A novel physician-assembled endograft for the repair of pararenal, paravisceral, Crawford type IV thoracoabdominal aortic aneurysms, and aneurysms requiring treatment after prior repair

Thoracoabdominal aneurysm repair using the Unitary Manifold Device

OBJECTIVE

To present a single-center prospective study of 126 consecutively treated patients who underwent endovascular repair of a thoracoabdominal aortic aneurysm with the physician-modified, nonanatomic-based Unitary Manifold (UM) device.

METHODS

Data were collected from 126 consecutive all-comer patients treated with the physician-modified, nonanatomic-based UM from 2015 to 2023. Treatment was performed at a single center by a single physician under a Physician Sponsored Investigation Exemption G140207.

RESULTS

The UM was indicated for repair of all Crawford extents including juxtarenal, pararenal, and short-neck infrarenal aneurysms (<10 mm) in 126 consecutive patients. Patients were not excluded from the study based on presentation, extent of aneurysm or dissection, or history of a spinal cord event. Patients with a thoracoabdominal aortic aneurysm were categorized by Crawford classification: types I and V (3.3%, n = 4), type II (3.3%, n = 4), type III (1%, n = 1), and type IV (93.3%, n = 117). The type IV classification patients were further categorized with 33 (28.2%) true type IV, 68 (58.1%) pararenal or infrarenal, and 16 (13.7%) with dissection. Technical success was 99.2% (n = 125). The most common major adverse event within both 30 days and 365 days of all patients was respiratory failure (11.9%, n = 15, and 13.5%, n = 17, respectively). One patient (0.8%) experienced persistent paraplegia at 365 days. Reintervention for patients at 365 days was 5.6% (n = 7). Of the 444 branches stented, the primary patency rate was remarkably high as only three patients (2.4%) required reintervention due to loss of limb patency within 365 days. Aneurysm enlargement (≥5 mm) occurred in 1.6% (n = 2) patients, and no patients experienced aneurysm rupture. No patients underwent conversion to open repair. The aneurysm-related mortality at 365 days for all patients was 4.0% (n = 5), whereas all-cause mortality was 16.7% (n = 21). Physician-modified endograft device integrity failure was not observed in any patient.

CONCLUSIONS

The UM device demonstrated remarkable technical surgical success, treatment success, and device patency rates with very reasonable major adverse events and reintervention rates. This study is the most representative example of the general population in comparison with other studies of off-the-shelf devices, with 126 consecutive all-comer patients with diverse pathologies.

Single-Site Review of Spinal Cord Protection Protocols Including the Utilization of Spinal Drains versus Medical Management with Branched Endovascular Aortic Repair

BACKGROUND

Spinal cord ischemia (SCI) continues to be a devastating complication after repair of thoracoabdominal aortic aneurysms. The objective of this review is to present our single-center outcomes after the implementation of a standardized neuroprotective protocol following branched endovascular aortic repair.

METHODS

A standardized neuroprotective protocol including preoperative steroids, acetazolamide, intraoperative hemodynamic parameters, and postoperative treatment goals was initiated in November 2019. Physician-modified branched endovascular repairs were completed at a single center from 2012 to 2021 with outcomes reviewed both before (n = 107) and after (n = 67) the implementation of the neuroprotective protocol. The primary end point was the incidence of any SCI event at 30 days. Secondary end points included all-cause mortality, stroke, myocardial infarction, and renal failure at 30 days. Patients with Crawford extents I-III, renal failure, or necessitating emergent repair were deemed high risk for SCI events and underwent a subset analysis. Survivability after SCI was estimated using Kaplan-Meier tables.

RESULTS

Of the 174 consecutive patients treated, the 67 patients treated following implementation of the neuroprotective protocol were more likely to have experienced a prior myocardial infarction (26.9% vs. 14%; P = 0.0466) and have a history of chronic obstructive pulmonary disease (64.3% vs. 45.8%; P = 0.02). This group was more likely to be treated for paravisceral aneurysms (53.7% vs. 24.3%; P = 0.0002). Postprotocol implementation, spinal drain use was lower (6% vs. 38.3%; P = <0.0001) with 100% of these drains placed in urgent or unstaged thoracoabdominal aortic aneurysm repairs as a part of the protocol. Rates of any SCI event among all patients before and after implementation of the protocol were 9.3% (n = 10 of 107) and 6% (n = 4 of 67; P = 0.57), respectively. In comparison, the protocol significantly reduced SCI rates to 0 (0% vs. 17.1%; P = 0.0407) in high-risk patients. Frequency of renal failure was reduced (3% vs. 14%; P = 0.018) after initiation of the protocol. Patients in the postprotocol group had significantly improved 1-year mortality rate (9% vs. 27.1%; P = 0.0035) and renal failure rates (2% vs. 15%; P = 0.018). Regression models indicated that patients in the postprotocol group had lower likelihood of mortality and renal failure than patients in preprotocol group (P < 0.05) and that spinal drain reduced mortality (P < 0.1).

