The challenge of diagnosing atheroembolic renal disease: clinical features and prognostic factors

Management of Systemic Inflammatory Response Syndrome After Cardiovascular Interventions. Diagnostic, Prognostic, and Therapeutic Implications

A substantial number of patients may experience systemic inflammatory response syndrome (SIRS) and related adverse events after transcatheter aortic valve implantation and endovascular aortic aneurysm repair. Although a clear etiology has not been established, endothelial disruption and tissue-ischemic response secondary to the foreign material may represent the trigger events. A latency period (0 to 48 hours) may occur between the initial injury and onset of symptoms mirroring an initial local response followed by a systemic response. Clinical presentation can be mild or severe depending on external triggers and characteristics of the patient. Diagnosis is challenging because it simulates an infection, but lack of response to antibiotics, negative cultures are supportive of SIRS. Increased in-hospital stay, readmissions, major cardiovascular events, and reduced durability of the device used are the main complications. Treatment includes non-steroidal anti-inflammatory drugs or corticosteroids. In conclusion, further studies are warranted to fully explore pathophysiologic mechanisms underpinning SIRS and the possibility of enhancing device material immune compatibility to reduce the inflammatory reaction of the host tissue.

Acute Kidney Injury Management Strategies Peri-Cardiovascular Interventions

In many countries, the aging population and the higher incidence of comorbid conditions have resulted in an ever-growing need for cardiac interventions. Acute kidney injury (AKI) is a common complication of these interventions, associated with higher mortalities, chronic or end-stage kidney disease, readmission rates, and hospital and post-discharge costs. The AKI pathophysiology includes contrast-associated AKI, hemodynamic changes, cardiorenal syndrome, and atheroembolism. Preventive measures include limiting contrast media dose, optimizing hemodynamic conditions, and limiting exposure to other nephrotoxins. This review article outlines the current state-of-art knowledge regarding AKI pathophysiology, risk factors, preventive measures, and management strategies in the peri-interventional period.

A Massive Renal Infarction Due to Atheroemboli: A Case Report

The symptoms of acute renal infarction (ARI) caused by atheroemboli are vague, making it rare. Early diagnosis of renal infarction can be made through contrast-enhanced CT of the abdomen. However, diagnosing atheroemboli is more challenging. Kidney biopsy is the most accurate method to determine the cause, but it may not always be available in clinical settings. In cases where a thrombectomy is performed, white substances in thrombus aspiration or the patient's blood can suggest a diagnosis. Intervention is an effective technique, but there is controversy due to a lack of data, particularly in lobular artery infarction. We successfully treated one case using thrombus aspiration, and the specimens suggested atherosclerosis as the cause.

Supra-renal aortic atheroma extent and composition predict acute kidney injury after transcatheter aortic valve replacement: A three-dimensional computed tomography study

OBJECTIVE

Acute kidney injury (AKI) may complicate transcatheter aortic valve replacement (TAVR) and could be linked to atheroembolization associated with catheter manipulation in the supra-renal (SR) aorta. We sought to determine the impact of SR aortic atheroma burden (SR-AAB) and composition, as well as of the aortic valve calcium score (AV-CS), measured at pre-operative multislice computed tomography (PO-MSCT), on AKI-TAVR.

METHODS

All TAVR-patients 3 January-2018 to December-2020 were included. A three-dimensional analysis of PO-MSCT was performed, calculating percentage SR-AAB (%SR-AAB) as [(absolute SR-AAB volume)*100/vessel volume]. Types of plaque were defined according to Hounsfield unit (HU) intensity ranges. Calcified plaque was subcategorized into 3 strata: low- (351-700 HU), mid- (701-1000 HU), and high‑calcium (>1000 HU, termed 1 K-plaque).

RESULTS

The study population included 222 patients [mean age 83.3 ± 5.7 years, 95 (42.8%) males], AKI-TAVR occurred in 67/222 (30.2%). Absolute SR-AAB (41.3 ± 16.4 cm³ vs. 32.5 ± 10.7 cm³,p < 0.001) and %SR-AAB (17.6 ± 5.1% vs. 13.9 ± 4.3%,p < 0.001) were significantly higher in patients developing AKI-TAVR. Patients who developed AKI-TAVR had higher mid‑calcium (6.9 ± 3.8% vs. 4.2 ± 3.5%,p < 0.001) and 1 K-plaque (5.4 ± 3.7% vs. 2.4 ± 2.4%,p < 0.001) with no difference in AV-CS (p = 0.691). Adjusted multivariable logistic regression analysis showed that %SR-AAB [OR (x%increase): 1.12, 95%CI: 1.04-1.22,p = 0.006] and %SR-calcified plaque [OR (x%increase): 5.60, 95%CI: 2.50-13.36,p < 0.001] were associated with AKI-TAVR. Finally, 3-knots spline analyses identified %SR-AAB >15.0% and %SR-calcified plaque >7.0% as optimal thresholds to predict an increased risk of AKI-TAVR.

CONCLUSIONS

Suprarenal aortic atheroma, when highly calcified, is associated with AKI-TAVR. Perioperative-MSCT assessment of aortic atherosclerosis may help in identification of patients at high-risk for AKI-TAVR, who could benefit from higher peri-operative surveillance.

Association of Radial Artery Access with Reduced Incidence of Acute Kidney Injury

Objectives

To determine if radial artery (RA) access compared with femoral artery (FA) access for percutaneous coronary intervention (PCI) is associated with a lower incidence of acute kidney injury (AKI).

Background

AKI results in substantial morbidity and cost following PCI. Prior studies comparing the occurrence of AKI associated with radial artery (RA) versus femoral artery (FA) access have mixed results.

Methods

Using a large state-wide database, 14,077 patients (8,539 with RA and 5,538 patents with FA access) were retrospectively compared to assess the occurrence of AKI following PCI. To reduce selection bias and balance clinical data across the two groups, a novel machine learning method called a Generalized Boosted Model was conducted on the arterial access site generating a weighted propensity score for each variable. A logistic regression analysis was then performed on the occurrence of AKI following PCI using the weighted propensity scores from the Generalized Boosted Model.

Results

As shown in other studies, multiple variables were associated with an increase in AKI after PCI. Only RA access (OR 0.82; 95% CI 0.74-0.91) and male gender (OR 0.80; 95% CI 0.72-0.89) were associated with a lower occurrence of AKI. Based on the calculated Mehran scores, patients were stratified into groups with an increasing risk of AKI. RA access was consistently found to have a lower risk of AKI compared with FA access across these groups of increasing risk.

Conclusions

Compared with FA access, RA access is associated with an 18% lower rate of AKI following PCI. This effect was observed among different levels of risk for developing AKI. Although developed from a retrospective analysis, this study supports the use of RA access when technically possible in a diverse group of patients.

