative repair has been conjoined with fenestration or visceral stenting to improve outcomes. Endovascular stent grafts seem to offer an attractive alternative in the acute complicated type B dissection, with reduced mortality and morbidity, particularly paralysis, compared with open repair. It is reasonable to consider endovascular stent grafts as another tool in managing dissection, but to recognize that open surgical repair still plays an important role, and that the data that define indications and outcomes are still emerging.

Thoracic aortic stent-graft devices: problems, failure modes, and applicability

Optimal treatment strategies for pathologies of the descending thoracic aorta are still controversial. Open surgery is complex, while endovascular devices allow nonsurgical access to the thoracic aorta. Endografts can be inserted via a peripheral artery while maintaining aortic blood flow without any need for clamping. Both short- and mid-term outcomes after endografting thoracic aneurysm and type B aortic dissection are encouraging, with significantly lower morbidity and early mortality compared with open surgery. However, despite emerging popularity and growing interest as an alternative to surgery, endograft design and manufacturing have not kept pace with growing clinical ambition. Major challenges associated with endovascular procedures using the current generation of endografts range from the relative rigidity and size of the delivery system to the failure of thoracic endografts to conform snugly to the anatomy of the aortic arch. Nonconformity of grafts may lead to graft instability, endoleak, and procedural failure. Current delivery systems are potentially traumatizing and, at times, too inflexible to track through tortuous, calcified vessels, and often require surgical exposure of the access vessel. Although efforts have been made by the industry to improve conformability and fixation in the aortic arch, given the spiraling movement of the thoracic aorta with each ventricular contraction, much work needs to be done on miniaturization and creation of disease-specific devices. The aim of this work is to give an overview on thoracic aortic stent-graft devices with focus on problems, failure modes and potential improvements.

Partial thrombosis of the false lumen in patients with acute type B aortic dissection

BACKGROUND

Patency or thrombosis of the false lumen in type B acute aortic dissection has been found to predict outcomes. The prognostic implications of partial thrombosis of the false lumen have not yet been elucidated.

METHODS

We examined 201 patients with type B acute aortic dissection who were enrolled in the International Registry of Acute Aortic Dissection between 1996 and 2003 and who survived to hospital discharge. Kaplan-Meier mortality curves were stratified according to the status of the false lumen (patent, partial thrombosis, or complete thrombosis) as determined during the index hospitalization. Cox proportional-hazards analysis was performed to identify independent predictors of death.

RESULTS

During the index hospitalization, 114 patients (56.7%) had a patent false lumen, 68 patients (33.8%) had partial thrombosis of the false lumen, and 19 (9.5%) had complete thrombosis of the false lumen. The mean (+/-SD) 3-year mortality rate for patients with a patent false lumen was 13.7+/-7.1%, for those with partial thrombosis was 31.6+/-12.4%, and for those with complete thrombosis was 22.6+/-22.6% (median follow-up, 2.8 years; P=0.003 by the log-rank test). Independent predictors of postdischarge mortality were partial thrombosis of the false lumen (relative risk, 2.69; 95% confidence interval [CI], 1.45 to 4.98; P=0.002), a history of aortic aneurysm (relative risk, 2.05; 95% CI, 1.07 to 3.93; P=0.03), and a history of atherosclerosis (relative risk, 1.87; 95% CI, 1.01 to 3.47; P=0.05).

CONCLUSIONS

Mortality is high after discharge from the hospital among patients with type B acute aortic dissection. Partial thrombosis of the false lumen, as compared with complete patency, is a significant independent predictor of postdischarge mortality in these patients.

Long-term survival in patients presenting with type B acute aortic dissection: insights from the International Registry of Acute Aortic Dissection

BACKGROUND

Follow-up survival studies in patients with acute type B aortic dissection have been restricted to a small number of patients in single centers. We used data from a contemporary registry of acute type B aortic dissection to better understand factors associated with adverse long-term survival.

