Predictors of outcome after endovascular repair for chronic type B dissection. Eur J Vasc Endovasc Surg. 2012;43:386-391. [PMID: 22326695 DOI: 10.1016/j.ejvs.2012.01.016]

Impact of secondary interventions on mortality after fenestrated branched endovascular aortic aneurysm repair

BACKGROUND

Fenestrated and branched endovascular aortic repair (F/BEVAR) is increasingly used to manage pararenal and thoracoabdominal aortic disease (TAAA). Device-related reintervention after F/BEVAR is common, but little is known about its impact on postoperative mortality. The purpose of this analysis was to describe secondary intervention (SI) after F/BEVAR and determine the impact of these procedures on patient survival.

METHODS

A single-center review was done on all consecutive F/BEVARs performed from 2010 to 2016. Primary end points were incidence of secondary aortic, branch, and/or access vessel‒related SI, and survival. SI was categorized as minor endovascular (branch restenting, access vessel treatment, or percutaneous coil embolization), major endovascular (new aortic graft placement), or open (bleeding, access vessel, and/or aortic). Kaplan-Meier methodology was used to estimate freedom from SI and survival. Multivariable analysis was used to identify predictors of SI.

RESULTS

A total of 308 F/BEVAR procedures were performed (75% physician-modified, 18% custom, 7% Zfen), with 1022 vessels revascularized (celiac, 228; superior mesenteric artery [SMA], 263; renal, 525). There were 117 (39%) extent I-III TAAA, 132 (44%) extent IV TAAA/4-vessel pararenal, and 54 (18%) <4-vessel pararenal repairs performed. Any type of SI occurred in 24% (74) of patients during the mean follow-up of 20 ± 21 months. The majority of reinterventions were endovascular (minor, 53% [n = 39]; major, 32% [n = 24]), whereas 12% (n = 9) were open and 3% (n = 2) hybrid. Primary indication for SI included: 22 (29%) with branch-related endoleaks (1C or III); 15 (22%) with proximal or distal aortic degeneration; 8 (12%) with branch vessel thrombosis/stenosis; 10 (11%) with aortic device type III endoleak/loss of overlap; 4 (6%) with postoperative mesenteric or renal bleeding events; 5 (5%) with type II endoleak; 3 (5%) with access vessel complication; and 2 (3%) with graft infection. Most SIs were elective (65%; n = 48) with the remainder occurring emergently (24%; n = 18) or for symptoms/urgently (11%; n = 8). Compared with endovascular remediation, open SI was more likely to be emergent (89%, 8 of 9; P = .001). Freedom from SI was 80 ± 3% and 64 ± 4% at 1 and 3 years, respectively. One- and 5-year survival with or without SI was: 1 year, 88 ± 4% vs 81 ± 3%; 5 years, 76 ± 5% vs 59 ± 4% (log rank test, P = .06). There was no survival difference based on type of SI (log rank test, P = .3). Extent I-III TAAA (HR, 1.6; 95% CI, 0.98-3.3; P = .06) and history of cerebrovascular disease (HR, 1.8; 95% CI, 0.97-2.6; P = .07) were predictive of SI.

CONCLUSIONS

SIs after F/BEVAR most frequently involve branch vessel or aortic device remediation procedures; however, they do not negatively impact out-of-hospital survival. These results further highlight the crucial role of imaging surveillance after F/BEVAR to maintain durability. Discussions with patients, periprocedural planning, and the next generation of device design must focus on issues surrounding the risk of device-related SI events.

