Endovascular Repair of Acute Type B Aortic Dissection: Long-Term Follow-Up of True and False Lumen Diameter Changes

Comparison of long-term clinical outcome between patients with chronic versus acute type B aortic dissection treated by implantation of a stent graft: a single-center report

BACKGROUND

Stent grafting for treatment of type B aortic dissection has been extensively used. However, the difference in the long-term clinical outcome between patients with chronic versus acute type B aortic dissection remains unknown. This study aimed to analyze the difference in long-term clinical outcome after endovascular repair for patients with chronic (≥2 weeks) versus acute (<2 weeks) type B aortic dissection.

METHODS

Between May 2000 and June 2011, a total of 174 patients with type B aortic dissection (56 chronic, 118 acute) treated by endovascular repair were studied prospectively. Follow-up three-dimensional computed tomography scanning and aortoangiography were scheduled at 3-6 months after the index procedure. Propensity score matching was used to compare the difference in the endpoint between the two groups.

RESULTS

The procedure-related event rate was 18.6% in the acute group and 5.4% in the chronic group (P = 0.021), but this difference became nonsignificant after propensity score matching. At the end of follow-up (mean 2.49 years), overall and aorta-related mortality was 11.0% and 7.6%, respectively, in the acute group, and was not significantly different from that in the chronic group (3.6% and 3.6%, P = 0.148 and P = 0.506, respectively). Both false and true lumina showed significant remodeling over time, with >93% complete false-lumen thrombosis. Untreated tear and type I endoleak were predictors of clinical events during follow-up.

CONCLUSION

Comparable long-term clinical results were achieved in patients with chronic or acute type B aortic dissection after implantation of a stent graft.

Early malperfusion, ischemia reperfusion injury, and respiratory failure in acute complicated type B aortic dissection after thoracic endovascular repair

BACKGROUND

The aim of this study was to determine the early mortality and major complications of acute complicated type B aortic dissection (ACBD) after thoracic endovascular aortic repair (TEVAR).

METHODS

Twenty-six consecutive patients with ACBD who underwent TEVAR were included. Clinical indications before TEVAR and in-hospital mortality and major complications after TEVAR were analyzed and compared with similar reports.

RESULTS

TEVAR was technically successful in all cases. In-hospital mortality occurred in four patients (15%), and major complications occurred in an additional four patients (15%). Three of the four (75%) of the deaths were associated with malperfusion and ischemia reperfusion injury (IRI), and 3/4 (75%) of the major complications were caused by respiratory failure (RF).

CONCLUSIONS

In-hospital mortality associated strongly with severe end-organ malperfusion and IRI, while major complications associated with RF, during TEVAR. Our results indicate that malperfusion, IRI and respiratory failure during TEVAR should be carefully monitored and aggressively treated.

What makes the difference between the natural course of a remaining type B dissection after type A repair and a primary type B aortic dissection?

OBJECTIVES

To analyse the outcome and need for intervention [surgery or thoracic endovascular aortic repair (TEVAR)] in patients after surgery for remaining type B dissection after type A repair and primary type B aortic dissection.

METHODS

Within a 10-year period, 247 patients with remaining type B after type A, and 112 patients with primary type B aortic dissection were analysed. We assessed the clinical outcome as well as the need for intervention (surgery or TEVAR) within the aortic arch and the thoracoabdominal aorta as well as risk factors.

RESULTS

The median follow-up was 23 months (interquartile range 5-52). There was a significant difference with regard to the status of the primary entry tear between patients after surgical repair of an acute type A aortic dissection and primary acute type B aortic dissection (patent vs. non-patent entry 35 vs. 83%, P < 0.001). The overall need for any kind of intervention (surgery or TEVAR) was 19%. Multivariate Cox regression analysis revealed a patent primary entry tear in patients after surgery for acute type A aortic dissection as an independent predictor for intervention (surgery or TEVAR) during follow-up [odds ratio (OR) 6.4; confidence interval (CI) 1.39-29.81, P = 0.017]. Multivariate Cox regression analysis did not reveal a patent primary entry tear in patients after acute type B aortic dissection as an independent predictor for intervention (surgery or TEVAR) during follow-up (OR 0.67; CI 0.27-1.69, P = 0.671). Finally, the thrombosis status of the false lumen was not an independent predictor for intervention (surgery or TEVAR) either in patients after surgery for acute type A aortic dissection (OR 3.46; CI 0.79-15.16, P = 0.100) or in patients after acute type B aortic dissection (OR 0.77; CI 0.31-1.93, P = 0.580).