METHODS AND RESULTS

We examined 242 consecutive patients discharged alive with acute type B aortic dissection enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. Kaplan-Meier survival curves were constructed, and Cox proportional hazards analysis was performed to identify independent predictors of follow-up mortality. Three-year survival for patients treated medically, surgically, or with endovascular therapy was 77.6+/-6.6%, 82.8+/-18.9%, and 76.2+/-25.2%, respectively (median follow-up 2.3 years, log-rank P=0.61). Independent predictors of follow-up mortality included female gender (hazard ratio [HR],1.99; 95% confidence interval [CI], 1.07 to 3.71; P=0.03), a history of prior aortic aneurysm (HR, 2.17; 95% CI, 1.03 to 4.59; P=0.04), a history of atherosclerosis (HR, 2.48; 95% CI, 1.32 to 4.66; P<0.01), in-hospital renal failure (HR, 2.55; 95% CI, 1.15 to 5.63; P=0.02), pleural effusion on chest radiograph (HR, 2.56; 95% CI, 1.18 to 5.58; P=0.02), and in-hospital hypotension/shock (HR, 12.5; 95% CI, 3.24 to 48.21; P<0.01).

CONCLUSIONS

Contemporary follow-up mortality in patients who survive to hospital discharge with acute type B aortic dissection is high, approaching 1 in every 4 patients at 3 years. Current treatment and follow-up surveillance require further study to better understand and optimize care for patients with this complex disease.

A Prospective Study of Medically Treated Acute Type B Aortic Dissection

OBJECTIVE

To study prospectively aneurysm formation, need of surgery, incidence of rupture and mortality in patients with conservatively treated acute type B aortic dissection.

METHODS

All patients referred to us with acute type B dissection between January 1990 and December 2001 were candidates for this prospective treatment and follow-up study. Patients deemed not to be in need of acute surgical repair were included after aggressive antihypertensive treatment. The follow-up protocol included close blood pressure control, clinic visits with physical examination, chest x-ray and spiral CT or MRI at 3 and 6 months and annually thereafter.

RESULTS

Sixty-six patients were followed for a mean of 79 months (range 22-179). The actuarial survival rate was 82% at 5 years and 69% at 10 years. Eighty-five percent remained free from dissection-related death at 5 years and 82% at 10 years. Ten patients (15%) developed aneurysm (>6 cm) of the dissected aorta. Three of these 10 patients died from aortic rupture and 2 underwent elective surgical repair. Of the 56 patients without aneurysm, one died from rupture and one died suddenly for causes unknown. One patient was treated with endovascular stent-graft. Five patients sustained a new type A aortic dissection which in all but one were fatal. In 26 patients the initial dissection was categorized as intramural hematoma. Twelve of these patients had, in addition to the hematoma, areas with localized dissection/ulcer-like projection. The latter was found to be a predictor of aortic event (dissection-related death, rupture, new type A aortic dissection, aneurysm formation) during follow-up, as was an initial diameter of >4.0 cm at first CT-scan during the acute event.

CONCLUSIONS

Conservatively treated acute type B dissection has a low incidence of aneurysm formation and rupture during the chronic phase. These results must be matched or improved upon before endovascular stent-grafting or early aortic surgical repair can be regarded as the primary treatment of choice.

Quality of Life in Patients with Chronic Type B Aortic Dissection

OBJECTIVE

To study functioning and well-being among patients with conservatively treated acute type B aortic dissection.

DESIGN

Cross-sectional survey.

METHODS

Patients referred with acute type B dissection between January 1990 and November 2000 were prospectively followed after conservative initial management. In October 2002, we sent the SWED-QUAL questionnaire to all patients who were alive and had not undergone surgery of the dissected aorta. Fifty-three of 55 patients responded, 39 males and 14 females. Patient scores for the 12 aspects of health-related quality of life included in the SWED-QUAL were compared to a normative Swedish population, controlled for age and gender differences.