Optimizing the Outcomes of Percutaneous Coronary Intervention in Patients with Chronic Kidney Disease

Percutaneous coronary intervention (PCI) is one of the most common procedures performed in medicine. However, its net benefit among patients with chronic kidney disease (CKD) is less well established than in the general population. The prevalence of patients suffering from both CAD and CKD is high, and is likely to increase in the coming years. Planning the adequate management of this group of patients is crucial to improve their outcome after PCI. This starts with proper preparation before the procedure, the use of all available means to reduce contrast during the procedure, and the implementation of modern strategies such as radial access and drug-eluting stents. At the end of the procedure, personalized antithrombotic therapy for the patient’s specific characteristics is advisable to account for the elevated ischemic and bleeding risk of these patients.

Outcomes of patients with Cholesterol crystal embolism treated by peritoneal dialysis: retrospective study from the RDPLF registry

Cholesterol crystal embolisms disease (CED) is a systemic disease characterized by tissue ischemia and microinflammation related to occlusion of arterioles by microemboli from ulcerated atheromatous plaques. The kidney is one of the most affected organs, often requiring dialysis. Our study examines the outcomes of a cohort of patients with CED treated with peritoneal dialysis (PD). As anticoagulants can favor emboli, peritoneal dialysis may theoretically have an advantage. From the database of the French Language Peritoneal Dialysis Registry (RDPLF), between January 1, 1995, and December 31, 2021, we selected patients treated with PD for >90 days and with an age >18 years. On the basis of the variables of patient autonomy, diabetes, BMI, modified Charlson index, age, sex, pre-PD treatment, causes of death, causes of transfer to hemodialysis, and peritonitis, three types of survival were estimated (patient, technical, and composite). After adjustment by propensity scores and taking into account competitive risks, 2 groups of patients were constituted on the basis of baseline nephropathy: emboli group vs. control group. Patient survival and strict technical survival are not associated with the type of nephropathy (CED versus others). Composite technical survival (uncensored for deaths and transfers to hemodialysis) was only associated with cholesterol emboli nephropathy in the multivariate analysis adjusted for diabetes, autonomy, and age of the patient at the start of the dialysis treatment (p=0.011; 95% CI [0.736 [0.581-0.931]]). Our study from the RDPLF database shows no difference in technical and patient survival in a cohort of patients with CED vs. a control group. It also confirms that PD may represent an adequate choice in this pathology.

Incidence, Risk Factors, and Prognosis of Cholesterol Crystal Embolism Because of Percutaneous Coronary Intervention

Cholesterol crystal embolism (CCE) is a rare but serious complication of percutaneous coronary intervention (PCI). However, its incidence, risk factors, and prognosis in the contemporary era are not well known. We included 23,184 patients who underwent PCI in our institution between January 2000 and December 2019 in this study. The diagnosis of CCE was made histologically or by the combination of cutaneous signs and specific blood test results. In patients with CCE, we evaluated the incidence, risk factors, and prognosis. A total of 88 patients (0.38%) were diagnosed with CCE. The incidence of CCE seemed to decline through the investigated 20 years. Positive predictors of CCE were age ≥70 years (68% vs 59%, p = 0.012), aortic aneurysm (23% vs 7.2% p <0.001), and a femoral approach (71% vs 45%, p <0.001), whereas a negative predictor of CCE was the use of an inner sheath (63% vs 77%, p <0.001). The rate of 1-year mortality and the requirement for chronic hemodialysis within 1 year after PCI in patients with CCE were 10% and 11%, respectively. The use of an inner sheath and a nonfemoral approach was associated with a lower incidence of CCE. In conclusion, because the prognosis of patients with CCE is still poor, preprocedural identification of high-risk patients and selection of low-risk procedures could be important for preventing CCE.

Statin Use Influence on the Occurrence of Acute Kidney Injury in Patients with Peripheral Arterial Disease

AIM

Acute kidney injury (AKI) is an important clinical issue in the diagnosis and treatment of cardiovascular diseases. The association between pretreatment by statins and the occurrence of AKI in patients with peripheral arterial diseases (PAD) remains unclear. Therefore, we examined the association between statin therapy and the occurrence of AKI in patients with PAD.

METHODS

We retrospectively analyzed data from the endovascular treatment (EVT) database in our hospital. A total of 295 patients who underwent angiography and/or intervention for PAD between October 2011 and March 2016 were enrolled and divided into two groups: those without statins (control group; N=157) and those with statins (statin group; N=138) for at least 1 month before admission. We examined the occurrence of AKI and its related factors in these patients.

RESULTS

The serum creatinine levels, dose of contrast medium, use of a renin-angiotensin system inhibitor, smoking habit, and blood pressure were similar in both groups. The statin group had more diabetes patients, had patients who were significantly younger, had patients with a higher body mass index (BMI), and had patients with lower low-density lipoprotein cholesterol than the control group. With regard to the occurrence of AKI, there was a significantly lower incidence in the statin group compared with the control group (5% vs. 16%, p＜0.05). The result of the multivariate analysis indicated that statin therapy was significantly correlated with lower occurrence rates of AKI (p＜0.05).

CONCLUSIONS

Our study suggests that statin therapy might prevent the occurrence of AKI after angiography and/or intervention for PAD.

Cholesterol crystal embolism-related cerebral infarction: Magnetic resonance imaging and clinical characteristics

Background and aims

Cholesterol crystal embolism-related cerebral infarction (CCE-CI) is frequently misdiagnosed due to the lack of specific symptoms. To aid in differential diagnosis, this study comprehensively characterized the magnetic resonance imaging (MRI) and clinical manifestations of CCE-CI and compared these features to those of atherothrombotic cerebral infarction (ACI).

Methods

This single-center, retrospective, observational study was conducted at Kitasato University Hospital, Kanagawa, Japan. We identified 37 clinically or histopathologically confirmed CCE-CI cases and 110 ACI cases treated from January 2006 to May 2020. Groups were compared for mean age, sex ratio, clinical presentations, imaging manifestations, precipitating factors, comorbid conditions, medications, and smoking history.

Results

Of 37 eligible patients with CCE-CI, 10 (27.0%) received brain MRI, of which 8 (21.6%) exhibited high-intensity signals indicative of brain lesions on diffusion-weighted imaging (DWI). However, two patients with DWI lesions exhibited no detectable neurological abnormalities. Patients with CCE-CI frequently demonstrated bilateral DWI lesions involving the bilateral anterior and posterior circulation, a pattern absent in ACI (50% vs. 0%, p < 0.001). Compared to patients with ACI, CCE-CI patients also demonstrated significantly lower estimated glomerular filtration rate (p < 0.001) as well as more frequent eosinophilia (p = 0.006), atherosclerotic plaques ≥4-mm thick in the ascending aorta or proximal arch (p = 0.001), and aortic aneurysm (p < 0.001).

Conclusions

Patients with CCE-CI develop multiple DWI lesions across several vascular territories, even in the absence of neurological symptoms. Comorbid aortic aneurysm may increase CCE-CI risk. These findings could help in the differential diagnosis of CCE-CI.

•

Diagnosis of CCE-CI is challenging due to nonspecific neurological symptoms.

•

Brain DWI revealed multiple small ischemic lesions among patients with CCE-CI.

