Adrenal vein sampling with gadolinium contrast medium in a patient with florid primary aldosteronism and iodine allergy

We describe a 35-year-old woman who was allergic to iodine contrast medium and was diagnosed with primary aldosteronism (PA) based on functional confirmatory tests. She was suspected to have unilateral PA because of marked hypertension, spontaneous hypokalemia, high plasma aldosterone, reduced plasma renin activity, and a right hypodense adrenal tumor. She wanted to become pregnant and requested adrenalectomy instead of medical treatment with mineralocorticoid receptor antagonists. Localization of PA by adrenal vein sampling (AVS) was necessary, but angiography with iodine contrast medium was not possible because of her allergy. AVS was performed using gadolinium contrast agent (gadoterate meglumine) instead of iodine, in combination with computed tomography angiography (CTA). In AVS, before and after adrenocorticotropin (ACTH) loading, 12 blood samples were drawn from the right adrenal vein, left adrenal central vein, left adrenal common duct, left and right renal veins, and the lower inferior vena cava with only 5 mL of gadolinium medium. There were no complications during AVS. Examination revealed an elevated aldosterone/cortisol ratio on the right side, lateralized ratio of 7.4, and contralateral ratio of 0.76; the patient was diagnosed with right unilateral PA. She underwent right adrenalectomy and showed improvements in aldosterone level from 312.4 pg/mL to 83.0 pg/mL, potassium from 3.0 mEq/L to 3.9 mEq/L, and systolic blood pressure from 138 mm Hg to 117 mm Hg. In PA patients with iodine allergy, AVS can be performed safely and precisely using gadolinium contrast combined with CTA.

Image quality and safety of automated carbon dioxide digital subtraction angiography in femoropopliteal lesions: Results from a randomized single-center study

PURPOSE

To evaluate the image quality and the safety of automated carbon dioxide (CO₂) digital subtraction angiography (DSA).

MATERIALS AND METHODS

Fifty patients receiving DSA for femoropopliteal peripheral arterial disease (PAD) were enrolled in this single-center prospective study. All patients received iodinated contrast media (ICM) and CO₂ as a contrast agent in the same target lesion. As a primary endpoint, four raters independently evaluated the angiography images based on overall image quality, visibility of collaterals, and assessment of stenoses/occlusions. Inter-rater agreement was assessed using the intraclass correlation coefficient (ICC) and differences between the raters were evaluated using Friedmann's test. Secondary endpoints were procedure safety and patient pain assessment.

RESULTS

Inter-rater agreement between CO₂-DSA and ICM-DSA images was fair to excellent for overall image quality (ICC: 0.399-0.748), fair to excellent for the visibility of collaterals (ICC: 0.513-0.691), and poor to excellent for the assessment of stenoses/occlusions (ICC: -0.065-0.762). There were no significant differences between the raters. Two patients had a hematoma, one reported pain related to puncture, one became nauseous, and one vomited. No other adverse events were observed. Reported pain scores were significantly higher for CO₂-DSA vs. ICM-DSA (1.25 vs. 0625; p < 0.028).

CONCLUSION

CO2-DSA using automated injection system in combination with proprietary post-processing software is safe and comparable diagnostic test compared to ICM-DSA.

Feasibility of Intraoperative Fusion Imaging Using Non-Contrast CT Scan for EVAR in Ruptured Abdominal Aortic Aneurysm

Introduction

Acute renal failure is a frequent major complication (24%) of endovascular repair for ruptured abdominal aneurysm (rAAA). Iodinated contrast media is known to be nephrotoxic. This report describes a case of endovascular aneurysm repair (EVAR) under fusion imaging guidance in a patient diagnosed with a rAAA after non-contrast CT. Written consent was obtained from the patient.

Report

A 73 year old patient with stage IV chronic kidney failure and contrast-induced nephropathy was diagnosed with rAAA using non-contrast CT. Subsequently, the patient was treated with EVAR using fusion imaging.

Discussion

EVAR with fusion imaging after non-contrast CT was safe in a patient with rAAA. It could represent an option for patients with acute renal failure in emergency settings.

Endovascular Infrarenal Aortic Aneurysm Repair Performed in a Hybrid Operating Room Versus Conventional Operating Room Using a C-Arm

BACKGROUND

To compare contrast usage and radiation exposure during endovascular aneurysm repair (EVAR) using mobile C-arm imaging in a conventional operating room (OR) or fixed angiographic equipment in a hybrid OR (HR).

METHODS

A retrospective unicenter study from May 2016 to August 2019. All consecutive patients undergoing standard EVAR were included. Patients were divided into 2 groups. Group OR included EVARs performed in a conventional OR with a mobile C-arm (May 2016 to April 2018) and group HR included EVARs performed with a fixed angiographic equipment in an HR (May 2018 to August 2019). Data collected included patient demographics, aneurysm diameter, neck length, radiation dose: median dose-area product (DAP), fluoroscopy time, total operative time, contrast use, and 30-day clinical outcomes.

