The use of aortic balloon occlusion in traumatic shock: first report from the ABO trauma registry

PURPOSE

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a technique for temporary stabilization of patients with non-compressible torso hemorrhage. This technique has been increasingly used worldwide during the past decade. Despite the good outcomes of translational studies, clinical studies are divided. The aim of this multicenter-international study was to capture REBOA-specific data and outcomes.

METHODS

REBOA practicing centers were invited to join this online register, which was established in September 2014. REBOA cases were reported, both retrospective and prospective. Demographics, injury patterns, hemodynamic variables, REBOA-specific data, complications and 30-days mortality were reported.

RESULTS

Ninety-six cases from 6 different countries were reported between 2011 and 2016. Mean age was 52 ± 22 years and 88% of the cases were blunt trauma with a median injury severity score (ISS) of 41 (IQR 29-50). In the majority of the cases, Zone I REBOA was used. Median systolic blood pressure before balloon inflation was 60 mmHg (IQR 40-80), which increased to 100 mmHg (IQR 80-128) after inflation. Continuous occlusion was applied in 52% of the patients, and 48% received non-continuous occlusion. Occlusion time longer than 60 min was reported as 38 and 14% in the non-continuous and continuous groups, respectively. Complications, such as extremity compartment syndrome (n = 3), were only noted in the continuous occlusion group. The 30-day mortality for non-continuous REBOA was 48%, and 64% for continuous occlusion.

CONCLUSIONS

This observational multicenter study presents results regarding continuous and non-continuous REBOA with favorable outcomes. However, further prospective studies are needed to be able to draw conclusions on morbidity and mortality.

Randomized clinical trial of mast cell inhibition in patients with a medium-sized abdominal aortic aneurysm

Background

Abdominal aortic aneurysm (AAA) is thought to develop as a result of inflammatory processes in the aortic wall. In particular, mast cells are believed to play a central role. The AORTA trial was undertaken to investigate whether the mast cell inhibitor, pemirolast, could retard the growth of medium-sized AAAs. In preclinical and clinical trials, pemirolast has been shown to inhibit antigen-induced allergic reactions.

Methods

Inclusion criteria for the trial were patients with an AAA of 39–49 mm in diameter on ultrasound imaging. Among exclusion criteria were previous aortic surgery, diabetes mellitus, and severe concomitant disease with a life expectancy of less than 2 years. Included patients were treated with 10, 25 or 40 mg pemirolast, or matching placebo for 52 weeks. The primary endpoint was change in aortic diameter as measured from leading edge adventitia at the anterior wall to leading edge adventitia at the posterior wall in systole. All ultrasound scans were read in a central imaging laboratory.

Results

Some 326 patients (mean age 70·8 years; 88·0 per cent men) were included in the trial. The overall mean growth rate was 2·42 mm during the 12-month study. There was no statistically significant difference in growth between patients receiving placebo and those in the three dose groups of pemirolast. Similarly, there were no differences in adverse events.

Conclusion

Treatment with pemirolast did not retard the growth of medium-sized AAAs. Registration number: NCT01354184 (https://www.clinicaltrials.gov).

Endovascular repair of acute uncomplicated aortic type B dissection promotes aortic remodelling: 1 year results of the ADSORB trial

OBJECTIVES

Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year.

METHODS

The AD history had to be less than 14 days, and exclusion criteria were rupture, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB.

RESULTS

Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17% of the cases. During the first 30 days, no deaths occurred in either group, but there were three crossovers from the BMT to the BMT+TAG group, all due to progression of disease within 1 week. There were two withdrawals from the BMT+TAG group. At the 1-year follow up there had been another two failures in the BMT group: one malperfusion and one aneurysm formation (p = .056 for all). One death occurred in the BMT+TAG group. For the overall endpoint BMT+TAG was significantly different from BMT only (p < .001). Incomplete false lumen thrombosis, was found in 13 (43%) of the TAG+BMT group and 30 (97%) of the BMT group (p < .001). The false lumen reduced in size in the BMT+TAG group (p < .001) whereas in the BMT group it increased. The true lumen increased in the BMT+TAG (p < .001) whereas in the BMT group it remained unchanged. The overall transverse diameter was the same at the beginning and after 1 year in the BMT group (42.1 mm), but in the BMT+TAG it decreased (38.8 mm; p = .062).

CONCLUSIONS

Uncomplicated AD can be safely treated with the Gore TAG device. Remodelling with thrombosis of the false lumen and reduction of its diameter is induced by the stent graft, but long term results are needed.

