Contrast Free Duplex-Assisted EVAR in Patients with Chronic Renal Insufficiency

Comparative Effectiveness of Intravascular Ultrasound Versus Angiography in Abdominal and Thoracic Endovascular Aortic Repair: Systematic Review and Meta-Analysis

The effectiveness of intravascular ultrasound (IVUS) with angiography compared with angiography guidance alone in treating aortic conditions, such as dissections, aneurysms, and blunt traumatic injuries, remains unclear. This systematic review and meta-analysis evaluates the current literature for IVUS use during thoracic endovascular aortic repair (TEVAR) and abdominal endovascular aortic repair (EVAR). A comprehensive search of MEDLINE, EMBASE, and Cochrane CENTRAL databases was conducted in March 2024 adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies comparing outcomes of TEVAR/EVAR with and without IVUS were identified. The outcomes of interest included contrast volume, fluoroscopy and procedural time, perioperative endoleak, and reinterventions and all-cause mortality during follow-up. Data with 95% confidence intervals (CIs) were extracted. Pooled analysis was performed using a random-effect model. Subgroup analysis was performed stratified by the condition being treated. Risk of bias was assessed using the Newcastle-Ottawa Scale for observational studies. A total of 4,219 patients (n = 2,655 IVUS and n = 1,564 non-IVUS) from 9 observational studies were included. The IVUS group exhibited a reduction in contrast agent volume (weighted mean difference -34.65 mL, 95% CI -54.73 to -14.57) and fluoroscopy time (weighted mean difference -6.13 minutes, 95% CI -11.10 to -1.15), with no difference in procedural time. The perioperative type I and III endoleak occurrences were similar (risk ratio 2.36, 95% CI 0.55 to 10.11; risk ratio 0.72, 95% CI 0.09 to 5.77, respectively). Reintervention and mortality during follow-up were comparable (hazard ratio 0.80, 95% CI 0.33 to 1.97; hazard ratio 0.75, 95% CI 0.47 to 1.18, respectively). All the included studies had small risks of bias. In conclusion, this meta-analysis provides evidence that IVUS enables the safe deployment of TEVAR/EVAR with reduced contrast agent and radiation exposure.

Contrast-Free Endovascular Aneurysm Repair Combined With Fibrin Sealant Filling for Treating Abdominal Aortic Aneurysm: Technical Note

INTRODUCTION

Endovascular aneurysm repair using iodinated contrast agents risks contrast-induced nephropathy, especially in high-risk patients. This technical note describes a contrast-free endovascular aneurysm repair (EVAR) protocol using preoperative imaging measurement and fibrin sealant (FS) filling.

TECHNIQUE

Preoperative imaging measurement and intraoperative guidewire manipulation facilitated anatomical identification without contrast. After endograft deployment, the aneurysm sac was filled with FS if endoleak was indicated by pressure fluctuations.

RESULT

Between 2017 and 2020, 6 high-risk patients underwent contrast-free EVAR with FS filling. Complete exclusion was achieved in all cases. Over follow-up, no endoleaks, deterioration in renal function, or other complications were observed.

CONCLUSION

Contrast-free EVAR with FS filling shows early feasibility as an alternative technique for contrast-induced nephropathy (CIN) high-risk patients, while larger studies with long-term monitoring are imperative to validate outcomes.

CLINICAL IMPACT

This study showcases a contrast-free EVAR technique with fibrin sealant filling for high-risk CIN patients. It offers a safer approach for those with renal challenges, reducing CIN risk. The technique's feasibility in a small cohort suggests its utility in treating AAA without iodinated contrast, crucial for patients with specific health risks. For clinicians, it introduces a method that decreases nephrotoxic risks, potentially changing practice for vulnerable patients.

Kidney Function, Male Gender, and Aneurysm Diameter Are Predictors of Acute Kidney Injury in Patients with Abdominal Aortic Aneurysms Treated Endovascularly

Abdominal aortic aneurysm (AAA) is a degenerative disease of the aortic wall with potentially fatal complications. The widespread adoption of endovascular aneurysm repair (EVAR), which is less invasive and equally (if not more) effective for abdominal aortic aneurysms (AAA), is due to the obvious advantages of the procedure compared to the traditional open repair. As the popularity of endovascular procedures grows, related complications become more evident, with kidney damage being one of them. Although acute kidney injury following EVAR is relatively common, its true incidence is still uncertain. The purpose of this study was to assess the incidence of acute kidney injury among patients treated with endovascular repair of ruptured AAA. In addition, we aimed to determine the predictors of PC-AKI in patients with abdominal aortic aneurysm treated with EVAR.

