Multicenter experience in translumbar type II endoleak treatment in the hybrid room with needle trajectory planning and fusion guidance

OBJECTIVE

The objective of this study was to evaluate the efficacy of treating type II endoleaks (T2Ls) after aortic endovascular repair with image guidance translumbar puncture using intraoperative cone beam computed tomography with preprocedure computed tomography angiography fusion in hybrid operating rooms.

METHODS

Twenty-six consecutive T2L patients in three different institutions were treated between March 2015 and September 2017 by direct translumbar puncture of the abdominal aortic aneurysm (AAA) sac after previous endovascular aortic repair. All patients were treated at a single setting in a cardiovascular hybrid operating room with a workstation featuring needle trajectory planning and guidance software. Aneurysm sac size change from the index treatment, freedom from recurrent endoleak after treatment, demographics, risk factors, and procedure factors were analyzed with univariate analysis.

RESULTS

All patients (N = 26; 19 male, 7 female; age range, 59-95 years; mean body mass index, 27.44 ± 3.06 kg/m²) underwent treatment for AAA sac expansion or symptoms. Four patients had failed to respond to previous catheter-directed T2L treatment. The most common risk factors included hypertension, hypercholesterolemia, coronary artery disease, tobacco use, and diabetes. Time to initial endoleak diagnosis ranged from 2 to 1914 days (average, 404 days). Aneurysm size after initial repair was 60.3 ± 7.5 mm; sac size had increased 10.1 ± 6.5 mm at the time of treatment. Onyx (Medtronic, Irvine, Calif) or glue (n-butyl cyanoacrylate) and coil embolization was used in 20 cases, and 6 patients were treated with coiling alone. There was no difference between the patients treated with coils alone and those treated with coils or glue (P > .05) in terms of freedom from failure. Total procedure time was 75.9 ± 40.7 minutes; contrast material volume, 19.9 ± 29 mL; fluoroscopy time, 13.74 ± 12.2 minutes; and radiation dose, 121.16 ± 167.7 mGy. After embolization, the mean sac diameter decreased by 2.2 mm to 67.5 ± 9.8 mm. Average follow-up period was 214 days. In 19 patients, the sac reduced in size between 0.2 and 19.1 mm per 100 days; in 2 patients, there was continued AAA expansion (3.4-4.3 mm per 100 days); there was no change in the sac size in 5 patients after the procedure. There were no AAA ruptures during the study period. Once T2L was treated, the recurrence rate was low at 11.5%.

CONCLUSIONS

This initial multicenter evaluation of the effectiveness of fusion image-guided translumbar obliteration of T2L demonstrated that the technique was effective at all three study centers and showed excellent efficacy to reduce AAA sac size. This may become a more effective and efficient method of treating T2L compared with transarterial or transcaval embolization because of its high success rate and technical ease.

Case series of aortic arch disease treated with branched stent-grafts

Background

Surgical repair of aortic arch pathology is complex and associated with significant morbidity and mortality. Alternative approaches have been developed to reduce these risks, including the use of thoracic stent-grafts with fenestrations or in combination with bypass procedures to maintain supra-aortic trunk blood flow. Branched stent-grafts are a novel approach to treat aortic arch pathology.

Methods

Consecutive patients with aortic arch disease presenting to a single university hospital vascular centre were considered for branched stent-graft repair (October 2010 to January 2017). Patients were assessed in a multidisciplinary setting including a cardiologist, cardiac surgeon and vascular surgeon. All patients were considered prohibitively high risk for standard open surgical repair. The study used reporting standards for endovascular aortic repair and PROCESS (Preferred Reporting of Case Series in Surgery) guidelines.

Results

Some 30 patients (25 men) underwent attempted branch stent-graft repair. Mean age was 68 (range 37–84) years. Eighteen patients had chronic aortic dissection, 11 patients had an aneurysm and one had a penetrating ulcer. Fourteen patients had disease in aortic arch zone 0, six in zone 1 and ten in zone 2. Twenty-five patients had undergone previous aortic surgery and 24 required surgical revascularization of the left subclavian artery. Technical success was achieved in 27 of 30 patients. Four patients had an endoleak (type Ia, 1; type II, 3). The in-hospital mortality rate was three of 30. Mean length of follow-up was 12·0 (range 1·0–67·8) months, during which time 12 patients required an aortic-related reintervention.

Conclusion

Repair of aortic arch pathology using branched stent-grafting appears feasible. Before widespread adoption of this technology, further studies are required to standardize the technique and identify which patients are most likely to benefit.

Evaluation of a new imaging software for aortic endograft planning

OBJECTIVE

The aim of this study was to evaluate a new 3D Workstation workflow (EVAR Assist, Advantage Windows, GE Healthcare, Chalfont, UK) (EA-AW) designed to simplify complex EVAR planning.

