Posttraumatic Basal Ganglia Infarction by Lenticulostriate Artery Injury in Adult Patients: A Review

Post-traumatic striatocapsular infarction (SCI) due to lenticulostriate artery (LSA) damage is rare. Most cases reported are in children. We discuss the pathogenesis and differential diagnosis of this kind of SCI after trauma in adult patients. The most common etiology of non-traumatic SCI are an embolism from the proximal artery, cardiogenic embolism, and atherosclerotic plaque in the proximal middle cerebral artery (MCA). However, injury of the LSA after trauma may lead to hemorrhagic infarction in the basal ganglia (BG). Post-traumatic SCI due to LSA damage might be associated with hemorrhage in the BG. The main locations of these lesions are the distal perfusion area of the LSA, similar to SCI due to intracranial atherosclerotic disease affecting the MCA. Vessel wall imaging, magnetic resonance angiography, and ultrahigh-resolution computed tomography can be used for differentiating the injury mechanism in SCI following a traumatic event.

Swine Model of Myocardial Infarction Induced by Ischemia-Reperfusion and Embolization

Acute myocardial infarction continues to account for a growing burden of heart failure worldwide. Despite existing therapies, new approaches for reducing the extent of damage and better managing heart failure progression are urgently needed. Preclinical large animal models are a critical step in the translation of scientific discoveries toward clinical trials and therapeutic application. In this chapter, we detail methods to induce swine models of myocardial infarction through catheter-mediated approaches involving either temporary (ischemia-reperfusion) or permanent (thrombus injection or embolic coil) occlusions. These techniques are relatively low in invasiveness, while infarct size with corresponding cardiac dysfunction can be controlled by adjusting the location of coronary occlusion. We also describe methods for cardiac angiography and echocardiography in pigs. This is the second edition of a previously published chapter with modifications.

Acceleration of the Development of Microcirculation Embolism in the Brain due to Capillary Narrowing

BACKGROUND

Cerebral microvascular obstruction is critically involved in recurrent stroke and decreased cerebral blood flow with age. The obstruction must occur in the capillary with a greater resistance to perfusion pressure through the microvascular networks. However, little is known about the relationship between capillary size and embolism formation. This study aimed to determine whether the capillary lumen space contributes to the development of microcirculation embolism.

METHODS

To spatiotemporally manipulate capillary diameters in vivo, transgenic mice expressing the light-gated cation channel protein ChR2 (channelrhodopsin-2) in mural cells were used. The spatiotemporal changes in the regional cerebral blood flow in response to the photoactivation of ChR2 mural cells were first characterized using laser speckle flowgraphy. Capillary responses to optimized photostimulation were then examined in vivo using 2-photon microscopy. Finally, microcirculation embolism due to intravenously injected fluorescent microbeads was compared under conditions with or without photoactivation of ChR2 mural cells.

RESULTS

Following transcranial photostimulation, the stimulation intensity-dependent decrease in cerebral blood flow centered at the irradiation was observed (14%-49% decreases relative to the baseline). The cerebrovascular response to photostimulation showed significant constriction of the cerebral arteries and capillaries but not of the veins. As a result of vasoconstriction, a temporal stall of red blood cell flow occurred in the capillaries of the venous sides. The 2-photon excitation of a single ChR2 pericyte demonstrated the partial shrinkage of capillaries (7% relative to the baseline) around the stimulated cell. With the intravenous injection of microbeads, the occurrence of microcirculation embolism was significantly enhanced (11% increases compared to the control) with photostimulation.

CONCLUSIONS

Capillary narrowing increases the risk of developing microcirculation embolism in the venous sides of the cerebral capillaries.

Renal angiomyolipoma with inferior vena cava and right atrial embolism: A case report and literature review

Renal angiomyolipoma (AML) with renal vein, inferior vena cava (IVC), and right atrial embolism is a rare solid tumor, whose etiology and pathogenesis are still unclear. Moreover, it is often misdiagnosed. One patient with renal AML complicated with renal vein, IVC, and right atrial embolism was admitted to the Second Xiangya Hospital of Central South University, who was a 35-year-old female, without any previous medical history, presented with right low back pain for more than 3 years. Computed tomography (CT) scan showed irregular lobulated fatty density mass in the right kidney, renal vein, IVC, and right atrium. The contrast-enhanced scan showed no enhancement of fat components at each phase and mild enhancement of solid components. Radical resection of the right kidney and removal of tumor thrombus were performed, and there was no recurrence 1 year after the operation. It is rare for renal AML to grow along the renal vein, IVC, and extend to the right atrium. Imaging examination is extremely important, and the CT findings of this case are characteristic, but the diagnosis eventually depends on pathological and immunohistochemical examinations.

Animal model of coronary microembolization under transthoracic echocardiographic guidance in rats

The aim of the study was to develop a model of coronary microembolization (CME) in rats at a lower cost. We developed a novel rat model without thoracotomy and ventilation under the guidance of echocardiography. Rats were sacrificed at 3 h, 24 h and 1 month postoperatively in both the Echo-CME and Open-chest CME groups for the comparison of the modeling accuracy, mortality, cardiopulmonary circulation, pleural adhesion and ventilation-induced lung injury (VILI). Results showed that the coronary microthrombus formed at 3 h and reached its peak at 24 h postoperatively, which included platelet aggregation and fibrin web. The Echo-group increases success rates, decreased mortality, postoperative complications including pleural adhesion, cardiopulmonary dysfunction and VILI postoperatively than the Open-chest group at 1month postoperatively. The ejection fraction of the CME group decreased to 50% and obvious cardiac fibrosis formed at 3 months postoperatively. Our unique surgical method provided a platform to study molecular mechanisms and potential new pathways for CME treatment.