RESULTS

There were only minor differences in functioning and well-being between patients and the normative population. Patients reported similar emotional well-being, cognitive functioning, quality of sleep, overall general health and quality of social relations as their normative counterparts. However, patients' perception of their current health, prior health, perceived resistance to illness and health concern was worse than in the normative population. Female patients also reported worse physical functioning and a lower satisfaction with their physical functioning than male patients or female counterparts in the normative population. We did not find any significant association between length of follow-up and quality of life scores.

CONCLUSIONS

In terms of functioning and well-being, patients with uncomplicated acute type B aortic dissection, who are initially managed conservatively, differ little from a normative Swedish population. Our study supports conservative management of this group of patients.

Midterm Results of Aortic Diameter Outcomes After Thoracic Stent-Graft Implantation for Aortic Dissection: A Multicenter Study

PURPOSE

To evaluate aortic diameter outcomes after stent-graft implantation for aortic dissection in the descending thoracic aorta.

METHODS

Fifty patients with type A dissection after ascending aortic surgery (n = 10), type B dissection (n = 34), or intramural hematoma (n = 6) underwent stent-graft repair in 3 centers. Thrombosis and aortic diameter were analyzed by computed tomographic angiography at different levels of the aorta before stent-graft implantation, at discharge, and at follow-up. Measurements were standardized.

RESULTS

In all, 67 stent-grafts were implanted for acute (n = 18) and chronic (n = 32) dissection. Stent-graft placement was successfully performed with high technical success (100%) despite 4 major complications (iliac thrombosis in 2 cases, aortic rupture, and a type A dissection) in 3 (6%) patients. Complete thrombosis of the thoracic false lumen was observed in 42% and 63% of cases at discharge and at follow-up (mean 15 months), respectively. At follow-up, the diameters of the entire aorta (mean 5 mm, p < 0.05) and the false lumen (mean 11 mm, p < 0.0001) decreased. Diameters of the abdominal aorta remained stable in association with persistent false lumen perfusion at this level. Aortic diameter results were better in the subgroup of patients with intramural hematoma compared to patients with Marfan syndrome. Three early deaths unrelated to the stent-graft procedure occurred; 2 patients with partial thrombosis of the false lumen died in follow-up secondary to aortic diameter growth.

CONCLUSION

Complete thrombosis of the false lumen by stent-graft coverage of the entry tear results in decreased diameter of the entire aorta. In patients with partial thrombosis of the false lumen, the aneurysm continues to enlarge.

Will Stent-Graft Repair Emerge as Treatment of Choice for Acute Type B Dissection?

Endovascular stent grafts are now accepted globally and approved by the US Food and Drug Administration as an alternative to open surgical repair for patients with descending thoracic aortic aneurysm. However, as opposed to the abdominal aorta, application of this technology to manage thoracic aortic disease is not limited to degenerative aneurysms. In fact, international registries and surveys estimate that only 60% of the thoracic cases managed currently with stent-graft placement are aneurysms. The remainder of this experience includes acute dissection, chronic dissection, traumatic aortic injury, penetrating ulcer, intramural hematoma, aortic fistula, anastomotic pseudoaneurysm, and an embolizing lesion. In this regard, it is important to keep in mind that the present devices used in these nonaneurysmal applications are not designed to address the unique anatomical and pathological features that these lesions present. Consequently, in the future, it is possible that we will see stent-graft designs that focus specifically on the challenges of some of the nonaneurysmal thoracic aortic pathologies.

Update on Thoracic Aortic Endovascular Grafting Using the Medtronic Talent Device

This article provides a brief update on the current status of the treatment of thoracic aortic pathology using the Medtronic Talent device. Preoperative evaluation and selection criterion along with study design are described for the recently completed Phase II VALOR Trial (Evaluation of the Medtronic AVE Talent Thoracic Stent Graft System for the Treatment of Thoracic Aneurysms). In addition, the results of several recent series for the treatment of degenerative aneurysm and more complex aortic pathology such as transection, rupture and acute and chronic dissection are reviewed.