CONCLUSIONS

A remaining type B dissection after type A repair and a primary type B aortic dissection represent two distinct pathophysiological entities with regard to late outcome. The need for any kind of intervention in the thoracoabdominal aorta is significantly higher in primary type B aortic dissections. A remaining patent primary entry tear independently predicts the need for intervention (surgery or TEVAR) in patients after surgery for acute type A aortic dissection and, thereby, remains the main target of initial therapy. The thrombosis status of the false lumen seems to be of secondary importance.

Complicated acute type B thoracic aortic dissections: endovascular treatment for visceral malperfusion and pseudoaneurysms

PURPOSE

Morbidity and mortality of acute type B thoracic aortic dissections remain alarmingly high. Endoluminal options are promising.

METHODS

A single-center 5-year review of 17 acute type B aortic dissections complicated by visceral malperfusion (11) or pseudoaneurysm formation (6) treated with endovascular intervention. Interventional techniques included endografting (15) and/or percutaneous fenestration (4). Median follow-up is 28 months (range 0-76 months).

RESULTS

Median age was 55 years; 30-day death, stroke, and paraplegia rates were 0%, 17.6%, and 5.9%. Success reversing visceral ischemia or sealing a pseudoaneurysm was 100%. Cross-sectional imaging demonstrated that the false lumen was thrombosed in 9 patients, partially thrombosed in 6 patients. Late events include 1 delayed proximal type I endoleak, 1 delayed rupture of the thoracic aorta requiring successful emergent open surgical repair, and 2 unrelated late deaths.

CONCLUSION

Endovascular approaches to type B dissections presenting with visceral malperfusion and/or pseudoaneurysm can achieve acceptable early results.

Hybrid procedures combining conventional and thoracic endovascular aortic repair for thoracic aortic aneurysms

PURPOSE

To minimize surgical invasiveness for extensive aortic aneurysms and expand the indications for thoracic endovascular aortic repair (TEVAR), we evaluated outcomes of hybrid procedures combining conventional surgical aortic repair and TEVAR for thoracic aortic aneurysms.

METHODS

The following hybrid procedures were performed: second-stage TEVAR after total aortic arch replacement using the elephant trunk as the landing zone in 17 patients; and for multiple aortic aneurysms, vascular graft replacement and TEVAR in 13 patients, vascular graft replacement and TEVAR with bypass in 2 patients, and TEVAR with bypass in 23 patients.

RESULTS

There were three (5.3%) hospital deaths, from serious complications including stroke, paraplegia, paraparesis, and aspiration pneumonia; and eight late deaths. There was only one aneurysm-related death, of a patient who underwent emergency surgery for an esophageal fistula resulting from enlargement of a residual false lumen of a thoracoabdominal aorta after second-stage TEVAR.

CONCLUSION

Hybrid procedures minimize surgical invasiveness in thoracic aortic aneurysm repair, but further evaluation of a larger number of patients is necessary.

Thoracic aortic aneurysms and dissections: endovascular treatment

The treatment of thoracic aortic disease has changed radically with the advances made in endovascular therapy since the concept of thoracic endovascular aortic repair was first described 15 years ago. Currently, there is a diverse array of endografts that are commercially available to treat the thoracic aorta. Multiple studies, including industry-sponsored and single-institution reports, have demonstrated excellent outcomes of thoracic endovascular aortic repair for the treatment of thoracic aortic aneurysms, with less reported perioperative morbidity and mortality in comparison with conventional open repair. Additionally, similar outcomes have been demonstrated for the treatment of type B dissections. However, the technology remains relatively novel, and larger studies with longer term outcomes are necessary to more fully evaluate the role of endovascular therapy for the treatment of thoracic aortic disease. This review examines the currently available thoracic endografts, preoperative planning for thoracic endovascular aortic repair, and outcomes of thoracic endovascular aortic repair for the treatment of both thoracic aortic aneurysms and type B aortic dissections. Mt Sinai J Med 77:256-269, 2010. (c) 2010 Mount Sinai School of Medicine.

Management of acute complicated and uncomplicated type B dissection of the aorta: focus on endovascular stent grafting

Endovascular repair of aortic dissection is the subject of multiple studies. This article aims to review the current literature on Type B complicated and uncomplicated dissection, including indications for medical therapy, open surgical therapy, and endovascular therapy. The review suggests a benefit for thoracic endovascular aortic repair in complicated dissection and medical therapy for uncomplicated dissection. Upcoming trials may shed more light on this issue.