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CCE-CI was associated with atherosclerotic plaques in the ascending aorta and arch.

•

CCE-CI was also associated with lower eGFR and higher blood eosinophil count.

•

CCE-CI is associated with aortic aneurysm morbidity.

Burden of kidney failure from atheroembolic disease and association with survival in people receiving dialysis in Australia and New Zealand: a multi-centre registry study

Background

Cardiovascular disease is a leading cause of mortality in kidney failure (KF). Patients with KF from atheroembolic disease are at higher risk of cardiovascular disease than other causes of KF. This study aimed to determine survival on dialysis for patients with KF from atheroembolic disease compared with other causes of KF.

Methods

All adults (≥ 18 years) with KF initiating dialysis as the first kidney replacement therapy between 1 January 1990 and 31 December 2017 according to the Australia and New Zealand Dialysis and Transplant registry were included. Patients were grouped into either: KF from atheroembolic disease and all other causes of KF. Survival outcomes were assessed by the Kaplan-Meier method and Cox regression analysis adjusted for patient-related characteristics.

Results

Among 65,266 people on dialysis during the study period, 334 (0.5%) patients had KF from atheroembolic disease. A decreasing annual incidence of KF from atheroembolic disease was observed from 2008 onwards. Individuals with KF from atheroembolic disease demonstrated worse survival on dialysis compared to those with other causes of KF (HR 1.80, 95% confidence interval [CI] 1.61–2.03). The respective one- and five-year survival rates were 77 and 23% for KF from atheroembolic disease and 88 and 47% for other causes of KF. After adjustment for patient characteristics, KF from atheroembolic disease was not associated with increased patient mortality (adjusted HR 0.93 95% CI 0.82–1.05).

Conclusions

Survival outcomes on dialysis are worse for individuals with KF from atheroembolic disease compared to those with other causes of KF, probably due to patient demographics and higher comorbidity.

Formation and Cellular Impact of Cholesterol Crystals in Health and Disease

Cholesterol crystals (CCs) were first discovered in atherosclerotic plaque tissue in the early 1900 and have since been observed and implicated in many diseases and conditions, including myocardial infarction, abdominal aortic aneurism, kidney disease, ocular diseases, and even central nervous system anomalies. Despite the widespread involvement of CCs in many pathologies, the mechanisms involved in their formation and their role in various diseases are still not fully understood. Current knowledge concerning the formation of CCs, as well as the molecular pathways activated upon cellular exposure to CCs, will be explored in this review. As CC formation is tightly associated with lipid metabolism, the role of cellular lipid homeostasis in the formation of CCs is highlighted, including the role of lysosomes. In addition, cellular pathways and processes known to be affected by CCs are described. In particular, CC-induced activation of the inflammasome and production of reactive oxygen species, along with the role of CCs in complement-mediated inflammation is discussed. Moreover, the clinical manifestation of embolized CCs is described with a focus on renal and skin diseases associated with CC embolism. Lastly, potential therapeutic measures that target either the formation of CCs or their impact on different cell types and tissues are highlighted.

An Unusual Presentation of Cholesterol Embolization Syndrome

Cholesterol embolization syndrome (CES) is a rare presentation of systemic atherosclerosis, which commonly presents in patients with risk factors of coronary artery disease and usually occurs after cardiac or vascular procedures. Laboratory tests are nonspecific, and imaging studies may visualize the plaque. Management includes supportive care directed to relieve the end-organ damage. The prognosis of CES is poor, with high mortality of up to 29% if the CES resulted in atheroembolic renal disease (AERD). In our report, we present a 90-year-old Caucasian female who was diagnosed with CES and complicated with AERD. The patient did not undergo any cardiac or vascular procedures. This case highlights the importance of considering CES and AERD as a potential cause of renal failure, especially in high-risk patients, even if the patients did not have any history of cardiac or vascular intervention.

Acute kidney injury in patients with acute coronary syndrome undergoing invasive management treated with bivalirudin vs. unfractionated heparin: insights from the MATRIX trial

AIMS

Acute kidney injury (AKI) is a critical complication among patients with acute coronary syndrome (ACS) undergoing invasive management. The value of adjunctive antithrombotic strategies, such as bivalirudin or unfractionated heparin (UFH) on the risk of AKI is unclear.

METHODS AND RESULTS

Among 7213 patients enrolled in the MATRIX-Antithrombin and Treatment Duration study, 128 subjects were excluded due to incomplete information on serum creatinine (sCr) or end-stage renal disease on dialysis treatment. The primary endpoint was AKI defined as an absolute (>0.5 mg/dL) or a relative (>25%) increase in sCr. AKI occurred in 601 patients (16.9%) treated with bivalirudin and 616 patients (17.4%) treated with UFH [odds ratio (OR): 0.97; 95% confidence interval (CI): 0.85-1.09; P = 0.58]. A >25% sCr increase was observed in 597 patients (16.8%) with bivalirudin and 616 patients (17.4%) with UFH (OR: 0.96; 95% CI: 0.85-1.08; P = 0.50), whereas a >0.5 mg/dL absolute sCr increase occurred in 176 patients (5.0%) with bivalirudin vs. 189 patients (5.4%) with UFH (OR: 0.92; 95% CI: 0.75-1.14; P = 0.46). By implementing the Kidney Disease Improving Global Outcomes (KDIGO) criteria, the risk of AKI was not significantly different between bivalirudin and UFH groups (OR: 0.88; 95% CI: 0.72-1.07; P = 0.21). Subgroup analyses of the primary endpoint suggested a benefit with bivalirudin in patients randomized to femoral access.

CONCLUSION

Among ACS patients undergoing invasive management, the risk of AKI was not significantly lower with bivalirudin compared with UFH.

TRIAL REGISTRATION

clinicaltrials.gov NCT01433627.

Acute Kidney Injury Following Percutaneous Coronary Intervention for Acute Coronary Syndrome: Incidence, Aetiology, Risk Factors and Outcomes

We investigated the predictors, aetiology and long-term outcomes of acute kidney injury (AKI) following urgent percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). Acute kidney injury occurred in 198 (7.2%) of 2917 patients: 14.1% of AKI cases were attributed to cardiogenic shock and 5.1% were classified as atheroembolic renal disease (AERD). Significant risk factors for AKI included age (odds ratio [OR] 1.05, 95% confidence limits [CI] 1.03-1.06), diabetes (OR 1.73, 95% CI 1.20-2.47), hypertension (OR 1.43, 95% CI 1.03-2.00), heart failure (OR 3.01, 95% CI 1.58-5.57), femoral access (OR 1.50, 95% CI 1.03-2.15), cardiogenic shock (OR 2.03, 95% CI 1.19-3.37) and ST-elevation myocardial infarction (STEMI) (OR 3.89, 95% CI 2.80-5.47). One-year mortality after AERD was 44.4% and renal replacement therapy (RRT) requirement 22.2% (compared with mortality 33.3% and RRT requirement 7.4%, respectively, in all other AKI patients). Mortality at 1 year was associated with AKI (OR 4.33, 95% CI 2.89-6.43), age (OR 1.08, 95% CI 1.06-1.09), heart failure (OR 1.92, 95% CI 1.05-3.44), femoral access (OR 2.05, 95% CI 1.41-2.95) and cardiogenic shock (OR 3.63, 95% CI 2.26-5.77). Acute kidney injury after urgent PCI is strongly associated with worse outcomes. Atheroembolic renal disease has a poor outcome and a high likelihood of long-term RRT requirement.