PATIENTS AND METHODS

All pre-operative computed tomography (CT) scans of patients who underwent repair at our institution of a complex aortic aneurysm using fenestrated endovascular repair (f-EVAR) between January and September 2014, were reviewed. For each patient, imaging analysis (12 measures: aortic diameters and length and "clock position" of visceral artery) was performed on two different workstations: Aquarius (TeraRecon, San Mateo, CA, USA) and EA-AW. According to a standardized protocol, three endovascular surgeons experienced in aortic endograft planning, performed image analyses and data collection independently. We analyzed an internal assessment between observers (on the Aquarius 3DWS) and an external assessment comparing these results with the planning center (PC) data used to custom the fenestrated endograft of the patients enrolled in this study. Finally, we compared both 3DWS data to determine the accuracy and the reproducibility. A p-value < .05 was considered as statistically significant. Complete agreement between operators was defined as 1.0.

RESULTS

Intra- and inter-observer variability (interclass correlation coefficients - ICC: 0.81-.091) was very low and confirmed the reliability of our planners. The ICC comparison between EA-AW and Aquarius was excellent (> 0.8 for both), thus confirming the reproducibility and reliability of the new EA-AW application. Aortic and iliac necks diameters and lengths were similarly reported with both workstations. In our study, the mean difference in distance and orientation evaluation of target vessels evaluated by the two workstations was marginal and has no impact on clinical practice in term of device manufacturing.

CONCLUSIONS

We showed that complex EVAR planning can be performed with this new dedicated 3D workstation workflow with a good reproducibility.

Current and future perspectives in the repair of aneurysms involving the aortic arch

The repair of aneurysms involving the aortic arch is technically and physiologically demanding. Historically, these aneurysms have been treated using open surgical techniques that require cardiopulmonary bypass and deep hypothermic circulatory arrest. Many patients have been deemed "untreatable" and among those selected for surgery there are reported risks of death in 2% to 16.5% and stroke rates ranging from 2% to 18%. "Hybrid arch repair" combines one of a number of open surgical procedures (to secure a proximal landing zone for an endograft) with subsequent or immediate placement of an endograft in the arch and descending aorta. Although this concept is described as "minimally invasive" because it avoids aortic cross-clamping and hypothermic circulatory arrest, the morbidity and mortality rates remain considerable (mortality 0% to 15%, stroke 0% to 11%). Ongoing development of endograft technology has enabled total endovascular repair of complex aortic aneurysms involving the visceral segment, using fenestrated and branched endografts. Encouraging early results in this anatomy have inspired extension of the concept to include the aortic arch and great vessels. These strategies can be considered in patients generally at high-risk for the conventional procedures. However, the endeavour is at an early stage of its development and the arch poses unique challenges including the potential for stroke, angulation of the arch and the great vessel ostia to the arch, extremely high volume flow, three-dimensional pulsation and rotation with the cardiac cycle and the proximity of the aortic valve and coronary arteries.

Chronic dissection - indications for treatment with branched and fenestrated stent-grafts

The treatment of chronic aortic dissection is a major challenge for the vascular surgeon. Close imaging follow-up after the acute episode frequently identifies dilation of untreated aortic segments. Aortic dissection often extends to both the supra-aortic trunks and to the visceral aorta. The poor medical condition that often characterizes these patients may preclude extensive open surgical repair. Recent advances in endovascular techniques provide a valid alternative to open surgery. These complex lesions can now be managed using thoracic branched and fenestrated endografts. However, clinical data are scarce and only 3 small series from 3 high-volume aortic centers are currently available. Careful anatomical study on 3D workstations is mandatory to select patients that are candidates for complex endovascular exclusion; a specific focus on the available working space within the true lumen, extension to the arch and/or the visceral/renal arteries, and false lumen perfusion of visceral vessels is required. An excellent understanding of those anatomic details demands high-quality preoperative CTA. Intraoperative advanced imaging applications are a major adjunct in the achievement of technical success.

A new score to predict post operative complications after endovascular treatment of thoraco abdominal aortic aneurysms

BACKGROUND

The endovascular treatment of thoraco abdominal aortic aneurysms (TAAA) is a minimally invasive solution. However, patient selection remains a major problem. We have analysed our experience to identify the risk factors for post-operative morbidity and mortality and to construct a scoring system to identify those patients likely to benefit from this treatment.

METHODS

We have analysed a consecutive cohort of patients treated electively for TAAA using endovascular techniques between 2006 and October 2012. All data were collected prospectively. The risk factors associated with spinal cord ischemia (SCI), the need for post-operative dialysis and 30 day mortality were determined using multivariate statistical techniques and a logistic regression model including all variables that were significant on univariate analysis (p < 0.05). A predictive score was calculated using a Received Operating Characteristic (ROC) curve, defining best specificity and sensibility.