Failed surgical ligation of the proximal left subclavian artery during hybrid thoracic endovascular aortic repair successfully managed by percutaneous plug or coil occlusion: a report of 3 cases

Open surgical rerouting and proximal ligation of one or more supra-aortic vessels prior to endovascular stent-graft placement has become an alternative to major open thoracic surgery in the treatment of complex thoracic aortic disease. Complications owing to failed surgical ligation of the left subclavian artery are rare. In this report, 3 cases of failed ligation are presented. Diagnosis was made by CT-scan and treatment was performed by transcatheter coil and plug embolization, avoiding redo neck surgery.

How to manage the left subclavian artery during endovascular stenting for thoracic aortic dissection? An assessment of the evidence

BACKGROUND

Despite the publication of recent guidelines for management of the left subclavian artery (LSA) during endovascular stenting procedures of the thoracic aorta, specific management for those presenting with dissection remains unclear. This systematic review attempts to address this issue.

METHODS

Systematic assessment of the published data on thoracic aorta dissection was performed identifying 46 studies, which incorporated 1,275 patients. Primary outcomes included the prevalence of left arm ischemia, stroke, spinal cord ischemia, endoleak, stent migration, and mortality. Outcomes were compared between patients with and without LSA coverage and revascularization incorporating factors such as the number of stents used, length of aorta covered, urgency of intervention, and type of dissection (acute or chronic). Statistical pooling techniques, χ(2) tests, and Fisher's exact testing were used for group comparisons.

RESULTS

As compared with other outcomes, LSA coverage without revascularization in the presence of aortic dissection is much more likely to be complicated by left arm ischemia (prevalence increased from 0.0% to 4.0% [p = 0.021]), stroke (prevalence increased from 1.4% to 9.0% [p = 0.009]), and endoleak (prevalence increased from 4.0% to 29.3% [p = 0.001]). However, revascularization was not shown to reverse these effects. Longer aortic coverage (≥ 150 mm) was associated with an increased prevalence of spinal cord ischemia (from 1.3% to 12.5% [p = 0.011]) and mortality (from 1.3% to 15.6% [p = 0.003]).

CONCLUSION

In patients undergoing endovascular stenting for thoracic aortic dissection, in cases where LSA coverage is necessary, revascularization should be considered before the procedure to avoid complications such as left arm ischemia, stroke, and endoleak, and where feasible, an appropriate preoperative assessment should be carried out.

Midterm results after endovascular treatment of acute, complicated type B aortic dissection

BACKGROUND

The purpose of this study was to assess the efficacy and midterm results of endovascular treatment of acute, complicated type B aortic dissection.

METHODS

Between January 2001 and February 2010, 32 patients (7 women, 25 men) with acute, complicated type B aortic dissection (mean age, 56 years; range, 35 to 83 years), defined as either aortic rupture, malperfusion, intractable pain, or uncontrolled hypertension, underwent endovascular stent graft placement with either the Gore Excluder/TAG device (n = 11), Medtronic Talent/Valiant device (n = 16), Bolton Relay (n = 2), or a combination of these stents (n = 3). Follow-up was 94% complete and averaged 26 ± 23 months.

RESULTS

Technical feasibility and success with deployment proximal to the entry tear was 87%, requiring partial or total coverage of the left subclavian artery (LSA) in 9 patients (28%). Hospital mortality was 12% ± 11% (95% confidence limit) with 2 late deaths (17 and 98 months after implant). Causes of hospital death included rupture in 2, retrograde type A dissection in 1, and multiorgan failure in 1 patient. Three patients (11%) experienced new neurologic complications (2 paraparesis and 1 hemiparesis). Six patients with malperfusion required branch vessel stenting. Furthermore, 2 had an early type Ia endoleak. Actuarial survival at 1 and 5 years was 81% and 76%, respectively. Freedom from treatment failure at 1 and 5 years (including reintervention, aortic rupture, device-related complication, and aortic related death) was 78% and 61%, respectively.

CONCLUSIONS

Endovascular stent-graft placement in acute, complicated type B aortic dissection proves to be a promising alternative therapeutic treatment modality in this relatively difficult patient cohort. Refinements, especially in stent design and application, may further improve the prognosis of patients in this life-threatening situation.

