Endovascular management of acute aortic dissections

Management of Acute, Complicated Type B Aortic Dissection

Management of acute complicated Type B aortic dissection (TBAD) requires a multidisciplinary approach with careful evaluation and understanding of the complicating features. Patients who present with or progress to a complicated TBAD must be triaged and managed rapidly due to the high morbidity and mortality even in the presence of optimal medical, endovascular, and open therapies. When required, invasive therapies can be broken down most simply into four treatments: thoracic endograft placement, aortic fenestration, branch vessel stenting, and open repair. However, which therapy to offer and in which order is often unclear. In this review, focus is placed on clinical presentation, diagnosis, and explanation for one or a combination of these therapies. In addition, contraindications as well as expected outcomes, complications, and adjunct therapies will be reviewed. The advent of advanced endovascular techniques has certainly improved the immediate morbidity and mortality of acute complicated TBAD; however, much remains to learn about patient selection and therapeutic intervention performed.

Adjunctive branch interventions during thoracic endovascular aortic repair for acute complicated type B dissection are not associated with inferior outcomes

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) has been shown to effectively treat malperfusion associated with acute type B thoracic aortic dissection (TBAD). A subset of patients might still require adjunctive peripheral or visceral artery branch interventions during TEVAR to remedy persistent end organ malperfusion. Our objectives were to determine the incidence of these adjunctive interventions and to compare the outcomes between patients who had and had not undergone such interventions.

METHODS

We performed a retrospective review of the TEVAR and complex EVAR module of the Vascular Quality Initiative from 2010 to 2019 to identify all patients treated for malperfusion due to acute TBAD. The anatomic branch and procedure performed at TEVAR were recorded. The 30-day mortality, need for reintervention, complication rates, and overall survival were compared between these patients stratified by adjunctive intervention status.

RESULTS

A total of 426 patients had undergone TEVAR for acute TBAD with end organ malperfusion. Of the 426 patients, 126 (29.6%) had undergone 182 adjunctive branch interventions during TEVAR. The most common interventions were stenting (n = 86; 47.3%) and stent grafting (n = 49; 26.9%), with the most common site being the left renal artery (n = 49; 26.9%). The patients in both groups had similar 30-day mortality (12.4% with branch intervention vs 15.6% without; P = .511) and rates of in-hospital reintervention (19.2% with branch intervention vs 20.7% without; P = .732). No differences were found in the rates of postoperative complications or overall survival at 3 years between the two groups.

CONCLUSIONS

Adjunctive peripheral and visceral artery branch interventions in conjunction with TEVAR for acute TBAD with malperfusion occurred in one third of index cases, but did not predispose patients to worse overall outcomes. Adjunctive arterial branch interventions should be included in the treatment paradigm for acute TBAD with end organ malperfusion that does not improve with primary entry tear coverage alone.

[Choice of optimal treatment policy in patients with descending aortic dissection]

Contemporary approaches to treatment of patients with dissection of the descending aorta (DA), as well as the data of international registries and guidelines are contradictory. The endovascular method of treatment of patients with descending aortic dissection has been recognized to be revolutionary. However, there seems to be no commonly accepted concept concerning appropriate use of currently available techniques of treating patients with DA dissection. This study was aimed at analysing the experience gained in using various methods of treatment of patients with descending aortic dissection (DAD). We retrospectively examined the results of surgical treatment of 78 patients with DAD. Of these, 45 patients were found to have Stanford type B dissection and 33 patients had type A dissection, who underwent treatment during ten years from January 2008. The decision concerning the type of care for patients with DAD (conservative, surgical, endovascular or combined methods of treatment) directly depends on the patient's state stability, technical feasibility of the intended procedure, and the presence of concomitant pathology. The findings obtained in our study demonstrated better immediate outcomes of the endovascular approach compared with the hybrid and surgical ones. In order to achieve complete haemodynamic correction of the pathology, to minimize the risk of aortic remodelling and the development of aorta-related complications, the treatment should not be limited to endoprosthetic repair of the thoracic portion of the DA with a stent graft, but should rather be supplemented with stenting of more distal segments, including with uncoated stents at the level of the visceral branches. Only such staged approach may provide better conditions for obliteration of the aortic false lumen and formation of a 'neo-frame' of the aortic wall.