High intimal flap mobility assessed by intravascular ultrasound is associated with better short-term results after TEVAR in chronic aortic dissection

Thoracic endovascular aortic repair (TEVAR) in chronic aortic dissection remains controversial. We analysed whether a high intimal flap mobility (IFM) of the dissection membrane has an impact on aortic remodelling after TEVAR in chronic Type B aortic dissection. Patients undergoing TEVAR with intravascular ultrasound (IVUS) were analysed and IFM was calculated. High IFM was defined as maximum flap amplitude >3 mm. For determining aortic remodelling, the degree of true lumen (TL) expansion was analysed in the last available follow-up CT. Fifty-two patients (63.6 ± 15.4 years) with a mean follow-up of 26.6 ± 20.7 months were analysed. The mobile flap group (n = 29) showed higher absolute TL expansion at the distal stent-graft (5.9 ± 3.1 vs. 3.3 ± 5.4 mm; p = 0.036) and a higher increase in TL diameter (18 ± 10 vs. 9 ± 15%; p = 0.017) compared to the non-mobile group (n = 23). Basic TEVAR-related outcome characteristics were comparable, but the mobile intimal flap group showed a lower re-intervention rate (3 vs. 8pts.; p = 0.032) in chronic dissections. High IFM in chronic Type B aortic dissection is linked to improved aortic remodelling and is associated with a lower re-intervention rate over time. IVUS assessment of IFM in chronic Type B aortic dissection might be helpful in identifying patients with better remodelling after TEVAR.

False lumen embolization in chronic aortic dissection promotes thoracic aortic remodeling at midterm follow-up

OBJECTIVE

Failure of thoracic endovascular aortic repair (TEVAR) in chronic aortic dissections can be partially explained by retrograde false lumen (FL) flow through distal re-entry tears. After implantation of a thoracic stent graft, FL thrombosis occurs in less than 50% of the cases. The objectives of this study were to describe the feasibility and outcomes of FL embolization in patients with chronic aortic dissections.

METHODS

Between June 2015 and January 2018, 27 patients (mean age, 61 ± 14 years) with chronic aortic dissection underwent FL embolization as an adjunct during or after TEVAR placement procedure. Indications for embolization were (1) symptomatic chronic aortic dissections with pain or rapid growth of aortic diameter (≥5 mm/y) requiring rapid exclusion of the aneurysm, (2) aneurysmal dilatation with persistent FL retrograde flow after TEVAR, and (3) large FL aneurysms (≥55 mm) that might lead to persistent retrograde flow. Twenty patients presented with type B chronic aortic dissections (74.1%) and seven presented a residual type A chronic aortic dissections (25.9%). Eight patients had a previous aortic arch replacement (29.6%). Six patients had previous repair with TEVAR (22.2%). The delay between the onset of dissection and the first endovascular repair was 47 months (range, 3-144). Spinal fluid drainage was used in 74.1% of cases (20/27 patients). Embolization devices included coils and vascular plugs.

RESULTS

The technical success rate was 100% (27/27). Complete spinal cord ischemia was observed in one patient (3.7%). There was one hospital death from pneumonia after zone 1 supra-aortic trunk debranching with TEVAR and embolization. After the index procedure, FL thrombosis was observed in 81.5% of patients (22/27) on late phase computed tomography angiography. Five patients required two or more embolization procedures, leading to a high rate of complete FL thrombosis (92.6%). One patient presented a type IB endoleak and one patient presented a type II endoleak. Radiologic follow-up was 20 ± 10 months. The maximum thoracic aortic diameter significantly decreased from 63 mm to 54 ± 10 mm (P < .001).

CONCLUSIONS

Embolization of the FL of chronic aortic dissections is technically feasible with a low morbidity rate. The FL thrombosis is observed in the majority of case and promotes favorable thoracic aortic remodeling. Longer follow-up is needed to confirm these good results on the thoracic aorta and this technique may, therefore, improve the results of TEVAR in chronic aortic dissections.

Modified Candy-Plug Technique for Rescue Type B Aortic Dissection with False Lumen Rupture

Despite recent advances in surgical techniques and endovascular devices, the management of ruptured type B aortic dissection remains challenging. Herein, we describe a patient with a history of chronic type B aortic dissection who presented to the emergency department with a massive left hemothorax and profound shock. Computed tomography demonstrated a thoracic dissecting aneurysm with false lumen rupture. He underwent emergent thoracic endovascular aortic repair and carotid-carotid crossover bypass in a hybrid operating room. Although the thoracic endovascular aortic repair resulted in suitable sealing over the primary entry tear, aortography revealed prominent retrograde flow through the distal re-entry tear into the false lumen. To depressurize the ruptured aortic segment fully, we implanted a modified candy-plug device in the false lumen and successfully occluded the retrograde flow. This case report illustrates the preliminary experience of using modified candy-plug device to rescue a critical patient with ruptured type B aortic dissection.

