Subacute Infarction Research Articles

P6171Effects on myocardial remodeling with ranolazine in subacute mycoardial infarction

P6171Effects on myocardial remodeling with ranolazine in subacute mycoardial infarction

EBV driven natural killer cell disease of the central nervous system presenting as subacute cognitive decline

Brain biopsy in patients presenting with subacute encephalopathy is never straightforward, and only undertaken when a ‘treatable condition’ is a realistic possibility.This 63year old right handed, immunocompetent Caucasian woman presented with an 8month history of rapidly progressive right-sided hearing impairment, a 4month history of intermittent headaches, tinnitus, ‘dizziness’, dysphagia, nausea and vomiting, with the subsequent evolution of progressive gait ataxia and a subacute global encephalopathy. The possibility of CJD was raised. Brain biopsy was carried out. Western blot for prion protein was negative. She died 9days later and autopsy brain examination confirmed widespread subacute infarction due to an EBV positive atypical NK/T-cell infiltrate with positivity for CD3, CD56, granzyme B, perforin and EBER with absence of CD4, CD5 and CD8 expression. Molecular studies for T-cell clonality were attempted but failed due to insufficient DNA quality. Serology was consistent with past EBV infection (EBV VCA and EBNA IgG Positive). There was no evidence of disease outside the CNS. Primary central nervous system NK/T-cell lymphoma is extremely rare. The rare reported cases all present with a discrete intracranial mass, unlike the diffuse infiltrative pattern in this case. Whilst the diffuse interstitial pattern is reminiscent of chronic active EBV infection (CAEBV) seen in other organ systems such as the liver and bone marrow, the clinical presentation and epidemiologic profile are not typical for CAEBV.

Slow antegrade excitation and delayed retrograde activation through an "inexcitable zone": A basis for arrhythmia formation in infarcted myocardium ex vivo.

The electrophysiologic mechanism for rate-dependent PVBs associated with double potentials (DPs) was investigated in infarcted canine hearts using bipolar and intracellular microelectrode recordings. Dogs exhibiting rate-related ventricular ectopic beats (coupling interval, 390 ± 54 milliseconds) during sinus rhythm or atrial pacing were studied 4-5 days (N = 63) or 25 days (N = 16) following anterior descending coronary artery ligation. Sites of DP and rate-dependent arrhythmia formation were identified in vivo using bipolar recordings for subsequent ex vivo studies. Rate-dependent conduction delays with increasing duration isoelectric intervals representing very slow conduction were observed at sites of DP formation, frequently provoking both manifest and concealed reentry (non-stimulated beats) over a narrow range of paced cycle lengths. Both slow antegrade and retrograde activation across an inexcitable gap (reflection) were integral components of extrasystole formation. Retrograde reflection to a region of very slow conduction (mid-potential) during antegrade activation was routinely observed at 4-5 days (42 of 63 preparations, 67%) and 25 days (22 of 26 preparations, 85%) postcoronary artery ligation. Reflection and premature re-activation of the proximal site was then observed in 6 of 63 (9%), and 3 of 26 preparations (12%). The present experiments demonstrate DP formation and rate-dependent constant-coupled late epicardial premature beats in infarcted dog hearts. Microelectrode recordings at DP sites demonstrating prolonged isoelectric intervals display very slow conduction preceding distal activation and "reentrant" re-activation of more proximal sites, representing reflection as an arrhythmia mechanism in ischemically injured epicardium during subacute myocardial infarction.

Temperature-corrected postmortem 3-T MR quantification of histopathological early acute and chronic myocardial infarction: a feasibility study.