Cutaneous Polymer-Coating Embolism After Endovascular Procedures: Report of Two Cases and a Literature Review

ABSTRACT

Different hydrophilic and hydrophobic polymers are used as lubricious coatings to reduce vascular traumas in minimally invasive percutaneous procedures. Although they are usually very safe, there is still a risk of serious complications in patients undergoing such procedures, mostly derived from the devices' coating detachment and systemic embolization. The lungs are the most common organ involved, followed by the central nervous system. Yet, cutaneous embolization is unusual, and only 19 cases are available in the literature. Most commonly, they present as asymptomatic retiform purpura on the lower legs, which tends to involve spontaneously. Correct clinical diagnosis is not suspected in most cases, being cholesterol emboly or vasculitis the preferred options. Time interval since surgical procedure and appearance of lesions vary widely but they generally start in the first few days. Histopathological identification of the embolus as bluish, amorphous intraluminal material in dermal vessels is diagnostic, but vasculitic signs are not present. We report 2 cases of skin lesions as the main manifestation of polymer embolization after endovascular surgical procedures. In both cases, biopsy allowed identification of embolized foreign material and lesions resolved without specific treatment.

Liquid silicone embolism syndrome (SES) in lungs and liver - A case report

Silicone embolism syndrome (SES) is a well known complication after injection of silicone gel as well as liquid silicone. Rarely, men use physiologic salt solution or liquid silicone injected into the subcutaneous tissue of the scrotum, the penis, the upper genital or the inguinal region. Those men, who call themselves "siliconers", want to get a larger penis and scrotum, also visible when wearing clothes. Injections of liquid silicone in the mentioned regions can lead to liquid silicone embolism in the lungs and also the liver, sometimes eventually leading to death via right heart failure as in the present case. Autopsy revealed "frog spawn"-like vacuoles in the subcutaneous tissue of the genital region and liquid silicone embolism in lungs and liver. Additionally, toxicological analyses revealed different liquid silicones. Smaller oligomers were transported into lung and liver, larger ones showed local enrichment at the injection site. The seized Polydimethylsiloxane (PDMS) could not be detected in abdominal fat, blood or urine, potentially due to low perfusion of fat tissue, the aqueous character of blood and urine or the time span between last injection and death.

Nicorandil inhibits cardiomyocyte apoptosis and improves cardiac function by suppressing the HtrA2/XIAP/PARP signaling after coronary microembolization in rats

Cardiomyocyte apoptosis is a key factor in the deterioration of cardiac function after coronary microembolization (CME). Nicorandil (NIC) affects myocardial injury, which may be related to the inhibition of apoptosis. However, the specific mechanism of cardioprotection has not been elucidated. Therefore, we analyzed the impact of NIC on cardiac function in rats subjected to CME and its effect on the high-temperature requirement peptidase 2/X-linked inhibitor of apoptosis protein/poly ADP-ribose polymerase (HtrA2/XIAP/PARP) pathway. Sprague Dawley rats were divided into four groups: Sham, CME, CME + NIC, and CME + UCF. Echocardiography was performed 9 hours after CME. Myocardial injury markers were evaluated in blood samples, and the heart tissue was collected for hematoxylin-eosin staining, hematoxylin basic fuchsin picric acid staining staining, TdT-mediated DUTP nick end labeling (TUNEL) staining, Western blot analysis of the HtrA2/XIAP/PARP pathway, and transmission electron microscopy. NIC ameliorated cardiac dysfunctioncaused by CME and reduced serum levels of CK-MB and LDH. In addition, NIC decreased myocardial microinfarct size and apoptotic index. NIC reduced the Bax/Bcl-2 ratio, levels of cleaved caspase 3/9, cytoplasmic HtrA2, and cleaved PARP, and increased the level of XIAP. The effects of NIC were similar to those of the HtrA2 inhibitor, UCF101. This study demonstrated that NIC reduces CME-induced myocardial injury, reduces mitochondrial damage, and improves myocardial function. The reduction in cardiomyocyte apoptosis by NIC may be mediated by the HtrA2/XIAP/PARP signaling pathway.

The risk of stroke/systemic embolism and major bleeding in Asian patients with non-valvular atrial fibrillation treated with non-vitamin K oral anticoagulants compared to warfarin: Results from a real-world data analysis

BACKGROUND

Although randomized trials provide a high level of evidence regarding the efficacy of non-vitamin K oral anticoagulants (NOACs), the results of such trials may differ from those observed in day-to-day clinical practice.

AIMS

To compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) between NOAC and warfarin in clinical practice.

METHODS

Patients with non-valvular atrial fibrillation (NVAF) who started warfarin/NOACs between January 2015 and November 2016 were retrospectively identified from Korea's nationwide health insurance claims database. Using inpatient diagnosis and imaging records, the Cox models with inverse probability of treatment weighting using propensity scores were used to estimate hazard ratios (HRs) for NOACs relative to warfarin.