Techniques and outcomes of false lumen embolization in chronic type B aortic dissection

Endovascular strategies have been increasingly used for the treatment of chronic type B aortic dissection (cTBAD) offering better outcomes in terms of mortality and morbidity compared to open surgical repair. Aortic remodeling after standard TEVAR is less likely in cTBAD due to rigidity of the dissection membrane. Another limitation of endovascular therapy is continued retrograde false lumen perfusion with back-flow from distal entry tears. Treatment strategies in cTBAD should aim at false lumen thrombosis. There are many approaches to achieve this goal of false lumen thrombosis, but concepts as open surgery or fenestrated and branched endovascular repair are limited by either high technical and logistic demands to the surgeon or high rates of mortality and morbidity. False lumen embolization techniques offer less invasive treatment strategies with promising early results. The main strategies for false lumen embolization include the "cork in the bottle neck" technique, the Candy-Plug technique or the Knickerbocker-technique. This article describes technical aspects and early results of these new endovascular techniques of false lumen embolization in chronic aortic dissection.

Techniques and outcomes of secondary endovascular repair for postdissection TAA/TAAA

Postdissection aortic aneurysms (PDAA) affect 20-40% of patients with aortic dissection. Open repair remains the first line therapy of PDAA, but is still associated with high mortality and morbidity rates. Endovascular repair is increasingly being used as a less invasive treatment option. Thoracic endovascular aneurysm repair (TEVAR) covering only the proximal entry tear has proven to be insufficient in most patients with chronic PDAA and has a limited role only for PDAA with distal sealing zone in the thoracic aorta. In PDAA extending to the thoracoabdominal aorta, a more complex repair is needed to achieve aneurysm exclusion. Fenestrated and branched stent-grafts have been used lately in some expert centres to treat PDAA of the thoracoabdominal aorta with good preliminary results despite the technical difficulties in these patients (narrow true lumen, stiff chronic dissection flap, target vessels that originate from the false lumen [FL]). A subset of patients with aneurysmal degeneration mainly in the descending thoracic aorta, can be treated with TEVAR landing proximal to the celiac artery along with adjuvant techniques such as coils, plugs, glue or "Candy-Plug" and "Knickerbocker" concepts to occlude the FL, preventing retrograde flow and reducing the pressure in the aneurysm. Other options that have been used in limited numbers of patients with PDAA include the PETTICOAT (provisional extension to induce complete attachment) and STABILISE (Stent-Assisted Balloon-Induced Intimal Disruption and Relamination in Aortic Dissection Repair) techniques. This article aims to review the outcomes of different endovascular techniques and strategies available for the repair of PDAA.

Aortic remodelling after thoracic endovascular aortic repair for acute and subacute type B aortic dissection

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) in the current era has gained widespread acceptance as the modality of choice for the treatment of complicated aortic dissection (AD). However, reports on clinical results of TEVAR treatment of AD patients are mainly comparisons and analyses of results between patients in the acute and chronic phases, few reports have described the postoperative aortic remodelling of patients with subacute AD after TEVAR. The aim of this study was to investigate aortic remodelling after TEVAR in acute and subacute Stanford type B AD patients.

METHODS

The clinical data of 38 Stanford type B AD patients who received TEVAR treatment in our hospital between July 2012 and December 2017 were retrospectively analysed. The maximum diameters of the aorta, the mean diameters of the true lumens (TLs) and the false lumens (FLs) of the aorta in the dissection range before and after TEVAR treatment were measured. All diameters between different groups or in the same group before and after therapy were compared using nonparametric tests. Count data were examined using the χ² test.