The goal of the present study was to evaluate if quantitative postmortem cardiac 3-T magnetic resonance (QPMCMR) T1 and T2 relaxation times and proton density values of histopathological early acute and chronic myocardial infarction differ to the quantitative values of non-pathologic myocardium and other histopathological age stages of myocardial infarction with regard to varying corpse temperatures. In 60 forensic corpses (25 female, 35 male), a cardiac 3-T MR quantification sequence was performed prior to autopsy and cardiac dissection. Core body temperature was assessed during MR examinations. Focal myocardial signal alterations in synthetically generated MR images were measured for their T1, T2, and proton density (PD) values. Locations of signal alteration measurements in PMCMR were targeted at heart dissection, and myocardial tissue specimens were taken for histologic examinations. Quantified signal alterations in QPMCMR were correlated to their according histologic age stage of myocardial infarction, and quantitative values were corrected for a temperature of 37°C. In QPMCMR, 49 myocardial signal alterations were detected in 43 of 60 investigated hearts. Signal alterations were diagnosed histologically as early acute (n=16), acute (n=10), acute with hemorrhagic component (n=9), subacute (n=3), and chronic (n=11) myocardial infarction. Statistical analysis revealed that based on their temperature-corrected quantitative T1, T2, and PD values, a significant difference between early acute, acute, and chronic myocardial infarction can be determined. It can be concluded that quantitative 3-T postmortem cardiac MR based on temperature-corrected T1, T2, and PD values may be feasible for pre-autopsy diagnosis of histopathological early acute, acute, and chronic myocardial infarction, which needs to be confirmed histologically.

Mitral valve vegetation diagnosed with oesophageal ultrasound with bronchoscope (EUS-B)

Oesophageal ultrasound with bronchoscope (EUS-B) is designed to evaluate mediastinal structures. We describe a case of a 78-year-old woman who presented with altered mental status for 2 weeks. CT head...

Abstract 526: Thromboembolic Phenomenon in a Patient With Unexplained Transverse Aortic Thrombus

A 55 year-old Caucasian male, with no known past medical history, presented to the ER complaining of left upper extremity pain with finger tingling and difficulty speaking that started 8 hours before presentation, while driving his car. In the ER, physical exam was remarkable for mild expressive aphasia with difficulty finding words. His left arm was tender without any edema or erythema and normal range of motion. His left hand fingertips appeared cyanotic ( Picture 1) , however his radial and ulnar pulses were intact bilaterally. Laboratory evaluation revealed a platelet count 1,416,000/mcl, and normal PT/INR and PTT. CT of the brain showed no intracranial bleed. MRI of the brain showed multiple small sub-acute infarcts in the left occipital lobe, left basal ganglia and bilateral cerebellar hemispheres suggesting a shower of emboli. Because of a concern for possible aortic dissection by the ER physician, a CT angiogram of the chest was done. It revealed a large filling defect (up to 3.1 cm) in the distal transverse thoracic aorta, consistent with non-occlusive thrombus adjacent to the origin of the left subclavian artery ( Picture 2) . Subsequently, TEE was done and again showed a large mobile thrombus attached to the inferior posterior wall of the transverse thoracic aorta ( Picture 3) . Given the extremely mobile and large sized thrombus, with high risk for further embolization, the patient underwent surgery with excision of the aortic thrombus ( Picture 4) . The patient had an uncomplicated post-operative course and warfarin was started empirically post-operatively. Further Hematology work up was suggestive of Essential Thrombocytosis. The patient was started on hydroxyurea. On his 3-week follow up appointment, his platelet count decreased to 202,000/mcl. Anti-coagulation was continued for 3 months. His neurologic symptoms significantly improved with only mild residual left hand finger tips claudication which resolved by 1 month post discharge.

Detection of crossed cerebellar diaschisis in hyperacute ischemic stroke using arterial spin-labeled MR imaging.

