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

A Systematic Review and Meta-Analysis of Current Evidence Related to the Impact of Endovascular Repair Timing on Prognosis of Acute Stanford Type B Aortic Dissection

BACKGROUND

The objective of this study was to determine whether thoracic endovascular aortic repair (TEVAR) timing is more beneficial in the acute phase (first 14 days) than in the subacute phase (14-90 days) for the administration of acute Stanford type B aortic dissection (TBAD).

METHODS

A comprehensive literature search was conducted in databases (EMBASE, PubMed and Cochrane Library) until December 2023 to identify studies reporting the results of TEVAR used for patients with acute TBAD. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated utilizing either the random-effects model or the fixed-effects model.

RESULTS

A total of 25 studies involving 4,827 individuals with TBAD (including 1,609 with subacute TBAD) met our selection criteria. Early results revealed a lower incidence of Ia endoleaks (OR, 1.55; 95% CI, 1.03-2.33; P = 0.04) and aortic ruptures (OR, 2.89; 95% CI, 0.98-8.50; P = 0.05) in subacute TBAD. Apart from these findings, there was little difference in other incidents between the 2 groups. Regarding late outcomes, we observed significantly higher rates of retrograde dissection (OR, 2.12; 95% CI, 1.04-4.34; P = 0.04), distal stent-induced new entry (OR, 2.39; 95% CI, 1.24-4.61; P = 0.009), and reintervention (OR, 1.45; 95% CI, 0.05-1.99; P = 0.02) in acute TBAD than in subacute TBAD, whereas no significant differences were found for other outcomes between the 2 groups. Also, TEVAR appeared to yield comparable results for false lumen thrombosis and true lumen regression in both groups.

CONCLUSIONS

Subacute TBAD repair with TEVAR demonstrates a more effective reduction in adverse event rates compared to immediate treatment in the acute phase.

Hotspots and development frontiers of postoperative complications of AD: Bibliometric analysis - a review

The research on the postoperative complications of aortic dissection (AD) has received great attention from scholars all over the world, and the number of research articles in this field has consistently increased year after year. However, no bibliometric reports have been published yet to analyze the scientific output and the current situation in this field. The Bibliometrix R-package, VOSviewer, and CiteSpace software were used to conduct a bibliometric analysis of the hotspots and development frontiers of AD. A total of 1242 articles were retrieved. The USA, China, and Japan had the highest number of publications. The five keywords with the highest frequency were "analysis," "incidence," "acute type," "graft," and "risk factor." The results also indicated that the research in related fields had shifted from surgical treatment and utilizing experience to the evidence-based exploration of risk factors and the construction of prediction models to help better manage postoperative complications of AD. This is the first bibliometric analysis of global publications on the postoperative complications of AD. The current research hotspots focus on three areas: common postoperative complications of AD, exploration of the related risk factors, and management of complications. Future research could focus on identifying risk factors through meta-analysis and using a multicenter database for AD as well as building relevant models to predict the development of complications to better facilitate the clinical management of AD patients.

TEVAR for complicated and uncomplicated type B aortic dissection-Systematic review and meta-analysis

BACKGROUND

Type B aortic dissection (TBAD), is defined as a dissection involving the aorta distal to left subclavian artery with the ascending aorta and the aortic arch not affected. TBAD is classified due to the time frame and presence of complications. Complicated TBAD (co-TBAD) patients have a greater mortality rate than uncomplicated TBAD (un-TBAD) and thoracic endovascular aortic repair (TEVAR) is considered the gold-standard intervention for these clinical challenges.

METHODS

We undertook a systematic review of the literature regarding TEVAR intervention in co-TBAD and un-TBAD. A comprehensive search was undertaken across four major databases and was evaluated and assessed until June 2020.

RESULTS

A total of 16,104 patients were included in the study (7772 patients co-TBAD and 8352 un-TBAD). A significantly higher proportion of comorbidities were seen in co-TBAD patients compared with un-TBAD. Acute dissection was more frequent in the co-TBAD group (73.55% vs. 66.91%), while chronic dissection was more common in un-TBAD patients (33.8% vs. 70.73%). Postprocedure stroke was higher in co-TBAD (5.85% vs. 3.92%; p < .01), while postprocedural renal failure was higher in un-TBAD patients (7.23 vs. 11.38%; p < .01). No difference was observed in in-hospital mortality however the 30 days mortality was higher in the co-TBAD group. One-year survival was higher in the uncomplicated group but this difference was not observed in the 5-year survival.

CONCLUSION

In our analysis we can appreciate that despite significantly higher comorbidities in the co-TBAD cohort, there was no difference in in-hospital mortality between the two groups and the 5-year survival did not have any difference.

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.

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.