RESULTS

The 38 patients were 31.0-82.0 years old with a mean age of 57.0±11.0 years, including 31 men and 7 women, with 22 patients in the acute phase and 16 patients in the subacute phase. Among the 38 patients included in this study, 7 (18.4%) patients had endoleaks after treatment. No perioperative deaths occurred. Analyses of computed tomography angiography measurement results showed that the baseline maximum diameters of the aorta, TLs and FLs before TEVAR between the acute and subacute groups were not significantly different (P=0.193, P=0.301 and P=0.067, respectively). After TEVAR treatment, the maximum diameters of the aorta and the diameters of the FLs were different between the two groups (P=0.005 and P=0.012), but the diameters of the TLs were not (P=0.069). The diameters of the TLs increased, and those of FLs decreased significantly in the acute and subacute groups after TEVAR (P<0.001, P<0.001, P<0.001 and P=0.007, respectively); the maximum diameters of the aorta decreased significantly in the acute group (P<0.001), but they did not change obviously in the subacute group (P=0.121).

CONCLUSIONS

TEVAR offers satisfactory results for the treatment of type B AD. Acute AD may be associated with better aortic remodelling compared to subacute AD after TEVAR.

Type B aortic dissection: new perspectives

Background

Stanford type B aortic dissection is one of the aortic catastrophes with a high mortality and morbidity that needs immediate or delayed treatment, either surgically or endovascularly. This comprehensive review article addresses the current status of open, endovascular and hybrid treatment options for type B aortic dissections with the focus on new therapeutic perspectives.

Methods

Evaluation of currently available evidence based on randomized and registry data and personal experience.

Results

All type B dissections require prompt medical treatment to prevent aortic rupture. Acute complicated dissections are nowadays treated by endografting to reroute blood flow into the true lumen and promote false lumen thrombosis and future aortic remodeling. In acute uncomplicated situations the position of endografting is less clear and should be further delineated; however, on the long run also in these situations endografting might be protective for future aortic catastrophes in certain patient categories. In the chronic dissection with aneurysm formation of the descending thoracic and/or thoracoabdominal aorta, especially in connective tissue disorders, open surgery offers nowadays the best immediate results with long durability. Thoracic endografting plays only a minor role in these circumstances but branched and fenestrated endografting are very promising techniques. Hybrid techniques can offer the solution for high risk patients that are not suitable for open surgery.

Conclusions

Emergent thoracic endografting is the golden standard for all complicated type B dissections while uncomplicated patients with high-risk features might benefit from endovascular repair. Open surgery is limited for chronic post dissection aneurysms. Aortic surveillance is of paramount importance in all situations.

Conservative management versus endovascular or open surgery in the spectrum of type B aortic dissection

Background

Type B aortic dissection is a life-threatening acute aortic condition often with acute ischemic signs or symptoms. With initial management focusing on alleviating malperfusion and pain, and avoiding propagation of dissection or rupture both systolic blood and pulse pressure should be reduced initially by an aggressive medical approach. In the setting of persistent signs of complications endovascular strategies have replaced open surgery and led to a fourfold increase in early survival and better long-term outcomes.

Methods

An electronic health database search was performed on articles published between January 2006 and July 2017. Publications were included in this review if (I) the index aortic pathology was type B aortic (distal) dissection; (II) when medical management, open surgical replacement or thoracic endovascular aortic repair were among those options; (III) when at least one of all basic outcome criteria such as survival, spinal cord ischemia and cerebrovascular accident was reported; (IV) when ≥15 serial patients were included. A total of 62 studies were eligible and analysed.

Results

Our manuscript has summarized data collected over 12 years on management specific outcomes in the setting of distal aortic dissection and provides an up-to-date interpretation of the published evidence. For complicated cases, treated acutely, the 30-day or in-hospital mortality was 7.3% when managed by endovascular means, whereas the pooled rate for 30-day or in-hospital mortality was 19.0% when subjected to open repair. For acute uncomplicated type B dissection usually treated with blood pressure lowering medications, the pooled 30-day or in-hospital mortality rate was 2.4%. Survival rates at 5 years averaged at 60% (40% mortality). Freedom from any aortic event ranged from 34.0% to 83.9%, underlining an inherent risk of progression and late complications. For chronic complicated type B dissection, the rates of stroke, paraplegia and operative mortality following endovascular repair ranged from 5% to 13%, 2% to 13% and 2 to 13%, respectively, while 5-year survival rates after open repair ranged from 60% to 90%. In chronic uncomplicated type B dissection almost 90% of patients survive initial hospitalization and were subjected to medical management with a 5-year survival of 50-80%. However, up to 20-55% of medically treated patients develop aneurysmal degeneration after 5 years with an unknown risk of rupture.