Background and purposeArterial spin-labeling (ASL) was recently introduced as a noninvasive method to evaluate cerebral hemodynamics. The purposes of this study were to assess the ability of ASL imaging to detect crossed cerebellar diaschisis (CCD) in patients with their first unilateral supratentorial hyperacute stroke and to identify imaging or clinical factors significantly associated with CCD.Materials and methodsWe reviewed 204 consecutive patients who underwent MRI less than 8 hours after the onset of stroke symptoms. The inclusion criteria were supratentorial abnormality in diffusion-weighted images in the absence of a cerebellar or brain stem lesion, bilateral supratentorial infarction, subacute or chronic infarction, and MR angiography showing vertebrobasilar system disease. For qualitative analysis, asymmetric cerebellar hypoperfusion in ASL images was categorized into 3 grades. Quantitative analysis was performed to calculate the asymmetric index (AI). The patients’ demographic and clinical features and outcomes were recorded. Univariate and multivariate analyses were also performed.ResultsA total of 32 patients met the inclusion criteria, and 24 (75%) presented CCD. Univariate analyses revealed more frequent arterial occlusions, higher diffusion-weighted imaging (DWI) lesion volumes and higher initial NIHSS and mRS scores in the CCD-positive group compared with the CCD-negative group (all p < .05). The presence of arterial occlusion and the initial mRS scores were related with the AI (all p < .05). Multivariate analyses revealed that arterial occlusion and the initial mRS scores were significantly associated with CCD and AI.ConclusionASL imaging could detect CCD in 75% of patients with hyperacute infarction. We found that CCD was more prevalent in patients with arterial occlusion, larger ischemic brain volumes, and higher initial NIHSS and mRS scores. In particular, vessel occlusion and initial mRS score appeared to be significantly related with CCD pathophysiology in the hyperacute stage.

Identifying ischemic stroke associated with cancer: a multiple model derived from a case-control analysis.

Ischemic stroke in patients with cancer is thought to be associated with a worse prognosis and might be the initial symptom of an unknown malignancy. However, diagnostic algorithms to reliably identify cancer-associated stroke have not been developed. In this retrospective single-centre analysis, 68 patients with ischemic stroke and an active solid malignancy were identified. Neurological assessment and outcome, cardiovascular risk factors, neuroimaging studies as well as laboratory findings were compared to 68 age- and sex-matched control subjects with ischemic stroke without diagnosis of cancer. Lung, pancreatic and renal cancer showed increased prevalences compared to those of the general population in Germany. Diagnosis of cancer was most often made within the 12months preceding (32.4%) or during the diagnostic work-up for stroke (17.7%). Cancer-associated stroke was characterized by a more severe clinical deficit, frequent clinical deterioration (13.2 vs. 1.5%) or death (25 vs. 4.4%). Ischemic lesions often involved multiple territories (51.6 vs. 12.7%), more often with co-existing subacute and acute infarctions in imaging studies (54.8 vs. 11.1%). Patients with cancer had significantly higher levels of C-reactive protein, relative granulocytosis and serum lactate dehydrogenase activity. Using receiver operating characteristics-based multiple analysis, we developed a model using these parameters which detected cancer-associated stroke with a sensitivity of 75% and specificity of 95%. Our analysis suggests that a multiple algorithm combining the number of territories involved and laboratory signs of inflammation and cell turnover might identify patients with stroke suffering from previously unknown malignancy.

Abstract TMP87: Early Surgery for Infective Endocarditis with Stroke Does Not Increase Post-operative Neurological Complications: What are We Waiting For?

Introduction: Ischemic and hemorrhagic stroke often complicate infective endocarditis (IE). Optimal timing of surgical intervention for IE with stroke remains controversial. We compared neurological outcomes of early and delayed valve surgery for IE complicated by stroke. Methods: We reviewed 73 patients with acute IE by Duke Criteria who underwent brain imaging (CT, MRI, or cerebral angiogram) before valve operations between December 2014 and August 2016. Date of IE diagnosis was defined as date of antibiotic initiation. Early surgery was defined as valve replacement ≤14 days from date of IE diagnosis and delayed surgery as &gt;14 days. Neurological complication is defined as delirium &gt;72 hours after extubation and cessation of sedation, new ischemic or hemorrhagic stroke. Results: Among 73 patients who underwent valve replacement surgery, 71 had evidence of stroke on imaging: 54 patients with acute or subacute ischemic infarct, 9 patients with evidence of intracerebral hemorrhage, and 8 patients with subarachnoid hemorrhage. The median time from IE diagnosis to surgery was 9 days. Forty patients had early surgery, and 33 patients had late surgery. Early surgery group had fewer patients with history of ischemic stroke (55% vs 79%, p=0.033), fewer acute or subacute infarcts on imaging (63% vs 88% p=0.016), but more native valve infections (73% vs 45%, p=0.018). The incidence of post-operative stroke was similar between both groups (2.5% vs 9%, p=0.32). In the delayed group, ischemic strokes occurred in 4 patients awaiting surgery. Hypertension and diabetes mellitus were associated with post-operative neurological complications (p&lt;0.05), but pre-operative stroke on imaging was not. Conclusion: In IE patients with acute stroke, early surgery does not appear to increase post-operative neurological complications.