Long-term results of second-stage thoracic endovascular aortic repair following total aortic arch replacement

PURPOSE

We investigated the surgical results of secondary thoracic endovascular aneurysm repair (TEVAR) using the elephant trunk graft after total aortic arch replacement (TAR) for extensive thoracic aortic lesions.

METHODS

The subjects comprised 16 patients who underwent TEVAR as a staged procedure following TAR at our institution between 1997 and 2007. Long-term results were retrospectively surveyed (mean observation period 68.4 months). We performed TEVAR with the elephant trunk graft as a proximal landing zone for the descending thoracic repair, the mean duration between TAR and TEVAR was 4.7 weeks for the staged operations and 18.3 months for the nonstaged operations.

RESULTS

Early results were good in all cases, with no deaths and no noteworthy complications. For the seven patients without dissection, long-term results were also good. Among the nine patients with dissection, the false lumen in the thoracoabdominal area enlarged in three during follow-up. We performed thoracoabdominal repair in two, but one died of an aneurysm-esophageal fistula. There was only one long-term aneurysm-related death.

CONCLUSION

Second-stage TEVAR using the elephant trunk graft after TAR allows less invasive surgery for extensive aortic lesions and achieves good long-term results. However, enlargement of the false lumen was a long-term concern in patients with aortic dissection, and careful follow-up is essential.

Importance of Refractory Pain and Hypertension in Acute Type B Aortic Dissection

Background—

In patients with acute type B aortic dissection, presence of recurrent or refractory pain and/or refractory hypertension on medical therapy is sometimes used as an indication for invasive treatment. The International Registry of Acute Aortic Dissection (IRAD) was used to investigate the impact of refractory pain and/or refractory hypertension on the outcomes of acute type B aortic dissection.

Methods and Results—

Three hundred sixty-five patients affected by uncomplicated acute type B aortic dissection, enrolled in IRAD from 1996 to 2004, were categorized according to risk profile into 2 groups. Patients with recurrent and/or refractory pain or refractory hypertension (group I; n=69) and patients without clinical complications at presentation (group II; n=296) were compared. “High-risk” patients with classic complications were excluded from this analysis. The overall in-hospital mortality was 6.5% and was increased in group I compared with group II (17.4% versus 4.0%; P =0.0003). The in-hospital mortality after medical management was significantly increased in group I compared with group II (35.6% versus 1.5%; P =0.0003). Mortality rates after surgical (20% versus 28%; P =0.74) or endovascular management (3.7% versus 9.1%; P =0.50) did not differ significantly between group I and group II, respectively. A multivariable logistic regression model confirmed that recurrent and/or refractory pain or refractory hypertension was a predictor of in-hospital mortality (odds ratio, 3.31; 95% confidence interval, 1.04 to 10.45; P =0.041).

Conclusions—

Recurrent pain and refractory hypertension appeared as clinical signs associated with increased in-hospital mortality, particularly when managed medically. These observations suggest that aortic intervention, such as via an endovascular approach, may be indicated in this intermediate-risk group.

Emergency endovascular repair of complicated Stanford type B aortic dissections within 24 hours of symptom onset in 30 cases

OBJECTIVE

To investigate the results of emergency endovascular repair of complicated Stanford type B aortic dissections within 24 hours of symptom onset.

METHODS

A retrospective analysis of the clinical data of 30 patients with complicated Stanford type B aortic dissections who underwent emergency endovascular repair between June 2007 and October 2008. Endovascular repairs were performed within 24 hours of symptom onset. Stent-grafts were deployed at the first entry tear through the femoral artery under fluoroscopic guidance. Follow-up computed tomography scans were performed at 1, 3, 6, 12, and 18 months after treatment.

RESULTS

The mean patient age was 64 years (range, 43-83 years). There were 3 cases associated with rupture, 6 cases associated with refractory hypertension, 15 cases associated with persistent pain, 2 cases associated with retrograde dissection, and 4 cases associated with malperfusion. The technical success rate was 100%, and the incidence of immediate postoperative endoleaks was 13.4%. One patient died of dissection rupture within 30 days. The mean follow-up period was 12 ± 8 months. A small, persistent endoleak (<10%) occurred in 1 patient, and 1 patient died of acute liver failure 2 months after the operation. No stent dislocation, false lumen expansion, or paraplegia occurred. The false lumen was completely thrombosed in 6 patients and partially thrombosed in 19 patients. The mortality rate was 6.67%.