RESULTS

Of the 48,389 patients, 10,548, 11,414, 17,779 and 8,648 were administered apixaban, dabigatran, rivaroxaban and warfarin, respectively. Many patients had suffered prior strokes (36.7%, 37.7%, 31.4%, and 32.2% in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively), exhibited high CHA2DS2-VASc (4.8, 4.6, 4.6, and 4.1 in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively) and HAS-BLED (3.7, 3.6, 3.6, and 3.3 in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively) scores, had received antiplatelet therapy (75.4%, 75.7%, 76.8%, and 70.1% in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively), or were administered reduced doses of NOACs (49.8%, 52.9%, and 42.8% in apixaban, dabigatran, and rivaroxaban group, respectively). Apixaban, dabigatran and rivaroxaban showed a significantly lower S/SE risk [HR, 95% confidence intervals (CI): 0.62, 0.54-0.71; 0.60, 0.53-0.69; and 0.71, 0.56-0.88, respectively] than warfarin. Apixaban and dabigatran (HR, 95% CI: 0.58, 0.51-0.66 and 0.75, 0.60-0.95, respectively), but not rivaroxaban (HR, 95% CI: 0.84, 0.69-1.04), showed a significantly lower MB risk than warfarin.

CONCLUSIONS

Among Asian patients who were associated with higher bleeding risk, low adherence, and receiving reduced NOAC dose than that provided in randomised controlled trials, all NOACs were associated with a significantly lower S/SE risk and apixaban and dabigatran with a significantly lower MB risk than warfarin.

The Shaggy Aorta Syndrome: An Updated Review

BACKGROUND

Shaggy aorta (SA) depicts the severe aortic surface degeneration, extremely friable, and likely to cause spontaneous peripheral and visceral embolization or during catheterization, aortic manipulation, surgery, or minimally invasive procedures. This study aims to provide the most accurate and up-to-date information on this disease.

METHODS

Potentially eligible studies to be included were identified by searching the following databases: CENTRAL Library, ClinicalTrials.gov, MEDLINE, and CINAHL, using a combination of subject headings and text words to identify relevant studies: (Shaggy aorta) OR (aortic embolization) OR (aortic embolism) OR (aortic thrombus) OR (aortic plaque). From a total of 29,111 abstracts, and after applying inclusion and exclusion criteria, we considered 60 studies for inclusion in this review.

RESULTS

Appropriate measurement and assessment of the aortic wall are pivotal in the modern era, in particular when percutaneous procedures are performed, as SA has been identified as an independent risk factor for spinal cord injury, mesenteric embolization, and cerebral infarction after endovascular aortic repair. Furthermore, SA increases the rate of cerebral complications during transcatheter aortic valve implantation.

CONCLUSIONS

In conclusion, prompt diagnosis of SA syndrome and appropriate guidelines on the management of these conditions may help physicians to better assess the patient risk and to minimize the dreadful-related complications.

The Potential Clinical Implications of Circulating Tumor Cells and Circulating Tumor Microemboli in Gastric Cancer

BACKGROUND

Gastric adenocarcinoma (GAC) is the third deadliest malignant neoplasm worldwide, mostly because of late disease diagnosis, low chemotherapy response rates, and an overall lack of tumor biology understanding. Therefore, tools for prognosis and prediction of treatment response are needed. Quantification of circulating tumor cells (CTCs) and circulating tumor microemboli (CTM) and their expression of biomarkers has potential clinical relevance. Our aim was to evaluate CTCs and CTM and their expression of HER2 and plakoglobin in patients with nonmetastatic GAC, correlating the findings to clinicopathological data.

MATERIALS AND METHODS

CTC enrichment was performed with isolation by size of epithelial tumor cells, and the analysis was performed with immunocytochemistry and microscopy. Two collections were made: one at diagnosis (55 samples before neoadjuvant treatment) and one after surgery and before adjuvant therapy (33 samples).

RESULTS

A high detection rate of CTCs (90%) was observed at baseline. We evaluated HER2 expression in 45/55 biopsy samples and in 42/55 CTC samples, with an overlap of 36 subjects. Besides the good agreement observed for HER2 expression in primary tumors and paired CTCs for 36 cases (69.4%; κ = 0.272), the analysis of HER2 in CTCs showed higher positivity (43%) compared with primary tumors (11%); 3/5 patients with disease progression had HER2-negative primary tumors but HER2-positive CTCs. A significant CTC count drop in follow-up was seen for CTC-HER2-positive cases (4.45 to 1.0 CTCs per mL) compared with CTC-HER2-negative cases (2.6 to 1.0 CTCs per mL). The same was observed for CTC-plakoglobin-positive cases (2.9 to 1.25 CTCs per mL).

CONCLUSION

CTC analysis, including their levels, plakoglobin, and HER2 expression, appears to be a promising tool in the understanding the biology and prognosis of GAC.

IMPLICATIONS FOR PRACTICE

The analysis of circulating tumor cell levels from the blood of patients with gastric adenocarcinoma, before and after neoadjuvant treatment, is useful to better understand the behavior of the disease as well as the patients more likely to respond to treatment.

Acute Ischemic Stroke due to Undifferentiated Sarcoma: A Case Report and Literature Review

Tumor emboli due to a sarcoma are usually confirmed by an autopsy or operative findings. A sarcoma embolus in an acute stroke patient is rare. We herein report a 37-year-old man with acute stroke caused by internal carotid artery occlusion who underwent embolectomy. A histopathological analysis of an embolus obtained with a mechanical retriever device was diagnosed as undifferentiated sarcoma. This is the first case of extracardiac sarcoma extraction via mechanical retrieval performed during intervention for acute ischemic stroke. A histopathologic evaluation with embolectomy is important for diagnosing tumor emboli.