Surgical Treatment of Idiopathic Multiple Pulmonary Arteriovenous Malformation Identified at the Onset of Cerebral Infarction: A Case Report

Pulmonary arteriovenous malformation (PAVM), which is asymptomatic in most cases, is often identified in patients with central nervous system disorders such as brain abscesses and/or cerebral infarctions. We have reported a patient with idiopathic multiple PAVM identified at the onset of cerebral infarction. A 69-year-old woman visited the Department of Neuropathic Internal Medicine at our hospital with chief complaints of numbness in her left hand and a feeling of weakness. The patient was given a diagnosis of subacute cerebral infarction. Multiple old lacunar infarctions were also observed in the deep white matter of the left frontal lobe. Chest computed tomography showed multiple nodular structures, mainly in the right lower lung field (S8), as well as continuous arteries and veins at the site; thus, the patient was finally diagnosed with multiple PAVM. Right lower thoracoscopic lobectomy was performed, as is typical surgical practice in such cases. The patient had a favorable postoperative course, and had no recurrence of cerebral infarction. Although the patient’s lesions were mainly restricted to S8, the fact that there were multiple lesions deemed a lobectomy as the appropriate course of treatment. This case emphasizes that attention should be paid to cases of multiple PAVM since cerebral infarction may arise from the disease.

Posterior atlantoaxial fusion using a C2 transverse foramen-penetrating screw: A technical note.

Background:Although recent development of screw instrumentation techniques for rigid fixation of the atlantoaxial joint has increased surgical options, patients in whom screws of any type cannot be safely placed are sometimes encountered. We present a unique surgical technique for C1-2 transarticular screw placement utilizing a novel trajectory.Methods:A 35-year-old male with a history of Down's syndrome and cognitive dysfunction with hyperkinesis spontaneously developed rapid onset of tetraparesis and gait disturbance. Radiographs of the cervical spine revealed atlantoaxial subluxation (AAS) that could not be reduced. Computed tomography (CT) of the head showed multiple subacute cerebral infarctions in the territory of the right vertebral artery (VA). Three-dimensional CT angiography of the craniovertebral junction additionally confirmed right VA occlusion at the C2/3 level, a left C2 origin of the posterior inferior cerebellar artery, and hypoplasia of the bilateral C2 pedicles/C2 lamina. Because traditional screw-placement was not feasible, we performed a unique atlantoaxial fusion utilizing a C2 transverse foramen-penetrating screw with iliac bone grafting performed under neuronavigation.Results:The postoperative course was uneventful, and the patient regained the ability to ambulate, returning to his previous level of function. The CT of the cervical spine 12 months postoperatively showed rigid bony C1-C2 fusion, without recurrence of stroke.Conclusion:We introduced a novel C1-C2 transarticular screw-placement technique in which the trajectory went through the ipsilateral VA foramen due to already extent VA occlusion.

Myelin phagocytosis by astrocytes after myelin damage promotes lesion pathology.

Astrocytes are key players in the pathology of multiple sclerosis and can assume beneficial and detrimental roles during lesion development. The triggers and timing of the different astroglial responses in acute lesions remain unclear. Astrocytes in acute multiple sclerosis lesions have been shown previously to contain myelin debris, although its significance has not been examined. We hypothesized that myelin phagocytosis by astrocytes is an early event during lesion formation and leads to astroglial immune responses. We examined multiple sclerosis lesions and other central nervous system pathologies with prominent myelin injury, namely, progressive multifocal leukoencephalopathy, metachromatic leukodystrophy and subacute infarct. In all conditions, we found that myelin debris was present in most astrocytes at sites of acute myelin breakdown, indicating that astroglial myelin phagocytosis is an early and prominent feature. Functionally, myelin debris was taken up by astrocytes through receptor-mediated endocytosis and resulted in astroglial NF-κB activation and secretion of chemokines. These in vitro results in rats were validated in human disease where myelin-positive hypertrophic astrocytes showed increased nuclear localization of NF-κB and elevated chemokine expression compared to myelin-negative, reactive astrocytes. Thus, our data suggest that myelin uptake is an early response of astrocytes in diseases with prominent myelin injury that results in recruitment of immune cells. This first line response of astrocytes to myelin injury may exert beneficial or detrimental effects on the lesion pathology, depending on the inflammatory context. Modulating this response might be of therapeutic relevance in multiple sclerosis and other demyelinating conditions.