RESULTS

A total of 77 patients were included in the study (42 patients in group OR and 35 patients in group HR). There was no difference in age, body mass index (BMI), mean aneurysm, and neck length between groups. Patients in the group HR received less contrast volume (108.6 mL [±41.5] vs. 162.5 mL [±52.6]; P < 0.001), but higher radiation dose (154 Gy cm² [±102.9] vs. 61.5 Gy cm² [±42.4]; P < 0.001). There were no differences in fluoroscopy time (20.4 min [±8.5] vs. 23.2 min [±12.4]; P = 0.274) and total operative time (106.4 [±22.3] vs. 109.4 [±25.8]; P = 0.798). No difference was found in terms of 30-day complication rates or operative mortality between groups. DAP was positively correlated with BMI in the group OR (Spearman's rank correlation coefficient r_s, 0.580; P < 0.001), but no correlation could be seen in the group HR (r_s, 0.408; P = 0.028).

CONCLUSIONS

Routine EVAR performed in a hybrid fixed-imaging suite may be associated with less contrast usage, but higher radiation exposure in our center. The significantly higher radiation exposure when the mobile C-arm is replaced by an HR should not be underestimated.

Transjugular intrahepatic portosystemic shunt creation: three-dimensional roadmap versus CO2 wedged hepatic venography

OBJECTIVES

The blind portal vein puncture remains the most challenging step during transjugular intrahepatic portosystemic shunt (TIPS) creation. We performed a prospective randomised clinical trial to compare three-dimensional (3D) roadmap with CO₂ wedged hepatic vein portography for portal vein puncture guidance.

METHODS

Between March 2017 and May 2017, 30 patients were enrolled and randomly allocated to the study group (3D roadmap) or the control group (CO₂ wedged hepatic vein portography).

RESULTS

Technical success of TIPS procedures was achieved in all 30 patients. The mean number of needle passes was significantly lower in the study group (2.0 ± 1.0) compared to the control group (3.7 ± 2.5; p = 0.021). A total of six (40%) patients in the study group and three (20%) in the control group required only one puncture for the establishment of TIPS. There were no significant differences in total fluoroscopy time (p = 0.905), total procedure time (p = 0.199) and dose-area product (p = 0.870) between the two groups.

CONCLUSIONS

3D roadmap is a safe and technically feasible means for portal vein puncture guidance during TIPS creation, equivalent in efficacy to CO₂ wedged hepatic vein portography. This technique could reduce the number of needle passes, thereby simplifying the TIPS procedure.

KEY POINTS

• 3D roadmap can be used to guide portal vein puncture. • Compared with CO ₂ venography, 3D roadmap reduced the number of needle passes. • 3D roadmap has a potential to simplify the TIPS procedure.

Real-Time 3D CT Image Guidance for Transjugular Intrahepatic Portosystemic Shunt Creation Using Preoperative CT: A Prospective Feasibility Study of 20 Patients

OBJECTIVE

The purpose of this study is to prospectively evaluate the feasibility and efficacy of real-time 3D CT image guidance during transjugular intrahepatic portosystemic shunt (TIPS) creation.

SUBJECTS AND METHODS

Between October 2013 and December 2013, a total of 20 patients were prospectively enrolled in the present study. Previously acquired portal venous phase CT datasets and intraoperative CT datasets were registered on a dedicated workstation. We accomplished semiautomatic registration for the datasets of 11 of 20 patients (55%), and we performed manual registration for the datasets of the remaining nine patients. The selected volume of interest of the CT image showing the portal vein vasculature was overlaid onto the fluoroscopic display to provide real-time 3D CT image guidance during the procedure.

RESULTS

For all 20 patients, TIPS procedures were successfully performed by the same operator. The mean (± SD) number of needle passes required for portal vein entry was 1.8 ± 1.1 passes (range, 1-5 passes). The mean duration of radiographic fluoroscopy was 3.5 ± 1.1 minutes for portal vein entry and 11.4 ± 2.1 minutes for the whole procedure. The mean radiation dose used for the whole TIPS procedure was 295.5 ± 66.6 Gy · cm². No major technical complications were observed.

CONCLUSION

Real-time 3D guidance with the use of preoperative CT is feasible, safe, and effective for assisting in the creation of TIPS. This approach may result in a shorter procedural time and less radiation exposure. However, future studies are required to compare this method with other mapping techniques.

Carbon dioxide as a substitute for iodine contrast in arteriography during embolectomy

Acute limb ischemia can be potentially harmful to the limb and life threatening. Renal failure is a possible outcome associated with release of products of ischemic limb reperfusion. Some authors reported the benefit of performing angiography after embolectomy, even though iodine contrast is also nephrotoxic. We report a case of embolectomy on a patient with renal insufficiency in whom carbon dioxide was used as a substitute for iodine contrast.