Conclusions

Currently, the less invasive strategy of endovascular repair (as compared to open surgery) provides improved 30-day or in-hospital survival in the setting of complicated acute type B aortic dissection and may seek broad application. Open surgical aortic reconstruction should be left to experienced aortic centres if endovascular management is not an option.

Modified 'candy-plug' technique for chronic type B aortic dissection with aneurysmal dilatation: a case report

Background

The original ‘candy-plug’ technique has been reported to be beneficial for the treatment of residual perfused false lumen in patients with aortic dissection. However, this technique is also associated with several problems, such as narrowing of the true lumen and damage to the flap or vessel wall. Therefore, we modified the procedure to overcome these problems. Here we report a case in which the patient was successfully treated using the modified procedure.

Case presentation

A 59-year-old man presented with chronic type B aortic dissection with aneurysmal dilatation. The patient had undergone prosthetic graft replacement of the ascending aorta for acute type A aortic dissection 3 years previously and replacement of the descending aorta for residual type B aortic dissection with aneurysmal dilatation 1 year previously. After these procedures, the residual false lumen aneurysm of the distal descending aorta expanded to 57-mm in diameter. Endovascular stent grafting was successfully performed using the modified ‘candy-plug’ technique with relining of the true lumen and occlusion of the false lumen. The patient was discharged 10 days after the procedure. Follow-up imaging at 1 year showed a completely thrombosed false lumen aneurysm.

Conclusion

The modified ‘candy-plug’ technique is useful for treatment of residual type B aortic dissection with aneurysmal dilatation.

Type B Aortic Dissections: Current Guidelines for Treatment

Stanford type B aortic dissections (TBADs) involve the descending aorta and can present with complications, including malperfusion syndrome or aortic rupture, which are associated with significant morbidity and mortality if left untreated. Clinical diagnosis is straightforward, typically confirmed using CT angiography. Treatment begins with immediate anti-impulse medical therapy. Acute TBAD with complications should be repaired with emergent thoracic endovascular aortic repair (TEVAR). Uncomplicated TBAD with high-risk features should undergo TEVAR in the subacute phase. Open surgical repair is seldom required and reserved only for select cases. It is critical to follow these patients clinically and radiographically in the outpatient setting.

The Candy-Plug Technique: Technical Aspects and Early Results of a New Endovascular Method for False Lumen Occlusion in Chronic Aortic Dissection

PURPOSE

To describe the technical aspects and early results of the Candy-Plug technique for endovascular false lumen occlusion in chronic aortic dissection.

METHODS

A retrospective single-center study analyzing 18 consecutive patients (mean age 63 years, range 44-76; 16 men) with thoracic false lumen aneurysm in chronic aortic dissection. All patients underwent thoracic endovascular aortic repair with false lumen occlusion using the Candy-Plug technique. Primary endpoints consisted of technical success (successful deployment) and clinical success (no false lumen backflow). Secondary endpoints included 30-day mortality and morbidity as well as aortic remodeling during follow-up.

RESULTS

Technical success was 100%. Additional intraprocedural false lumen embolization at the Candy-Plug level was needed in 1 patient due to persisting false lumen backflow on the final angiogram (clinical success 94%). There were no intraprocedural complications. In the perioperative period, there were 3 minor complications: transient mild spinal cord ischemia, cervical hematoma after carotid-subclavian bypass, and a common femoral artery pseudoaneurysm. No deaths or reinterventions occurred. Complete distal false lumen occlusion was present on postoperative computed tomography in 15 patients, while 3 had minor contrast enhancement in the distal false lumen. Over a mean 9-month follow-up (range 0-26), 1 patient died due to rupture. Follow-up >6 months was available in 10 patients (mean 14.7 months, range 7-26): 7 patients showed aortic remodeling, while aneurysm size was stable in 3 patients.