RESULTS

We analysed the data from 123 patients (median age 70 years). The 30 day mortality rate was 8% (10 patients). The SCI rate was 6% (7 patients). One patient (1%) required long-term dialysis after the aortic procedure. The cumulative early mortality, SCI and permanent dialysis rate was 14% (17 patients). In multivariate analysis, adverse outcome was associated with advanced age (OR = 1.110 ; p = 0.022), and Crawford type I or II or III (OR = 9.292 ; p = 0.002) as compared with Crawford type IV. Pre-operative beta blocker (BB) treatment was a protective factor (OR = 0.099 ; p = 0.005). A predictive score was then constructed : Score = -10.060 + 0.104x(A) +2.229x(B) -2.315x(C) (A = patient age ; B = 1 if TAAA Crawford type 1, 2 or 3, 0 if TAAA type 4 ; C = 1 if on-going BB treatment (30 days pre-surgery minimum), 0 if none). Its sensitivity and specificity were 88% and 89% respectively.

CONCLUSIONS

We propose a simple predictive scoring system. This tool is useful in predicting the most feared complications after endovascular TAAA repair and has potential use in the identification and counselling of vulnerable patients being considered for surgery. More data are needed to refine the prediction of individual operative risks.

Techniques to reduce radiation and contrast volume during EVAR

There is a large variability observed in the literature regarding radiation exposure and contrast volume injection during endovascular aortic repair (EVAR). Reducing both in order to decrease their respective toxicities must be a priority for the endovascular therapist. Radiation dose reduction requires a strict application of the "as low as reasonably achievable" principles. Firstly, all X-ray system settings should be defaulted to low dose, and fluoroscopic time reduced as much as possible. Digital subtraction angiography runs should be replaced by recorded fluoroscopy runs when possible. Magnification should be avoided, whereas collimation should be systematic to minimize scatter radiation and focus only on the area of interest. Advanced imaging modes can also contribute to dose reduction. For instance, image fusion can facilitate endovascular navigation, and allow table and C-arm positioning without fluoroscopy. In our experience, routine use of image fusion during EVAR significantly reduces both radiation exposure and contrast volumes during complex EVAR. To make these imaging modes useable in real life settings, the X-ray system should be fully controlled by the operator from table side. Reducing iodinated contrast volume, while maintaining image quality, can also be achieved through the use of automated contrast injectors. Additionally, alternative contrast agents, like carbon dioxide (CO2) and gadolinium, have also been evaluated and can be used in specific cases. Contrast-enhanced ultrasound and intravascular ultrasonography are currently developed as potential alternatives to both iodinated contrast use and X-ray during EVAR. Lastly, specific education and training of operators in radiation protection are essential.

An optimal combination for EVAR: low profile endograft body and continuous spiral stent limbs

AIM

to evaluate the outcomes of EVAR performed with a new generation of bifurcated endografts and limbs.

METHODS

prospectively collected data from fifty consecutive patients with abdominal aortic aneurysms (AAA) treated at our institution with a Low Profile Zenith(®) bifurcated body/Zenith(®) Spiral-Z legs combo were analysed. AngioCT scans and Ultrasound exams were performed prior to discharge. Ultrasound examination was repeated 6 months after the procedure to assess endograft patency and to depict endoleaks

RESULTS

Median age was 70.6 years [50-88] and median ASA score was 3 [2-4]. Median aortic diameter was 56 mm [49-81]. Of the 100 external iliac access vessels, 14 had a diameter of 6 mm or lower. All endografts were successfully implanted. Post-operative Ultrasound examination and angioCT scan depicted both 1 type Ia, and 10 and 19 type 2 endoleaks respectively. An asymptomatic thrombosis of the left external iliac artery distal to the endograft limb was also depicted. 30-day mortality rate was 0%. Two patients died respectively three and four months after EVAR. Both deaths were not aneurysm related. All patients underwent an ultrasound exam 6-12 months after EVAR. All endografts main bodies and limbs were patent. Five endoleaks were depicted, all were type II endoleaks (the early type Ia endoleak had sealed spontaneously; it was confirmed by an angioCT scan). One patient presented a significant stenosis of the left iliac limb at the level of a narrow and calcified aortic bifurcation. It was successfully treated by bilateral iliac angioplasty and kissing balloon stenting.

CONCLUSIONS

EVAR performed with the Zenith LP main body in combination with Spiral-Z Iliac Legs is safe and effective. No limb occlusions were diagnosed at the 6 month follow up even in challenging iliac anatomies usually considered as contra indications for EVAR. Our first results are most satisfying and calling to be completed by a longer follow up.

Chronic type B dissections: are fenestrated and branched endografts an option?

While there are centers reporting encouraging outcomes after endovascular repair of thoracoabdominal aortic aneurysms, chronic dissections (a specific etiological subgroup of thoracoabdominal aneurysms) present an even greater technical and clinical challenge. There are particular technical issues associated with the management of the proximal sealing zone, the need to work in a narrow aortic lumen and also to maintain perfusion of all target (visceral and supra-aortic) vessels including those perfused by the false lumen. We present here the various endovascular options available for the treatment of these complex aortic lesions.