1
|
Seitz A, Merkler AE. Time to Think About Myocardial Infarction in Acute Ischemic Stroke. JAMA Neurol 2024; 81:691-692. [PMID: 38829666 DOI: 10.1001/jamaneurol.2024.1547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Affiliation(s)
- Alison Seitz
- Clinical and Translational Neuroscience Unit, Department of Neurology, Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York
| | - Alexander E Merkler
- Clinical and Translational Neuroscience Unit, Department of Neurology, Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York
| |
Collapse
|
2
|
Thorp EB, Flanagan ME, Popko B, DeBerge M. Resolving inflammatory links between myocardial infarction and vascular dementia. Semin Immunol 2022; 59:101600. [PMID: 35227567 PMCID: PMC10234261 DOI: 10.1016/j.smim.2022.101600] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 02/07/2022] [Accepted: 02/15/2022] [Indexed: 01/15/2023]
Abstract
Myocardial infarction is associated with increased risk for vascular dementia. In both myocardial infarction and vascular dementia, there is evidence that elevated inflammatory biomarkers are associated with worsened clinical outcomes. Myocardial infarction leads to a systemic inflammatory response, which may contribute to recruitment or activation of myeloid cells, including monocytes, microglia, and perivascular macrophages, within the central nervous system. However, our understanding of the causative roles for these cells linking cardiac injury to the development and progression of dementia is incomplete. Herein, we provide an overview of inflammatory cellular and molecular links between myocardial infarction and vascular dementia and discuss strategies to resolve inflammation after myocardial infarction to limit neurovascular injury.
Collapse
Affiliation(s)
- Edward B Thorp
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States.
| | - Margaret E Flanagan
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States; Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States
| | - Brian Popko
- Department of Neurology, Division of Multiple Sclerosis and Neuroimmunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States
| | - Matthew DeBerge
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States.
| |
Collapse
|
3
|
Matsumoto M, Takei N, Mineki T, Yahata T, Oiwa K. Anticoagulant therapy with dual antiplatelet for left ventricular thrombus following acute myocardial infarction. J Cardiol Cases 2020; 22:114-116. [DOI: 10.1016/j.jccase.2020.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 04/30/2020] [Accepted: 05/08/2020] [Indexed: 11/28/2022] Open
|
4
|
Delgado-Montero A, Martinez-Legazpi P, Desco MM, Rodríguez-Pérez D, Díaz-Otero F, Rossini L, Pérez del Villar C, Rodríguez-González E, Chazo C, Benito Y, Flores O, Antoranz JC, Fernández-Avilés F, del Álamo JC, Bermejo J. Blood Stasis Imaging Predicts Cerebral Microembolism during Acute Myocardial Infarction. J Am Soc Echocardiogr 2020; 33:389-398. [DOI: 10.1016/j.echo.2019.09.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 09/25/2019] [Accepted: 09/25/2019] [Indexed: 10/25/2022]
|
5
|
Kao PH, Chou PY, Hsu PC, Huang TC. Resolution of left ventricular thrombus by edoxaban after failed treatment with warfarin overdose: A case report. Medicine (Baltimore) 2019; 98:e14065. [PMID: 30633209 PMCID: PMC6336554 DOI: 10.1097/md.0000000000014065] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
RATIONALE Although novel oral-anticoagulants are widely used in patients with atrial fibrillation (AF) for stroke prevention, there was only limited evidence for their use in left ventricular (LV) thrombus. PATIENT CONCERNS A 41-year-old man who presented with acute onset of right-hand clumsiness and aphasia even under high international normalized ratio (INR: 7.64) from warfarin use. He was previously treated with warfarin for the LV thrombus and non-valvular AF. Brain magnetic resonance imaging (MRI) showed multiple acute infarction in the cortex of the bilateral frontal lobes, left parietal lobe, and bilateral central semiovale, which highly suggested embolic stroke. DIAGNOSIS The repeated transthoracic echocardiogram still revealed LV thrombus (1.27 × 0.90 cm), which failed to respond to warfarin therapy. INTERVENTIONS Due to acute infarctions occurred under supratherapeutic range of INR, we switched warfarin to edoxaban (dose: 60 mg/day) after INR decreased to less than 2. OUTCOMES The thrombus disappeared after receiving edoxaban for 23 days, and no more recurrent stroke was noted for more than 6 months. LESSONS This is the first case demonstrates that while facing ineffective treatment of warfarin for LV thrombus, edoxaban could be safely and effectively used under this situation.