Intra-arterial Infusion of Autologous Bone Marrow Mononuclear Stem Cells in Subacute Ischemic Stroke Patients.

Based on many preclinical and small clinical trials, stem cells can help stroke patient with the possibility of replacing the cells and supporting the remaining cells. The aim of this study was to evaluate the safety and feasibility of bone marrow mononuclear (BMMN) stem cell transplantation in subacute ischemic stroke patients. Thirty-nine (n = 39) patients with subacute ischemic cerebral infarct due to large artery occlusion in the middle cerebral artery (MCA) territory were recruited. They were distributed into two groups: first group (n = 21) served as an experimental group, which received intra-arterial (IA) mononuclear stem cells (bone marrow-derived mononuclear cell), while the other group (n = 18) served as a control group. All the patients were evaluated clinically by National Institutes of Health Stroke Scale, modified Rankin Scale, Barthel Index, modified and standardized Arabic version of the Comprehensive Aphasia Test, and radiological for 12 months. The stem cell-treated group showed better improvement, but it was not significant when compared with the non-treated group. The volume of infarction changes at the end of the study was non-significant between both the groups. There was no, or minimal, adverse reactions in stem cell-treated group. The study results suggest that autologous BMMN stem cell IA transplantation in subacute MCA ischemic stroke patients is safe with very minimal hazards, but no significant improvement of motor, language disturbance, or infarction volume was detected in stem cell-treated group compared with the non-treated group.

Left ventricular wall rupture due to subacute myocardial infarction and severe aortic regurgitation of the bioprosthetic aortic valve

Left ventricular wall rupture due to subacute myocardial infarction and severe aortic regurgitation of the bioprosthetic aortic valve

Clinical Reasoning: A complicated case of MELAS

A 48-year-old right-hand-dominant woman presented to the emergency department with sudden onset of visual loss of her left visual field. She had a complicated medical history—end-stage renal disease requiring renal transplant 6 years prior to presentation secondary to biopsy-proven focal segmental glomerulosclerosis (FSGS), coronary artery disease, left atrial enlargement due to pulmonic stenosis, progressive sensorineural hearing loss 10 years prior and subsequent placement of a right cochlear implant, hypertension, and type 2 diabetes mellitus for the last year. At presentation, the patient's medications included cotrimoxazole prophylaxis, mycophenolate mofetil, tacrolimus, insulin, and folic acid. On examination, she was of short stature and had a low-grade fever and a left homonymous hemianopsia (L-HH). Within the next 3 weeks, she subsequently developed further visual disturbance to the point of being cortically blind in addition to new left upper extremity paresthesias. Initial CT head scan showed a subacute right occipital infarct and bilateral basal ganglia calcification. Subsequent CT imaging done 3 weeks later demonstrated interval development of new left temporoparietal and left occipital infarcts (figure, A). CT angiogram showed intracranial stenoses affecting basilar artery, both posterior cerebral arteries, and to a lesser degree bilateral anterior cerebral arteries and middle cerebral arteries, suggestive of possible atherosclerosis, but were not believed to be hemodynamically significant (figure, B). Due to her cochlear implant, significant streak artifact affected the interpretation of her CT scans and precluded her from obtaining an MRI.