Aortic Dissection: Accurate Subintimal Flap Fenestration by Using a Reentry Catheter with Fluoroscopic Guidance-Initial Single-Institution Experience

PURPOSE

To evaluate the feasibility, effectiveness, and safety of using a commercially available reentry catheter with fluoroscopic guidance to gain controlled target lumen reentry for fenestration in patients with aortic dissection.

MATERIALS AND METHODS

This retrospective study was approved by the local institutional review board; informed consent was waived. Between April 2009 and December 2013, 13 consecutive patients (10 men and three women; mean age, 51.2 years; range, 30.0-77.0 years; mean age of women, 47.0 years; range, 30.0-69.0 years; mean age of men, 52.4 years; range, 35.0-77.0 years) with aortic dissection and spinal (n = 4), renal (n = 7), mesenteric (n = 2), and/or iliofemoral (n = 9) malperfusion syndrome were included. All patients received target lumen reentry by means of balloon fenestration of the aortic dissection flap. A reentry catheter was used for fluoroscopically guided puncture of the target lumen. Technical success, clinical outcome, Stanford type of dissection, procedure time, number of fenestrations of the intimal flap per patient, necessity of additional aortic stent-graft implantation and/or placement of a bare metal stent, complications, and follow-up images were evaluated. Pre- and postinterventional systolic blood pressure gradients between the true lumen and the false lumen were compared (Wilcoxon signed-rank test). Safety of the reentry catheter maneuver was estimated with the Clopper-Pearson method.

RESULTS

Use of the reentry catheter was technically successful in all 13 (100%) patients and clinically successful in 10 of 13 (77%) patients. Four patients had type A and nine had type B dissection. The mean clinical follow-up period was 14.2 months. Median procedure time was 71 minutes. In four patients, fenestration of the intimal flap was performed twice. Three patients underwent additional aortic stent grafting, four patients underwent placement of an iliofemoral stent, and one patient underwent placement of a carotid artery stent. Blood pressure gradients between the true lumen and the false lumen were significantly reduced (P = .0313). One patient who had a combination of syndromes died of multiorgan failure.

CONCLUSION

The applied commercially available reentry catheter seems to be a reliable and safe tool that may be useful for gaining target lumen reentry with reasonably good clinical outcomes.

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.

Treatment of acute type-B aortic dissection: thoracic endovascular aortic repair or medical management alone?

OBJECTIVES

This study sought to evaluate the early and long-term effect of thoracic endovascular aortic repair (TEVAR) on type-B acute aortic dissection (AAD).

BACKGROUND

Uncomplicated type-B AAD is generally treated with medical management; complicated dissections require surgery or TEVAR. Studies have demonstrated that long-term outcomes with medical management are suboptimal. Therefore, we sought to determine the long-term effect of TEVAR compared with medical management alone on type-B AAD.

METHODS

From January 2004 to May 2008, 193 consecutive patients in 2 hospitals were treated and retrospectively placed into 1 of 2 groups: 1) the TEVAR group-type-B AAD treated with TEVAR and antihypertensive medications (n = 152); and the 2) medicine group-uncomplicated type-B AAD treated medically alone (n = 41). All TEVAR procedures were performed in the acute phase.

RESULTS

There were no significant differences in demographics, comorbidity profiles, or early events between groups. The cumulative freedom from all late adverse events at 1, 3, and 5 years was 97%, 89%, and 67% in the TEVAR group and 97%, 63%, and 34% in the medicine group. Log-rank tests showed that medically treated patients had more late adverse events than TEVAR-treated patients did (p = 0.003). The 5-year cumulative survival rate from all-cause death was not significantly different between the 2 groups.

CONCLUSIONS

Patients with type-B AAD treated with TEVAR experienced fewer late adverse events than those treated with medical management, but there was no significant difference among the groups in 5-year mortality rates. Further studies of longer-term survival rates are needed to determine whether TEVAR could be an effective treatment for type-B AAD.