Collapse
Affiliation(s)
- Pei-Heng Kao
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital
| | - Ping-Yin Chou
- Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Po-Chao Hsu
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital
- Department of Internal Medicine, Faculty of Medicine, College of Medicine, Kaohsiung Medical University
| | - Tien-Chi Huang
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital
| |
Collapse
|
6
|
Cerebral Gaseous Microemboli are Detectable During Continuous Venovenous Hemodialysis in Critically Ill Patients: An Observational Pilot Study. J Neurosurg Anesthesiol 2018; 29:236-242. [PMID: 26998647 DOI: 10.1097/ana.0000000000000296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Continuous venovenous hemodialysis (CVVHD) may generate microemboli that cross the pulmonary circulation and reach the brain. The aim of the present study was to quantify (load per time interval) and qualify (gaseous vs. solid) cerebral microemboli (CME), detected as high-intensity transient signals, using transcranial Doppler ultrasound. MATERIALS AND METHODS Twenty intensive care unit (ICU group) patients requiring CVVHD were examined. CME were recorded in both middle cerebral arteries for 30 minutes during CVVHD and a CVVHD-free interval. Twenty additional patients, hospitalized for orthopedic surgery, served as a non-ICU control group. Statistical analyses were performed using the Mann-Whitney U test or the Wilcoxon matched-pairs signed-rank test, followed by Bonferroni corrections for multiple comparisons. RESULTS In the non-ICU group, 48 (14.5-169.5) (median [range]) gaseous CME were detected. In the ICU group, the 67.5 (14.5-588.5) gaseous CME detected during the CVVHD-free interval increased 5-fold to 344.5 (59-1019) during CVVHD (P<0.001). The number of solid CME was low in all groups (non-ICU group: 2 [0-5.5]; ICU group CVVHD-free interval: 1.5 [0-14.25]; ICU group during CVVHD: 7 [3-27.75]). CONCLUSIONS This observational pilot study shows that CVVHD was associated with a higher gaseous but not solid CME burden in critically ill patients. Although the differentiation between gaseous and solid CME remains challenging, our finding may support the hypothesis of microbubble generation in the CVVHD circuit and its transpulmonary translocation toward the intracranial circulation. Importantly, the impact of gaseous and solid CME generated during CVVHD on brain integrity of critically ill patients currently remains unknown and is highly debated.