CONCLUSIONS

Our results suggest that emergency endovascular repair of complicated Stanford type B aortic dissections within 24 hours of symptom onset is associated with good outcomes and can decrease mortality.

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.

Randomized comparison of strategies for type B aortic dissection: the INvestigation of STEnt Grafts in Aortic Dissection (INSTEAD) trial

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) represents a novel concept for type B aortic dissection. Although life-saving in acute emergencies, outcomes and survival of TEVAR in stable dissection are unknown.

METHODS AND RESULTS

One hundred forty patients in stable clinical condition at least 2 weeks after index dissection were randomly subjected to elective stent-graft placement in addition to optimal medical therapy (n=72) or to optimal medical therapy alone (n=68) with surveillance (arterial pressure according to World Health Organization guidelines < or =120/80 mm Hg). The primary end point was all-cause death at 2 years, whereas aorta-related death, progression (with need for conversion or additional endovascular or open surgery), and aortic remodeling were secondary end points. There was no difference in all-cause deaths, with a 2-year cumulative survival rate of 95.6+/-2.5% with optimal medical therapy versus 88.9+/-3.7% with TEVAR (P=0.15); the trial, however, turned out to be underpowered. Moreover, the aorta-related death rate was not different (P=0.44), and the risk for the combined end point of aorta-related death (rupture) and progression (including conversion or additional endovascular or open surgery) was similar (P=0.65). Three neurological adverse events occurred in the TEVAR group (1 paraplegia, 1 stroke, and 1 transient paraparesis), versus 1 case of paraparesis with medical treatment. Finally, aortic remodeling (with true-lumen recovery and thoracic false-lumen thrombosis) occurred in 91.3% of patients with TEVAR versus 19.4% of those who received medical treatment (P<0.001), which suggests ongoing aortic remodeling.

CONCLUSIONS

In the first randomized study on elective stent-graft placement in survivors of uncomplicated type B aortic dissection, TEVAR failed to improve 2-year survival and adverse event rates despite favorable aortic remodeling.

Thoracic aortic dissection: long-term results of endovascular and open repair

Treatment paradigms for aortic dissection are based upon the types of complications with which the patients present. For acute uncomplicated dissection, medical therapy is preferred. Endovascular repair is preferred for patients with acute distal dissection complicated by end-organ malperfusion, rupture, or aneurysmal degeneration. For patients with chronic dissection with aneurysm, open repair is preferred if safe, and endovascular treatment should be limited to highest-risk patients because of the uncertainty of success with this approach. For intermediate-risk patients, hybrid repairs provide a good alternative. Ultimately, improvement in long-term outcomes after treatment of aortic dissection still depends on prevention of end-organ ischemia and aneurysmal degeneration of the chronically dissected distal aorta. Although the evidence base for the roles of various approaches is lacking, data currently being accrued and must be closely analyzed to better estimate both the short- and long-term benefits of these complementary treatment strategies.

Endovascular repair or medical treatment of acute type B aortic dissection? A comparison

INTRODUCTION

The aim of this retrospective study was to compare the outcome of thoracic endovascular aortic repair (TEVAR) to that of medical therapy in patients with acute type B aortic dissection (TBD).

MATERIALS AND METHODS

From July 1996 to April 2008, 88 patients presenting with acute TBD underwent either TEVAR (group A, n=38) or medical therapy (group B, n=50). Indications for TEVAR were intractable pain, aortic branch compromise resulting in end-organ ischemia, rapid aortic dilatation and rupture. Follow-up was performed postinterventionally, at 3, 6 and 12 months and yearly thereafter and included clinical examinations and computed tomography (CT), as well as aortic diameter measurements and assessment of thrombosis.

RESULTS

Mean follow-up was 33 months in group A and 36 months in group B. The overall mortality rate was 23.7% in group A and 24% in group B, where 4 patients died of late aortic rupture. In group A, complications included 9 endoleaks and 4 retrograde type A dissections, 3 patients were converted to open surgery and 2 needed secondary intervention. None of the patients developed paraplegia. In group B, 4 patients were converted to open surgery and 2 to TEVAR. The maximal aortic diameter increased in both groups. Regarding the extent of thrombosis, our analyses showed slightly better overall results after TEVAR, but they also showed a tendency towards approximation between the two groups during follow-up.

CONCLUSION

TEVAR is a feasible treatment option in acute TBD. However, several serious complications may occur during and after TEVAR and it should therefore be reserved to patients with life-threatening symptoms.