Synchronous double superficial mixed gastrointestinal mucus phenotype gastric cancer with gastritis cystica profunda and submucosal lipoma: A case report

INTRODUCTION

Synchronous double superficial gastric cancer with gastritis cystica profunda (GCP) and submucosal lipoma is a rare disease and is difficult to diagnose and treat.

CASE PRESENTATION

A 61-year-old man was referred to our hospital with upper abdominal discomfort for the past 10 days. One year ago, the patient underwent surgery for duodenal ulcer and perforation. The diseases were diagnosed by magnifying endoscopy with narrowband imaging and pathological methods. Both mucosal lesions with a submucosal yellow-colored nodule were completely resected by endoscopic submucosal dissection and additional proximal gastrectomy was performed on the cancer embolus in the submucosal vena cava. The patient was finally diagnosed with synchronous double superficial well differentiated adenocarcinoma (mixed gastrointestinal mucus phenotype) with embolus in submucosal vena cava, coexisting with gastritis cystica profunda and submucosal lipoma. Final TNM classification was T1b (sm1) N0M0, and pathological stage was IA. The postoperative course was uneventful, and no recurrence or metastasis was observed during the 5-month follow-up period.

CONCLUSION

The diagnosis and treatment of synchronous double superficial gastric cancer with GCP and submucosal lipoma is challenging. In addition, elastic fiber staining and immune marker staining is effective and should be considered for diagnosis.

Potential Involvement of MiR-30e-3p in Myocardial Injury Induced by Coronary Microembolization via Autophagy Activation

BACKGROUND/AIMS

Coronary microembolization (CME) can lead to no-reflow or slow reflow, which is one of the important reasons for loss of clinical benefit from myocardial reperfusion therapy. MicroRNAs and autophagy are heavily implicated in the occurrence and development of almost all cardiovascular diseases. Therefore, the present study was designed to investigate the role of miR-30e-3p and autophagy in CME-induced myocardial injury rat model.

METHODS

Sixty rats were randomly divided into six groups: sham, CME 1h,3h,6h,9h, and 12h (n = 10 per group). Our CME rat model was created by injecting polyethylene microspheres (42mm) into the left ventricle of the heart; the sham group was injected with same volume of normal saline. The cardiac function and serum cardiac troponin I (cTnI) level of each group was measured. HE staining and HBFP staining were used to evaluate the myocardial micro-infarction area of myocardium tissue samples. Then RT-qPCR and western blot were used to detect the expression of miR-30e-3p and, autophagy related protein LC3-II and p62, respectively. Transmission electron microscope (TEM) was used to identify autophagic vacuoles in tissue samples.

RESULTS

The cardiac function of the CME 6h,9h, and 12h groups were significantly decreased compared to the sham group (P < 0.05) and the cTnI level in each group were also significantly increased (P < 0.05). The expression of miR-30e-3p in the CME 6h, 9h and 12h group were decreased significantly compared with the sham group (P < 0.05). Meanwhile, the expression of autophagy related protein LC3-II decreased significantly and p62 increased significantly in the CME 9h and 12h group (P < 0.05). TEM images showed typical autophagic vacuoles for each of the CME groups.

CONCLUSIONS

Myocardial miR-30e-3p is down regulated after CME and is accompanied by inhibited autophagy and decreased cardiac function. Therefore, miR-30e-3p may be involved in CME-induced cardiac dysfunction by regulating myocardial autophagy.

Different infarction patterns in patients with aortic atheroma compared to those with cardioembolism or large artery atherosclerosis

Aortic atheroma is a known cause of ischemic stroke. However, it is unclear whether ischemic stroke is caused by emboli from aortic atheroma or by accompanying atherosclerosis. In this study, we evaluated lesion patterns of patients with complex aortic plaque (CAP) to assume the underlying pathophysiology. Acute ischemic stroke patients who underwent transesophageal echocardiography were included. CAP was defined as a plaque in the proximal aorta ≥ 4 mm thick or with a mobile component. The diffusion-weighted imaging lesion patterns of patients with CAP were compared to those with large arterial atherosclerosis (LAA) or cardioembolism (CE). A total of 64 CAP patients, 127 LAA patients, and 80 CE patients were included. Small cortical pattern was more common in the CAP group (45.3%) than in the LAA (7.9%, p < 0.001) or the CE group (23.8%, p = 0.018). A large cortical pattern was more common in the CE group than in the CAP group (p < 0.001), whereas subcortical only pattern tended to be more common in the CAP group than in the CE group (p = 0.057). In multinominal analysis, the CAP group was more likely to have a small cortical lesion than the LAA group [odds ratio (OR) 14.63; 95% confidence interval (CI) 4.67-45.85] or the CE (OR 3.69, 95% CI 1.19-11.39) group. In conclusion, patients with CAP frequently had small cortical lesions or subcortical single lesion. These findings imply that ischemic stroke in aortic atheroma patients is associated with either small emboli or small artery disease.