Collapse
|
7
|
Prognostic Role of Microembolic Signals After Endovascular Treatment in Anterior Circulation Ischemic Stroke Patients. World Neurosurg 2018; 110:e882-e889. [DOI: 10.1016/j.wneu.2017.11.120] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 11/20/2017] [Accepted: 11/22/2017] [Indexed: 11/22/2022]
|
8
|
JANÁK D, HÁLA P, MLČEK M, POPKOVÁ M, LACKO S, KUDLIČKA J, KITTNAR O. Detection of Microembolic Signals in the Common Carotid Artery Using Doppler Sonography in the Porcine Model of Acute Heart Failure Treated by Veno-Arterial Extracorporeal Membrane Oxygenation. Physiol Res 2017; 66:S529-S536. [DOI: 10.33549/physiolres.933806] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a method used for the treatment most severe cases of decompensated heart failure. The purpose of this study was to evaluate the risk of the formation of microembolisms during VA-ECMO-based therapy. Heart failure was induced with simultaneous detection of microembolisms and the measurement of blood flow rate in the common carotid artery (CCA) without VA-ECMO (0 l/min) and at the VA-ECMO blood flow rate of 1, 2, 3 and 4 l/min. If embolisms for VA-ECMO 0 l/min and the individual regimes for VA-ECMO 1, 2, 3, 4 l/min are compared, a higher VA-ECMO flow rate is accompanied by a higher number of microembolisms. The final microembolism value at 16 min was for the VA-ECMO flow rate of 0 l/min 0.0 (0, 1), VA-ECMO l/min 7.5 (4, 19), VA-ECMO 2 l/min 12.5 (4, 26), VA-ECMO 3 l/min, 21.0 (18, 57) and VA-ECMO 4 l/min, 27.5 (21, 64). Such a comparison is statistically significant if VA-ECMO 0 vs. 4 l/min p<0.0001, 0 vs. 3 l/min p<0.01 and 1 vs. 4 l/min p<0.01 are compared. The results confirm that high VA-ECMO flow rates pose a risk with regards to the formation of a significantly higher number of microemboli in the blood circulation and that an increase in blood flow rates in the CCA corresponds to changes in the VA-ECMO flow rates.
Collapse
Affiliation(s)
- D. JANÁK
- Department of Physiology, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | | | | | | | | | | | | |
Collapse
|
9
|
Yildirim E, Kalkan K, Ipek E, Demirelli S, Ermiş E. Successful resolution of left ventricular thrombus with apixaban treatment. INTERNATIONAL JOURNAL OF THE CARDIOVASCULAR ACADEMY 2016. [DOI: 10.1016/j.ijcac.2015.12.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
10
|
Successful resolution of a left ventricular thrombus with apixaban treatment following acute myocardial infarction. Heart Vessels 2014; 31:118-23. [DOI: 10.1007/s00380-014-0562-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 07/18/2014] [Indexed: 12/22/2022]
|
11
|
Abstract
Cardiac disease, in particular coronary artery disease, is the leading cause of mortality in developed nations. Strokes can complicate cardiac disease - either as result of left ventricular dysfunction and associated thrombus formation or of therapy for the cardiac disease. Antiplatelet drugs and anticoagulants routinely used to treat cardiac disease increase the risk for hemorrhagic stroke.
Collapse
Affiliation(s)
- Moneera N Haque
- Division of Cardiology, Department of Medicine, Loyola University Chicago, Stritch School of Medicine, Chicago, IL, USA
| | - Robert S Dieter
- Division of Cardiology, Department of Medicine, Loyola University Chicago, Stritch School of Medicine, Chicago, IL, USA.
| |
Collapse
|
12
|
Slark J, Bentley P, Sharma P. Silent brain infarction in the presence of systemic vascular disease. JRSM Cardiovasc Dis 2012; 1:10.1258_cvd.2012.012002. [PMID: 24175060 PMCID: PMC3738320 DOI: 10.1258/cvd.2012.012002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objective To determine the prevalence of asymptomatic brain ischaemic in the presence of vascular disease in other arterial territories. Design Studies up to January 2011 were identified through comprehensive search strategies. Arcsine transformation for meta-analysis was used to calculate the standardized mean difference (SMD) and 95% confidence intervals (CI). Setting A systematic review and meta-analysis were performed. Participants For each study, the proportion of patients positive for SBI in the presence of other systemic vascular disease was extracted and analyzed. Main outcome measures Using a random-effects model, a pooled effect estimate interpreted as a percentage prevalence of disease was calculated. Results SBI in the presence of acute ischaemic stroke was found in 23% (SMD 0.99; P < 0.001; 95% CI 0.88–1.10); a 35% prevalence was found in patients with coronary artery disease (SMD 1.26; P < 0.001; 95% CI 0.95–1.58); and a 14% prevalence in patients with peripheral artery disease (SMD 0.48; P < 0.002; 95% CI 0.42–0.54), although the data-set in the latter is smaller. Conclusions Patients with systemic vascular disease are at an increased risk of silent brain infarction.