CONCLUSIONS

Implementation of a standardized neuroprotective protocol that focuses on medical management and fluid dynamics may significantly reduce risk of SCI after branched endovascular repairs, with the most significant improvement of SCI outcomes involving those at greatest risk for developing SCI. Also noteworthy, there was significant improvement to 1-year survivability after the implementation of this neuroprotective protocol.

Aneurysm extent-based mortality differences in complex endovascular repair of thoracoabdominal aneurysms in the Vascular Quality Initiative and the United States Aortic Research Consortium

BACKGROUND

Endovascular management of thoracoabdominal aneurysms (TAAA) is becoming more common. Technological advances including custom devices under the Physician-Sponsored Investigational Device Exemption (PS-IDE), physician-modified endografts (PMEG), and parallel stenting techniques have expanded the extent of disease that is amenable to endovascular treatment. Patients within the PS-IDE studies are a highly selected group of patients, whereas patients treated with PMEG as captured within the Society for Vascular Surgery Vascular Quality Initiative (SVS VQI) represent a real-world experience. Research within both the SVS VQI on PMEG and the US Aortic Research Consortium (US-ARC) has demonstrated a relationship between extent of aneurysmal disease and mortality after complex endovascular TAAA repair, but no direct comparison of these cohorts has been conducted. In this study, we sought to compare outcomes of custom PS-IDE devices with off-label uses of commercially available devices for the endovascular management of TAAAs.

METHODS

A retrospective review of patients presenting for elective endovascular TAAA repair for asymptomatic disease between 2011 and 2019 was conducted within both the SVS VQI registry and the US-ARC. Patients within the SVS VQI registry were treated with either PMEG or with parallel stenting techniques. Patients within the US-ARC were treated with PS-IDE custom devices. The extent of aneurysm disease was defined by the deployment zones documented for the devices entered in the registry using Crawford extents I to V. Primary outcomes were 30-day and 1-year mortality rates.

RESULTS

A total of 3212 patients were included in the study: 1571 PMEG/parallel stenting within the VQI registry and 1641 with PS-IDE within the US-ARC database. The majority of patients presented with extent IV aneurysms (n = 1827 [57%]), with extent IV aneurysms being slightly more prevalent within the US-ARC cohort. Maximal aneurysm diameter within each extent did not vary between the US-ARC and VQI cohorts. Across all patients, the 30-day mortality was 4.4% and the 1-year mortality was 12.2%. Unadjusted mortality at 30-days was 6.7% within the VQI, and 2.2% in the US-ARC (P < .001). The unadjusted 1-year mortality was 14.3% within the VQI and 10.2% within the US-ARC (P < .001). When adjusted for aneurysm extent, similar differences in 30-day and 1-year survivals were identified.

CONCLUSIONS

Patients treated in PS-IDE studies had better 30-day and 1-year survival rates compared with those treated with a similar extent of disease using off-label approaches in a real-world registry. These differences are complex and likely associated with a number of factors, including arterial anatomy, patient comorbidities, device construct, and volume outcomes, as well as complex and unmeasurable surgeon- and patient-specific factors.

Treatment of a type Ia endoleak following EVAR using a custom-made inner branch device

OBJECTIVES

We represent two cases of late proximal type I endoleak following EVAR with aneurysm expansion that were treated with a custom-made graft with inner branches.

METHODS

Two patients of 87 and 82 years old were operated by EVAR 6 and 8 years ago for abdominal aortic aneurysm. Both had proximal type I endoleak with aneurysm sac expansion. Open surgery had a high risk, and a proximal aortic extension with a simple aortic cuff was not possible neither because previous EVAR grafts were already at the level of the renal arteries. A custom-made endograft with inner branches was planned as a fenestrated graft was not technically possible.

RESULTS

We successfully treated both patients using a custom-made graft with four inner branches from Jotec (Cryolife, Kennesaw, GA). Three months' follow-up CT scan did not show any endoleaks. All target vessels were patent with good conformability of the bridging stents.

CONCLUSION

The treatment of proximal type I endoleak using inner branches' endografts is feasible. This novel technology might broaden the indications for complex aortic repair in a group of patients where fenestrated endografts are not possible.