Swirling of microbubbles: Demonstration of a new finding of carotid plaque ulceration on contrast-enhanced ultrasound explaining the arterio-arterial embolism mechanism

Carotid plaque ulceration is a well-established feature of vulnerability, associated with high risk for neurological symptoms. From a pathogenetic point of view, the mechanism responsible for occurrence of symptomatology relies on the aggregation of platelets within the ulcer cavity, activation of coagulation mechanism, formation of thrombus and arterio-arterial embolization of thrombotic material in the central nervous system. Many imaging modalities including unenhanced ultrasound, computed tomographic angiography and magnetic resonance angiography have been used to image and diagnose carotid plaque ulceration with varying success. Contrast-enhanced ultrasound has been recently introduced in the study of carotid disease offering improved flow visualization and better plaque surface delineation. We present a case where contrast-enhanced ultrasound visualized the swirling pattern of movement of the microbubbles within the ulcer cavity. These findings illustrate the underlying hemodynamic mechanism of arterio-arterial embolization and can be proposed as a new finding of plaque ulcerations on contrast-enhanced ultrasound.

Limb ischemia, an alarm signal to a thromboembolic cascade - renal infarction and nephrectomy followed by surgical suppression of the left atrial appendage

We present the case of a 55-year-old male with mild hypertension and brief episodes of paroxysmal self-limiting atrial fibrillation (AF) since 2010. Despite a small cardioembolic risk score, CHA2DS2-Vasc=1 (Congestive heart failure, Hypertension, Age=75, Diabetes melitus, prior Stroke), the patient is effectively anticoagulated using acenocumarol. In December 2014, he showed signs of plantar transitory ischemia, for which he did not address the doctor. In early January 2015, he urgently presented at the hospital with left renal pain, caused by a renal infarction, diagnosed by computed tomography (CT) angiography. Left nephrectomy was performed with pathological confirmation. He was discharged with effective anticoagulation treatment. Within the next two weeks, he suffered a transitory ischemic event and a stroke, associated with right sided hemiparesis. On admission, AF was found and converted to sinus rhythm with effective anticoagulation - international normalized ratio (INR) of 2.12. Transthoracic echocardiography detected no pathological findings. Transesophageal echocardiography showed an expended left atrial appendage (LAA) with a slow blood flow (0.2 m÷s) and spontaneous echocontrast. Considering these clinical circumstances, surgical LAA suppression was decided on as a last therapeutic resort. Postoperative evolution was favorable; the patient is still free of ischemic events, one year post-intervention. Some morphological and hemodynamic characteristics of LAA may add additional thromboembolic risk factors, not included in scores. Removing them by surgical LAA suppression may decrease the risk of cardioembolic events. Intraoperative presence of thrombus makes it an indisputable proof.

Distal coronary embolization following acute myocardial infarction increases early infarct size and late left ventricular wall thinning in a porcine model

BACKGROUND

Distal coronary embolization (DCE) of thrombotic material occurs frequently during percutaneous interventions for acute myocardial infarction and can alter coronary flow grades. The significance of DCE on infarct size and myocardial function remains unsettled. The aims of this study were to evaluate the effects of DCE sufficient to cause no-reflow on infarct size, cardiac function and ventricular remodeling in a porcine acute myocardial infarction model.

METHODS AND RESULTS

Female Yorkshire pigs underwent 60 min balloon occlusion of the left anterior descending coronary artery followed by reperfusion and injection of either microthrombi (prepared from autologous porcine blood) sufficient to cause no-reflow (DCE), or saline (control). Animals were sacrificed at 3 h (n = 5), 3 days (n = 20) or 6 weeks (n = 20) post-AMI. Cardiovascular magnetic resonance (CMR), serum troponin-I, and cardiac gelatinase (MMP) and survival kinase (Akt) activities were assessed. At 3d, DCE increased infarct size (CMR: 18.8% vs. 14.5%, p = 0.04; serum troponin-I: 13.3 vs. 6.9 ng/uL, p < 0.05) and MMP-2 activity levels (0.81 vs. 0.49, p = 0.002), with reduced activation of Akt (0.06 versus 0.26, p = 0.02). At 6 weeks, there were no differences in infarct size, ventricular volume or ejection fraction between the two groups, although infarct transmurality (70% vs. 57%, p< 0.04) and ventricular thinning (percent change in mid anteroseptal wall thickness:-25.6% vs. 0.7%, p = 0.03) were significantly increased in the DCE group.

CONCLUSIONS

DCE increased early infarct size, but without affecting later infarct size, cardiac function or ventricular volumes. The significance of the later remodelling changes (ventricular thinning and transmurality) following DCE, possibly due to changes in MMP-2 activity and Akt activation, merits further study.

A fire death with a rare finding: anthracosis or soot embolism?

Charred human remains were found in the smoking ambers of a dying fire in an oil palm plantation in Selangor, Malaysia in the midnight of January 28, 2013. Investigations showed that palm fronds and rubber tires were used to light and sustain the blaze. At least four to five tires were estimated to be used based on the residual burnt metal wires at the site. The remains were brought to the Department of Forensic Medicine, Hospital Sungai Buloh, Selangor for post-mortem examination. Pre-autopsy imaging showed a fractured skull with presence of a bullet in the head. The body belonged to a male with unrecognizable facial features, pugilistic attitude, and reduced body size caused by fire damage with sparing of the posterior surface. A large fracture was present at the skull vault. An entry gunshot wound was observed on the left side of the body of mandible, which was associated with base of skull fracture. Heat-related fractures were also noted on the right side of the frontal bone. A projectile was retrieved from the right side of the occipital lobe. Further examination showed presence of soot and hyperaemic larynx, trachea, main bronchi, and oesophagus. Black spots measuring 1 to 2 mm were present on the surface and parenchyma of the heart, liver, pancreas and kidneys. Histopathology examination showed black particles within the vessels in the affected organs. We report this rare finding in a charred body and present a discussion based on published literature on this issue.

