Feasibility and impact of carbon dioxide angiography on acute kidney injury following endovascular interventions in patients with peripheral artery disease and renal impairment

Renal denervation in the management of hypertension

Arterial hypertension is a global leading cause of cardiovascular, cerebrovascular, and renal disease, as well as mortality. Although pharmacotherapy is safe and effective in lowering blood pressure (BP) and cardiovascular disease risk, BP control remains poor, and the mortality rates associated with high BP have been steadily increasing. Device-based therapies have been investigated to overcome barriers to pharmacotherapy, including non-adherence and low rates of persistence to daily medications. Among these device-based therapies, catheter-based renal denervation (RDN) has been most extensively examined over the past 15 years. In this state-of-the-art article, we summarise the rationale for RDN, review the available evidence, provide recommendations for a safe procedure, and discuss the role of RDN in current guidelines and clinical practice.

Carbon dioxide angiography during peripheral vascular interventions is associated with decreased cardiac and renal complications in patients with chronic kidney disease

OBJECTIVE

Patients with chronic kidney disease (CKD) who undergo peripheral vascular interventions (PVI) with iodinated contrast are at higher risk of post-contrast acute kidney injury (PC-AKI). Carbon dioxide (CO2) angiography can reduce iodinated contrast volume usage in this patient population, but its impact on PC-AKI has not been studied. We hypothesize that CO2 angiography is associated with a decrease in PC-AKI in patients with advanced CKD.

METHODS

The Vascular Quality Initiative PVI dataset from 2010 to 2021 was reviewed. Only patients with advanced CKD (estimated glomular filtration rate <45 ml/min/1.73 m2) treated for peripheral arterial disease were included. Propensity matching and multivariate logistic regression based on demographics, comorbidities, CKD stage, and indications were used to compare the outcomes of patients treated with and without CO2.

RESULTS

There were 20,706 PVIs performed in patients with advanced CKD, and only 22% utilized CO2 angiography. Compared with patients treated without CO2, patients who underwent CO2 angiography were younger and less likely to be women or White, and more likely to have poor renal function, diabetes, cardiac comorbidities, and present with tissue loss. Propensity matching yielded well-matched groups with 4472 patients in each group. The procedural details after matching demonstrated 50% reduction in the volume of contrast used (32±33 vs 65±48 mL; P < .01). PVI with CO2 angiography was associated with lower rates of PC-AKI (3.9% vs 4.8%; P = .03) and cardiac complications (2.1% vs 2.9%; P = .03) without a significant difference in technical failure or major/minor amputations. Low contrast volumes (≤50 mL for CKD3, ≤20 mL for CKD4, and ≤9 mL for CKD5) are associated with reduced risk of PC-AKI (hazard ratio, 0.59; P < .01).

CONCLUSIONS

CO2 angiography reduces iodinated contrast volume usage during PVI and is associated with decreased cardiac complications and PC-AKI. CO2 angiography is underutilized and should be considered for patients with advanced CKD who require endovascular therapy.

Total iodine contrast-free strategy for the endovascular management of abdominal aortic aneurysms in chronic kidney disease patients: a pilot study

OBJECTIVES

To retrospectively evaluate the feasibility and effectiveness of the endovascular treatment of patients with abdominal aortic aneurysm (AAA) and chronic kidney disease (CKD) without the need for using iodinated contrast media (ICM) throughout the diagnostic, therapeutic and follow-up pathway.

METHODS

A retrospective review of prospectively collected data concerning 251 consecutive patients presenting an abdominal aortic or aorto-iliac aneurysm who underwent endovascular aneurysm repair (EVAR) from January 2019 to November 2022 at our academic institution was performed in order to identify patients with feasible anatomy with respect to manufacturers' instructions for use (IFU) and with CKD. Patients whose preoperative workout included duplex ultrasound (DUS) and plain computed tomography (pCT) for pre-procedural planning were extracted from a dedicated EVAR database. EVAR was performed with the use of carbon dioxide (CO₂) as contrast media of choice, whereas follow-up examinations consisted of either DUS, pCT or contrast-enhanced ultrasound (CEUS). Primary endpoints were technical success, perioperative mortality and early renal function variations. Secondary endpoints were all-type endoleaks (EL) and reinterventions, mid-term aneurysm-related and kidney-related mortality.

RESULTS

Forty-five patients had CKD and were treated electively (45/251, 17.9%). Of them, seventeen patients were managed with a total ICM-free strategy and constituted the object of the present study (17/45, 37.8%; 17/251, 6.8%). In seven cases an adjunctive planned procedure was performed (7/17, 41.2%). No intraoperative bail-out procedures were needed. This extracted cohort of patients presented similar mean preoperative and postoperative (at discharge) GFRs values, 28.14 (SD 13.09; median 28.06, IQR 20.25) ml/min/1.73m² and 29.33 (SD 14.61; median 27.35, IQR 22) ml/min/1.73m² respectively (p= .210). Mean follow-up was 16.4 months (SD 11.89; median 18, IQR 23). During follow-up no graft-related complications occurred in terms of either thrombosis, type I or III EL, aneurysm rupture or conversion. The mean GFR at follow-up was 30.39 ml/min/1.73m² (SD 14.45; median 30.75, IQR 21.93), with no significant worsening in comparison with pre and postoperative values (p= .327 and p= .856 respectively). No aneurysm- or kidney-related deaths occurred during follow-up.

CONCLUSIONS

Our initial experience shows that total iodine contrast-free AAA endovascular management in patients with CKD may be feasible and safe. Such an approach seems to guarantee the preservation of residual kidney function without increasing the risks of aneurysm-related complication in the early and midterm postoperative period and it could be considered even in case of complex endovascular procedures.