Treatment of thoracoabdominal aortic aneurysmal degeneration following aortic dissections at a single surgical center using a physician-assembled branched endovascular stent graft

OBJECTIVE

Aneurysmal degeneration of aortic dissection portends significant morbidity and mortality consequences in the subacute and chronic phases of aortic dissection. This paper describes the use of a multi-branched stent graft system for the treatment of thoracoabdominal aneurysmal degeneration of dissections with visceral segment involvement and reports upon the 30-day and one-year outcomes for the first 18 patients treated with this design configuration.

METHODS

The in-hospital, 30-day and one-year morbidity and mortality outcomes of 18 consecutive patients treated with the physician-assembled visceral manifold or unitary manifold stent graft systems between 2013 and 2022 were evaluated.

RESULTS

A total of 18 patients were treated for aneurysmal changes after aortic dissection. A total of 71 visceral vessels were successfully stented. There were no acute procedural failures. There were no episodes of paraplegia, reinterventions for type I or III endoleaks, patency-related events or mortalities reported in the first 30 days following treatment. One-year, all-cause mortality demonstrated 2/11 (18.2%).

CONCLUSIONS

Aneurysmal degeneration of aortic dissection poses significant risks to patients with medically managed aortic dissections and those under surveillance. When these aneurysms develop in the thoracoabdominal region, treatment becomes even more challenging given the problem of visceral vessel patency, as these vessels can originate off the true or false lumens. The physician-designed endovascular stent graft system reported upon here has been successfully deployed in 18 patients with no acute procedural failures and promising clinical results. This treatment modality may offer utility to vascular surgeons whose patients with thoracoabdominal aneurysmal degeneration following aortic dissection have historically had limited endovascular repair prospects.

Temporary Reperfusion of the Aneurysm Sac as a Prevention of Spinal Cord Ischemia After Endovascular Treatment of Thoracoabdominal Aortic Aneurysm: Systematic Review and Meta-analysis

BACKGROUND

Spinal cord ischemia (SCI) is still a feared complication for patients suffering from thoracoabdominal aortic aneurysm (TAAA) who undergo endovascular treatment. The aims of this work are to review the available literature on different reperfusion methods of the aneurysm sac, and to analyze whether the different reperfusion methods, also in combination with other factors, are effective in reducing SCI risk and if the impact varies with the patient's age.

METHODS

PubMed/MEDLINE library was searched for studies published until November 2020 concerning TAAA, endovascular repair, and SCI preventive measures. Systematic review and meta-analysis were conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses criteria. Primary outcome consisted of correlation between endovascular repair techniques (type A: single step; type B: staged approach with reperfusion branches; type C: staged sequential approach with positioning of the thoracic component). A logistic-weighted regression for each event (SCI, transient, and permanent) was then performed with type of treatment, age, and interaction between them as input factors. Finally, another logistic-weighted regression was performed to analyze the other relevant factors for which observations are available together with the endovascular technique.

RESULTS

Data from 53 studies with a total of 3095 patients were analyzed. Type A, type B, and type C endovascular strategies were adopted in 75%, 13%, and 12% of studied patients, respectively. Data showed that both type B and type C treatments are associated with lower risk of SCI, with a higher reduction of type C with respect to type B, although this positive trend is limited for elder patients. Moreover, a greater aortic diameter, a reduced aneurysm extent, and the absence of cerebrospinal fluid drainage positioning contribute to lower the risk of SCI. Concerning permanent SCI, both type B and type C are effective in reducing percentages for all ages, with type C treatment more beneficial for younger patients and type B for elder ones.

CONCLUSION

According to the anatomy and the endovascular repair feasibility criteria, staged endovascular treatment appears to offer relevant advantages over single-step treatment in reducing the risk of SCI, regardless of the reperfusion method adopted.

Endovascular treatment of thoracoabdominal aortic aneurysms

Endovascular repair of thoracoabdominal aneurysms using fenestrated and/or branched stent grafts is technically feasible and efficacious but carries a steep learning curve. This innovative surgical approach is associated with less perioperative morbidity than traditional open repair and its early and mid-term outcomes are very favorable. Spinal cord ischemia remains a devastating complication after these procedures, hence the importance of various neuroprotective strategies. Widespread applicability remains limited in the United States, as no custom-made or off-the-shelf endografts are commercially available. Access to these devices remains limited to physician-sponsored or industry-sponsored clinical trials, but results from the Cook p-Branch and Gore Thoracoabdominal Branch Endoprosthesis trials are on the horizon.