Efficacy of LDL apheresis for the treatment of cholesterol crystal embolism: A prospective, controlled study

This study was performed to evaluate the efficacy and safety of LDL apheresis (LDL-A) for the treatment of cholesterol crystal embolism (CCE) after cardiovascular procedures. We conducted a prospective multicenter study of 34 patients with CCE and 15 historical control patients. The present participants underwent six sessions of LDL-A for 4 weeks and underwent medical therapy with corticosteroids and statins. The mean creatinine concentration and estimated glomerular filtration rate at baseline were 3.82 ± 2.29 mg/dL and 17.8 ± 9.9 mL/min/1.73 m² , respectively. The prevalence of maintenance dialysis at 24 weeks was significantly lower in the present participants than in the historical controls (3.1% vs. 40.0%, respectively; p < 0.0001), but the mortality rate at 24 weeks was comparable (19% vs. 33%, respectively). Although 45 adverse events occurred in 23 participants, there were no unexpected adverse events. LDL-A for CCE reduces the prevalence of maintenance dialysis 24 weeks later and is well tolerated. This study was registered in the Japan Registry of Clinical Trials (jRCTs022180029) and clinicaltrials.gov (NCT01726868).

Impact of radial access on contrast-induced acute kidney injury in patients with coronary artery bypass grafts

PURPOSE

We investigated the impact of radial access on contrast-induced acute kidney injury (CI-AKI) in patients with coronary artery bypass graft (CABG) undergoing cardiac catheterization.

METHODS

This retrospective monocenter study included 527 CABG patients undergoing cardiac catheterization via radial (58.1%, N = 306) or femoral access (41.9%, N = 221). Primary outcome measure was CI-AKI defined in accordance with the KDIGO criteria. Independent predictors for CI-AKI were assessed. 1-year mortality was assessed depending on the occurrence of CI-AKI.

RESULTS

In total, 99 CABG patients (18.8%) developed CI-AKI within 48 h after cardiac catheterization. Compared to patients without CI-AKI, amount of contrast media used (203.1 ± 102.6 ml vs. 204.2 ± 98.2 ml; P = 0.892) as well as procedural times (87.9 ± 44.8 vs. 79.8 ± 37.0; P = 0.190) were similarly. Regarding vascular access, there was no significant difference in the incidence of CI-AKI between radial and femoral approach (19.0% vs. 18.6%; p = 0.907). However, poor left ventricular ejection fraction (odds ratio [OR] = 1.72, P = 0.026), chronic kidney disease (OR = 2.30, P = 0.001) and acute coronary syndrome (OR = 1.64, P = 0.043) were independent predictors for CI-AKI. The occurrence of CI-AKI was significantly associated with an increased 1-year mortality (hazard ratio [HR] = 2.52, P = 0.003).

CONCLUSIONS

With 18.8%, CI-AKI is a frequent complication in CABG patients undergoing cardiac catheterization. Radial access did not decrease the risk when compared to the femoral approach.

Acute Kidney Injury After Repeated Exposure to Contrast Material for Coronary Angiography

Objective

To assess the incidence of contrast-associated acute kidney injury (CAAKI) after repeated exposure to contrast material for computed tomography (CT) and conventional coronary angiography within short intervals.

Methods

We studied 651 patients enrolled in the CorE-64 (November 5, 2005–January 30, 2007) and CORE320 (October 21, 2009–August 17, 2011) multicenter studies. Participants with suspected obstructive coronary heart disease were referred for diagnostic cardiac catheterization and underwent coronary CT angiography for research before invasive angiography. Nonionic, low-osmolality iodinated contrast material was used for all imaging.

Results

The median age of the patients was 62 years, and 190 (29%) were women. Major risk factors for acute kidney injury were present in 277 of 651 (43%) patients. The median interval between CT imaging and invasive angiography was 3.1 days (interquartile range, 0.9-8.0 days). The median volume of contrast material was 100 mL for each test. In 16 (2.5%) of 651 patients, CAAKI developed. Of these cases, 1 occurred after the CT scan, whereas 6 were documented after invasive angiography (compared with post-CT creatinine concentration assessment). In 9 patients, CAAKI was found in comparing creatinine concentration after completion of both tests with baseline values (but not compared with post-CT imaging).

Conclusion

Acute kidney injury after repeated exposure to iodinated contrast media within a few days is uncommon even in a population of patients with highly prevalent risk factors. Withholding of clinically indicated contrast-enhanced imaging may therefore not be justified in this setting.

Ischemic small bowel perforation caused by cholesterol crystal embolism following transcatheter arterial chemoembolization for recurrent hepatocellular carcinoma: a case report

Background

Cholesterol crystal embolism (CCE) following transcatheter arterial chemoembolization (TACE) is rare.

Case presentation

A 71-year-old man underwent TACE for recurrence of hepatocellular carcinoma (HCC). On postoperative day (POD) 5, he developed abdominal pain and fever. Computed tomography revealed intraperitoneal free air. The patient was diagnosed with gastrointestinal perforation with peritonitis, for which partial intestinal resection and covering ileostomy were performed. Histological examination revealed perforation of the small intestine caused by CCE. The patient made a satisfactory recovery and was discharged on POD 30. The patient showed no recurrence of cholesterol crystal embolism or HCC for 2 years after surgery.

Conclusion

We reported a successfully treated case of ischemic small bowel perforation due to cholesterol crystal embolism following transcatheter arterial chemoembolization for recurrent HCC.

Cholesterol embolization syndrome and intra-abdominal bleeding immediately after initiation of hemodialysis: a case report with literature review

Background

Cholesterol embolization syndrome (CES) is a disease associating with the systemic cholesterol crystal embolism and end-organ dysfunction due to the atherosclerotic plaque rupture, which is dominantly triggered by the intravascular intervention. There is no consensus for which types of anticoagulants we should use during the hemodialysis in patients with CES and end-stage renal disease.

Case presentation

We had a 68-year-old man with CES due to intravascular intervention, who suffered the omental bleeding, instead of the embolism, immediately after the initiation of hemodialysis with heparinization. An emergent laparotomy found active bleeding from the omentum, which was surgically repaired. The histopathological analysis showed the embolization of cholesterol crystal clefts in the omentum artery and the injury of arterial wall structure accompanied by the infiltration of inflammatory cells. We preferred nafamostat mesylate during hemodialysis and he had no adverse events following the surgery.

Conclusions

It should be noticed that, in addition to the embolic events, bleeding events can develop in patients with CES, particularly following the initiation of hemodialysis with anticoagulation therapy.

