A Pilot Study of Endovascular Repair for Ruptured Aortic Aneurysms With the Use of Carbon Dioxide Angiography Alone.

INTRODUCTION: Endovascular aortic repair (EVAR) of a ruptured abdominal aortic aneurysm (rAAA) has become a common approach. Hemorrhagic shock associated with the use of iodinated contrast medium (ICM) increases the risk of acute kidney injury (AKI). Theoretically, eliminating ICM from EVAR can decrease that risk. The aim of this pilot study was to analyze the feasibility and safety of emergent EVAR performed with the exclusive use of carbon dioxide (CO2) for a rAAA. METHODS: Since 2021, all consecutive rAAAs with hemorrhagic shock and suitable anatomical criteria for a standard endograft have been treated by EVAR with the exclusive use of CO2 using an automated CO2 injector (Angiodroid SpA, San Lazzaro di Savena, Italy). RESULTS: Eight percutaneous EVARs were performed under local anesthesia. Median age was 78 (interquartile range [IQR]=6) years, 5 patients were male. The technical success was 100%, the 30-day mortality was 25% (n=2), the median amount of administered CO2 was 400 (IQR=60) ml. The median change in serum creatinine level between admission, post-operative and 30-day values was an increase of 0.14 mg/dL and a decrease of 0.11 mg/dL, respectively. Post-operative AKI occurred in the two patients who died. All 6 surviving patients showed sac shrinkage >5 mm, and no reinterventions at a median follow-up of 10 months. CONCLUSIONS: Endovascular repair of rAAA with the exclusive use of CO2 as contrast agent is technically feasible and safe. Further studies are needed to determine whether CO2 increases survival rate and limits the progression of renal dysfunction after endovascular repair of rAAA. CLINICAL IMPACT: The recorded rate of post-operative AKI after endovascular repair of rAAA performed with the use of CO2 found in this pilot study was significantly lower than the one reported in the literature with the use of ICM. Our hyphotesis is that the use of CO2 during rEVAR might increase survival rate and limits the progression of renal dysfunction.

A comparative analysis of anatomical variations of popliteal artery and its branches in concomitant aneurysmal disease.

OBJECTIVES: Open or endovascular treatment of popliteal artery aneurysms (PAAs) is still debated. Data about the popliteal artery anatomy and its branches are essential to plan a surgical approach. The aim of this study was to report the anatomical variations of the popliteal artery and its branches in a population with aneurysmal disease and compare them with a standard population with non-aneurysmal disease. METHODS: A retrospective review of consecutive patients who underwent surgical PAA repair in our center between January 2011 and December 2020 was performed. One-hundred-forty-six limbs in 128 patients underwent PAA treatment (Group 1). Computed tomography angiography images using a 128-section configuration were reviewed for anatomical variations of the popliteal artery and its branches. A control population of 178 limbs in 89 patients with non-aneurysmal disease was used to compare the outcomes (Group 2). All limbs were classified according to Kim's classification. The two groups were analyzed and compared by means of nonparametric Pearson chi-square test. RESULTS: Both groups were homogeneous in terms of demographics, risk factors, and clinical presentation. In Group 1, the limbs with PAA were classified as type IA, 133 (91.1%); type IB, 2 (1.4%); type IC, 0; type IIA1, 1 (0.7%); type IIA2, 1 (0.7%); type IIB, 4 (2.7%); type IIC, 0; type IIIA, 3 (2.1%); type IIIB, 0; and type IIIC, 2 (1.4%). In Group 2 the limbs with non-aneurysmal disease were classified as type IA, 163 (91.6%); type IB, 5 (2.8%); type IC, 1 (0.6%); type IIA1, 1 (0.6%); type IIA2, 3 (1.7%); type IIB, 2 (1.1%); type IIC, 0; type IIIA, 3 (1.7%); type IIIB, 0; and type IIIC, 0. No difference in terms of anatomy of the popliteal artery and its branches was found between the two groups (P = NS). CONCLUSIONS: Knowledge of anatomical variations of the popliteal artery and its branches is mandatory in case of the surgical approach. Anatomy in PAA patients is not different. Studies with larger population size are needed to validate these outcomes.

Benefits and Role of Carbon Dioxide Angiography in Case of Misalignment Between Fenestration and Target Vessel During Fenestrated Endovascular Aneurysm Repair.

PURPOSE: To report the benefits and the role of carbon dioxide (CO2) angiography in case of misalignment between fenestration and target vessel during fenestrated endovascular aneurysm repair (F-EVAR). TECHNIQUE: During F-EVAR, misalignment between fenestration and target vessel is a potentially catastrophic complication. In 2 patients, we experienced that one of the target vessels were not visible during standard angiography in different projections after positioning a fenestrated graft and even after cannulation of the corresponding fenestration. In both cases, the graft was sealed to the aortic wall but not in the predictable position. Consequently, acute occlusion of the target vessel was hypothesized. However, CO2 angiography was useful to evaluate patency of the target vessel clarifying the relative position of the fenestration versus the target vessel. Rescue maneuvers were feasible under the guidance of CO2 angiography in order to obtain the cannulation of both renal arteries. In both cases, the procedure was successfully accomplished. CONCLUSION: In case of misalignment of a fenestration during F-EVAR and non-visualization of the target vessel with standard angiography, CO2 angiography could have the unique and complementary role of clarifying the patency and position of the target vessel. In addition, CO2 could guide the rescue maneuvers.