Increased visceral adipose tissue as a potential risk factor in patients with embolic stroke of undetermined source (ESUS)

PURPOSE

The etiology of an ischemic stroke remains undetermined in 20-35% of cases and many patients do not have any of the conventional risk factors. Increased visceral adipose tissue (VAT) is a suggested new risk factor for both carotid artery atherosclerosis (CAA) and atrial fibrillation (AF), but its role in the remaining stroke population is unknown. We assessed the amount of VAT in patients with embolic stroke of undetermined source (ESUS) after excluding major-risk cardioembolic sources, occlusive atherosclerosis, and lacunar stroke.

METHODS

Altogether 58 patients (mean age 57.7 ± 10.2 years, 44 men) with ischemic stroke of unknown etiology but without CAA, known AF or small vessel disease underwent computed tomography angiography and assessment of VAT. For comparison VAT values from three different reference populations were used. Conventional risk factors (smoking, hypertension, diabetes, increased total and LDL-cholesterol, decreased HDL-cholesterol) were also registered.

RESULTS

Mean VAT area was significantly higher in stroke patients (205 ± 103 cm2 for men and 168 ± 99 cm2 for women) compared to all reference populations (P < 0.01). 50% of male and 57% of female patients had an increased VAT area. In male patients, VAT was significantly higher despite similar body mass index (BMI). Increased VAT was more common than any of the conventional risk factors.

CONCLUSION

Increased VAT was found in over half of our patients with ESUS suggesting it may have a role in the pathogenesis of thromboembolism in this selected group of patients.

Pulmonary and coronary foreign particle embolism after central venous injection of liquid nutrition

A man was found dead in his nursing bed. The responsible assistant nurse explained that she had administered liquid nutrition (Isosource Energy Fibre 500 ml) via perfusion pump into the Hickman catheter, insisting that the Hickman catheter was a percutaneous endoscopic gastric tube. Autopsy findings were unspecific and could not reveal the cause of death. Histopathological examinations showed severe pulmonary foreign particle emboli, partially even emboli of the small coronary arteries. We present the pathological findings of the case in regard to the underlying pathophysiology.

Showers of emboli from a large aortic root thrombus

It is rare to find aortic root thrombi in the absence of aortic root aneurysm or extensive aortic atherosclerosis. Up to this date, only a few cases have been reported. The etiology has been mainly attributed to hypercoagulable disorders. Herein, we present a case of a large thrombus obliterating the aortic root in a patient presenting with acute abdominal pain and noted to have showers of emboli to the kidneys. Hypercoagulable workup failed to reveal any congenital or acquired clotting disorder. The thrombus was thought to have developed spontaneously, and was removed surgically. Two months later, however, she had an arterial clot in the left popliteal artery that was removed surgically. The patient was seen for follow-up three and six months later and was stable with no complaints. This case highlights the importance of considering the ascending aorta as a source in cases of systemic embolization. In addition, the different diagnostic options, management protocols, and potential complications are discussed.

Microembolism induces anhedonia but no detectable changes in white matter integrity in aged rats

Microvascular disease leads to alterations of cerebral vasculature including the formation of microembolic (ME) strokes. Though ME are associated with changes in mood and the severity and progression of cognitive decline, the effect of ME strokes on cerebral microstructure and its relationship to behavioral endpoints is unknown. Here, we used adult and aged male rats to test the hypotheses that ME lesions result in subtle changes to white and gray matter integrity as detected by high-throughput diffusion tensor imaging (DTI) and that these structural disruptions correspond to behavioral deficits. Two weeks post-surgery, aged animals showed depressive-like behaviors in the sucrose consumption test in the absence of altered cerebral diffusivity as assessed by ex-vivo DTI. Furthermore, DTI indices did not correlate with the degree of behavioral disruption in aged animals or in a subset of animals with observed tissue cavitation and subtle DTI alterations. Together, data suggest that behavioral deficits are not the result of damage to brain regions or white matter tracts, rather the activity of other systems may underlie functional disruption and recovery.

Relationship of thrombus characteristics to the incidence of angiographically visible distal embolization in patients with ST-segment elevation myocardial infarction treated with thrombus aspiration

OBJECTIVES

This study sought to investigate the association between pathological characteristics of aspirated intracoronary thrombi and the incidence of angiographically visible distal embolization (AVDE) during primary percutaneous coronary intervention (p-PCI) in patients with ST-segment elevation myocardial infarction (STEMI) treated with thrombus aspiration.

BACKGROUND

AVDE of atherosclerotic and thrombotic material has been shown to impair myocardial perfusion and contribute to poor clinical outcome in patients with STEMI. Recent studies have shown that thrombus composition and size are associated with the incidence of AVDE.

METHODS

Aspirated thrombi from 164 STEMI patients within 12 h of symptom onset were investigated immunohistochemically using antibodies against platelets, erythrocytes, and inflammatory cells.

RESULTS

The angiographic results showed that AVDE during p-PCI occurred in 22 (13.4%) patients. Pathological analysis revealed that thrombi from patients with AVDE had a greater erythrocyte-positive area (60 ± 15% vs. 43 ± 21%, p < 0.0005) and more myeloperoxidase-positive cells (943 ± 324 cells/mm(2) vs. 592 ± 419 cells/mm(2), p < 0.0005) than those from patients without AVDE. Thrombus size, quantified as the thrombus surface area, was positively correlated with the erythrocyte component (r = 0.362, p < 0.0001). Moreover, multivariate logistic analysis demonstrated that erythrocyte-positive area in the thrombi, glucose levels on admission, larger vessel diameter (≥ 3.5 mm), and pre-balloon dilation were independent predictors of the incidence of AVDE.