Collapse
Affiliation(s)
- Julia Slark
- Imperial College Cerebrovascular Research Unit (ICCRU), Department of Clinical Neurology, Imperial College London , London W6 8RF , UK
| | | | | |
Collapse
|
13
|
Font MÀ, Krupinski J, Arboix A. Antithrombotic medication for cardioembolic stroke prevention. Stroke Res Treat 2011; 2011:607852. [PMID: 21822469 PMCID: PMC3148601 DOI: 10.4061/2011/607852] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 03/02/2011] [Accepted: 03/27/2011] [Indexed: 01/28/2023] Open
Abstract
Embolism of cardiac origin accounts for about 20% of ischemic strokes. Nonvalvular atrial fibrillation is the most frequent cause of cardioembolic stroke. Approximately 1% of population is affected by atrial fibrillation, and its prevalence is growing with ageing in the modern world. Strokes due to cardioembolism are in general severe and prone to early recurrence and have a higher long-term risk of recurrence and mortality. Despite its enormous preventive potential, continuous oral anticoagulation is prescribed for less than half of patients with atrial fibrillation who have risk factors for cardioembolism and no contraindications for anticoagulation. Available evidence does not support routine immediate anticoagulation of acute cardioembolic stroke. Anticoagulation therapy's associated risk of hemorrhage and monitoring requirements have encouraged the investigation of alternative therapies for individuals with atrial fibrillation. New anticoagulants being tested for prevention of stroke are low-molecular-weight heparins (LMWH), unfractionated heparin, factor Xa inhibitors, or direct thrombin inhibitors like dabigatran etexilate and rivaroxaban. The later exhibit stable pharmacokinetics obviating the need for coagulation monitoring or dose titration, and they lack clinically significant food or drug interaction. Moreover, they offer another potential that includes fixed dosing, oral administration, and rapid onset of action. There are several concerns regarding potential harm, including an increased risk for hepatotoxicity, clinically significant bleeding, and acute coronary events. Therefore, additional trials and postmarketing surveillance will be needed.
Collapse
Affiliation(s)
- M. Àngels Font
- Institut d'Investigacions Biomèdiques de Bellvitge (IDIBELL), Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, 08907 Barcelona, Spain
- Department of Neurology, Hospital Sant Joan de Déu de Manresa (Fundació Althaia), Catalonia, 08243 Manresa, Spain
| | - Jerzy Krupinski
- Department of Neurology, Cerebrovascular Diseases Unit, Hospital Universitari Mútua de Terrassa, Catalonia, 08227 Terrassa, Spain
| | - Adrià Arboix
- Cerebrovascular Division, Department of Neurology, Hospital Universitari Sagrat Cor, University of Barcelona, C/Viladomat 288, Catalonia, 08029 Barcelona, Spain
| |
Collapse
|
14
|
Telman G, Mesica O, Kouperberg E, Cohen O, Bolotin G, Agmon Y. Microemboli monitoring by trans-cranial doppler in patient with acute cardioemboliogenic stroke due to atrial myxoma. Neurol Int 2010; 2:e5. [PMID: 21577341 PMCID: PMC3093209 DOI: 10.4081/ni.2010.e5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 12/09/2009] [Accepted: 01/20/2010] [Indexed: 11/22/2022] Open
Abstract
This is the first reported attempt to examine the emboliogenic potential of cardiac myxoma in patients with acute stroke through the monitoring of microembolic signals (MES) by transcranial doppler. A 43-year old woman was brought to the emergency department because of acute onset of generalized tonic-clonic seizures and left hemiplegia. A CT scan of the brain demonstrated a large acute infraction in the territory of the right middle cerebral artery (MCA) and another smaller one in the territory of the posterior cerebral artery on the same side. Trans-cranial doppler (TCD) microemboli monitoring did not reveal MES. Transesophagial echocardiography (TEE) identified a 5 cm left atrial mass, which was highly suspected to be an atrial myxoma attached to the interatrial septum and prolapsed through the mitral valve. After the TEE results were obtained, another TCD monitoring was performed. Again, there were no MES found in either of the MCAs.Our findings showed the absence of MES on two consecutive TCD examinations, suggesting a spontaneous occurrence, rather than the permanent presence, of embolization, even in the most acute phase of stroke. Thus, the tendency of myxomas to spontaneously produce multiple emboli emphasizes the need for the surgical excision of myxomas.
