A systematic review and meta-analysis of the streamliner multilayer flow modulator stent for treatment of complex aortic lesions

OBJECTIVE

We evaluated the safety and efficacy of multilayer flow modulator (MFM) stents (Cardiatis, Isnes, Belgium) for the treatment of complex aortic lesions.

METHODS

A systematic electronic research was conducted for studies reported from December 2008 to May 2020. Data extracted from 15 eligible case series (CS) were appropriately pooled and analyzed in a meta-analysis. The patient baseline characteristics were recorded, and 16 outcomes of interest were studied. The primary end points included 30-day all-cause and aneurysm-related mortality, aneurysm-related mortality at 1 year, vessel patency, and any endoleaks, ruptures, reinterventions, and aneurysm exclusion at the end of follow-up.

RESULTS

A total of 39 studies (15 CS and 24 case reports), involving 429 patients, met the inclusion criteria. Overall, 436 lesions were treated, and 1521 aortic branches were covered by the multilayer stent. The mean follow-up for the 15 CS with 404 patients was 14.6 months. Compliance with the instructions for use was reported by eight CS, with 75% of the procedures performed within the instructions for use. However, 41% of the patients reported by 12 CS had undergone a previous aortic intervention. The pooled 30-day all-cause and 30-day aneurysm-related mortality rates were 0.56% (95% confidence interval [CI], 0.00%-2.54%) and 0.00% (95% CI, 0.00%-0.80%), respectively. The pooled aneurysm-related mortality at 1 year of follow-up was 5.25% (95% CI, 0.07%-14.91%). The pooled vessel patency at the end of follow-up was 99.12% (95% CI, 97.73%-99.93%). The pooled reintervention and endoleak rates at the end of follow-up were 10.94% (95% CI, 3.64%-20.67%) and 10.70% (95% CI, 4.45%-18.66%), respectively. The crude spinal cord ischemia and renal failure rates were 0.69% and 1.8%, respectively.

CONCLUSIONS

The results from the present review and meta-analysis have indicated the safety and efficacy of MFM stents for treating challenging aortic pathologic lesions when used as first-line treatment and within the instructions for use. The almost zero pooled 30-day all-cause and aneurysm-related mortality rates combined with the low crude spinal cord ischemia and renal failure rates indicate the use of MFM stents is a good treatment option for complex aortic lesions in the short- and mid-term periods. The lack of long-term follow-up warrants further research concerning the efficacy of the device in the long term.

Hemodynamics study of a multilayer stent for the treatment of aneurysms

Background

The changes of hemodynamics caused by the implantation of multilayer stent (MS) have significant effects for aneurysm sac.

Methods

Comparisons of 3D numerical models with/without a MS in an abdominal aortic aneurysm with a 90° branch vessel were numerically studied from the viewpoint of hemodynamics.

Results

The results showed that: (1) The flow fields and Wall Shear Stress (WSS) are changed dramatically after MS implantation. The velocity of the blood flow in aneurysm sac decreases significantly and the regions of low-WSS increase. These help thrombus formation; (2) The pressure in aneurysm slightly decreases and keeps close to the normal level of blood pressure, however the risk of aneurysm enlargement or even rupture still exists; (3) The flux and the velocity in branch artery are reduced by about half after MS implantation. Due to the implantation of MS, the changes in the flow field causes the decrease of pressure/WSS in aneurysm sac and the blood flow in branch vessel.

Conclusions

The implantation of MS into abdominal artery results in more low-WSS regions inside aneurysm which induces thrombus formation. The pressure is reduced slightly means the risk of aneurysm rupture exists.

Systematic Review and Patient-Level Meta-analysis of the Streamliner Multilayer Flow Modulator in the Management of Complex Thoracoabdominal Aortic Pathology

Purpose:

To examine the safety and short-term efficacy of the Streamliner Multilayer Flow Modulator (SMFM) in the management of patients with complex thoracoabdominal aortic pathology who are unfit for alternative interventions.

Methods:

Biomedical databases were systematically searched for articles published between 2008 and 2015 on the SMFM. A patient-level meta-analysis was used to evaluate aneurysm-related survival. Secondary outcomes were all-cause survival, stroke, spinal cord ischemia, renal impairment, and branch vessel patency. Other considerations were the impact of compliance with the instructions for use (IFU) on clinical outcome. Mean values and Kaplan-Meier estimates are presented with the 95% confidence interval (CI).

Results:

Fifteen articles (3 multicenter cohort studies, 3 observational cohort studies, and 9 case reports) were included, presenting 171 patients (mean age 68.8±12.3 years; 139 men). The mean aneurysm diameter was 6.7±1.6 cm (95% CI 6.4 to 6.9 cm). Technical success reported in 15 studies was 77.2%. Aneurysm-related survival at 1 year was 78.7% (95% CI 71.7% to 84.4%). One-year all-cause survival was 53.7% (95% CI 46.0% to 61.3%). There were no reported cases of spinal cord ischemia, renal insult, or stroke.

Conclusion:

The SMFM can be safely utilized in some patients with complex thoracoabdominal pathologies provided operators adhere to the IFU. The SMFM is a novel technology with no long-term published data on its sustained effectiveness and a lack of comparative studies. Randomized clinical trials, registries, and continued assessment are essential before this flow-modulating technology can be widely disseminated.

Endovascular repair of a juxtarenal saccular aneurysm using the Multilayer Flow Modulator: report of the first case performed in a Public Hospital in Brazil

Endovascular treatment of abdominal aortic aneurysms (AAA), involving the exits of the renal and visceral arteries still constitutes a considerable challenge. Many different techniques have been developed over the years in attempts to surmount the difficulties presented by these cases. Techniques that have gained prominence include fenestrated or branched stents, methods involving parallel prostheses, such as the chimney, periscope and sandwich techniques, and, more recently, flow modulation with Multilayer stents. We describe a case of a complex juxtarenal saccular AAA with a high surgical risk, both according to cardiological assessment and because the patient had a difficult airway caused by a total laryngectomy for early stage laryngeal neoplasm. In view of the technical simplicity of using Multilayer stents, the presence of chronic obstructive aortoiliac disease, ostial stenosis of the renal artery and a small diameter suprarenal aorta, options involving fenestrated/branched stents and techniques involving parallel prostheses were ruled out, because of the need for multiple accesses. In view of the dilemma it presented, we describe this case as a therapeutic challenge and present the treatment option employed, which has been successful over the short term.

Severe visceral ischemia and death after multilayer stent deployment for the treatment of a thoracoabdominal aortic aneurysm

The treatment of thoracoabdominal aortic aneurysms, both surgical and endovascular, has always been challenging. In the last years, the multilayer stent has emerged as an alternative device for the treatment of this condition. In this paper, we describe a catastrophic complication of the multilayer stent in a patient with thoracoabdominal aortic aneurysm, a case of massive visceral ischemia and death 3 months after stent deployment.