Comparison of acute kidney injury with radial vs. femoral access for patients undergoing coronary catheterization: An updated meta-analysis of 46,816 patients

Trans-radial access for percutaneous coronary intervention or angiography has gained popularity amongst interventional cardiologists. Radial access is also thought to reduce the incidence of acute kidney injury (AKI) in the immediate post-operative period. The purpose of the present study was to perform a comprehensive updated systematic review and meta-analysis comparing the incidence of AKI following the radial vs. femoral route of coronary catheterization. An electronic literature search of the PubMed, BioMed Central, Scopus, Cochrane Central Register of Controlled Trials and Google Scholar databases up to 1st January 2020 was performed. A total of 14 studies were included, 2 of which were randomized controlled trials (RCTs), and 6 studies utilized propensity score matching. Comparison of the data of 21,479 patients in the radial group and 25,337 patients in the femoral group indicated a reduced incidence of AKI with the radial route [odds ratio (OR):0.66, 95% CI: 0.54-0.81, P<0.0001, I²=74%]. Similar results were obtained with sub-group analyses for RCTs (OR: 0.87, 95% CI: 0.77-0.98, P=0.02, I²=0%), retrospective studies (OR: 0.57, 95% CI: 0.36-0.90, P=0.02, I²=86%) and propensity score-matched studies (OR: 0.63, 95% CI: 0.48-0.83, P=0.0009, I²=45%). Multivariable-adjusted ORs of AKI for the radial vs. femoral route were extracted from non-RCTs and pooled for a meta-analysis, which also demonstrated similar results (OR: 0.70, 95% CI: 0.57-0.88, P=0.002, I²=70%). Within the limitations of the study, the present results indicate that, as compared to femoral access, the use of trans-radial access for coronary catheterization is associated with a significantly reduced incidence of AKI. A reduction of AKI by ~34% may be expected with the use of radial access.

Proportion and risk factors of cholesterol crystal embolization after cardiovascular procedures: a retrospective national database study

Cholesterol crystal embolization (CCE) is a rare, mainly iatrogenic condition. The proportion of CCE after cardiovascular procedures has not been fully elucidated. The purpose of this study was to determine the proportion of CCE diagnosed after cardiovascular procedures and to identify risk factors for CCE occurrence. Data on patients aged older than 40 years who underwent cardiovascular procedures between July 2010 and March 2017 were extracted from the Japanese Diagnosis Procedure Combination database. Inpatients diagnosed with CCE within 1 year after procedures in the same hospital were identified. Logistic regression analysis was performed to identify factors associated with the occurrence of CCE. There were 962 patients with CCE in 2,190,300 patients who underwent cardiovascular procedures. The overall proportion of CCE after cardiovascular procedures was 4.4 per 10,000 patients (95% confidence interval 4.1-4.7). The overall in-hospital mortality among patients with CCE was 11% (107/962). Older age, male sex, smoking, heart failure, peripheral vascular disease, cerebrovascular disease, renal insufficiency, diabetes mellitus, hypertension, and aortic aneurism and dissection were significantly associated with the higher occurrence of CCE. Compared with cardioangiography, several procedures were significantly associated with higher occurrence of CCE, including intra-aortic balloon pumping, percutaneous transluminal angioplasty of the renal artery, and transcatheter aortic valve implantation or balloon aortic valvuloplasty. CCE is rare but remains a severe complication of cardiovascular procedures. Atherosclerotic risk factors and certain cardiovascular procedures were associated with CCE.

Association between eosinophilia and renal prognosis in patients with pathologically proven cholesterol crystal embolism

Background

Approximately, 20–70% of patients with cholesterol crystal embolism (CCE) have eosinophilia. However, it remains unknown how eosinophilia influences renal prognosis in patients with CCE. In this study, we investigated the association between eosinophil count (Eo) and renal prognosis in CCE patients on steroid therapy.

Methods

The present study is a single-centered retrospective cohort study in patients with renal dysfunction and CCE from April 2007 to May 2018. This study included the patients who were treated with neither maintenance dialysis nor steroid before CCE diagnosis, and followed-up for kidney function until November 2019. We assessed whether eosinophilia at the time of CCE diagnosis was related to renal death after treating with steroid therapy.

Results

Thirty patients with pathologically diagnosed CCE were enrolled and followed-up for 11.0 (5.2–43.4) months. There were significant differences in the white blood cell count (p = 0.01), hemoglobin (p = 0.009), serum creatinine levels (p = 0.008), phosphate (p = 0.049), and Eo (p = 0.008) between the renal survival and renal death groups. Using the receiver operating characteristic curve analysis with Youden index, Eo of 810/µL showed 100% sensitivity and 69.6% specificity for detecting renal death (area under the curve: 0.839). Comparing the outcomes in patients having Eo ≥ and < 810/µL using the log-rank test, there is a significantly higher renal death rate in CCE patients with Eo ≥ 810/µL (p = 0.0016).

Conclusion

Higher eosinophilia was a prognostic risk factor for renal death in the patients with CCE.

Atherosclerotic-nephropathy: an updated narrative review

The increased prevalence of chronic kidney disease (CKD) in elderly patients recognizes, as main cause, the long-term exposure to atherosclerosis and hypertension. Chronic ischemic damage due to critical renal arterial stenosis induces oxidative stress and intra-renal inflammation, resulting in fibrosis and microvascular remodelling, that is the histological picture of atherosclerotic renal vascular disease (ARVD). The concomitant presence of a long history of hypertension may generate intimal thickening and luminal narrowing of renal arteries and arterioles, glomerulosclerosis, interstitial fibrosis and tubular atrophy, more typically expression of hypertensive nephropathy. These complex mechanisms contribute to the development of CKD and the progression to End Stage Kidney Disease. In elderly CKD patients, the distinction among these nephropathies may be problematic; therefore, ischemic and hypertensive nephropathies can be joined in a unique clinical syndrome defined as atherosclerotic nephropathy. The availability of novel diagnostic procedures, such as intra-vascular ultrasound and BOLD-MRI, in addition to traditional imaging, have opened new scenarios, because these tools allow to identify ischemic lesions responsive to renal revascularization. Indeed, although trials have deflated the role of renal revascularization on the renal outcomes, it should be still used to avoid dialysis initiation and/or to reduce blood pressure in selected elderly patients at high risk. Nonetheless, lifestyle modifications (smoking cessation, increased physical activity), statins and antiplatelet use, as well as cautious use of renin-angiotensin system inhibitors, remain the main therapeutic approach aimed at slowing the renal damage progression. Mesenchymal stem cells and Micro-RNA are promising target of anti-fibrotic therapy, which might provide potential benefit in ARVD patients, though safety and efficacy profile in humans is unknown too.