Collapse
|
15
|
Sauvé MJ, Lewis WR, Blankenbiller M, Rickabaugh B, Pressler SJ. Cognitive Impairments in Chronic Heart Failure: A Case Controlled Study. J Card Fail 2009; 15:1-10. [DOI: 10.1016/j.cardfail.2008.08.007] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Revised: 08/08/2008] [Accepted: 08/12/2008] [Indexed: 11/17/2022]
|
16
|
Ng HS, Nygaard H, Hasenkam JM, Johansen P. Gaseous emboli detection based on a dual-wavelet transform analysis. Proc Inst Mech Eng H 2007; 221:687-98. [DOI: 10.1243/09544119jeim295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Emboli monitoring is nowadays based on the assessment of microembolic signals by Doppler ultrasound. However, the present systems have problems in detecting multiple emboli. A more dedicated algorithm for post-processing of the recorded Doppler signals was proposed. Based on the hypothesis that single and multiple gaseous emboli can be quantified by combining discrete and continuous wavelet transformation, the aim of this study was to detect gaseous emboli and to validate our method visually. A flow rig was used where gaseous emboli were generated. Doppler signals and visual validation data of gaseous emboli were acquired simultaneously. Microembolic signals were extracted and analysed using wavelet transformation. Results were validated against a visual reference. At various degrees of bubble generation, the system had 100 per cent detection during a low frequency of bubble generation but an estimation error of 7.4 per cent during a high frequency of bubble generation. The estimation error varied between - 7.4 and +3 per cent. The system had a higher rate of success in detecting large gaseous emboli in small numbers than small gaseous emboli in large numbers. Single and double emboli were successfully detected and separated, whereas gaseous emboli clouds could be detected but not quantified. Being able to separate simultaneous gaseous emboli may offer new means of increasing detectability for embolism monitoring.
Collapse
Affiliation(s)
- H S Ng
- Department of Biomedical Engineering, Engineering College of Aarhus, Aarhus, Denmark
- Department of Cardiothoracic and Vascular Surgery and Institute of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - H Nygaard
- Department of Biomedical Engineering, Engineering College of Aarhus, Aarhus, Denmark
- Department of Cardiothoracic and Vascular Surgery and Institute of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - J M Hasenkam
- Department of Cardiothoracic and Vascular Surgery and Institute of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - P Johansen
- Department of Biomedical Engineering, Engineering College of Aarhus, Aarhus, Denmark
- Department of Cardiothoracic and Vascular Surgery and Institute of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark
| |
Collapse
|
17
|
Azarpazhooh MR, Chambers BR. Clinical application of transcranial Doppler monitoring for embolic signals. J Clin Neurosci 2006; 13:799-810. [PMID: 16908159 DOI: 10.1016/j.jocn.2005.12.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Accepted: 12/20/2005] [Indexed: 12/12/2022]
Abstract
A major advantage of transcranial ultrasound is its suitability for continuous monitoring. Microembolic signals (MES) are brief, high-intensity transients that occur when particulate microemboli or gaseous microbubbles pass through the ultrasound beam. These MES have been detected in several clinical scenarios, but rarely in age-matched controls. The detection of MES provides important pathophysiological information in a variety of disorders, but their clinical importance and possible therapeutic implications are still under debate. The present article summarizes the significance of MES in different clinical settings and outlines some of the problems to be resolved so that transcranial ultrasound can be applied in clinical practice.