Problems Encountered during and after Stent-Graft Treatment of Aortic Dissection

PURPOSE

The authors report their experiences with the problems encountered during and after stent-graft placement in patients with aortic dissections.

MATERIALS AND METHODS

Between July 1994 and December 2003, stent-graft placement was performed in 60 patients with aortic dissections, 9 patients with Stanford type A dissection and 51 patients with type B. Ten patients had acute dissection and 50 patients had chronic dissection. Each patient was followed for 12 to 107 months (mean, 33 mo). All cases were retrospectively reviewed for any problem that occurred during and after the procedure.

RESULTS

During the procedure, there were two cases (3%) of stent-graft migration, one case (2%) of stent-graft torsion, two cases (3%) of stent-graft folding due to oversizing, three cases (5%) of persistent thoracic false lumen flow by the appearance of a hidden intimal tear, one case (2%) of new intimal tear that resulted in retrograde type A dissection, and 12 cases (20%) of type I endoleaks on aortograms taken immediately after the procedure. During the follow-up period, one case (2%) of transient cerebral ischemia, six cases (10%) of persistent type I endoleaks, two cases (3%) of type II endoleaks through the intercostal artery, four cases (7%) with progressive dilatation of abdominal false lumen, six cases (10%) of new intimal tears which resulted in saccular aneurysms (n=4) or new dissections (n=2) on either or both ends of the stent-graft, and two cases (3%) of mechanical failure were observed. Overall, five patients (8%) required surgical conversion, and there were no cases of procedure-related mortality.

CONCLUSION

Various problems can occur during and after stent-graft placement in aortic dissection. The thorough evaluation of preoperative imaging and close follow-up are mandatory to optimize the management of such problems.

Endovascular stent-grafts treatment in acute aortic dissection (type B): Clinical outcomes during early, late, or chronic phases

OBJECTIVE

This is a prospective study to evaluate the clinical outcomes of endovascular repair in patients with different phases of type B aortic dissection.

BACKGROUND

Endovascular repairing with stent-grafts is an innovative technique for type B acute aortic dissection. There is no previous study regarding outcomes in different time phases.

METHODS

Sixty-two patients underwent endovascular stent-grafts. There were 23 in the early phase (<24 hr), 20 in the late phase (>or=24 hr to 2 weeks), and 19 in the chronic phase (>2 weeks).

RESULTS

The early phase group had the lowest ratio of stent-grafts to patient and the shortest stent-graft length. The chronic phase group had the largest diameter of false lumen. The technical success rate was 100%; no patient died within hospital. Three patients died within 30 days, with the same death rate in every group. Compared with acute patients, the chronic group had a higher volume of contrast, a higher creatinine post-procedure, and a higher incidence of contrast-induced nephropathy. Multiple regression analysis demonstrated that creatinine and endoleak were independent factors in predicting late death (95% CI, 3.4-26%, P < 0.01). The overall cardiovascular event-free survival was 88.9% +/- 2.1% at 30 days, 87.2% +/- 4.1% at 1 year, and 81.4% +/- 6.3% at 2 years. CT angiography identified the complete or partial thrombosis of the false lumen to be 95.7%.

CONCLUSIONS

Endovascular repairing with stent-graft is safe, feasible, and able to treat type B aortic dissection in all phases. However, chronic renal dysfunction was an independent factor which contributed to a lower survival rate of chronic phase patients.

Outcome of Medical and Surgical Treatment in Patients With Acute Type B Aortic Dissection

BACKGROUND

Optimal treatment of acute type B aortic dissection remain unclear. The aim of this study was to assess the clinical outcome of acute type B aortic dissection.

METHODS

In the last 8 years, 107 patients were admitted for acute type B aortic dissection. We medically treated patients at the time of onset with antihypertensives. Surgery was considered if there is intractable pain, uncontrolled hypertension, severe aortic branch malperfusion, or aneurysm expansion.