PATIENTS AND METHODS

We retrospectively analyzed a prospective registry of abdominal aortic aneurysm of 247 patients operated endovascularly at a single center between 2015 and 2021. Due to a lack of clinical data, data of 192 patients were reviewed for postcontrast acute kidney injury. Additional comorbidities were included in this study: hypertension, diabetes mellitus, atrial fibrillation, chronic coronary syndrome, COPD, and chronic kidney disease. Follow-up examinations were performed before the procedure and 48 h after contrast administration.

RESULTS

The group of 36 patients developed PC-AKI, which is 19% of the entire study population. Hypertension, diabetes, chronic kidney disease, male gender, and incidence of PC-AKI were more prevalent in patients with higher aortic aneurysm diameter ≥67 mm. In multiple regression analyses, independent predictors of PC-AKI were serum creatinine, chronic kidney disease, male gender, and aortic aneurysm diameter ≥67 mm.

CONCLUSIONS

One of the major complications after EVAR is acute kidney injury, which is linked to higher death and morbidity rates. Independent risk factors for postcontrast acute kidney injury were chronic kidney disease, male gender, and aortic diameter. Only aortic diameter could be modifiable risk factor, and earlier surgery could be considered to yield better outcomes. More research is critically needed to determine how AKI affects long-term outcomes and to look at preventive options.

Fully Ultrasound-Assisted Endovascular Aneurysm Repair (EVAR): preliminary report

BACKGROUND

Reducing fluoroscopy times and iodine contrast administration during endovascular exclusion (EVAR) of infrarenal aortic aneurysms (AAA) remains a challenge. The purpose of this study was to evaluate the preliminary results of a fully ultrasound-assisted EVAR without iodine contrast administration.

METHODS

Twentyseven consecutive patients, underwent an elective IVUS-assisted EVAR with final CEUS control of correct aneurysm exclusion. In no case intraprocedural injection of iodine contrast medium was performed. The primary study's endpoints were the overall duration of the procedure, duration of fluoroscopy, cumulative radiation dose, the length of intraoperative CEUS control and the comparison of findings between intraoperative CEUS and CT-scan at one month.

RESULTS

Mean duration of the procedure was 130 ± 35 minutes. Overall duration of fluoroscopy was 22 ± 18 minutes. Mean radiation dose was 66 mGy (range, 24 - 82). The mean length of CEUS final control was 8 ± 2 minutes. No type I or type III endoleak was detected either at CEUS or at angio-CT scan at one month from EVAR. CEUS revealed a type II endoleak in 6 patients (22%) , compared to 9 type II endoleaks (33%) detected at angio-CT scan one month after the procedure (p = 0.5).

CONCLUSIONS

Fully ultrasound (IVUS and CEUS) -assisted EVAR is safe, feasible and reliable, completely eliminating the need for iodine contrast medium and reducing the radiation exposure for both patients and surgeons.

First-in-Human Clinical Application of the Medyria TrackCath System in Endovascular Repair of Complex Aortic Aneurysms (ACCESS Trial): A Prospective Multicenter Single-Arm Clinical Trial

PURPOSE

The Medyria TrackCath Catheter (MedTCC) is an innovative, thermal convection-based blood flow velocity (BFV) tracking catheter that may be used during complex aortic endovascular procedures for identification and catheterization of target orifices. The ACCESS Trial analyzes the safety and performance of the MedTCC for targeted vessel catheterization to generally evaluate the feasibility of thermal convection-based BFV.

MATERIALS AND METHODS

We performed a first-in-human, proof-of-concept, prospective single-arm multicenter clinical trial between March 2018 and February 2019 in patients who underwent endovascular aortic procedures at 4 high-volume centers. During these procedures, the MedTCC was advanced over a guidewire through the femoral access. The D-shape was enfolded in the reno-visceral part of the aorta and target orifices were identified and catheterized with a guidewire via the side port of the MedTCC through BFV tracking. BFV measurements were performed at baseline (Baseline-BFV), alignment to the orifice (Orifice-BFV), and following catheterization (Confirmation-BFV) to prove correct identification and catheterization of target orifices. The procedural success rate, the catheterization success rate, procedure-related parameters, and (serious) adverse events ((S)AE) during the follow-up were analyzed.

RESULTS

A total of 38 patients were included in the safety group (SG) and 26 in the performance group (PG). The procedural success rate was 89% (PG), the MedTCC catheterization success rate was 98% (PG). The MedTCC reliably measured BFV changes indicated by significant differences in BFV between Baseline-BFV and Orifice-BFV (p<0.05). Median (interquartile range; IQR) fluoroscopy time per orifice was 5.0 (1.5-8.5) minutes [total surgery 49 (26-74) minutes], median (IQR) contrast agent used per orifice was 1.0 (0-5.0) mL [total surgery 80 (40-100) mL], and median (IQR) MedTCC-based procedural time was 3.0 (2.0-6.0) minutes. There was no device-related SAE.