Repair of Acute Type B Aortic Dissection Complicated by Aortic Rupture with Debranching Thoracic Endovascular Aortic Repair and Left Subclavian Artery Occlusion Using Amplatzer Vascular Plug II

An 88-year-old man with severe chest pain and syncope was admitted to our hospital. Contrast-enhanced computed tomography (CT) revealed acute type B aortic dissection with rupture. Considering age and operative risk, we performed emergency thoracic aortic endovascular repair with two-debranching of the left common carotid and left subclavian arteries. To prevent type II endoleak, we used Amplatzer Vascular Plug (AVP) II for left subclavian artery embolization. Postoperative contrast-enhanced CT showed no type II endoleak and rupture site exclusion. As postoperative persistent blood flow to the primary entry or rupture site causes re-rupture, AVP II was crucial in preventing type II endoleak.

Management of complicated and uncomplicated acute type B dissection. A systematic review and meta-analysis

BACKGROUND

The management of acute type B dissection represents a clinical challenge. We undertook a systematic review of the available literature regarding medical, surgical and endovascular treatments of acute type B aortic dissection and combined the eligible studies into a meta-analysis.

METHODS

An extensive electronic health database search was performed on all articles published from January 2006 up to November 2013 describing the management of acute type B aortic dissection. Studies including less than 15 patients were excluded.

RESULTS

ACUTE COMPLICATED TYPE B DISSECTION: overall, 2,531 patients were treated with endovascular repair (TEVAR) and the pooled rate for 30-day/in-hospital mortality was 7.3%. The pooled estimates for cerebrovascular events, spinal cord ischemia (SCI) and total neurologic events were 3.9%, 3.1% and 7.3%, respectively. A total of 1,276 patients underwent open surgical repair and the pooled rate for 30-day/in-hospital mortality was 19.0%. The pooled rate for cerebrovascular events was 6.8%, for SCI 3.3% and for total neurologic complications 9.8%. Acute uncomplicated type B dissection: outcome of 2,347 patients who underwent conservative medical management were analyzed. The pooled 30-day/in-hospital mortality rate was 2.4%. The pooled rate for cerebrovascular events was 1%, for SCI 0.8% and for overall neurologic complications 2%.

CONCLUSIONS

Endovascular repair provides a superior 30-day/in-hospital survival for acute complicated type B aortic dissection compared to surgical aortic reconstruction. However, open repair still has a significant role as endovascular repair is not applicable in all patients and there remains concerns regarding the durability of this technique. TEVAR seems to have a more favorable outcome regarding aortic remodeling and the aortic-specific survival rate when compared with medical therapy alone. Randomized controlled trials focusing on the prognostic factors of early and late complications in uncomplicated type B dissections are needed.

Acute renal injury after thoracic endovascular aortic repair of Stanford type B aortic dissection: incidence, risk factors, and prognosis

BACKGROUND/PURPOSE

Acute kidney injury (AKI) significantly increases the risk of mortality in patients following cardiovascular intervention procedures. This study was carried out to investigate the incidence, predictors, and prognostic implications of AKI after thoracic endovascular aortic repair (TEVAR) of Stanford type B aortic dissection.

METHODS

A total of 156 patients with Stanford type B aortic dissection who underwent TEVAR were retrospectively analyzed between February 1, 2004 and October 31, 2011. Multivariable regression was used to predict risk factors for AKI. Association between baseline characteristics, postoperative AKI, and mortality during follow up was evaluated.

RESULTS

AKI was identified in 48 (30.8%) of 156 patients, with seven (14.5%) patients requiring continuous renal replacement therapy. The in-hospital mortality rate was 0% in patients without AKI and 12.5% in those with AKI (p = 0.001). Univariate analysis identified preoperative chronic kidney disease, acute dissection, complicated dissection, malperfusion complications with comprehensive complications, and postoperative minimum estimated glomerular filtration rate within 48 hours as associated with AKI. Malperfusion complications [odds ratio (OR) = 4.828; 95% confidence interval (CI) = 1.163-20.03] were the only independent predictor of AKI. Patients suffering from AKI had a 14-fold increased risk for 30-day mortality (OR = 14.3; 95% CI = 1.7-118.4; p = 0.014) and a 10-fold increased risk for 1-year mortality (OR = 9.5; 95% CI = 2.02-44.9; p = 0.004).

CONCLUSION

A significant rate of AKI was observed following TEVAR and was associated with an increase in 30-day and 1-year mortality. Malperfusion complications were identified as an independent predictor of AKI.

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.

Placement of Endovascular Stent Graft in Acute Malperfusion Syndrome After Acute Type II Aortic Dissection

Acute malperfusion syndrome is a serious complication of acute aortic dissection. A 76-year-old female patient was admitted with acute type B aortic dissection and developed renal malperfusion during medical therapy. We are reporting a clinically successful result from the thoracic endovascular aortic repair used for malperfusion syndrome that occurred by acute type B aortic dissection.

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.

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.

Acute aortic dissection

We summarise advances in the epidemiology, presentation, pathogenesis, diagnosis, and management of acute aortic dissection. Improved understanding of this problem has been assisted not only by establishment of an international registry but also by progress in molecular biology and genetics of connective-tissue diseases. Advances in endovascular products and techniques have provided new treatment options. Open surgical repair remains the main treatment for dissection in the ascending aorta, whereas endovascular treatment is increasingly being used in dissection that is limited to other parts of the aorta.