One hundred percent of ruptured aortic abdominal aneurysms can be treated endovascularly if adjunct techniques are used such as chimneys, periscopes and embolization

Observational studies comparing endovascular aneurysm repair (EVAR) with open repair (OR) in ruptured abdominal aortic aneurysms (AAA) have suggested a benefit for EVAR but have been questioned recently by randomized controlled trials (RCT). A low eligibility for endovascular repair is a main limitation of these RCTs. In contrast, data from 473 patients from 1998 to 2011 in the Örebro/Zurich series show that nearly all AAA patients presenting with rupture can in fact be treated with EVAR with a low 30-day mortality rate (24%) and a minimal exclusion rate (4%). By using different adjunct techniques, such as chimneys and periscopes, also juxtarenal aneurysms can be treated even if simultaneous aortic balloon occlusion is necessary. OnyxTM embolization of the internal iliac artery in patients with aortoiliac aneurysms prevents back flow, thus avoiding an endoleak type. From May 2009 until December 2013, 70 patients arrived at Örebro University Hospital with a ruptured AAA diagnose. Nine percent were considered unfit for any intervention (including OR) and were treated medically. All of the 64 patients that underwent surgery were treated with EVAR and 30-day mortality in this group was 17 of 64 patients (27%). The mortality for patients treated with adjunct techniques was not significantly increased compared with patients treated with standard EVAR. In conclusion, our data support that open repair of ruptured AAA can be replaced by EVAR with appropriate management of existing adjunct techniques.

Type II endoleak: a problem to be solved

Type II endoleak is a common phenomenon after endovascular aortic aneurysm repair (EVAR). The majority of type II endoleaks are considered benign, since approximately one third of them resolve spontaneously and they have no influence on mortality and rupture rate after EVAR. Thus, type II endoleak without sac expansion is recommended to be observed conservatively. Treatment for type II endoleak with sac expansion is still controversial. It has been reported that a certain type II endoleak causes sac expansion and late aneurysm rupture. Type II endoleak is often treated with solid agents as coils and vascular plugs or with liquid agents as different glues and thrombin. Onyx™ is a relatively new liquid embolic agents and it seems promising due to its capability to be injected in controlled manner with good visualization. Perisac embolization is another novel technique and it deals with all patent arterial branches, yet it requires further long-term studies. There are several access routes in treatment for type II endoleak. Translumbar approach seems more successful and safe than transarterial approach, and transcaval approach reduces the risk for infection compared to translumbar embolization. However, success rate of intervention for type II endoleak is unsatisfactory and recurrence rate is high. Endovascular treatment for type II endoleak is dependent on its nature and sometimes it can be challenging. Therefore, treatment for type II endoleak, including preventive embolization should be considered carefully and development of embolization methods is essential.

Early outcome of endovascular aneurysm repair in challenging aortic neck morphology based on experience from the GREAT C3 registry

AIM

The aim of this paper was to evaluate early outcome of the GORE® EXCLUDER® AAA Endoprosthesis featuring C3 Delivery System in subjects with aortic neck anatomy outside IFU.

METHODS

Individual patient data prospectively collected over a 2 year period from the Global Registry for Endovascular Aortic Treatment (GREAT). For each subject a minimum data set was collected containing demographic, pre/intra- and postoperative variables. Main outcome measures were successful exclusion of the AAA and occurrence of any major endoleak at 1 month. In this study, outside IFU was defined as aortic neck length less than 15 mm and/or aortic neck angle greater than 60 degrees.

RESULTS

A total of 400 subjects, (86.6% male, mean age 73.9 years). Primary pathology was AAA in 94.2% with 98.2% undergoing EVAR as a primary procedure. Sixty-eight subjects underwent EVAR outside IFU (neck length <15 mm N.=32, neck angle >60˙N.=47 and neck length <15 mm and angle >60° N.=11). The graft was successfully deployed within 5 mm of its intended location in 63 (94%) cases utilising a total of 33 repositioning episodes. Eight aortic cuffs were used, 5 to treat a type 1 endoleak. At 30 days we recorded 2 type 2 endoleaks both successfully treated and 1 type 1b also successfully treated. There were 2 deaths, one in each group.

CONCLUSION

GORE® EXCLUDER® AAA Endoprosthesis featuring C3 Delivery System allows re-positioning to be performed safely in cases outside IFU. Repositioning is an effective operative manoeuvre and facilitates EVAR in challenging anatomy. Longer follow-up is required to evaluate the durability of these results at 30 days.

Intra-peritoneal microdialysis and intra-abdominal pressure after endovascular repair of ruptured aortic aneurysms

OBJECTIVES

This study aims to evaluate intra-peritoneal (ip) microdialysis after endovascular aortic repair (EVAR) of ruptured abdominal aortic aneurysm (rAAA) in patients developing intra-abdominal hypertension (IAH), requiring abdominal decompression.

DESIGN

Prospective study.

MATERIAL AND METHODS

A total of 16 patients with rAAA treated with an emergency EVAR were followed up hourly for intra-abdominal pressure (IAP), urine production and ip lactate, pyruvate, glycerol and glucose by microdialysis, analysed only at the end of the study. Abdominal decompression was performed on clinical criteria, and decompressed (D) and non-decompressed (ND) patients were compared.