Erratum to: Transcatheter aortic valve implantation and internal carotid artery stenting in a 74-year-old female patient

This article presents the case of a combined intervention for transcatheter aortic valve implantation (TAVI) and stenting of the internal carotid artery. Due to severe aortic stenosis and a subacute infarction in the middle cerebral artery territory, with neurological instability while hypotensive and cardiac failure while hypertensive, it was decided to carry out the intervention as a single combined procedure. An open surgical intervention was decided against because of the high peri-interventional mortality risk. The intervention was complication-free but a slight subarachnoid hemorrhage occurred in the postinterventional period. It was unclear if the bleeding was the result of cerebral hyperperfusion poststenting, if bleeding in an ischemic region was favored by post-TAVI hyperemia and whether the outcome would have been better with two separate interventions.

Staphylococcus caprae native mitral valve infective endocarditis

Introduction:Staphylococcus caprae is a rare cause of infective endocarditis. Here, we report a case involving the native mitral valve in the absence of an implantable cardiac electronic device.Case presentation:A 76-year-old man presented with a 2 week history of confusion and pyrexia. His past medical history included an open reduction and internal fixation of a humeral fracture 17 years previously, which remained non-united despite further revision 4 years later. There was no history of immunocompromise or farm-animal contact. Two sets of blood culture bottles, more than 12 h apart, were positive for S. caprae. Trans-thoracic echocardiography revealed a 1×1.2 cm vegetation on the mitral valve, with moderate mitral regurgitation. Due to ongoing confusion, he had a magnetic resonance imaging brain scan, which showed a subacute small vessel infarct consistent with a thromboembolic source. A humeral SPECT-CT (single-photon emission computerized tomography-computerized tomography) scan showed no clear evidence of acute osteomyelitis. Surgical vegetectomy and mitral-valve repair were considered to reduce the risk of further systemic embolism and progressive valve infection. However, the potential risks of surgery to this patient led to a decision to pursue a cure with antibiotic therapy alone. He remained well 3 months after discharge, with repeat echocardiography demonstrating a reduction in the size of the vegetation (0.9 cm).Conclusion:Management of this infection was challenging due to its rarity and its unclear progression, complicated by the dilemma surrounding surgical intervention in a patient with a complex medical background.

Evaluation of mean diffusion and kurtosis MRI mismatch in subacute ischemic stroke: Comparison with NIHSS score

Neurological deterioration (ND) is a devastating complication following ischemic stroke. This study aimed to identify the differences in lesion characteristics in subacute ischemic stroke patients with and without ND using diffusional kurtosis imaging (DKI), as well as to confirm the responsible lesions that may lead to ND, as assessed by the National Institutes of Health Stroke Scale (NIHSS) score. Seventy-nine patients with subacute cerebral infarction were allocated to the ND (−) and ND (+) groups according to the NIHSS score and lesion number. The mean diffusion (MD) lesions were significantly larger than the mean kurtosis (MK) deficits in the ND (+) group (P<0.05); however, there was no significant difference in the ND (−) group (P>0.05). The MD and MK in the lesion recovered to normal levels over time; however, the recovery trends in the ND (+) group were substantially slower than the ND (−) group. The differences between the two groups were only significant regarding the MK (p<0.05). Furthermore, multiple infarction lesions exhibited good consistency in the ND (−) group, but were non-homogeneous in the ND (+) group. To the best of our knowledge, this is the first study to demonstrate that a significant MD/MK mismatch and heterogeneity of multiple ischemic lesions on MK in subacute ischemic stroke may represent a new expansion of an ischemic lesion or acute reinfarction, which is closely related to ND.

Coronary thrombus in 34-year-old female patient with 4G/4G polymorphism in the PAI-1 gene

Genetic factors and hypofibrinolytic state may contribute to the likelihood of developing in myocardial infarction (MI) in young women rather than traditional risk factors. High plasminogen-activator inhibitor-1 (PAI-1) level and PAI-1 gene polymorphism have been shown to be associated with thrombotic events such as myocardial infarction, deep venous thrombosis, and stroke. We determined 4G/4G polymorphism in a 34-year-old female patient with subacute anterior myocardial infarction and coronary thrombus in left anterior descending artery on coronary angiogram.

Seizure and Fever

Dr. Jonathan Sonis: Today's case is that of a 60-year-old man transferred from an outside hospital to our emergency department (ED) with status epilepticus and noncontrast head computer tomography (CT) findings concerning for a subacute right temporal lobe infarct.