Collapse
Affiliation(s)
- M R Azarpazhooh
- National Stroke Research Institute, University of Melbourne, Austin Health, Heidelberg Heights, Victoria, Australia
| | | |
Collapse
|
18
|
Palanchon P, Bouakaz A, Klein J, de Jong N. Multifrequency Transducer for Microemboli Classification and Sizing. IEEE Trans Biomed Eng 2005; 52:2087-92. [PMID: 16366231 DOI: 10.1109/tbme.2005.857641] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The classification of circulating microemboli as gaseous or particulate matter is essential to establish the relevance of the detected embolic signals. Until now, Doppler techniques have failed to determine unambiguously the nature of circulating microemboli. Recently, a new approach based on the analysis of radio frequency (RF) signal and using the nonlinear characteristics of gaseous bubbles to classify emboli was investigated. The main limitation of these studies was the requirement of two separate transducers for transmission and reception. This paper presents a multi-frequency transducer with two independent transmitting elements and a separate receiving part with a wide frequency band. The transmitting elements are positioned in a concentric design and cover a frequency band between 100 and 600 kHz. The receiving part consists of a polyvinylidene fluoride layer. The new transducer has been tested in vitro using gaseous emboli. It could correctly classify and size air emboli with diameters ranging from 10 microm to 105 microm.
Collapse
Affiliation(s)
- Peggy Palanchon
- Department of Cardiology, Thoraxcentre, Erasmus Medical Center Rotterdam, 3000 DR Rotterdam, The Netherlands.
| | | | | | | |
Collapse
|
19
|
Hayes PD, Box H, Tull S, Bell PRF, Goodall A, Naylor AR. Patients' thromboembolic potential after carotid endarterectomy is related to the platelets' sensitivity to adenosine diphosphate. J Vasc Surg 2004; 38:1226-31. [PMID: 14681619 DOI: 10.1016/j.jvs.2003.05.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
UNLABELLED Background and purpose Postoperative microemboli in patients undergoing carotid endarterectomy are a significant risk factor for stroke. These emboli can be detected by intraoperative transcranial Doppler monitoring. They are not linked to technical error and are variable between patients. As it is known that platelets play a key role in arterial thrombosis, it was hypothesized that a patient's risk of postoperative carotid thrombosis was linked to the individual's platelet response to physiologic agonists. METHODS Blood samples from 120 patients undergoing carotid endarterectomy were analyzed before surgery. Platelet aggregation was measured in response to adenosine diphosphate (ADP) (0.5 to 4 micromol/L), collagen (10 to 50 mg/mL), and arachidonic acid (3 or 6 micromol/L), and fibrinogen binding to GPIIb-IIIa was measured by whole blood flow cytometry in response to ADP (0.1 to 10 micromol/L) and thrombin (0.02 to 0.16 micro/mL). Patients underwent intraoperative transcranial Doppler monitoring for 3 hours after surgery, and platelet functional data of those who had >25 emboli in this period (n = 22) were compared with the data of those with <25 emboli (n = 88). RESULTS The platelet response to ADP was significantly higher in the patients with >25 emboli, as measured both by aggregometry (P =.0012) and by flow cytometry (P <.0001). Platelet aggregation with collagen was also significantly higher in this group (P =.0018), but the response to thrombin was not statistically different in the two groups. In addition, there was no difference in the response to arachidonic acid between the groups. CONCLUSION The platelet response to ADP may be linked to clinical outcome, and thus, specific ADP receptor inhibitors may be appropriate for this group of patients.