[Update on cholesterol crystal embolism]

Cholesterol crystal embolism is a systemic pathology associated with diffuse atherosclerosis. Pathophysiology corresponds to tissue necro-inflammation secondary to arteriolar occlusion associated with microembolism from atherosclerotic plaques of large diameter arteries. The clinical presentation is heterogeneous and polymorphic. Multiple organs may be the targets, but preferential damage is skin, kidneys and digestive system. It is a serious pathology, underdiagnosed, with a poor prognosis. The risk factors for developing the disease remain the same risk factors as atheroma. The factors favouring migration of microembolism remain mainly vascular interventional procedures; easy to diagnose, they oppose spontaneous embolic migrations or secondary to the introduction of antithrombotic treatment, whose diagnosis is more difficult and the prognosis more severe. The diagnosis of the disease remains mostly a diagnosis of elimination and often refers to a bundle of clinical, biological, morphological and histologic arguments. The treatment is poorly codified and the subject of few publications. It will favour both symptomatic treatment (and mainly that of pain) and complications (high blood pressure, renal insufficiency). The aetiological support remains less consensual. The treatment of atherosclerotic plaques consists, of course, in the correction of classical cardiovascular risk factors, the introduction of a statin. It will be discussed in the implementation of surgery or angioplasty to exclude potentially responsible atherosclerotic lesions. Eviction of antithrombotic therapy should be considered in terms of the benefit-risk balance, but often in favour of maintaining it. Finally, other treatments may be proposed in a case-by-case basis, such as oral or intravenous corticosteroid therapy, colchicine or LDL aphaeresis.

Atheroembolic Renal Disease: A Case Series

Atheroembolic renal disease (AERD), a part of systemic cholesterol embolization syndrome, is caused by the occlusion of small arteries in the kidneys by cholesterol crystal emboli from ulcerated atherosclerotic plaques. Kidney is commonly involved because of its proximity to the abdominal aorta and its enormous blood supply. AERD is an under diagnosed condition. We report eight cases of AERD, highlighting the variability in its clinical presentation and the importance of a renal biopsy to arrive at a definitive diagnosis.

[Kidney disease care for the elderly]

In our aging population, kidney disease management needs to take into account the frailty of the elderly. Standardized geriatric assessments can be proposed to help clinicians apprehend this dimension in their daily practice. These tools allow to better identify frail patients and offer them more personalized and harmless treatments. This article aims to focus on the kidney diseases commonly observed in elderly patients and analyze their specific nephrogeriatric care modalities. It should be noticed that all known kidney diseases can be also observed in the elderly, most often with a quite similar clinical presentation. This review is thus focused on the diseases most frequently and most specifically observed in elderly patients (except for monoclonal gammopathy associated nephropathies, out of the scope of this work), as well as the peculiarities of old age nephrological care.

Atheroembolism to the Breast

We report the case of a woman presenting with livedo reticularis of the breast who was found to have atheroembolism to the breast following upper extremity percutaneous access. Atheroembolism is the embolization of cholesterol crystals off an atherosclerotic plaque that can occur spontaneously or as a result of vascular intervention. This is a unique presentation of an otherwise well-described complication of vascular catheterization, and we propose that livedo reticularis of the breast can be interpreted as a sign of atheroembolism in the appropriate clinical context.

Cholesterol-embolization syndrome: current perspectives

Cholesterol-embolization syndrome (CES) is a multisystemic disease with various clinical manifestations. CES is caused by embolization of cholesterol crystals (CCs) from atherosclerotic plaques located in the major arteries, and is induced mostly iatrogenically by interventional and surgical procedures; however, it may also occur spontaneously. Embolized CCs lead to both ischemic and inflammatory damage to the target organ. Therefore, anti-inflammatory agents, such as corticosteroids and cyclophosphamide, have been investigated as treatment for CES in several studies, with conflicting results. Recent research has revealed that CES is actually a kind of autoinflammatory disease in which inflammasome pathways, such as NLRP3 and IL1, are induced by CCs. These recent findings may have clinical implications such that colchicine and IL1 inhibitors, namely canakinumab, may be beneficial in the early stages of CES.

A rare presentation of spontaneous atheroembolic renal disease: A case report

BACKGROUND

Atheroembolic renal disease (AERD) is caused by occlusion of the small renal arteries from embolized cholesterol crystals arising from ulcerated atherosclerotic plaques. This usually manifests as isolated renal disease or involvement from systemic atheroembolic disease. Here we report a case of AERD that responded well to steroid therapy.

CASE SUMMARY

A 62-year-old woman with a history of hypertension and stage IIIa chronic kidney disease was referred for rapidly worsening renal function over a 4-mo period. She complained of swollen legs, dyspnea on exertion, and two episodes of epistaxis about a month prior to admission. She reported no history of invasive vascular procedures, use of radio contrast agents, or treatment with anticoagulants or thrombolytic agents. Urinalysis showed a few red blood cells and granular casts. Serology was positive for cytoplasmic antineutrophil cytoplasmic antibodies (c-ANCA). Non-contrast-enhanced computed tomography of the chest, abdomen, and pelvis showed diffuse atherosclerotic changes in the aortic arch. Thus, c-ANCA-associated vasculitis was suspected, and the patient was started on pulse intravenous methylprednisolone. Her renal biopsy showed evidence of AERD. She was discharged with oral prednisone, and her renal function continued to improve during the initial follow-up.

CONCLUSION

In cases of non-vasculitis-associated ANCA, a high degree of clinical suspicion is required to pursue the diagnosis of spontaneous AERD in patients with clinical or radiological evidence of atherosclerotic burden. Although no specific treatment is available, the potential role of statins and steroids requires exploration.

Long-term outcome of biopsy-proven cholesterol crystal embolism

BACKGROUND

Cholesterol crystal embolism (CCE) causes renal damage, and there is an extremely high risk of end-stage renal disease. However, the time course of CCE-related renal deterioration varies and little is known about the subsequent risk of dialysis among patients with biopsy-proven CCE.

METHODS

We performed a retrospective cohort study of 38 Japanese patients in whom a histological diagnosis of CCE was made from September 1992 to July 2005. Competing risk regression analysis was used to investigate the association between declining renal function ( ≥ 1.5 elevation of serum creatinine within 26 weeks after CCE) or its subtypes (acute [ < 1 week after CCE], subacute [1 to < 6 weeks], and chronic [6 to < 26 weeks]) and the risk of dialysis, with adjustment for age, baseline serum creatinine, and the precipitating event (iatrogenic or spontaneous).

RESULTS

During a median follow-up period of 25.9 weeks, 14 patients (35.9%) started dialysis. Multivariable analysis showed that patients with declining renal function had a higher risk of commencing dialysis than those without declining function (subdistribution hazard ratio [SHR] 9.47; 95% confidence interval [CI] 1.34-66.8). Patients with different renal presentations had a similarly increased risk of commencing dialysis, with the risk being significantly higher for the subacute and chronic patterns of declining renal function (adjusted SHR [95% CI] for acute, subacute, and chronic declining renal function[vs. no decline]: 7.36 [0.85-63.6], 11.9 [1.36-101], and 10.7 [1.49-77.0], respectively).

CONCLUSION

Declining renal function after CCE, even later than 6 weeks, was significantly associated with the subsequent risk of dialysis.