Carbon dioxide digital subtraction angiography as an option for detection of endoleaks in endovascular abdominal aortic aneurysm repair procedure

OBJECTIVE

The purpose of this study was to evaluate carbon dioxide digital subtraction angiography (CO2-DSA) as an option for the detection of endoleaks (ELs) in the endovascular abdominal aortic aneurysm repair (EVAR) procedure.

METHODS

Forty patients with abdominal aortic aneurysm who were scheduled to undergo EVAR were enrolled in the study. There were 35 men and five women (mean age, 77.9 years). All patients had both iodinated contrast conventional DSA (C-DSA) and CO2-DSA immediately after EVAR. The sensitivity and specificity were calculated for the ability of CO2-DSA to detect ELs. We also correlated with computed tomography findings 6 months after EVAR.

RESULTS

C-DSA showed that 27 of the 40 patients (68%) had 28 ELs (type I, four; type II, 20; type III, three; type IV, one). CO2-DSA showed that 16 of the 40 patients (40%) had 17 ELs (type I, four; type II, 10; type III, three; type IV, none). For the prediction of direct ELs (type I and type III) with use of C-DSA as the criterion standard, CO2-DSA has a sensitivity of 1.0 and a specificity of 1.0. For the detection of persistent type II ELs (n = 11) with use of computed tomography findings 6 months from EVAR as the criterion standard, CO2-DSA has a sensitivity of 0.87 and a specificity of 0.97. C-DSA has a sensitivity of 0.82 and a specificity of 0.64.

CONCLUSIONS

CO2-DSA is reliable for the detection of direct ELs and persistent type II ELs in EVAR. CO2-DSA can be an option to detect ELs in the EVAR procedure.

Superior vena cava stenting guided by alternative imaging modalities in a patient with severe contrast allergy: a case report and brief literature review

Major adverse reactions to iodinated radiocontrast media are an uncommon but serious complication of cardiac catheterizations. We present a case of a 52-year-old woman with a sinus venosus atrial septal defect and partial anomalous pulmonary venous connection status post repair who presented with superior vena cava graft obstruction. Two overlapping stents were placed within the superior vena cava using gadolinium, CO2 angiography and transesophageal echocardiography for visualization of the graft stenoses. No iodinated media were used.

A prospective study of carbon dioxide digital subtraction versus standard contrast arteriography in the detection of endoleaks in endovascular abdominal aortic aneurysm repairs

BACKGROUND

The objective of this study is to compare intraoperative endoleak detection by carbon dioxide digital subtraction angiography (CO(2)-DSA) during endovascular aortic aneurysm repair (EVAR) with standard iodinated contrast angiography (ICA).

METHODS

Between 2006 and 2010, 76 patients with abdominal aortic aneurysms undergoing EVAR were enrolled in a prospective study. After EVAR, both an ICA and CO(2)-DSA completion study were performed. Two blinded vascular surgeons who were not involved with the EVAR separately interpreted the ICA and CO(2)-DSA results for the presence or absence of an endoleak. Identified endoleaks were classified by types. A third, "tie-breaker" blinded observer was used to resolve differences in interpretations. The sensitivity, specificity, negative predictive value, and positive predictive value were calculated for the ability of CO(2)-DSA to detect endoleaks. Cohen's κ statistic was used to assess interobserver agreement between the 2 initial interpreting surgeons.

RESULTS

Of the 76 patients undergoing EVAR, 66 were men with average age of 76 years, a mean aneurysm size of 5.8 cm (range, 4-10 cm), and creatinine of 1 (standard deviation, 0.33). ICA identified 35 type I and 15 type II endoleaks, respectively, while CO(2)-DSA identified 40 type I and 10 type II endoleaks. Overall, CO(2)-DSA had a sensitivity of 0.84, specificity of 0.72, positive predictive value of 0.86, and negative predictive value of 0.69 of intraoperative endoleak detection, with respect to ICA as the criterion standard. The interobserver κ between surgeons for ICA was 0.56, for detection of any endoleak or type I endoleak with CO(2)-DSA was 0.58, and for detection of type II endoleak with CO(2)-DSA was 0.29.

CONCLUSIONS

Interobserver agreement for the detection of endoleaks is superior with ICA compared to CO(2)-DSA. However, the sensitivity for detecting any endoleak and both the sensitivity and specificity for detecting type I endoleaks using CO(2)-DSA are acceptable. For detecting type II endoleaks using CO(2)-DSA, the sensitivity and positive predictive value are poor. Compared to ICA, CO(2)-DSA provides adequate images for endoleak detection during EVAR and is an acceptable alternative to ICA in patients at risk for contrast-related nephrotoxicity.