Collapse
Affiliation(s)
- Paul D Hayes
- Departmernt of Surgery, University of Leicester, Leicester Royal Infirmary, Clinical Sciences Building, Leicester, LE3 1LJ, UK.
| | | | | | | | | | | |
Collapse
|
20
|
Babikian VL, Wijman CA. Brain Embolism Monitoring with Transcranial Doppler Ultrasound. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2003; 5:221-232. [PMID: 12777200 DOI: 10.1007/s11936-003-0006-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Embolism is considered to be the main mechanism leading to brain infarction today; with the introduction of sophisticated neuroimaging tools, its impact is increasingly appreciated. Transcranial Doppler ultrasound allows noninvasive monitoring of in vivo embolism. Acute stroke, internal carotid artery stenosis, several cardiac conditions, internal carotid endarterectomy, and coronary artery bypass graft surgery have been extensively monitored. These investigations and other clinical and neuroimaging studies have expanded the understanding of brain embolism; they suggest it may be appropriate to think of it as a process that occurs in the context of other hemodynamic factors. Differences have been identified among several conditions regarding the temporal profile of embolism and the characteristics of embolic particles. This article presents a brief review of brain embolism monitoring with transcranial Doppler ultrasound.
Collapse
Affiliation(s)
- Viken L. Babikian
- Stroke Service, Department of Neurology, Boston University School of Medicine, 715 Albany Street, D-315, Boston, MA 02118, USA.
| | | |
Collapse
|
21
|
Gokterin O, Uzener N, Ata N, Kudaiberdieva G, Gucuyener D, Ozdemir G, Timuralp B. Does short-term anticoagulation with heparin increase risk for microemboli patients undergoing transesophageal guided electrical cardioversion for atrial fibrillation? A transcranial Doppler ultrasonography study. Int J Cardiol 2003; 88:107-12. [PMID: 12659996 DOI: 10.1016/s0167-5273(02)00373-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Electrical cardioversion (ECV) in patients with atrial fibrillation (AF) is known to be associated with an increased peri-procedural risk for thromboembolic events. ECV of AF for at least 3 weeks of effective oral anticoagulation was recently determined to be disassociated with occurrence of cerebral circulating microemboli (ME). Nonetheless, whether ECV in patients undergoing short-term anticoagulation with heparin is concomitant with cerebral ME still remains obscure. The objective of this study was to determine whether or not short-term anticoagulation with heparin helps avoid microemboli before and immediately after cardioversion of AF in patients undergoing transesophageal echocardiography (TEE)-guided ECV. METHOD A total of 34 patients (21 women, aged 61+/-12 years) who underwent TEE-guided ECV were enrolled into the study. All the patients underwent treatment with heparin for 3 days for anticoagulation before ECV. Transcranial Doppler ultrasonography (TCD) of the right middle cerebral artery and left middle cerebral artery was simultaneously performed through the temporal skull with a two-channel 2-MHz probe in all patients lasting for 30 min before ECV and 30 min immediately after successive ECV. RESULTS No ME were detected in 34 patients during the 30-min period during AF before ECV. Similarly, after ECV no ME were observed during 30-min monitoring in 27 patients who were converted to sinus rhythm. None of the patients presented with clinical signs or symptoms suggestive of manifest cerebral embolism either before or after ECV. CONCLUSION TCD monitoring did not disclose any evidence of microemboli in short-term anticoagulated patients with heparin before and immediately after TEE-guided ECV.