CONCLUSION

The Candy-Plug technique is a feasible endovascular method to achieve false lumen occlusion and aortic remodeling in chronic aortic dissection. It is associated with low morbidity and mortality due to its minimal invasiveness.

Update in the management of type B aortic dissection

Stanford type B aortic dissection (TBAD) is a life-threatening aortic disease. The initial management goal is to prevent aortic rupture, propagation of the dissection, and symptoms by reducing the heart rate and blood pressure. Uncomplicated TBAD patients require prompt medical management to prevent aortic dilatation or rupture during subsequent follow-up. Complicated TBAD patients require immediate invasive management to prevent death or injury caused by rupture or malperfusion. Recent developments in diagnosis and management have reduced mortality related to TBAD considerably. In particular, the introduction of thoracic stent-grafts has shifted the management from surgical to endovascular repair, contributing to a fourfold increase in early survival in complicated TBAD. Furthermore, endovascular repair is now considered in some uncomplicated TBAD patients in addition to optimal medical therapy. For more challenging aortic dissection patients with involvement of the aortic arch, hybrid approaches, combining open and endovascular repair, have had promising results. Regardless of the chosen management strategy, strict antihypertensive control should be administered to all TBAD patients in addition to close imaging surveillance. Future developments in stent-graft design, medical therapy, surgical and hybrid techniques, imaging, and genetic screening may improve the outcomes of TBAD patients even further. We present a comprehensive review of the recommended management strategy based on current evidence in the literature.

Biomechanical Changes After Thoracic Endovascular Aortic Repair in Type B Dissection

Thoracic endovascular aortic repair (TEVAR) has evolved into an established treatment option for type B aortic dissection (TBAD) since it was first introduced 2 decades ago. Morbidity and mortality have decreased due to the minimally invasive character of TEVAR, with adequate stabilization of the dissection, restoration of true lumen perfusion, and subsequent positive aortic remodeling. However, several studies have reported severe setbacks of this technique. Indeed, little is known about the biomechanical behavior of implanted thoracic stent-grafts and the impact on the vascular system. This study sought to systematically review the performance and behavior of implanted thoracic stent-grafts and related biomechanical aortic changes in TBAD patients in order to update current knowledge and future perspectives.

Current management of acute type B aortic dissection

Acute type B aortic dissection (TBAD) occurs as a result of an intimal tear within the proximal thoracic aorta. Patients are typically managed acutely with aggressive antihypertensive therapy. Surgical repair is reserved for those who develop complications such as rupture or malperfusion. The surgical management of acute TBAD has changed considerably in the last decade secondary to the advent of thoracic stent grafting. Thoracic endovascular aortic repair (TEVAR) has improved early mortality and morbidity rates for patients presenting with complicated TBAD. The role of TEVAR in patients presenting with acute and subacute uncomplicated TBAD is less clear. TEVAR has been associated with increased late survival and better aortic remodeling, with low perioperative morbidity in selected patients. Recent literature suggests certain radiographic criteria may be used to predict patients developing late aortic events who would benefit from early TEVAR. The purpose of this article is to review the contemporary management of acute TBAD, discuss controversies in management and evaluate the latest research findings.

Successful surgical treatment for thoracoabdominal aortic aneurysm with leriche syndrome

Thoracoabdominal aortic aneurysm accompanied by Leriche syndrome is an extremely rare combination of aortic diseases, the surgical management of which has not been described to date. We report the successful treatment of one such case through open surgical repair of the thoracoabdominal aorta.

Thoracic endovascular aortic repair for chronic DeBakey IIIb aortic dissection

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) for chronic DeBakey IIIb dissection with associated descending aneurysm remains controversial. This study examines long-term results of TEVAR for this disorder including examination of anatomic features associated with TEVAR outcomes.

METHODS

Between July 2005 and January 2013, 32 patients underwent TEVAR for chronic (>30 days) DeBakey IIIb dissection involving the descending thoracic aorta at a single institution and constituted the study cohort.