RESULTS

Twenty-nine patients had pleural effusion (27%), 9 patients had leg ischemia (8%), 5 patients had impending rupture, and 2 patients had aneurysm enlargement exceeding 60 mm on repeated imaging studies. A total of 16 patients (15%) underwent surgical intervention: 8 extra-anatomical bypass for leg ischemia, 1 in situ infrarenal aortoiliac bypass for distal aortic obstruction, and 7 thoracic aortic graft replacement. Of the 8 patients with extra-anatomic bypass, 3 patients died: 2 patients died of catastrophic aortic rupture 2 and 9 days after bypass, and 1 patient died of dissection progression to type A lesion 9 days after bypass. There was no in-hospital death in 92 medically treated patients. Follow-up was 92% complete. The mean follow-up duration was 36.1 months (range, 2 to 96 months). The 6-month, 1-year, and 5-year survival rates of all patients were 96.2 +/- 1.9%, 95.2% +/- 2.1%, and 95.2% +/- 2.1%.

CONCLUSIONS

Medical treatment of acute type B aortic dissection produced good outcomes. Central aortic procedures such as aortic fenestration and endovascular stenting should be the preferred methods to treat patients with acute type B aortic dissection and leg ischemia because there was high risk of central aortic complications after extra-anatomic bypass.

Long-Term Outcome and Prognostic Predictors of Medically Treated Acute Type B Aortic Dissections

BACKGROUND

The purpose of this study was to examine the long-term outcome and the prognostic predictors related to the development of complications associated with acute type B aortic dissection.

METHODS

Seventy-six medically treated patients with acute type B aortic dissection were examined between 1990 and 2001. The events associated with aortic dissection included dissection-related death, rupture, visceral ischemia, lower limb ischemia, an increase in the maximum aortic diameter greater than 50 mm, and a mean enlargement rate of greater than 5 mm per year.

RESULTS

Among the 76 patients 10 (13%) underwent chronic phase surgery and 25 (33%) presented with an event. A statistically significant difference was observed between patients with and without events with regard to atherosclerotic factors, blood flow status in the false lumen, maximum aortic diameter upon admission, mean aortic enlargement rate, and blood pressure control during follow-up. Of these factors a patent false-lumen and a maximum aortic diameter greater than 40 mm upon admission were the most strongly associated factors with regard to the development of events. Patients with a patent false-lumen and a maximum aortic diameter greater than 40 mm upon admission were determined to exhibit significantly higher event rates than other patients.

CONCLUSIONS

In determining the appropriate therapeutic approach for acute type B aortic dissection, it is important to pay careful attention to the predictors of a patent false-lumen and a maximum aortic diameter greater than 40 mm at onset to improve the long-term outcome.

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.

Acute type B aortic dissection in elderly patients: clinical features, outcomes, and simple risk stratification rule

BACKGROUND

The clinical features and outcomes of elderly patients with acute type B aortic dissection (ABAD) are less well known. Accordingly, we sought to evaluate the clinical features and outcomes and derive a simple risk stratification rule for elderly with ABAD.

METHODS

We categorized 383 patients with ABAD enrolled in the International Registry of Acute Aortic Dissection into two strata (aged less than 70 years and aged 70 years or more) and compared their clinical features and in-hospital outcomes. Further, we developed a clinical decision rule to risk-stratify elderly with ABAD.

RESULTS

Forty-two percent (161 of 383) of patients with ABAD were aged 70 years or more. Hypertension, diabetes, history of prior aortic aneurysm, and arteriosclerosis were more common in the elderly patients, whereas Marfan syndrome and cocaine abuse were less common. The in-hospital complication of hypotension/shock was more common among elderly, and malperfusion of a visceral organ less frequent among elderly patients. In-hospital mortality was higher in the elderly cohort compared with the younger patients (16% versus 10%, p = 0.07). A classification tree identified that elderly patients with hypotension/shock had the highest risk of death (56%). In absence of this, any branch vessel involvement was associated with the next highest mortality rate (28.6%) followed by presence of periaortic hematoma (10.5%). In contrast, elderly patients without any of these three risk factors had an extremely low mortality rate (1.3%).

