The role of aortic stent grafting in the treatment of atheromatous embolization syndrome: Results after a mean of 15 months follow-up

Real-World Outcomes of Carotid Artery Stenting in Symptomatic and Asymptomatic Patients With Carotid Artery Stenosis

BACKGROUND

The effectiveness and safety of carotid artery stenting (CAS) are comparable to those of carotid endarterectomy in both symptomatic and asymptomatic patients with carotid artery stenosis, but real-world outcomes are not well-known.

OBJECTIVES

The purpose of this study was to investigate the real-world clinical outcomes of CAS in symptomatic and asymptomatic patients with carotid artery stenosis.

METHODS

We conducted a nationwide retrospective registry study of 156 centers between January 2015 and December 2019. We enrolled consecutive patients with CAS managed by certified specialists from the Japanese Society of Neuroendovascular Therapy. Outcomes between symptomatic and asymptomatic patients were compared. The primary outcome was a composite of ischemic stroke and all-cause death at 30 days after CAS. Secondary outcomes were ischemic stroke, all-cause death, intracranial hemorrhage (ICH), and procedural complications.

RESULTS

We analyzed 9,792 patients (symptomatic, n = 5,351; asymptomatic, n = 4,441). The mean age was 73.5 years, and men were dominant (86.4%). Embolism protection devices were used in 99% of patients. The primary outcome was not significantly different between the symptomatic and asymptomatic groups (120 [2.2%] vs 65 [1.5%]; adjusted OR: 1.30; 95% CI: 0.92-1.83). The incidences of symptomatic ICH, any ICH, acute in-stent occlusion, and hyperperfusion syndrome were significantly more prevalent in the symptomatic group (47 [0.9%] vs 8 [0.2%], aOR: 4.41 [95% CI: 1.68-11.6]; 73 [1.4%] vs 12 [0.3%], aOR: 3.56 [95% CI: 1.71-7.39]; 45 [0.8%] vs 19 [0.4%], aOR: 2.18 [95% CI: 1.08-4.40]; and 102 [1.9%] vs 36 [0.8%], aOR: 1.78 [95% CI: 1.17-2.71], respectively). Other secondary outcomes were not significantly different between the 2 groups.

CONCLUSIONS

The complication rate after specialist-involved CAS at 30 days was low in real-world practice.

Fatal Course of Cutaneous Cholesterol Embolization Syndrome: A Case Report

Cholesterol embolization syndrome is an increasing but underestimated problem after endovascular intervention or after the start of thrombolytic therapies. Embolies from the aortic wall involves abdominal organs and the skin of the lower extremities or buttocks. In our case a progressive ulceration and necroses occurs spontaneously. Endovascular treatment of the lower extremities was successful for a short period. Due to the progression of necrosis, both legs were amputated. Biopsies were taken from the skin were initially no directions to the diagnosis of Cholesterol embolization syndrome. After a second elliptical excision biopsy the diagnosis of cholesterol embolization syndrome was confirmed. Because the rapid progression of skin necroses despite the treatment of prednisone, patient died due to sepsis and renal failure. This case shows when arterial revascularization is performed and progression in skin necrosis occurs despite optimal arterial vascular status the diagnosis CES should be considered and treated in an early state of disease.

Pathophysiology and targeted treatment of cholesterol crystal embolism and the related thrombotic angiopathy

Cholesterol crystal (CC) embolism is a complication of advanced atherosclerotic plaques located in the major arteries. This pathological condition is primarily induced by interventional and surgical procedures or occurs spontaneously. CC can induce a wide range of tissue injuries including CC embolism syndrome, a spontaneous or intervention-induced complication of advanced atherosclerosis, while treatment of CC embolism has remained empiric. Vascular occlusions caused by CC embolism may exceed the ischemia tolerance of many tissues, particularly when small arteries are affected. The main approach to CC embolism is primary prophylaxis in patients at risk by stabilizing atherosclerotic plaques and avoiding unnecessary catheter interventions. During CC embolism, the use of platelet inhibitors to avoid abnormal activation and aggregation and anticoagulants may reduce the risk of vascular occlusions and tissue ischemia. This probably explains the relatively low prevalence of clinical manifestations of CC embolism, which are frequently found in autopsy studies. In this review, we summarized the current knowledge on the pathophysiology of CC embolism syndrome deriving from clinical observations and experimental mouse models. Furthermore, we described the risk factors of CC embolism in humans as well as the experimental studies based on empiric treatments. We also discuss potential therapeutic interventions based on recent experimental data and emerging drug options evolving from other research domains. Given the substantial unmet medical need to improve the outcomes of CC embolism, the identification of effective treatment strategies is urgently needed.