Impact of vascular access on the development of contrast induced nephropathy in patients undergoing coronary angiography and/or percutaneous coronary intervention

BACKGROUND

Contrast induced nephropathy (CIN) is a common complication of procedures that foresee the use of contrast media. Several risk factors have been identified as independent predictors of CIN, but, to date, no definitive data are available about the association between the angiographic approach and its development.

METHODS AND RESULTS

Our population included 4199 patients undergoing coronary angiography and/or PCI. CIN was defined as an absolute ≥0.5 mg/dl or a relative ≥25% increase in creatinine level at 24-48 h after the procedure without another clear cause for the acute kidney injury. The total incidence of CIN was 12.4%. We divided our population into two groups, according to the angiographic approach: transradial (TR) n = 1915 or transfemoral (TF) n = 2284. Patients treated with TR approach were more often males, with history of hypertension, and PCI, but less often diabetic, with previous myocardial infarction, coronary artery by-pass graft surgery and cerebrovascular accident. They had a higher ejection fraction, higher prevalence of PCI, elective indication but interestingly a lower amount of contrast volume. Patients treated with TR approach had higher platelets, Total, LDL and HDL cholesterol, but lower triglycerides, glycaemia and basal creatinine. No significant difference was observed between the two groups regarding the development of CIN (TR 13.2% vs TF 11.7%, p = 0.16). The absence of association between angiographic approach and the incidence of CIN was also confirmed at multivariate analysis after correction for baseline confounders (Adjusted OR [95% CI] = 1.2 [0.97-1.50], p = 0.09) and at subgroup analysis according to main risk factors for CIN. Similar results were obtained dividing our population according to propensity score tertiles: 1st Tertile CIN (TF 8.8% vs TR 8.9%), p = 0.95; OR (99% CI) = 1.01 (0.96-1.48), p = 0.95, 2nd Tertile CIN (TF 10.8% vs TR 12.4%), p = 0.35; OR (99% CI) = 1.17 (0.84-1.62), p = 0.35, and 3rd Tertile CIN (TF 15.6% vs TR 17.2%), p = 0.41; OR (99% CI) = 1.12 (0.85-1.48), p = 0.41.

CONCLUSION

This is the first large study showing the absence of relationship between the angiographic access and the incidence of CIN.

Acute Kidney Injury Post Cardiac Catheterization: Does Vascular Access Route Matter?

BACKGROUND

Acute Kidney Injury as a complication of cardiac catheterization is associated with increased length of hospital stay and mortality. In recent years, the use of the radial artery for cardiac catheterization is increasing in frequency.

OBJECTIVE

The objective of this concise review was to evaluate the method of cardiac access site and its impact on Acute Kidney Injury following cardiac catheterization.

METHODS

After a thorough search on Medline, Google Scholar and PubMed, we included all the literature relevant to Acute kidney injury following transradial and transfemoral cardiac catheterization.

RESULTS

While acute kidney injury was caused due to a variety of reasons, it was important to consider each case on an individual basis. We found a trend towards increased use of transradial approach in patients at high risk of developing kidney injury. However, limitations such as operator experience, anatomical challenges and so on do exist with this approach.

CONCLUSION

Transradial access offers several advantages to a patient at high risk of acute kidney injury undergoing cardiac catheterization. Further large studies are needed to establish this trend in the years ahead.

Eosinophilia and Kidney Disease: More than Just an Incidental Finding?

Peripheral blood eosinophilia (PBE), defined as 500 eosinophils or above per microliter (µL) blood, is a condition that is not uncommon but often neglected in the management of patients with chronic kidney disease (CKD), acute kidney injury (AKI), or patients on renal replacement therapy (RRT). The nature of PBE in the context of kidney diseases is predominantly secondary or reactive and has to be distinguished from primary eosinophilic disorders. Nonetheless, the finding of persistent PBE can be a useful clue for the differential diagnosis of underdiagnosed entities and overlapping syndromes, such as eosinophilic granulomatosis with polyangiitis (EGPA), IgG4-related disease (IgG4-RD), acute interstitial nephritis (AIN), or the hypereosinophilic syndrome (HES). For patients on RRT, PBE may be an indicator for bio-incompatibility of the dialysis material, acute allograft rejection, or Strongyloides hyperinfection. In a subset of patients with EGPA, eosinophils might even be the driving force in disease pathogenesis. This improved understanding is already being used to facilitate novel therapeutic options. Mepolizumab has been licensed for the management of EGPA and is applied with the aim to abrogate the underlying immunologic process by blocking interleukin-5. The current article provides an overview of different renal pathologies that are associated with PBE. Further scientific effort is required to understand the exact role and function of eosinophils in these disorders which may pave the way to improved interdisciplinary management of such patients.

An atypical presentation of a severe and massive atheroembolic disease

Atheroembolic renal disease (AERD) is a kidney manifestation of atherosclerosis as a systemic disease. AERD is defined as a renal impairment secondary to embolization of cholesterol crystals with consequent occlusion of renal vascularization. The current case report describes one patient with multiple risk factors but without any inciting event history who presents a very atypical clinical course of a severe and massive atheroembolic disease that developed spontaneously and silently.

Cholesterol embolization syndrome: An under-recognized entity in cardiovascular interventions

Cholesterol embolization syndrome (CES) is a multi-systemic disease caused by embolization of atherosclerotic plaque contents from proximal large-caliber artery to distal small to medium arteries, occurring spontaneously or more commonly after vascular intervention. This report is a comprehensive review of the reported cases of CES found in our literature search. We discuss the risk factors, clinical manifestations, management, and prognosis of CES. The major predisposing factors for CES include older age, male sex, atherosclerotic cardiovascular risk factors, anticoagulation, and femoral access route. The composite incidence of atheroembolic renal disease was 92% and mortality 63%. Our review highlights the importance to recognize this disease entity for the cardiologist and nephrologist.

Cholesterol Crystal Embolism and Chronic Kidney Disease

Renal disease caused by cholesterol crystal embolism (CCE) occurs when cholesterol crystals become lodged in small renal arteries after small pieces of atheromatous plaques break off from the aorta or renal arteries and shower the downstream vascular bed. CCE is a multisystemic disease but kidneys are particularly vulnerable to atheroembolic disease, which can cause an acute, subacute, or chronic decline in renal function. This life-threatening disease may be underdiagnosed and overlooked as a cause of chronic kidney disease (CKD) among patients with advanced atherosclerosis. CCE can result from vascular surgery, angiography, or administration of anticoagulants. Atheroembolic renal disease has various clinical features that resemble those found in other kidney disorders and systemic diseases. It is commonly misdiagnosed in clinic, but confirmed by characteristic renal biopsy findings. Therapeutic options are limited, and prognosis is considered to be poor. Expanding knowledge of atheroembolic renal disease due to CCE opens perspectives for recognition, diagnosis, and treatment of this cause of progressive renal insufficiency.

Acute Kidney Injury After Radial or Femoral Access for Invasive Acute Coronary Syndrome Management: AKI-MATRIX

BACKGROUND

It remains unclear whether radial access (RA), compared with femoral access (FA), mitigates the risk of acute kidney injury (AKI).