Contrast-induced acute kidney injury and its contemporary prevention

The complexity and application range of interventional and diagnostic procedures using contrast media (CM) have recently increased. This allows more patients to undergo procedures that involve CM administration. However, the intrinsic CM toxicity leads to the risk of contrast-induced acute kidney injury (CI-AKI). At present, effective therapy of CI-AKI is rather limited. Effective prevention of CI-AKI therefore becomes crucially important. This review presents an in-depth discussion of CI-AKI incidence, pathogenesis, risk prediction, current preventive strategies, and novel treatment possibilities. The review also discusses the difference between CI-AKI incidence following intraarterial and intravenous CM administration. Factors contributing to the development of CI-AKI are considered in conjunction with the mechanism of acute kidney damage. The need for ultimate risk estimation and the prediction of CI-AKI is stressed. Possibilities of CI-AKI prevention is evaluated within the spectrum of existing preventive measures aimed at reducing kidney injury. In particular, the review discusses intravenous hydration regimes and pre-treatment with statins and N-acetylcysteine. The review further focuses on emerging alternative imaging technologies, alternative intravascular diagnostic and interventional procedures, and new methods for intravenous hydration guidance; it discusses the applicability of those techniques in complex procedures and their feasibility in current practise. We put emphasis on contemporary interventional cardiology imaging methods, with a brief discussion of CI-AKI in non-vascular and non-cardiologic imaging and interventional studies.

Risk of Contrast-Associated Acute Kidney Injury in Patients Undergoing Peripheral Angiography with Carbon Dioxide Compared to Iodine-Containing Contrast Agents: A Systematic Review and Meta-Analysis

The aim of this systematic review was to summarise the comparative evidence on the risk of contrast-associated acute kidney injury (CA-AKI) with CO₂ or iodinated contrast medium (ICM) for peripheral vascular interventions. We searched Ovid MEDLINE, Cochrane Library, Embase, Epistemonikos, PubMed-similar-articles, clinical trial registries, journal websites, and reference lists up to February 2022. We included studies comparing the risk of CA-AKI in patients who received CO₂ or ICM for peripheral angiography with or without endovascular intervention. Two reviewers screened the references and assessed the risk of bias of the included studies. We extracted data on study population, interventions and outcomes. For the risk of CA-AKI as our primary outcome of interest, we calculated risk ratios (RRs) with a 95% confidence interval (CI) and performed random-effects meta-analyses. We identified three RCTs and five cohort studies that fully met our eligibility criteria. Based on a random-effects meta-analysis, the risk of CA-AKI was lower with CO₂ compared to ICM (8.6% vs. 15.2%; RR, 0.59; 95% CI 0.33-1.04). Only limited results from a few studies were available on procedure and fluoroscopy time, radiation dose and CO₂-related adverse events. The evidence suggests that the use of CO₂ for peripheral vascular interventions reduces the risk of CA-AKI compared to ICM. However, due to the relevant residual risk of CA-AKI with the use of CO₂, other AKI risk factors must be considered in patients undergoing peripheral vascular interventions.

Emergency angiography for trauma patients and potential association with acute kidney injury

BACKGROUND

Angiography has been conducted as a hemostatic procedure for trauma patients. While several complications, such as tissue necrosis after embolization, have been reported, little is known regarding subsequent acute kidney injury (AKI) due to contrast media. To elucidate whether emergency angiography would introduce kidney dysfunction in trauma victims, we compared the incidence of AKI between patients who underwent emergency angiography and those who did not.

METHODS

A retrospective cohort study was conducted using a nationwide trauma database (2004-2019), and adult trauma patients were included. The indication of emergency angiography was determined by both trauma surgeons and radiologists, and AKI was diagnosed by treating physicians based on a rise in serum creatinine and/or fall in urine output according to any published standard criteria. Incidence of AKI was compared between patients who underwent emergency angiography and those who did not. Propensity score matching was conducted to adjust baseline characteristics including age, comorbidities, mechanism of injury, vital signs on admission, Injury Severity Scale (ISS), degree of traumatic kidney injury, surgical procedures, and surgery on the kidney, such as nephrectomy and nephrorrhaphy.

RESULTS

Among 230,776 patients eligible for the study, 14,180 underwent emergency angiography. The abdomen/pelvis was major site for angiography (10,624 [83.5%]). Embolization was performed in 5,541 (43.5%). Propensity score matching selected 12,724 pairs of severely injured patients (median age, 59; median ISS, 25). While the incidence of AKI was rare, it was higher among patients who underwent emergency angiography than in those who did not (140 [1.1%] vs. 67 [0.5%]; odds ratio = 2.10 [1.57-2.82]; p < 0.01). The association between emergency angiography and subsequent AKI was observed regardless of vasopressor usage or injury severity in subgroup analyses.

CONCLUSIONS

Emergency angiography in trauma patients was probably associated with increased incidence of AKI. The results should be validated in future studies.

Contrast-induced nephropathy in non-cardiac vascular procedures, a narrative review: Part 2

This is Part 2 of a narrative review summarizing the literature on CIN after non-cardiac vascular diagnostic or therapeutic procedures, focusing on peripheral artery disease (PAD) and renal artery stenosis (RAS). Part 1 discussed CIN in relation to aortic aneurysms and carotid stenosis. We comment on the incidence, biomarkers, risk factors, and consequences of CIN in patients with PAD or RAS, as well as on strategies to prevent CIN. Future perspectives in the field of CIN in relation to non-cardiac vascular procedures are also considered.