Incidence of Acute and Chronic Renal Failure Following Branched Endovascular Repair of Complex Aortic Aneurysms

BACKGROUND

The purpose of this study was to examine the incidence of acute kidney injury and chronic renal impairment following branched endovascular aneurysm repair (BEVAR) of complex thoracoabdominal aortic aneurysms (TAAA) using the Medtronic Valiant Thoracoabdominal Aortic Aneurysm stent graft system (MVM), the physician-modified Visceral Manifold, and Unitary Manifold stent graft systems. The objective was to report the acute and chronic renal function changes in patients following complex TAAA aneurysm repair.

METHODS

This is an analysis of 139 patients undergoing branched endovascular repair for complex TAAAs between 2012 and 2020. Patient renal function was evaluated using serum creatinine and estimated glomerular filtration rate at baseline, 48 hr, discharge, 1 month, 6 months, and annually to 2 years. Patients on dialysis prior to the procedure were excluded from data analysis.

RESULTS

A total of 139 patients (mean age 71.13; 64.7% male) treated for TAAA with BEVAR met inclusion criteria and were evaluated. A total of 530 visceral vessels were stented. A majority of patients (n = 131, 94.2%) underwent a single procedure while 8 required staged procedures. Thirty-day, 1-year and 2-year all-cause mortality rates were 5.8%, 25.2%, and 32.4%, respectively. Primary and secondary patency rates at a median follow-up of 26.9 months (95% CI; 21.1 - 32.7) were 96.2% and 97.5% for all vessels and 95.4% and 96.9% for renal arteries, respectively. Postoperative acute kidney injury (AKI) was identified in 22 (15.8%) patients. At discharge, 16 patients (11.6%) had an increase in CKD stage with 3 requiring permanent dialysis. Five additional patients required permanent dialysis over the 2-year follow-up period for a total of 8 (5.8%). Increasing age (HR = 1.0327, P= 0.0477), hemoglobin < 7 prior to procedure (HR = 2.4812, P= 0.0093), increasing maximum aortic diameter (HR = 1.0189, P= 0.0084), presence of AKI (HR = 2.0757, P= 0.0182), and increase in CKD stage (HR = 1.3520, P= 0.002) at discharge were significantly associated with decreased patient survival.

CONCLUSIONS

Postoperative AKI and a chronic decline in renal function continue to be problematic in endovascular repair of complex aortic aneurysms. This study found that BEVAR using the manifold configuration resulted in immediate and mid-term renal function that is comparable to similar analyses of branched and/or fenestrated grafts.

Combination of mural thrombus and age improves the identification of all-cause mortality following branched endovascular repair

BACKGROUND

In-hospital and 30-day mortality rates of endovascular repair of thoracoabdominal aortic aneurysms shows a significant improvement over open surgery, although we are not seeing a significant difference at 1 year. We assess the hypothesis that a greater mural thrombus ratio within the aorta could function as an indicator of postoperative mortality.

METHODS

The mural thrombus ratio and preoperative comorbidities of 100 consecutive patients from a single center undergoing endo-debranching between 2012 and 2019 were evaluated. Logistic regression, survival analysis, and decision tree methods were used to examine each variable's association with death at 1 year.

RESULTS

At the time of analysis, 73 subjects had 1-year outcomes and adequate imaging to assess the parameters. At 1 year, the overall survival for all subjects was 71.2% (21 died, 52 survived). For patients with a favorable mural thrombus ratio (n = 36), the overall 1-year survival was 86.1% (5 died, 31 survived). The subjects with an unfavorable mural thrombus ratio (n = 37), had an overall 1 year survival of 56.8% (16 died, and 21 survived). The only preoperative mortality factor that was statistically significant between the subjects with an unfavorable mural thrombus ratio was age of the patient. The survival for subjects 75 years and older with an unfavorable mural thrombus ratio was 90% (one died, nine survived) vs only 44.4% survival for subjects less than 75 years with an unfavorable mural thrombus ratio (15 died, 12 survived).

CONCLUSIONS

This study examined whether a patient's mural thrombus ratio may be an indicator of 1-year survival. These findings suggest that the combination of a patient's aortic mural thrombus ratio and age can function as a preoperative indicator of their underlying cardiac reserve. Identifying patients with low cardiac reserve and fitness to handle the increased cardiac demands owing to the physiologic response to extensive aortic stent grafting before undergoing aortic repair may allow for modification of preoperative patient counseling and postoperative care guidelines to better treat this patient population.