The Long-term Fate of Renal and Visceral Vessel Reconstruction After Open Thoracoabdominal Aortic Aneurysm Repair

Early Results of the Newly-Designed Flowdynamics Dense Mesh Stent for Residual Dissection After Proximal Repair of Stanford Type A or Type B Aortic Dissection: A Preliminary Single-Center Report From a Multicenter, Prospective, and Randomized Study

BACKGROUND

Negative remodeling of the distal aorta due to residual dissection significantly impacts the long-term outcomes of dissection patients after proximal repair of acute aortic dissection. Branched/fenestrated aortic stents are technically demanding, and studies of the first generation of multilayer flow modulators for tackling this clinical scenario are few and limited. The single-center results from a multicenter, prospective, and randomized controlled study aimed to verify the safety and effectiveness of a newly-designed flowdynamics dense mesh stent for treating residual dissection after proximal repair.

METHODS

Patients with nonchronic residual dissection involving visceral branches were prospectively enrolled in 3 centers (ChiCTR1900023638). Eligible patients were randomly assigned to the flowdynamics dense mesh stent (FDMS) group and control group. Follow-up visits were arranged at 1, 3, 6, and 12 months after recruitment. The primary endpoints were all-cause and aortic-related mortality. The secondary endpoints included visceral branch occlusion, reintervention, and severe adverse events. Morphological changes were analyzed to exhibit the therapeutic effect. Our center participated in the multicenter prospective randomized controlled trial, and the preliminary single-center experience was reported.

RESULTS

Thirty-six patients were enrolled in our center, and the baseline characteristics of the 2 groups were comparable. Thirty-four patients completed the 12 month follow-up. Freedom from all-cause and aortic-related death were 94.4% and 100%. All visceral branches remained patent in the FDMS group. Increased area of the true lumen (1.03±0.38 vs 0.48±0.63 cm2 at the plane below renal arteries, p=0.006; 1.27±0.80 vs 0.32±0.50 cm2 at the plane 5 cm below renal arteries, p<0.001) and decreased area of the false lumen at the plane below renal arteries (-1.03±0.84 vs -0.15±1.21 cm2, p=0.023) were observed in the FDMS group compared with those parameters in the control group. The FDMS group showed a significant increase in true lumen volume (p<0.001) and a significant decrease in false lumen volume (p=0.018).

CONCLUSIONS

This newly-designed FDMS for endovascular repair of residual dissection after the proximal repair is safe and effective at 12 months.

CLINICAL IMPACT

One-year results of the randomized controlled clinical trial indicated the short-term safety and promising effect of FDMS on treating non-chronic residual dissection after proximal repair. At the 12th-month follow-up, the true lumen expanded, the false lumen shrunk and all visceral arteries kept patent. As far as I'm concerned, this is the first randomized controlled study concerning utilizing multilayer flow mesh stent treating aortic dissection. Despite a preliminary single-center report, our results are supposed to provide high-quality evidence to guide clinical practice and fill the gap in the application of FDMS.

One-year results of the Flowdynamics Dense Mesh Stent for residual dissection after proximal repair of stanford type A or type B aortic dissection: a multicenter, prospective, and randomized study

OBJECTIVE

Negative remodeling of the distal aorta following proximal repair for acute aortic dissection has garnered growing attention. This clinical scenario has spurred the development of techniques and devices. A multicenter, prospective, and randomized controlled study was conducted with the aim of confirming the safety and effectiveness of a newly-designed flowdynamics dense mesh stent for the treatment of residual dissection after proximal repair.

METHODS

Patients with nonchronic residual dissection affecting visceral branches were prospectively enrolled at three centers and randomly allocated to either the FDMS group or the control group. Primary endpoints encompassed all-cause and aortic-related mortality, while the patency of branch arteries is indeed a key focal metric. Morphological changes (diameter, area, and volume) were analyzed to demonstrate the therapeutic effect.

RESULTS

One hundred twelve patients were recruited in the clinical trial, and 103 patients completed the 12-month follow-up. The rate of freedom from all-cause and aortic-related death in the FDMS group was 94.64 and 100%, respectively. All visceral branches remained patent. The FDMS group exhibited a substantial expansion in TL and a notable shrinkage in FL at the planes below renal arteries (ΔArea TL : FDMS vs. Control, 0.74±0.46 vs. 0.34±0.66 cm 2 , P <0.001; ΔArea FL : FDMS vs. Control, -0.72±1.26 vs. -0.12±0.86 cm, P =0.01) and 5 cm below renal arteries (ΔArea TL : FDMS vs. Control, 1.06±0.75 vs. 0.16±0.63 cm 2 , P <0.001; ΔArea FL : FDMS vs. Control, -0.53±1.43 vs. -0.25±1.00 cm, P =0.27). Meanwhile, the FDMS group demonstrated an increase of 22.55±11.14 cm 3 in TL ( P <0.001) and a corresponding reduction of 21.94±11.77 cm 3 in FL ( P =0.08).

CONCLUSIONS

This newly-designed FDMS for endovascular repair of residual dissection following the proximal repair is demonstrated to be safe and effective at 12 months.

Mid-term Renal and Mesenteric Artery Outcomes During Fenestrated and Branched Endovascular Aortic Repair for Complex Abdominal and Thoracoabdominal Aortic Aneurysms in the United States Aortic Research Consortium

OBJECTIVE

To report mid-term outcomes of renal-mesenteric target arteries (TAs) after fenestrated-branched endovascular aortic repair (FB-EVAR) of complex abdominal and thoracoabdominal aortic aneurysm.

BACKGROUND

TA instability (TAI) is the most frequent indication for reintervention after FB-EVAR.

METHODS

Data from consecutive patients enrolled in 9 prospective nonrandomized physician-sponsored investigational device exemption studies between 2005 and 2020 were reviewed. TA outcomes through 5 years of follow-up were analyzed for vessels incorporated by fenestrations or directional branches (DBs), including TA patency, endoleak, integrity failure, reintervention, and instability.

RESULTS

A total of 1681 patients had 6349 renal-mesenteric arteries were targeted using 3720 fenestrations (59%), 2435 DBs (38%), and 194 scallops (3%). Mean follow was 23 ± 21 months. At 5 years, TAs incorporated by fenestrations had higher primary (95 ± 1% vs 91 ± 1%, P < 0.001) and secondary patency (98 ± 1% vs 94 ± 1%, P < 0.001), and higher freedom from TAI (87 ± 2% vs 84 ± 2%, P = 0.002) compared with TAs incorporated by DBs, with no differences in other TA events. DBs targeted by balloon-expandable stent-grafts had significantly lower freedom from TAI (78 ± 4% vs 88 ± 1%, P = 0.006), TA endoleak (87 ± 3% vs 97 ± 1%, P < 0.001), and TA reintervention (83 ± 4% vs 95 ± 1%, P < 0.001) compared with those targeted by self-expandable stent-grafts.

CONCLUSIONS

Incorporation of renal and mesenteric TA during FB-EVAR is safe and durable with high 5-year patency rates and low freedom from TAI. DBs have lower patency rates and lower freedom from TAI than fenestrations, with better performance for self-expandable stent grafts as compared with balloon-expandable stent grafts.

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.