RESULTS

The mean interval from dissection to TEVAR was 32 ± 44 months (range, 1 to 146 months). There were no 30-day or in-hospital deaths, strokes, or paraplegia. During a 54-month median follow-up, there were no aortic-related deaths. Significant thoracic aneurysm sac regression (>1 cm) in the intervened segment was observed in 89%. Thoracic remodeling was not correlated with the number of visceral vessels arising from the true lumen or the number or size of residual distal fenestrations; failure of thoracic remodeling was associated with fenestrations distal to the endograft(s) in the descending thoracic aorta, most often stent graft-induced new entry tears. Complete resolution of the thoracic and abdominal false lumen after TEVAR was observed in 15.6% (n = 5). All patients in this group had all visceral vessels arising from the true lumen and fewer than three residual distal fenestrations.

CONCLUSIONS

Thoracic endovascular aortic repair is effective for chronic DeBakey IIIb dissection with associated descending aneurysm, with excellent 30-day and long-term outcomes and significant aortic remodeling in the vast majority of patients. Thoracic remodeling does not appear dependent on distal anatomic characteristics of the true and false lumens, although care should be taken to cover all thoracic fenestrations and avoid creation of stent graft-induced new entry tears to ensure clinical success. Complete aortic remodeling was observed only in the setting of all visceral vessels off the true lumen with fewer than three residual distal fenestrations, and this would appear the ideal anatomy for TEVAR in this scenario.

Open repair of chronic complicated type B aortic dissection using the open distal technique

AIM

The present study aimed to analyze early and late outcomes after open repair of chronic type B aortic dissection.

METHODS

We retrospectively reviewed our cases of open descending thoracic aortic aneurysm (DTAA) with chronic dissection from 1991-2013. Long-term survival and aortic reinterventions were analyzed and patient comorbidities were evaluated in order to determine the risk of adverse outcomes. Furthermore, the technique for "distal first approach" is described.

RESULTS

Between 1991 and 2013, 240 (40%) descending thoracic aortic repairs with associated chronic dissection were performed. Mean age is 59 years and 178 (74%) are men. The majority of patients (218, 91%) underwent repair using the adjunct of distal aortic perfusion with cerebral spinal fluid drainage. Early mortality was 8.3% (20/240). Permanent neurologic deficit occurred in 1.3% (3/240). Stroke occurred in 2.9% (7/240), and dialysis on discharge in 6% (12/240). 5-, 10-, 15-, and 20-year survival was 72%, 60%, 45%, and 39%, respectively. Freedom from reoperation on the operated segment was 97%, 94%, 94% and 94% at 5, 10, 15 and 20 years.

CONCLUSIONS

Open repairs of chronic descending thoracic dissections can be performed with respectable morbidity and mortality. Risk of neurologic deficit remains low with use of adjuncts, and risk of reintervention on the involved aortic segment is also low. These results allow comparison with endovascular repair for chronic aortic dissection.

Current management and outcome of chronic type B aortic dissection: results with open and endovascular repair since the advent of thoracic endografting

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) has become the preferred treatment for chronic type B aortic dissection (CTBAD) at our institution. However, it remains incapable of treating all patients with CTBAD. The present study aims to review our contemporary results with open and endovascular CTBAD repairs since the advent of thoracic endografting.

METHODS

The records of all patients undergoing index repair of CTBAD (chronic DeBakey type IIIA, IIIB and repaired type I) at our institution between June 2005 and December 2013, were retrospectively reviewed.

RESULTS

A total of 107 patients underwent CTBAD repair, of whom 70% (n=75) underwent endovascular-based procedures [44 TEVAR, 27 hybrid arch and four hybrid thoracoabdominal aortic aneurysm (TAAA) repair] and 30% (n=32) underwent open procedures (nine open descending and 23 open TAAA). Connective tissue disease (CTD), prior aortic surgery and DeBakey dissection type were strongly associated with the choice of operation. The rates of stroke, paraplegia and operative mortality following endovascular-based repairs were 0%, 0% and 4% (n=3), respectively. Adverse neurologic events were higher following open repair, and rates of stroke, paraplegia, and operative mortality were 16% (n=5), 9% (n=3), and 6% (n=2), respectively. However, 1- and 5-year survival rates were similar for endovascular-based repairs (86% and 65%, respectively), and open repairs (88% and 79%, respectively). Over a median follow-up interval of 34 months, the rate of descending aortic reintervention was 24% (n=18) following endovascular-based repairs and 0% following open repairs (P=0.001). Forty-four percent (n=8) of descending aortic reinterventions were required to treat stent graft complications (five endoleak, two stent graft collapse and one stent graft-induced new entry tear) and the remainder were required to treat metachronous pathology (n=2) or progressive aneurysmal disease related to persistent distal fenestrations (n=8).

