Is Multilayer Bare Stent Safe or Effective for the Treatment of Aortic Aneurysms? A Meta-analysis with Early and Mid-term Outcomes

Atrial septal defect occluder combined with stent graft for the management of post-dissection aortic aneurysm previously treated with unsuccessful coils: a case report

BACKGROUND

Although the candy-plug technique has been reported to be useful for the treatment of post-dissection aortic aneurysm, the stent graft needs be to customized to accommodate the size of vascular occluders.

CASE PRESENTATION

We present a case of a persistent false lumen successfully treated with endovascular stent-graft and atrial septal defect occluder in a patient with Stanford Type B dissection. A covered stent graft was implanted into the false cavity through a distal rupture, and an atrial septal defect occluder was inserted into the covered stent to seal of the false cavity. Decreased aneurysmal diameter and false lumen thrombosis were noted by CT scan at 6-month follow-up.

CONCLUSIONS

Our case showed that combined use of a stent graft and atrial septal defect occluder is safe, technically feasible and effective in sealing of the false lumen in post-dissection aortic aneurysm patients with previously failed false lumen thrombosis.

Endovascular treatment of complicated aortic aneurysms using a modified flow-diverting strategy: Mid- to long-term outcome from a multicenter cohort study

OBJECTIVES

Frequently reported adverse events following flow-diverting stents' treatment of aortic aneurysms indicate further refinements of this technique are required. This study aims at evaluating the clinical efficacy of an improved flow-diverting strategy.

METHODS

A modified flow-diverting procedure was utilized in selected patients, in which stent-grafts were used to cover the non-branched segment of the aneurysmal lesion while flow-diverting multilayered bare metal stents were applied to cover the reno-visceral segment. The safety and efficacy of this joint procedure were assessed by regular follow-up.

RESULTS

We screened 497 patients and included 67 cases (mean age: 67.07 ± 12.14 years; 53 males) between February 2012 and March 2018. The median number of stent-grafts and bare metal stents used in the procedure were 1 (range: 1 to 3) and 3 (range: 2 to 4), respectively. During a mean follow-up period of 34.54 ± 20.28 months, aneurysm maximum diameter decreased from 64.79 ± 10.31 to 59.32 ± 10.20 mm (p = 0.002), while sac thrombosis ratio increased from 26.01±10.99% to 98.46±4.84% (p<0.001). Aneurysm-related death or conversion to open repair was documented in three patients. The majority side-branches (198/201) remained patent during follow-up. Overall clinical success rate reached 91.04% (61/67).

CONCLUSIONS

The joint procedure is characterized by significant aneurysm thrombosis along with high aneurysm stabilization/shrinkage and side-branches' patency rate. It might represent a potential improvement of the flow-diverting strategy in treating complex aortic lesions, yet large-scale, prospective, and randomized trials are anticipated to draw a robust conclusion.

ADVANCES IN KNOWLEDGE

The joint procedure could potentially exclude complex aortic aneurysms from circulation while maintaining the collateral branches.

Alternative management of proximal aortic dissection: concept and application

Open surgery remains the mainstay of treatment for acute type A aortic dissection and should be offered to most patients. However, there are elderly patients in which surgical treatment may be deemed extremely high risk or futile. Endovascular treatment approaches have been applied to a small number of these patients and data are limited to case reports and small series. The application of endovascular therapies to ascending aorta is currently limited by anatomical and technical challenges posed by the dynamic motion of the ascending aorta and the proximity of vital structures to intended landing zones (aortic valve, coronary arteries, and supra-aortic branches) and lack of specially designed endografts to address these issues. While thoracic endovascular aortic repair (TEVAR) has replaced open aortic repair for a suitable lesion in distal aortic dissection, some selected patients with type A aortic dissection at high surgical may be candidates. Hence, there is potential because, in proximal (Stanford type A) dissections, 10–30% of patients are not accepted for surgery, and 30–50% are technically amenable for TEVAR. Recent experience has shown that carefully selected patients with favorable anatomical characteristics may be subject to endovascular stent-graft treatment as a last resort with mixed results. Technical improvement is necessary to offer. satisfactory endovascular options in non-surgical candidates.

Hemodynamic Effects of Multiple Overlapping Uncovered Stents on Aortic Dissection: Surgical Strategies and Implications for False Lumen Thrombosis

PURPOSE

Multiple overlapping uncovered stents (MOUS) are employed to promote false lumen thrombosis in the aortic dissections (AD), when the tears are in close vicinity to the branch vessels. However, the overall rate of false lumen thrombosis remains unsatisfactory. This study was performed to investigate the hemodynamic influence of MOUS on aortic dissection to shed some light on the mechanism of post-stenting false lumen thrombosis.

METHODS

An anatomically accurate computational fluid dynamics model was developed to investigate the hemodynamics of AD. A parametric study was carried out to demonstrate the hemodynamic influence of MOUS in various post-surgery scenarios featuring the representative surgical strategies involving MOUS.