Acute aortic emergencies--part 2: aortic dissections

Patients with aortic disease are some of the highest acuity patients that emergency clinicians encounter. Dissection is the most common aortic catastrophe and involves separation of the aortic layers in a longitudinal fashion leading to diminished perfusion and systemic ischemia. Characteristics of pain, branch vessel involvement, and incidence lead to an understanding of patient presentation, morbidity, and mortality. Diagnosis, selection of diagnostic studies, the degree of preoperative ischemia, and risk of operative mortality can be accomplished using validated clinical decision tools. Emergency interventions are guided by the type of dissection according to the Stanford classification system. Medical management includes pain control and anti-impulse, antihypertensive therapy through vasodilatation and blockage of the sympathetic β-response. The patient may then be evaluated for open surgical intervention, aortic fenestration, endovascularly placed stent grafts, or a combination possibly in a staged approach. Morbidity includes rupture, stroke, paraplegia, acute renal failure, bowel ischemia, and peripheral ischemia.

Acute type a aortic dissection: for further improvement of outcomes

Despite improved outcomes of acute type A aortic dissection (AAAD), many patients die at the moment of onset, and hospital mortality is still high. This article reviews the latest literature to seek the best possible way to optimize outcomes. Delayed diagnosis is caused by variation in or absence of typical symptoms, especially in patients with neurological symptoms. Misdiagnosis as acute myocardial infarction is another problem. Improved awareness by physicians is needed. On arrival, quick admission to the OR is desirable, followed by assessment with transesophageal echocardiography, and malperfusion already exists or newly develops in the OR; thus, timely diagnosis without delay with multimodality assessment is important. Although endovascular therapy is promising, careful introduction is mandatory so as not to cause complications. While various routes are used for the systemic perfusion, not a single route is perfect, and careful monitoring is essential. Surgical treatment on octogenarians is increasingly performed and produces better outcomes than conservative therapy. Complications are not rare, and consent from the family is essential. Prevention of AAAD is another important issue because more patients die at its onset than in the following treatment. In addition to hereditary diseases, including bicuspid aortic valve disease, the management of blood pressure is important.

Progress in management of malperfusion syndrome from type B dissections

OBJECTIVE

Malperfusion syndrome is a known predictor of poor outcomes in acute type B dissection. We describe our experience with revascularization in the acute setting.

METHODS

Patients undergoing intervention for ischemia complicated acute type B dissection between November 1999 and March 2011 were reviewed. Details of presenting condition, surgical intervention, and postoperative course were collected. Descriptive and inferential statistical analyses included survival and freedom from reintervention using Cox proportional hazards models.

RESULTS

A total of 61 patients were identified with malperfusion in at least one territory, including spinal cord 7/61 (12%), mesenteric 37/61 (61%), renal 45/61 (73%), and lower extremity 38/61 (62%). Thoracic stent grafts were placed in all patients, and 41% of patients required adjunctive branch vessel stenting. After intervention, resolution of the ischemia was reported in 57/61 (93%) of patients. The 30-day/in-hospital mortality was 21.3%. The 6-month, 1-year, and 5-year survival was 75% (95% CI, 65%-87%), 71% (95% CI, 61%-84%), and 56% (95% CI, 43%-74%), respectively. The 6-month, 1-year, and 5-year freedom from reintervention was 84% (95% CI, 75%-95%), 76% (95% CI, 65%-90%), and 42% (95% CI, 24%-76%), respectively. Territory of ischemia was not independently associated with mortality, but placement of a stent graft proximal to the subclavian artery was associated with poor outcome hazard ratio 2.91 (95% CI, 1.09-8.11; P = .034).

CONCLUSIONS

Malperfusion in any territory at the time of presentation in patients with type B dissections can be treated with endovascular intervention with acceptable outcomes. Opposed to branch vessel intervention alone, increased aortic intervention with regard to proximal coverage may signify more serious disease is associated with worse outcome.