RESULTS

The ip lactate/pyruvate (l/p) ratio was higher in the D group than in the ND group during the first five postoperative hours (mean 20 vs. 12), p = 0.005 and at 1 h prior to decompression compared to the fifth hour in the ND group (24 vs. 13), p = 0.016. Glycerol levels were higher in the D group during the first postoperative hours (mean 274.6 vs. 121.7 μM), p = 0.022. The IAP was higher only at 1 h prior to decompression in the D group compared to the ND group at the fifth hour (mean 19 vs. 14 mmHg).

CONCLUSIONS

Ip l/p ratio and glycerol levels are elevated immediately postoperatively in patients developing IAH leading to organ failure and subsequent abdominal decompression.

Adverse events during treatment of critical limb ischemia with autologous peripheral blood mononuclear cell implant

AIM

Trials have reported clinical improvement and reduced need for amputation in critical limb ischemia (CLI) patients receiving therapeutic angiogenesis with stem cells. Our objective was to test peripheral stem cell therapy efficacy and safety to gain experiences for further work.

METHODS

We included nine CLI patients (mean age 76.7 ±9.7). Stem cells were mobilized to the peripheral blood by administration of G-CSF (Filgrastim) for 4 days, and were collected on day five, when 30 mL of a stem cell suspension was injected into 40 points of the limb. The clinical efficacy was evaluated by assessing pain relief, wound healing and changes in ankle-brachial pressure index (ABI). Local metabolic and inflammatory changes were measured with microdialysis, growth factors and cytokine level determination. Patients were followed for 24 weeks.

RESULTS

Four patients experienced some degree of improvement with pain relief and/or improved wound healing and ABI increase. One patient was lost to follow up due to chronic psychiatric illness; one was amputated after two weeks. Two patients had a myocardial infarction (MI), one died. One patient died from a massive mesenteric thrombosis after two weeks and one died from heart failure at week 11. Improved patients showed variable effects in cytokine-, growth factor- and local metabolic response.

CONCLUSION

Even with some improvement in four patients, severe complications in four out of nine patients, and two in relation to the bone marrow stimulation, made us terminate the study prematurely. We conclude that with the increased risk and the reduced potential of the treatment, peripheral blood stem cell treatment in the older age group is less appropriate. Metabolic and inflammatory response may be of value to gain insight into mechanisms and possibly to evaluate effects of therapeutic angiogenesis.

From puncture to closure of the common femoral artery in endovascular aortic repair

In all fields of surgery there is a trend towards less invasive procedures reducing hospital stay, complications and mortality. Open surgery in the treatment of aortic diseases is gradually less applied, and instead endovascular aortic repair - EVAR - is a widely accepted treatment modality of today. The traditional approach in EVAR involves surgical exposure of the femoral arteries with bilateral groin incisions. Through the groin access, and under fluoroscopy, a special insertion sheath introducer is used to position a stent graft in the desired location with the patient in general or epidural anesthesia. The evolving stent-technology with smaller sheath sizes has broadened the scenario for alternative approaches for access and closure of the common femoral arteries. The following review presents an introduction on technical aspects of puncture of the femoral artery and closure of the arterial wall using percutaneous closure devices. We also aim to discuss three important approaches to expose and close the femoral arteries during endovascular aortic repair: The cut down approach, the true percutaneous technique, and the femoral fascial closure. Finally, factors important in the choice of techniques will be discussed in relation to early and late complications. We suggest that a percutaneous femoral approach should initially be considered for all endovascular aortic procedures, but with a low threshold to convert to traditional cut-down technique when complications such as bleeding, stenosis, ischemia, or femoral artery injury occur. The choice of the optimal femoral approach depends on the unique anatomy of each patient.

Top-fenestrating technique in stentgrafting of aortic diseases with mid-term follow-up

AIM

As a consequence of the rapid growth of thoracic and abdominal endovascular aneurysm repair management of aortic branches has come into focus. The top-fenestrating technique can be used where one or two of the renal arteries, the left carotid artery or the left subclavian artery, have deliberately been covered by a stent-graft and immediately reopened by a preplaced stent. The aim of this study is to evaluate whether this technique is feasible and durable.

METHODS

Registry study on 24 patients endovascular repaired with the top-fenestrating technique between September 2004 and January 2008. Elective operations were performed in 15 patients and acute procedures in nine. The median neck length for the patients having a carotid stent was 0 mm, range -18-15, related to the left subclavian artery and median 11 mm, range 0-31 mm, for those having a renal stent. Altogether 25 stents were used.