CONCLUSIONS

The ACCESS Trial suggests that BFV measurement allows for reliable target orifice identification and catheterization. The use of MedTCC is safe and generates short fluoroscopy time and low contrast agent use, which in turn might facilitate complex endovascular procedures.

Intravascular Ultrasound-Assisted Endovascular Exclusion of Penetrating Aortic Ulcers

BACKGROUND

Penetrating aortic ulcer (PAU) is an atherosclerotic lesion penetrating the elastic lamina and extending into the media of the aorta. It may evolve into intramural hematoma, focal dissection, pseudoaneurysm, and eventually rupture. The purpose of this study was to evaluate the effectiveness of a totally intravascular ultrasound (IVUS)-assisted endovascular exclusion of PAU.

METHODS

Thirteen consecutive patients (median age 66 years) underwent IVUS-assisted endovascular exclusion of PAU. The primary end points were fluoroscopy time, radiation dose, and occurrence of type I primary endoleak. Secondary end points were postoperative mortality and morbidity, arterial access complications, postoperative length of stay in the hospital, and occurrence of type II endoleaks.

RESULTS

The median fluoroscopy time was 4 min (4-5). The median radiation dose was 4.2 mGy (3.9-4.5). A proximal and distal landing zone of at least 2 cm could be obtained in all the patients. No patient presented a type I endoleak. No postoperative mortality, no morbidity, or arterial access complication was observed. The median length of postoperative stay in the hospital was 2 days (2-3). The median length of follow-up was 25 months (9.2-38.7). One late type II endoleak was observed (7.7%), because of reflux from the intercostal arteries, without the need for additional treatment.

CONCLUSIONS

IVUS-assisted endovascular treatment of PAU allows durable exclusion of PAU with a short fluoroscopy time and no need for injection of contrast media. Further series are needed to confirm the results of this preliminary study.

Peroperative Intravascular Ultrasound for Endovascular Aneurysm Repair versus Peroperative Angiography: A Pilot Study in Fit Patients with Favorable Anatomy

BACKGROUND

The aim of this study was to compare intravascular ultrasound (IVUS) assistance for endovascular aortic aneurysm repair (EVAR) to standard assistance by angiography.

METHODS

From June 2015 to June 2017, 173 consecutive patients underwent EVAR. In this group, 69 procedures were IVUS-assisted with X-ray exposure limited to completion angiography for safety purposes because an IVUS probe does not yet incorporate a duplex probe (group A), and 104 were angiography-assisted procedures (group B). All IVUS-assisted procedures were performed by vascular surgeons with basic duplex ultrasound (DUS) training. The primary study endpoints were mean radiation dose, duration of fluoroscopy, amount of contrast media administered, procedure-related outcomes, and renal clearance expressed as the glomerular filtration rate (GFR) before and after the procedure. Secondary endpoints were operative mortality, morbidity, and arterial access complications.

RESULTS

Mean duration of fluoroscopy time was significantly lower for IVUS-assisted procedures (24 ± 15 min vs. 40 ± 30 min for angiography-assisted procedures, P < 0.01). Moreover, mean radiation dose (Air KERMA) was significantly lower in IVUS-assisted procedures (76m Gy [44-102] vs. 131 mGy [58-494]), P < 0.01. IVUS-assisted procedures required fewer contrast media than standard angiography-assisted procedures (60 ± 20 mL vs. 120 ± 40 mL, P < 0.01). The mean duration of the procedure was comparable in the two groups (120 ± 30 min vs. 140 ± 30 min, P = 0.07). No difference in renal clearance before and after the procedure was observed in either of the two groups (99.0 ± 4/97.8 ± 2 mL/min in group A and 98.0 ± 3/97.6 ± 5 mL/min in group B) (P = 0.28). The mean length of follow-up was nine months (6-30 months). No postoperative mortality, morbidity, or arterial access complications occurred. No type 1 endoleak was observed. Early type II endoleaks were observed in 21 patients (11%), 12 in the angiography-assisted group (11%) and nine in the IVUS-assisted group (12%). They were not associated with sac enlargement ≥5 mm diameter and therefore did not require any additional treatment.

CONCLUSIONS

Compared with standard angiography-assisted EVAR, IVUS significantly reduces renal load with contrast media, fluoroscopy time, and radiation dose while preserving endograft deployment efficiency. Confirmation from a large prospective study with improved IVUS probes will be required before IVUS-assisted EVAR alone can become standard practice.