CONCLUSIONS

Endovascular repair of CTBAD was associated with excellent procedural and survival outcomes, but at the expense of further reinterventions. Open repair remains relevant for patients who are not candidates for endovascular repair and was associated with higher procedural morbidity but similar overall survival and fewer reinterventions.

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.

Mid-term outcomes and aortic remodelling after thoracic endovascular repair for acute, subacute, and chronic aortic dissection: the VIRTUE Registry

OBJECTIVE

The VIRTUE Registry describes the mid-term clinical and morphological results of thoracic endovascular repair (TEVR) in patients with type B aortic dissection.

METHODS

This was a prospective cohort study. The VIRTUE Registry is a prospective, multicentre clinical trial that enrolled patients with complicated acute (<15 days), subacute (15-92 days), and chronic (>92 days) type B aortic dissections treated with the Valiant endograft. One hundred patients were enrolled and the clinical outcomes described at the 3-year follow-up. Analysis of the aortic area and false lumen thrombosis rates defined the morphological response to TEVR in the three clinical groups.

RESULTS

Three-year all-cause mortality (18%, 4%, and 24%), dissection related mortality (12%, 4%, and 9%), aortic rupture (2%, 0%, and 4%), retrograde type A dissection (5%, 0%, and 0%), and aortic reintervention rates (20%, 22%, and 39%) were, respectively, defined for patients with acute (n = 50), subacute (n = 24), and chronic (n = 26) dissections. Analysis of aortic morphology observed that patients with subacute dissection demonstrated a similar degree of aortic remodelling to patients with acute dissection. Patients with acute and subacute dissection exhibited greater aortic plasticity than patients with chronic dissection.

CONCLUSIONS

The principle clinical findings suggest that TEVR is able to provide good protection from aortic-related death in the mid-term, but with a high rate of aortic reintervention. Analysis of aortic morphology suggested that aortic remodelling in subacute patients is similar to the acute group. Retention of aortic plasticity in the subacute group lengthens the therapeutic window for the treatment of uncomplicated type B dissection.

A systematic review of aortic remodeling after endovascular repair of type B aortic dissection: methods and outcomes

BACKGROUND

Endovascular treatments of Stanford type B aortic dissection may help to promote aortic remodeling and reduce the incidence of aortic-related complications. The aim of this study was to review published literature describing aortic remodeling after endovascular treatment of aortic dissection.

METHODS

A systematic review of the literature was performed which was compliant with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The type of aortic morphology measurements made and the methods used to make them were characterized. The endpoints of interest were the change in these measurements over time.

RESULTS

After initial screening, 77 articles were identified; 16 of which met the inclusion criteria. Few studies used three-dimensional reconstruction software and none had validated their measurement protocol. True lumen (TL) and false lumen (FL) diameters, areas, and in some cases volumes were measured. Studies assessed the aorta at a variety of different levels and over different periods of follow-up. Acute dissection patients displayed more consistent degree of remodeling (thoracic FL thrombosis in 80% to 90%) than chronic dissection patients (38% to 91%). Less remodeling was seen below the diaphragm in both groups.

CONCLUSIONS

Aortic remodeling after treatment for dissection is described in a highly heterogeneous manner. Despite this there appears to be a greater degree of complete FL resolution in patients with acute dissection than chronic. Factors such as length of aortic coverage and timing of treatment may explain the variation seen in the chronic dissection group. Consensus-based reporting standards are required to synthesize evidence and inform clinical decisions regarding patient selection and operative timing.

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.