RESULTS

There were two postoperative deaths. One patient died from a cardiac infarction and the other, a ruptured thoracic aortic aneurysm, had a major stroke. Median follow-up time was 17 months (range 1-40 months). Two patients died during follow-up from no-aneurysm related reasons. One type I endoleak was solved with a secondary intervention. Two patients had type II endoleak, which was not treated. After 12 months, 71% of the aneurysms had significantly decreased in size. None of the aneurysms had increased. There were no stent-graft migrations in the entire group. None of the stented branches was lost during follow-up.

CONCLUSION

The top-fenestrating technique is feasible in short aortic necks and results are durable in a mid-term follow-up perspective.

Endovascular Repair of the Ruptured Abdominal Aortic Aneurysm

The present knowledge on endovascular repair of ruptured abdominal aortic aneurysms (rAAA) prevents firm conclusions when to use this method in comparison to open repair. This review article briefly summarizes results from case series, and discusses how to achieve reliable information despite the absence of randomized controlled trials. At present a careful conclusion might be that dedicated centers with an adequate organization and reasonably high volume of abdominal aortic aneurysm (AAA) should use detailed registry protocols to achieve experience and data to create an as reliable basis as possible for future recommendations.

Remodeling of the thoracic aorta after stent grafting of type B dissection: a Swedish multicenter study

AIM

Endovascular repair of complicated type B dissections has evolved as a promising alternative to open repair. Previous studies have indicated that continued false lumen flow is a predictor of continued aortic dilatation and risk of rupture during follow-up. This multicenter study was conducted to analyze the postoperative changes of the false lumen after endografting of complicated type B dissections.

METHODS

All patients treated with endovascular stent grafts for thoracic type B dissections at 5 major Vascular Centers in Sweden were identified through local databases. Review of charts and all available pre- and postoperative CT scans were performed to identify demographics, indications for repair as well as postoperative changes of the aorta and false lumen.

RESULTS

A total of 129 patients treated for type B dissections between 1994 and December 2005 were identified. Median radiological follow-up was 14 months. Fourteen patients died perioperatively leaving 115 patients available for analysis. Seventy-four of these had CT imaging of sufficient quality for morphological analysis. The vast majority of acute patients were treated for rupture or end-organ ischemia whereas most chronic patients were treated for asymptomatic aneurysms. In 80% of patients, the false lumen thrombosed along the stent graft but it remained perfused distal to the stent graft fixation in 50% of patients. Only 5% of patients presented with aortic enlargement of the stent grafted area when adequate proximal sealing was achieved. The distal, uncovered aorta displayed expansion in 16% of patients.

CONCLUSIONS

The stent grafted thoracic aorta after type B dissection appears to be stabilized by covering the primary entry site with a stent graft in the majority of both acute and chronic dissections. The uncovered portion of the aorta distal to the stent graft, however, remains at risk of continuous dilatation. Stent grafting for complicated type B thoracic dissections seems to be a treatment option with reasonable morbidity and mortality even though the incidence of severe complications is still significant.

Radiation exposure in stent-grafting of abdominal aortic aneurysms

In recent years, endovascular stent-grafting of abdominal aortic aneurysms has become more and more common. The radiation dose associated with these procedures is not well documented however. The aim of the present study was to estimate the radiation exposure and to simulate the effects of a switch from C-arm radiographic equipment to a dedicated angiographic suite. Dose-area product (DAP) was recorded for 24 aortic stent-grafting procedures. Based on these data, entrance surface dose (ESD) and effective dose were calculated. A simulation of doses at various settings was also performed using a humanoid Alderson phantom. The image quality was evaluated with a CDRAD contrast-detail phantom. The mean DAP was 72.3 Gy cm(2) at 28 min fluoroscopy time with a mean ESD of 0.39 Gy and a mean effective dose of 10.5 mSv. If the procedures had been performed in an angiographic suite, all dose values would be much higher with a mean ESD of 2.9 Gy with 16 patients exceeding 2 Gy, which is considered to be a threshold for possible skin injury. The image quality for fluoroscopy was superior for the C-arm whilst the angiographic unit gave better acquisition images. Using a C-arm unit resulted in doses similar to percutaneous coronary intervention (PCI). If the same patients had been treated using dedicated angiographic equipment, the risk of skin injury would be much higher. It is thus important to be aware of the dose output of the equipment that is used.

Experiences of Intentional Carotid Stenting in Endovascular Repair of Aortic Arch Aneurysms—Two Case Reports

Endovascular repair of thoracic aneurysms has emerged as an attractive alternative especially in patients at high risk. However, the left common carotid artery limits the use of stent-grafts in aneurysms located in the aortic arch or close to the left subclavian artery. We report two cases with aneurysms in the distal arch and proximal descending aorta, where we have used a carotid stent in juxtaposition to an aortic stent-graft, to gain a longer proximal neck in the aortic arch in an attempt not to rely only on a by-pass graft feeding the left carotid artery.