CONCLUSIONS

Our study highlights important differences between older and younger patients with ABAD in their clinical characteristics, management, and outcomes. We also propose a simple decision rule that allows stepwise risk-stratification in elderly patients with ABAD.

Management Trends and Early Mortality Rates for Acute Type B Aortic Dissection: A 10-Year Single-Institution Experience

This study was undertaken to assess trends in management over time and to determine predictors of early mortality for acute type B aortic dissection. Fifty-three consecutive patients with acute type B aortic dissection over a 10-year period were reviewed. Baseline demographics as well as in-hospital data regarding symptoms, type of initial management, surgical indications, type of surgical intervention, and early mortality rates were collected. Independent predictors of early mortality were determined by logistic regression. Forty-one of 53 (77.4%) patients were initially managed medically with a total of 26 (49.1%) ultimately undergoing surgical repair during hospitalization. Crude early mortality was 30.8% in the surgical group vs. 14.8% in the medical group (p = 0.20). Improvements in early mortality were observed over time for surgery (58.3%, first half vs. 7.1%, second half; p = 0.019) and medical therapy (21.4%, first half vs. 7.7%, second half; p = 0.64). Early mortality was 50% in 16 patients having open aortic surgery vs. 0% in 10 patients undergoing endovascular stent graft repair (p < 0.005). Independent predictors of early mortality included only renal dysfunction (odds ratio [OR] 7.39), aortic rupture (OR 8.72), and date of admission during the study period (OR 0.712). Despite improvements over time in early mortality that appear associated with the increasing use of endovascular stent grafts, patient-specific factors are still the most important independent predictors of early mortality in acute type B aortic dissection.

Existence of abdominal aortic aneurysms in patients with thoracic aortic dissections

OBJECTIVE

The objective of this study was to determine the coexistence or later development of pararenal and infrarenal abdominal aortic aneurysms (AAAs) in patients with thoracic aortic dissections.

METHODS

One hundred forty-five patients (95 men, 50 women) encountered from 1992 to 2001 with thoracic aortic dissections-excluding those associated with trauma, those with Marfan's syndrome, and those with thoracoabdominal aortic aneurysms-were studied. The most common risk factors included hypertension (59%) and a history of tobacco use (52%). Type III dissections affected 86 patients (59%), and type I dissections affected the remaining 59 patients (41%). Aortic computed tomography (CT) scans were obtained annually. Data were assessed by univariate and multivariate analyses.

RESULTS

Five patients (3%) had a history of AAA repair prior to their thoracic aortic dissection diagnosis-3 were type III dissections and 2 were type I dissections. Twelve patient's (8%) AAAs were diagnosed with the initial CT study of their thoracic aortic dissection. Type III dissections accounted for all but one of these (11 of 12, 92%). Ten additional AAAs (7%) developed in the 128 patients with no initial evidence of an AAA being recognized from 1 to 48 months (average 16 months) after the thoracic aortic dissection was diagnosed. Type III dissections affected 8 of these 10 patients. Among the total 27 AAAs noted in this series, 74% (20 AAAs) were not continuous with the thoracic aortic dissection. In the univariate analysis, age (P =.0002), male gender (P =.044), history of smoking (P =.01), chronic obstructive pulmonary disease (P <.001), duration of dissection (P =.05), and presence of type III dissection (P =.009) were associated with the presence of an AAA. In the multivariate analysis, both chronic obstructive pulmonary disease (odds ratio 5.4, 95% CI, 1.3 to 22.3; P =.02) and age (OR 1.06, 95% CI, 1.02 to 1.11; P =.004) were significant predictors of the development of AAAs.

CONCLUSION

This study documented that patients with thoracic aortic dissections are at risk to harbor or develop a later AAA. This finding supports the tenet that abdominal CTs or ultrasound scanning should be mandatory in the follow-up of patients with known thoracic aortic dissections.