Acute type B aortic dissection with multiple cholesterol embolism: an autopsy case report

Background

Most cases of cholesterol embolism are known to be triggered by cardiac catheterization, cardiovascular surgery, anticoagulation, or fibrinolytic therapy; however, spontaneous cases after aortic dissection are rare. In this report, we describe a case of cholesterol embolism after type B aortic dissection, which rapidly developed into multiple organ failure and death.

Case summary

A 65-year-old man with untreated hypertension was admitted to our hospital with sudden back pain and diagnosed with type B aortic dissection. The patient experienced a rapid progression of inflammation and developed respiratory and renal failure, despite computed tomography showing no obvious progression of dissection. We attributed them to a cytokine storm and acute respiratory distress syndrome, but steroid pulse therapy did not alleviate the symptoms. Finally, the patient died on Day 6 after admission, and an autopsy was performed, which revealed cholesterol crystal occlusions in the kidney, spleen, and the left lower leg. The lumen in the aorta is filled with atheroma and thrombus, and we suspect that aortic dissection triggered failure of the aortic plaques and released cholesterol crystals to distal arteries that led to cholesterol embolism.

Discussion

We experienced a patient with a type B aortic dissection that led to cholesterol embolism and rapid progression of respiratory and renal failure, resulting in death. The aortic dissection combined with cholesterol embolism was considered to trigger the subsequent severe inflammation, leading to rapid respiratory and renal failure. Our case points to the possibility that cholesterol embolism can extensively escalate inflammation after aortic dissection.

Single-Center Experience with Simultaneous Mural Aortic Thrombosis and Peripheral Obstructive Disease in Pre-COVID-19 and COVID-19 Era

BACKGROUND

Mural aortic thrombosis associated with chronic peripheral obstruction of the lower limbs is an unusual event. Repeated embolism of instability aortic mural thrombosis caused acute limb ischemia (Rutherford 2 classification) in patients with peripheral arterial disease (PAD). We report a single-center experience for patients with transmural aortic thrombosis and peripheral artery disease.

METHODS

We retrospectively analyzed data of 54 patients with aortic mural thrombus disease with PAD presentation, treated at our center between 2013 and 2022.

RESULTS

Thirty patients (six with proven SARS-CoV-2 infection) underwent hybrid or staged treatment for an aortic lesion and for lower limb ischemia, by the placement of an endovascular aortic stent graft and a femoro-distal or a popliteal-distal bypass graft. The remaining 24 cases were only subjected to an intravascular treatment of the thoracic or abdominal aorta. Transient renal failure occurred in three patients. No embolic events were detected during the procedures. Aortic-related mortality was reported in just one patient who died from multiple organ failure. There was an embolic stroke in one patient with proven SARS-CoV-2 infection, three major amputations in patients with proven SARS-CoV-2 infection and no aortic-related mortality.

CONCLUSIONS

Stent coverage of complex aortic lesions, alone or in association with a distal bypass graft, supports this approach in a variety of settings. The COVID-19 pandemic caused an increased mortality and amputation rate.

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.

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.

[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.

Endovascular Repair of Thoracic Aortic Disease: Early and Midterm Experience

Thoracic aorta disease remains a challenging problem, and despite improvements, open repair techniques are still associated with significant morbidity and mortality. This is a retrospective review of 53 consecutive patients with thoracic aortic pathology who were treated with endovascular repair between September 1998 and December 2004 at a tertiary-care hospital. Endovascular stent graft placement was performed on 23 elective and 30 emergent patients (34 male patients, mean age 66 years, 21 to 85 years). Completion angiography revealed no endoleak in 47 (89%) patients, a type I endoleak in 4 patients, and a type II endoleak in 2 patients. Operative 30-day mortality for elective aneurysms (n = 22), emergent aneurysms (n = 10), dissection (n = 3), penetrating aortic ulcers (n = 7), and trauma (n = 11) was 0%, 40%, 0%, 29%, and 9%, respectively. In total, 46 (87%) patients survived 30 days, and 36 (78.3%) of the survivors were discharged home free of complications. Two patients (4%) experienced paraplegia. Median follow-up was 22 months (1 to 72 months). Intermediate-term results revealed 41 (89%) patients free of endoleak, stent migration, or aneurysmal expansion. Two (4%) patients required reintervention with an additional stent graft. There were 2 (4%) patients with late aortic-related deaths and four (9%) patients with non—aorticrelated late deaths. Endovascular stent graft placement for thoracic aorta disease can be performed successfully and safely with good perioperative and intermediate-term outcomes. Stent graft complication and reintervention rates are low, whereas intermediate survival rates are good. Long-term efficacy still needs to be evaluated.