2D perfusion angiography as quantitative method to evaluate iloprost effect on foot circulation.

Background: Two-dimensional (2D) perfusion angiography is useful for the evaluation of foot perfusion in patients with critical limb-threatening ischemia (CLTI). Iloprost is a synthetic prostacyclin analogue presenting vasodilating properties. Aim of this study was to demonstrate the utility of 2D perfusion angiography as quantitative method to evaluate iloprost effect on foot circulation. Patients and methods: Between January 2020 and June 2020 25 patients with CLTI underwent below-the-knee (BTK) endovascular revascularization, intra-arterial administration of iloprost, and assessment of foot perfusion by 2D perfusion angiography. Iloprost was administered as an intra-arterial bolus of 3 µg over 1-3 minutes immediately after BTK revascularization. The 2D perfusion angiography was performed in a standardized manner with a 5-F catheter placed into the popliteal artery. A wide region of interest (ROI) was identified to assess the foot perfusion. Time-density curves were calculated by the perfusion software. Changes of the overall time-density curves before and after the administration of iloprost were evaluated. Results: Endovascular revascularization was successful in all cases. The mean reduction of systolic pressure value after iloprost administration was 23.1 mmHg. Eight patients (32%) experienced a minor complication (6 cutaneous rush, 2 symptomatic hypotension >40 mmHg). In 20 patients the time-density curves under ROI increased after the intra-arterial administration of iloprost (+31.6%, range from +4.9% to +78.7%). Five patients had no modification or a slight decrease of foot perfusion after iloprost administration (non-responders patients). Conclusions: Patients undergoing intra-arterial administration of iloprost accounted for a not negligible rate of minor complications. 2D perfusion angiography was valuable as quantitative method to evaluate the iloprost effect on foot circulation. This technique could be useful to classify the patients in responders or non-responders to iloprost therapy.

Association of 2D Perfusion Angiography and Wound Healing Rate in Combined Femoro-popliteal and Below-the-Knee Lesions in Ischemic Patients Undergoing Isolated Femoro-popliteal Endovascular Revascularization.

The aim of this study was to demonstrate the association between 2-dimensional (2D) perfusion angiography and wound healing rate in patients with combined femoro-popliteal and below-the-knee lesions in critical limb-threatening ischemia (CLTI) and foot wounds undergoing isolated femoro-popliteal endovascular revascularization. Between January and June 2019, 24 patients with multilevel CLTI and foot wounds underwent isolated femoro-popliteal endovascular revascularization. In all of them, an assessment of foot perfusion by 2D perfusion angiography was performed. To evaluate the foot perfusion, a region of interest was identified, and time-density curves were calculated. Changes of the overall time-density curves were evaluated together with transcutaneous oximetry (TcPO2) using bivariate correlation (Pearson correlation coefficient) and associated with 6-month wound healing. The mean increase of time-density curves was 212.2% (range from +9.8% to +1984.9%) and the mean increase of TcPO2 was 116.4% (range from -4.7% to 485.7%). No significant association between time-density curves and TcPO2 values (Pearson correlation coefficient: -0.24) was observed (P = .3). At 6 months, wound healing occurred in 15 of 24 (62.5%) patients. In conclusion, this preliminary experience confirmed that 2D perfusion angiography associates with wound healing rate in CLTI patients with ischemic foot wounds and combined femoro-popliteal and below-the-knee lesions who are undergoing isolated femoro-popliteal endovascular revascularization. No association between time-density curves and TcPO2 values was observed.

A comparison study of radiation exposure to patients during EVAR and Dyna CT in an angiosuite vs. an operating theatre.

The aim of this study was to assess the patient dosimetric impact of endovascular abdominal aortic aneurysm repair (EVAR), both in an operating theatre (OR) and in an angiosuite (AS), with the facility of Dynamic CT (Dyna CT, Siemens AG, Berlin, Germany). One hundred and forty-six consecutive EVAR procedures dating from May 2011 to March 2013 were analysed. These were performed either in an OR (n = 97) using a mobile C-arm or in an AS (n = 49) equipped with a ceiling-mounted angiography system. Air kerma area product (P(KA)) and total air kerma at reference point (K(a,r)) values were reported for all procedures and Dyna CT. Radiation exposure during EVAR was quite low in the majority of patients but nearly 50 % higher if performed in AS vs. OR. Median Dyna CT K(a,r) was the same as an entire EVAR procedure in OR. The higher patient's radiation exposure recorded in the AS should be balanced with the technical advantages given to the EVAR procedure.