Collapse
|
22
|
Nadareishvili ZG, Beletsky V, Black SE, Fremes SE, Freedman M, Kurzman D, Leach L, Norris JW. Is cerebral microembolism in mechanical prosthetic heart valves clinically relevant? J Neuroimaging 2002; 12:310-5. [PMID: 12380477 DOI: 10.1111/j.1552-6569.2002.tb00138.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE High-intensity transient signals (HITS) are frequently detected by transcranial Doppler (TCD) ultrasound in patients with mechanical prosthetic heart valves (PHVs), but published data about their clinical relevance are controversial. This study was undertaken to determine the clinical relevance of HITS in patients with mechanical PHVs. METHODS The authors prospectively studied patients with mechanical PHVs using TCD monitoring for microemboli detection with and without O2 inhalation. The cognitive testing of patients included the Mini-Mental State Examination, the Dementia Rating Scale, and MicroCog. RESULTS The authors studied 36 patients (20 women, aged 58 +/- 13 years). HITS were detected in 72% of patients, with a nonsignificant increase of HITS rate in the aortic valve group (P = .07). There was no significant difference in HITS rate between asymptomatic and symptomatic patients. In a multiple linear regression model, HITS rate was predicted only by younger age (P = .024). No correlation was found between HITS rate and the cognitive performance of patients. There was a significant decrease in HITS rate after 100% O2 inhalation compared to baseline levels (32.8 +/- 40.2 vs 6.1 +/- 11.3, P = .011). Subgroup analysis in asymptomatic patients confirmed this finding (P = .017), but in symptomatic patients, decreased HITS rate was not statistically significant (P = .18). CONCLUSION Only age was a significant predictor of HITS in patients with mechanical PHVs. The lack of association between HITS, clinical symptoms, and cognitive functioning suggests that most of these signals represent harmless epiphenomena, and only HITS detected after O2 inhalation have any clinical relevance.
Collapse
Affiliation(s)
- Zurab G Nadareishvili
- Stroke Research Unit, Division of Neurology, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, Canada.
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
Cardiogenic embolism is increasingly appreciated as an important and preventable cause of stroke. Several potential sources of embolism have been identified with the advent of transoesophageal echocardiography. Their role as independent risk factors for stroke and management implications based on recent evidence, along with characterization of schemes for antithrombotic management of patients with atrial fibrillation are reviewed.
Collapse
Affiliation(s)
- Santiago Palacio
- Department of Medicine, Neurology, University of Texas Health Science Center, San Antonio, Texas 78229-3900, USA.
| | | |
Collapse
|
24
|
Hayes PD, Allroggen H, Steel S, Thompson MM, London NJ, Bell PR, Naylor AR. Randomized trial of vein versus Dacron patching during carotid endarterectomy: influence of patch type on postoperative embolization. J Vasc Surg 2001; 33:994-1000. [PMID: 11331840 DOI: 10.1067/mva.2001.115005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE A recent overview indicated that although routine patching is safer than routine primary closure after carotid endarterectomy (CEA), there is no systematic evidence that patch type influences outcome. However, most surgeons still believe that prosthetic patches are probably more thrombogenic than vein patches. This study tested the hypothesis that there was no difference in thrombogenicity between the different patch types. METHODS A total of 274 patients undergoing 276 CEAs were randomized to either Dacron-patch closure (n = 137) or vein-patch closure (n = 139). All patients with an accessible cranial window were monitored for 3 hours postoperatively with transcranial Doppler scanning (TCD). The number of emboli and rate of embolization were quantified with the requirement for selective dextran therapy to control high rates of postoperative embolization. All patients were assessed postoperatively and again at 30 days by a neurologist, and all patients underwent a duplex examination at 30 days. RESULTS The 30-day death/any stroke rate was 2.2% for patients in the Dacron-patch group and 3.6% for patients in the vein-patch group (P =.72). Patients in the Dacron-patch group had a higher incidence of postoperative emboli (median, 5; interquartile range, 0-10.5) than patients in the vein-patch group (median, 3; interquartile range, 1-17; P =.028). However, the incidence of detecting more than 50 emboli was virtually identical, and patch type had no effect on the incidence of high-rate, sustained embolization that required dextran therapy (5.3% for Dacron, 3.7% for vein). No patient had a carotid thrombosis at 30 days. CONCLUSION Sustained, high-rate embolization, previously shown to be highly predictive of progression to carotid thrombosis, appears to be patient dependent, rather than related to patch type.
Collapse
Affiliation(s)
- P D Hayes
- Department of Vascular Surgery and Neurology, The Leicester Royal Infirmary, UK
| | | | | | | | | | | | | |
Collapse
|