CONCLUSIONS

This study demonstrated that the erythrocyte-rich component of aspirated thrombi may be associated with the incidence of AVDE during p-PCI in patients with STEMI.

[Atrial myxoma: a histologically benign tumor with potentially serious manifestations]

Atrial myxoma is the most prevalent primary heart tumor. Although it is considered histologically benign, it may course with serious complications. We report the clinical case of a 35 years old man, previously asymptomatic, admitted due to an acute ischemia of the lower limbs, consequence of an embolic complication of a left atrial myxoma. We conclude with a brief review of the literature on the topic.

Multiple instances of peripheral artery emboli from occult primary small cell lung cancer

Most peripheral artery emboli originate in the heart, and systemic neoplastic emboli are infrequently associated with bronchogenic carcinoma. To our knowledge, there have been no reports of pulmonary vein infiltration by small cell lung cancer.We describe a highly unusual case of multiple instances of peripheral embolism as the first overt sign of occult primary small cell lung cancer. Tumor emboli infiltrated the pulmonary veins of a 62-year-old man who presented first with a transient ischemic attack and then with other ischemic symptoms. The uncommonly wide distribution of tumor emboli over a short time resulted in death.Improvements in diagnostic imaging have led to the early identification of relatively isolated small cell lung cancers. This patient's case underscores the importance of transesophageal echocardiography in detecting cardiac emboli when the cause of cerebral ischemic attack is unknown or if there might be multiple instances of arterial embolism. Computed tomography also has a role in the investigation of possible sources of emboli and unrecognized, asymptomatic embolization.

Calcified renal artery aneurism embolization in a solitary kidney

OBJECTIVE

To review presentation, diagnosis and treatment of renal artery aneurysms, a very uncommon disease.

METHODS

We report the case of a male with a calcified renal artery aneurysm in a solitary kidney.

RESULTS

Symptomatic effects may be hypertension, hematuria or flank pain. Arteriosclerosis and medial dysplasia are the most frequent causes and diagnosis is based on CT scan and angiography.

CONCLUSIONS

The renal artery aneurysm is a disease with low prevalence and there is no clear protocol for management. The number of cases has increased over the last decades and endovasculrar treatment is a good therapeutic option.

Prevention and treatment of microvascular obstruction-related myocardial injury and coronary no-reflow following percutaneous coronary intervention: a systematic approach

Microvascular obstruction (MVO) commonly occurs following percutaneous coronary interventions (PCI), may lead to myocardial injury, and is an independent predictor of adverse outcome. Severe MVO may manifest angiographically as reduced flow in the patent upstream epicardial arteries, a situation that is termed "no-reflow." Microvascular obstruction can be broadly categorized according to the duration of myocardial ischemia preceding PCI. In "interventional MVO" (e.g., elective PCI), obstruction typically involves myocardium that was not exposed to acute ischemia before PCI. Conversely "reperfusion MVO" (e.g., primary PCI for acute myocardial infarction) occurs within a myocardial territory that was ischemic before the coronary intervention. Interventional and reperfusion MVO have distinct pathophysiological mechanisms and may require individualized therapeutic approaches. Interventional MVO is triggered predominantly by downstream embolization of atherosclerotic material from the epicardial vessel wall into the distal microvasculature. Reperfusion MVO results from both distal embolization and ischemia-reperfusion injury within the subtended ischemic tissue. Management of MVO and no-reflow may be targeted at different levels: the epicardial artery, microvasculature, and tissue. The aim of the present report is to advocate a systematic approach to prevention and treatment of MVO in different clinical settings. Randomized clinical trials have studied strategies for prevention of MVO and no-reflow; however, the efficacy of measures for reversing MVO once no-reflow has been demonstrated angiographically is unclear. New approaches for prevention and treatment of MVO will require a better understanding of intracellular cardioprotective pathways such as the blockade of the mitochondrial permeability transition pore.

Neoplastic spread after trauma: natural death or manslaughter?

We report an unusual death of a seemingly healthy 26-year-old man due to diffuse metastasization of adrenal paraganglioma caused by rupture of the primitive tumour with subsequent massive haemorrhage after a relatively minor trauma. Our report describes the results of forensic investigation and discusses the possible mechanisms of metastasization.

[Cardiac mast cells accumulation and degranulation contribute to collagen deposition after coronary microembolization]

OBJECTIVE

To investigate potential pathophysiological role of cardiac mast cells accumulation and degranulation on the collagen deposition after coronary microembolization (CME).

METHODS

CME was induced in miniswine by selective infusion of 15X10(4) microspheres (diameter, 45 mum) into the left anterior descending artery groups (CME group, n=8). Some CME-induced animals were pretreated with the MC stabilizer tranilast (50 mg/kg, twice daily), beginning 2 weeks before CME and thereafter throughout the experimental period (CME +tranilast group, n=8), while some animals received tranilast without CME (tranilast group, n=8). Eight sham-operated animals without CME served as controls. After 30 days, the total number of MC and degranulating MCs and collagen deposition was assessed by histological and electronic microscopy studies.