OBJECTIVES

The authors assessed the incidence of AKI in patients with acute coronary syndrome (ACS) enrolled in the MATRIX-Access (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox) trial.

METHODS

Among 8,404 patients, 194 (2.3%) were excluded due to missing creatinine values, no or an incomplete coronary angiogram, or previous dialysis. The primary AKI-MATRIX endpoint was AKI, defined as an absolute (>0.5 mg/dl) or a relative (>25%) increase in serum creatinine (sCr).

RESULTS

AKI occurred in 634 patients (15.4%) with RA and 712 patients (17.4%) with FA (odds ratio [OR]: 0.87; 95% confidence interval [CI]: 0.77 to 0.98; p = 0.0181). A >25% sCr increase was noted in 633 patients (15.4%) with RA and 710 patients (17.3%) with FA (OR: 0.87; 95% CI: 0.77 to 0.98; p = 0.0195), whereas a >0.5 mg/dl absolute sCr increase occurred in 175 patients (4.3%) with RA versus 223 patients (5.4%) with FA (OR: 0.77; 95% CI: 0.63 to 0.95; p = 0.0131). By implementing the Kidney Disease Improving Global Outcomes criteria, AKI was 3-fold less prevalent and trended lower with RA (OR: 0.85; 95% CI: 0.70 to 1.03; p = 0.090), with stage 3 AKI occurring in 28 patients (0.68%) with RA versus 46 patients (1.12%) with FA (p = 0.0367). Post-intervention dialysis was needed in 6 patients (0.15%) with RA and 14 patients (0.34%) with FA (p = 0.0814). Stratified analyses suggested greater benefit with RA than FA in patients at greater risk for AKI.

CONCLUSIONS

In ACS patients who underwent invasive management, RA was associated with a reduced risk of AKI compared with FA. (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX [MATRIX]; NCT01433627).

Performing Anticoagulation: A Puzzling Case of Cholesterol Embolization Syndrome

The avoidance of any form of anticoagulation is advised in cases of cholesterol embolization syndrome (CES). We herein describe a case of CES in a man with a history of unprovoked pulmonary embolism for which warfarinization was performed. Despite anecdotal reports of successful anticoagulation in CES patients with certain indications, irreversible renal failure, which was sufficiently severe to require chronic hemodialysis, eventually developed in our patient. Our results emphasize the pitfalls of this procedure, which imply its limited feasibility and safety. Several therapeutic concerns associated with this case are also discussed.

Cholesterol crystal embolization following plaque rupture: a systemic disease with unusual features

Cholesterol crystal embolic (CCE) syndrome is often a clinically challenging condition that has a poor prognostic implication. It is a result of plaque rupture with release of cholesterol crystals into the circulation that embolize into various tissue organs. Plaque rupture seems to be triggered by an expanding necrotic core during cholesterol crystallization forming sharp tipped crystals that perforate and tear the fibrous cap. Embolizing cholesterol crystals then initiate both local and systemic inflammation that eventually lead to vascular fibrosis and obstruction causing symptoms that can mimic other vasculitic conditions. In fact, animal studies have demonstrated that cholesterol crystals can trigger an inflammatory response via NLRP3 inflammasome similar to that seen with gout. The diagnosis of CCE syndrome often requires a high suspicion of the condition. Serum inflammation biomarkers including elevated sedimentation rate, abnormal renal function tests and eosinophilia are useful but non-specific. Common target organ involvement includes the skin, kidney, and brain. Various testing including fundoscopic eye examination and other non-invasive procedures such as trans-esophageal echocardiography and magnetic resonance imaging may be helpful in identifying the embolic source. Treatment includes aspirin and clopidogrel, high dose statin and possibly steroids. In rare cases, mechanical intervention using covered stents may help isolate the ruptured plaque. Anticoagulation with warfarin is not recommended and might even be harmful. Overall, CCE syndrome is usually a harbinger of extensive and unstable atherosclerotic disease that is often associated with acute cardiovascular events.

Chronic Kidney Disease Progression and Cardiovascular Outcomes Following Cardiac Catheterization-A Population-Controlled Study

BACKGROUND

Studies of kidney disease associated with cardiac catheterization typically rely on billing records rather than laboratory data. We examined the associations between percutaneous coronary interventions, acute kidney injury, and chronic kidney disease progression using comprehensive Veterans Affairs clinical and laboratory databases.

METHODS AND RESULTS

Patients undergoing percutaneous coronary interventions between 2005 and 2010 (N=24 405) were identified in the Veterans Affairs Clinical Assessment, Reporting, and Tracking registry and examined for associated acute kidney injury and chronic kidney disease development or progression relative to 24 405 matched population controls. Secondary outcomes analyzed included dialysis, acute myocardial infarction, and mortality. The incidence of chronic kidney disease progression following percutaneous coronary interventions complicated by acute kidney injury, following uncomplicated coronary interventions, and in matched controls were 28.66, 11.15, and 6.81 per 100 person-years, respectively. Percutaneous coronary intervention also increased the likelihood of chronic kidney disease progression in both the presence and absence of acute injury relative to controls in adjusted analyses (hazard ratio [HR], 5.02 [95% CI, 4.68-5.39]; and HR, 1.76 [95% CI, 1.70-1.86]). Among patients with estimated glomerular filtration rate <60 mL/min per 1.73 m2, acute kidney injury increased the likelihood of disease progression by 8-fold. Similar results were observed for all secondary outcomes.

CONCLUSIONS

Acute kidney injury following percutaneous coronary intervention was associated with increased chronic kidney disease development and progression and mortality.

Anti-neutrophil cytoplasmic antibodies in cholesterol embolism: A case report and literature review

Cholesterol embolism is a multisystemic disorder with clinical manifestations that resemble vasculitis. Anti-neutrophil cytoplasmic antibodies (ANCA) are a defining feature of ANCA-associated vasculitis, and the presence of ANCA in cholesterol embolism complicates its differential diagnosis and treatment. At present, the role of ANCA in cholesterol embolism remains unclear and no effective treatment is currently available. The present study reports the case of an Asian male who presented with spontaneous cholesterol embolism with proteinase 3 (PR3)-specific ANCA, subacute interstitial nephritis and late-developing skin lesions. The 69-year-old patient was admitted to The First Affiliated Hospital of Xiamen University (Xiamen, China) complaining of chest tightness, fatigue, progressive renal failure and refractory hypertension. In addition, transient eosinophilia was detected. Following immunosuppressive therapy with steroids and cyclophosphamide for 6 months, hemodialysis treatment was initiated. Skin lesions appeared at >1 month following hemodialysis initiation; however, they were gradually improved following treatment with atorvastatin and anti-platelet aggregation therapy for 5 months. The patient was maintained on hemodialysis for ~2 years and exhibited general good health at the most recent follow-up. In addition, 11 cases of cholesterol embolism associated with ANCA reported in the literature were discussed in the present study.