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.

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 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.

Atheromatous embolization

Atheromatous embolization is a multisystem disease complicating advanced atherosclerosis. It occurs most often as a complication of angiography, an endovascular procedure or cardiovascular surgery. Atheromatous embolization can present in a subtle manner where it is often under-recognized, or with catastrophic results including myocardial infarction, strake or acute renal failure. It may mimic other disease processes and often goes underdiagnosed and undertreated. A high clinical suspicion is the key to diagnosis. Atheromatous embolization results in significant morbidity and mortality; therefore, early recognition followed by aggressive management may help to prevent end-organ damage and improve overall clinical outcomes. Management strategies should include risk factor modification, prevention of further insults by discontinuing or avoiding predisposing factors, supportive treatment and interventional or surgical approaches to remove the atheroembolic source. Atheromatous embolization is expected to increase as our population ages and the epidemics of diabetes mellitus and obesity increase.

Endovascular strategies for treatment of embolizing thoracoabdominal aortic lesions

OBJECTIVE

Aortic sources of peripheral and visceral embolization remain challenging to treat. The safety of stent graft coverage continues to be debated. This study reports the outcomes of stent coverage of these complex lesions.

METHODS

Hospital records were retrospectively reviewed for patients undergoing aortic stenting between 2006 and 2013 for visceral and peripheral embolic disease. Renal function, method of coverage, and mortality after stent grafting were reviewed.

RESULTS

Twenty-five cases of embolizing aortic lesions treated with an endovascular approach were identified. The mean age was 65 ± 13 years (range, 45-87 years), and 64% were female. Sixteen (64%) patients presented with peripheral embolic events, six with concomitant renal embolization. Five patients presented with abdominal or flank pain, and two were discovered incidentally. Three patients had undergone an endovascular procedure for other indications within the preceding 6 months of presentation. Nineteen patients had existing chronic kidney disease (stage II or higher), but only three had stage IV disease. Of the eight patients tested, four had a diagnosed hypercoagulable state. Eight of the patients had lesions identified in multiple aortic segments, and aortic aneurysm disease was present in 24%. Coverage of both abdominal and thoracic sources occurred in eight patients, whereas 17 had only one segment covered. Minimal intraluminal catheter and wire manipulation was paired with the use of intravascular ultrasound in an effort to reduce embolization and contrast use. Intravascular ultrasound was used in the majority of cases and transesophageal echo in 28% of patients. Two patients with stage IV kidney disease became dialysis-dependent within 3 months of the procedure. No other patients had an increase in their postoperative or predischarge serum creatinine levels. No embolic events were precipitated during the procedure, nor were there any recurrent embolic events detected on follow-up. The 1-year mortality rate was 25%.

CONCLUSIONS

Endovascular coverage of atheroembolic sources in the aorta is feasible and is safe and effective in properly selected patients. It does not appear to worsen renal function when performed with the use of specific technical strategies.

Atheroembolic renal disease

Atheroembolic renal disease develops when atheromatous aortic plaques rupture, releasing cholesterol crystals into the small renal arteries. Embolisation often affects other organs, such as the skin, gastrointestinal system, and brain. Although the disease can develop spontaneously, it usually develops after vascular surgery, catheterisation, or anticoagulation. The systemic nature of atheroembolism makes diagnosis difficult. The classic triad of a precipitating event, acute or subacute renal failure, and skin lesions, are strongly suggestive of the disorder. Eosinophilia further supports the diagnosis, usually confirmed by biopsy of an affected organ or by the fundoscopic finding of cholesterol crystals in the retinal circulation. Renal and patient prognosis are poor. Treatment is mostly preventive, based on avoidance of further precipitating factors, and symptomatic, aimed to the optimum treatment of hypertension and cardiac and renal failure. Statins, which stabilise atherosclerotic plaques, should be offered to all patients. Steroids might have a role in acute or subacute progressive forms with systemic inflammation.