RESULTS

The numbers of total and degranulating MCs and collagen volume fraction (CVF) at day 30 in CME group were significantly higher than those in controls (P <0.01). Treatment with tranilast significantly reduced the numbers of total and degranulating MCs and CVF at day 30 (all P <0.01). There was a significant positive correlation of the CVF with the number of total MCs (r=0.91, P <0.001) and degranulating MCs (r=0.92, P <0.001) over the CME myocardium.

CONCLUSION

MCs accumulation and degranulating contribute to myocardial fibrosis collagen deposition.

Left main coronary artery embolus: unusual presentation of papillary fibroelastoma of the aortic valve

The usual cause of left main coronary artery obstruction is atherosclerotic occlusion resulting from plaque rupture and subsequent thrombus formation. In previously reported cases, tumor embolization into the coronary arteries caused sudden death and was detected only at autopsy. Herein, we report an unusual presentation of cardiac papillary fibroelastoma of the aortic valve in a 62-year-old man. The fibroelastoma caused a left main coronary artery embolus and symptoms of acute coronary syndrome. The fibroelastoma was successfully excised during a valve-sparing surgical procedure. We believe that this is the 1st report of tumor embolization to the left main coronary artery--and in a living patient.

Tumor embolus due to uterine cancer

BACKGROUND

Although the majority of arterial emboli are thrombi originating from the heart, emboli of other origin do occur. The purpose of this paper is to report a case of tumor embolus of a brachial artery.

CASE REPORT

A 64-year-old woman was referred for vascular surgery due to acute right upper-limb ischemia. ECG showed sinus rhythm without ischemic changes. Four years earlier the patient had undergone total hysterectomy with bilateral adnexotomy for endometrial adenocarcinoma with subsequent radiotherapy. Emergency embolectomy under local anesthesia was performed with uneventful recovery. Because of an atypical appearance resembling fatty tissue, the embolic material was sent for microscopic examination that revealed carcinoma cells. Chest X-ray and CT-guided biopsy showed previously unknown pulmonary metastasis. In spite of chemotherapy, the patient died one year later due to progression of the neoplastic disease. The literature and common features of tumor embolus are reviewed. This may be the first reported case of tumor peripheral arterial embolus caused by endometrial adenocarcinoma

CONCLUSIONS

Although tumor emboli are a rarely described cause of acute limb ischemia, pathological examination of the embolic material seems to be indicated, especially in patients with an unknown source of emboli and in every case of an atypical appearance.

Magnetic resonance imaging of a hypereosinophilic endocarditis with apical thrombotic obliteration in Churg-Strauss syndrome complicated with acute abdominal aortic embolic occlusion

Churg-Strauss syndrome can be associated with Loeffler-like eosinophilic endocarditis. We report a case of a young woman in which the diagnosis of Churg-Strauss syndrome was made subsequently to the magnetic resonance demonstration of eosinophilic endocarditis associated to left ventricle apical thrombosis. In our report, this rare condition evolved in an unusual complication: the embolic migration of the left ventricle apical thrombus in the abdominal aorta as showed by multi-detector-computed-tomography angiography.

Analysis of particulate debris after superficial femoral artery atherectomy

PURPOSE

To evaluate the occurrence, size and composition of embolized debris captured during routine directional atherectomy using the SilverHawk device.

METHODS

15 consecutive eligible patients with a nonocclusive superficial femoral artery (SFA) were enrolled. Patients were included if they were > 18 years of age and had > or = 70% stenosis in the SFA. All lesions underwent plaque excision with the SilverHawk atherectomy device. A FilterWire EZ was used for distal protection and retrieval of embolized material. Specimens were collected separately from the filter basket and the SilverHawk atherectomy device's nosecone and were studied by a pathologist for number, size and composition.

RESULTS

Visible debris captured in the filter was found in the majority of patients 14/15 (93%). Clinically-significant debris was found in 7/15 (47%) patients. The proportion of captured debris ranged from 0.1-0.4 cm. Microscopy revealed that the shaved particles consisted predominantly of collagen, fibrin, lipid-laden macrophages, cholesterol and calcium. Analysis of the embolized material revealed a different composition, mostly consisting of collagen with fibrosis, cholesterol and macrophages.

CONCLUSION

In this single-center comparative study we have shown that during SilverHawk atherectomy of SFA lesions, distal embolization is universal. The debris captured in the filter is different in overall composition from the captured material in the nosecone of the SilverHawk device. Debris large enough to cause clinically-significant embolization, no-reflow and ischemia following SFA interventions occurred in nearly 50% of cases.

Cardiac papillary fibroelastoma as a cause of embolic stroke: ultrasound and histopathological characteristics

Although a cardiac papillary fibroelastoma is a benign cardiac tumor, it can cause severe embolic complications. A 51-year-old man presented with an ischemic stroke in the right middle cerebral artery territory. Transesophageal echocardiography revealed a small mobile tumor on the mitral valve as the only detectable source of emboli to the brain. On histology, the tumor was diagnosed as a papillary fibroelastoma. In this paper, the detailed characteristics of the tumor on ultrasound and histopathology are documented. In patients with cryptogenic stroke, transesophageal echocardiography should be done to rule out such an unusual emboligenic heart disease.

Concurrent pheochromocytoma, ventricular tachycardia, left ventricular thrombus, and systemic embolization

An obese 43-year-old female with a right adrenal pheochromocytoma is described. The clinical manifestations of this case included ventricular tachycardia, left ventricular thrombus, and elevation of serum myocardial enzymes. During the hospitalization, the left ventricular thrombus was detached, leading to renal infarction and embolic occlusion of the femoral arteries bilaterally.