RESULTS

The use of reduced-porosity MOUS slowed the blood flow in the false lumen and decreased the wall shear stress. MOUS depressed the false lumen and enlarged the true lumen, without significantly altering the blood outflow distribution among the branch vessels. Compared with MOUS-alone and stent graft-alone scenarios, the combination of MOUS and stent graft generated a substantially large region of stagnant flow. The active flow was confined to an area in close vicinity to the tears covered by the MOUS, which perfuse the right renal artery in the false lumen.

CONCLUSIONS

MOUS helps to generate a favored hemodynamic environment for thrombus formation in the false lumen. Application of MOUS along with covered stent grafts may represent a more effective treatment for AD than utilizing MOUS or stent graft alone.

Treatment of aortic dissecting aneurysm involving visceral arteries with multi-layer bare stents

OBJECTIVE

Aortic dissecting aneurysms involving visceral arteries are difficult for clinical treatment. This study aimed to explore the clinical efficacy and safety of multi-layer bare stents technique in the treatment of aortic dissecting aneurysms involving visceral arteries.

METHOD

The clinical data of 16 patients of aortic dissecting aneurysm involving visceral artery treated with multi-layer bare stents technique from March 2013 to March 2017 in Tianjin Medical University General Hospital were retrospectively analyzed. To explore the clinical efficacy, the number of stents applied, postoperative aortic dissecting thrombosis and postoperative cumulative branch arterial patency of the16 patients.

RESULTS

The operations of the 16 patients were successfully completed without peri-operative death cases. The 16 patients were implanted with 39 bare stents with an average of 2.44 per person. There were 2 cases with 1 stent, 8 cases with 2 stents and 7 cases with 3 stents. One month after the operation, CTA showed complete thrombosis in the arterial dissection in 4 cases (25.0%), partial thrombosis in 12 cases (75.0%); CTA showed that celiac artery, left and right renal arteries, and superior mesenteric artery were all unobstructed. There were 4 cases (25.0%) of dissecting artery with reduced diameter, 12 patients (75.0%) without changes in the diameter, and no diameter expanding cases.

CONCLUSION

The treatment for aortic dissecting aneurysm involving the visceral arteries using multi-layer bare stents technique is safe and reliable with a higher patency rate of postoperative accumulated branch arteries.

Endovascular Treatment of Patients with Isolated Mesenteric Artery Dissection Aneurysm: Bare Stents Alone Versus Stent Assisted Coiling

OBJECTIVE

The aim was to evaluate the outcomes of endovascular treatment with bare stents alone versus stent assisted coiling in isolated mesenteric artery dissection (IMAD) aneurysms.

METHODS

Patients with an IMAD aneurysm who underwent endovascular stenting between February 2010 and February 2017 at one of three institutions were included in this study. Data regarding technical success, procedure time, symptom resolution, complications, changes in IMAD aneurysm, and stent patency were recorded.

RESULTS

A total of 38 patients (35 men) were included, 27 treated with bare stents alone and 11 treated with stent assisted coiling. Technical success was achieved in 100% of patients treated with bare stents and in 81.8% of those treated with stent assisted coiling (p = 0.078). The mean procedure times were 62.6 ± 5.3 min for treatment with bare stents and 116.4 ± 8.4 min for stent assisted coiling (p < 0.001). A total of 23 patients had persistent symptoms before stenting; all symptoms were resolved within 3.0 ± 0.7 days. No procedure related major complications occurred. Over 30.2 ± 18.1 months of follow up, complete resolution of the IMAD aneurysm was achieved in all patients; good stent patency and in stent re-stenosis were achieved in 65.8% and 34.2% patients, respectively. There were no occlusions of the stented arteries.

CONCLUSIONS

Bare stents alone and stent assisted coiling have high technical success rates and demonstrate good intermediate patency in patients with an IMAD aneurysm. Bare stents alone may serve as an alternative to stent assisted coiling for the management of IMAD aneurysm.

[Staged approach for hybrid thoracoabdominal aortic replacement]

AIM

To generalize our experience of step-by-step hybrid thoracoabdominal aortic replacement.

MATERIAL AND METHODS

Twenty-three patients were enrolled who underwent staged hybrid treatment of thoracoabdominal aortic aneurysm. There were 5 (21.7%) women and 18 (78.3%) men aged 61.4±8.3 years (37-74 years). The first stage was proximal debranching, the second - distal (abdominal) procedure and the third - stenting of the thoracoabdominal aorta.

RESULTS

There were no any complications after proximal debranching and aortic stenting. Abdominal debranching was followed by lethal outcome in 3 (13.0%) patients and early postoperative occlusion of the prosthesis brunch in 3 out of 87 cases.

CONCLUSION

Staged approach for hybrid surgical treatment is optimal solution, especially in high risk patients. In our opinion no necessity for cardiopulmonary bypass is the main advantage of this technique.