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Galasso M, Cavallotti C, Giannattasio C, Pedrotti P. Naphazoline abuse: a rare case of myocardial infarction with nonobstructive coronary arteries. J Cardiovasc Med (Hagerstown) 2024; 25:391-393. [PMID: 38555584 DOI: 10.2459/jcm.0000000000001604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
Nasal vasoconstrictors are some of the most widely used over-the-counter drugs, considered by many consumers as relatively safe with few significant adverse effects. At recommended dosage, the drug produces local vasoconstriction in nasal mucous membranes. However, the use of such drugs has been linked to cardiovascular adverse effects, including hypertension, arrhythmias, prolongation of the QT interval, and angina pectoris.
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The various cardiovascular adverse effects may occur with both oral and nasal administration and after a single dose or prolonged treatment, without dose-effect and independently of vascular status and age.
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Although the effects of ephedrine and pseudoephedrine have been widely studied, the effects of naphazoline are less well known. We describe the case of a previously healthy man who experienced a MINOCA (myocardial infarction with nonobstructive coronary arteries) after abuse of recommended dose of naphazoline. To our knowledge, this is the first time that a strict temporal relation between the occurrence of MINOCA and topical naphazoline abuse is being described.
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Affiliation(s)
- Michele Galasso
- School of Medicine and Surgery, University of Milano-Bicocca
| | | | - Cristina Giannattasio
- School of Medicine and Surgery, University of Milano-Bicocca
- Cardiologia I
- Cardiologia IV, De Gasperis, Cardio Center, Niguarda Hospital, Milan, Italy
| | - Patrizia Pedrotti
- Cardiologia IV, De Gasperis, Cardio Center, Niguarda Hospital, Milan, Italy
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Hokimoto S, Kaikita K, Yasuda S, Tsujita K, Ishihara M, Matoba T, Matsuzawa Y, Mitsutake Y, Mitani Y, Murohara T, Noda T, Node K, Noguchi T, Suzuki H, Takahashi J, Tanabe Y, Tanaka A, Tanaka N, Teragawa H, Yasu T, Yoshimura M, Asaumi Y, Godo S, Ikenaga H, Imanaka T, Ishibashi K, Ishii M, Ishihara T, Matsuura Y, Miura H, Nakano Y, Ogawa T, Shiroto T, Soejima H, Takagi R, Tanaka A, Tanaka A, Taruya A, Tsuda E, Wakabayashi K, Yokoi K, Minamino T, Nakagawa Y, Sueda S, Shimokawa H, Ogawa H. JCS/CVIT/JCC 2023 guideline focused update on diagnosis and treatment of vasospastic angina (coronary spastic angina) and coronary microvascular dysfunction. J Cardiol 2023; 82:293-341. [PMID: 37597878 DOI: 10.1016/j.jjcc.2023.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/21/2023]
Affiliation(s)
| | - Koichi Kaikita
- Division of Cardiovascular Medicine and Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Japan
| | - Satoshi Yasuda
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Japan
| | - Kenichi Tsujita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Japan
| | - Masaharu Ishihara
- Department of Cardiovascular and Renal Medicine, School of Medicine, Hyogo Medical University, Japan
| | - Tetsuya Matoba
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Japan
| | - Yasushi Matsuzawa
- Division of Cardiology, Yokohama City University Medical Center, Japan
| | - Yoshiaki Mitsutake
- Division of Cardiovascular Medicine, Kurume University School of Medicine, Japan
| | - Yoshihide Mitani
- Department of Pediatrics, Mie University Graduate School of Medicine, Japan
| | - Toyoaki Murohara
- Department of Cardiology, Nagoya University Graduate School of Medicine, Japan
| | - Takashi Noda
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Japan
| | - Koichi Node
- Department of Cardiovascular Medicine, Saga University, Japan
| | - Teruo Noguchi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Japan
| | - Hiroshi Suzuki
- Division of Cardiology, Department of Internal Medicine, Showa University Fujigaoka Hospital, Japan
| | - Jun Takahashi
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Japan
| | - Yasuhiko Tanabe
- Department of Cardiology, Niigata Prefectural Shibata Hospital, Japan
| | - Atsushi Tanaka
- Department of Cardiovascular Medicine, Wakayama Medical University, Japan
| | - Nobuhiro Tanaka
- Division of Cardiology, Tokyo Medical University Hachioji Medical Center, Japan
| | - Hiroki Teragawa
- Department of Cardiovascular Medicine, JR Hiroshima Hospital, Japan
| | - Takanori Yasu
- Department of Cardiovascular Medicine and Nephrology, Dokkyo Medical University Nikko Medical Center, Japan
| | - Michihiro Yoshimura
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Japan
| | - Yasuhide Asaumi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Japan
| | - Shigeo Godo
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Japan
| | - Hiroki Ikenaga
- Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences, Japan
| | - Takahiro Imanaka
- Department of Cardiovascular and Renal Medicine, School of Medicine, Hyogo Medical University, Japan
| | - Kohei Ishibashi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Japan
| | - Masanobu Ishii
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Japan
| | | | - Yunosuke Matsuura
- Division of Cardiovascular Medicine and Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Japan
| | - Hiroyuki Miura
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Japan
| | - Yasuhiro Nakano
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Japan
| | - Takayuki Ogawa
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Japan
| | - Takashi Shiroto
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Japan
| | | | - Ryu Takagi
- Department of Cardiovascular Medicine, JR Hiroshima Hospital, Japan
| | - Akihito Tanaka
- Department of Cardiology, Nagoya University Graduate School of Medicine, Japan
| | - Atsushi Tanaka
- Department of Cardiovascular Medicine, Saga University, Japan
| | - Akira Taruya
- Department of Cardiovascular Medicine, Wakayama Medical University, Japan
| | - Etsuko Tsuda
- Department of Pediatric Cardiology, National Cerebral and Cardiovascular Center, Japan
| | - Kohei Wakabayashi
- Division of Cardiology, Cardiovascular Center, Showa University Koto-Toyosu Hospital, Japan
| | - Kensuke Yokoi
- Department of Cardiovascular Medicine, Saga University, Japan
| | - Toru Minamino
- Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine, Japan
| | - Yoshihisa Nakagawa
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
| | - Shozo Sueda
- Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Japan
| | - Hiroaki Shimokawa
- Graduate School, International University of Health and Welfare, Japan
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Samaras A, Moysidis DV, Papazoglou AS, Rampidis G, Kampaktsis PN, Kouskouras K, Efthymiadis G, Ziakas A, Fragakis N, Vassilikos V, Giannakoulas G. Diagnostic Puzzles and Cause-Targeted Treatment Strategies in Myocardial Infarction with Non-Obstructive Coronary Arteries: An Updated Review. J Clin Med 2023; 12:6198. [PMID: 37834842 PMCID: PMC10573806 DOI: 10.3390/jcm12196198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/14/2023] [Accepted: 09/19/2023] [Indexed: 10/15/2023] Open
Abstract
Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myocardial infarction (MI), occurring in about 8-10% of spontaneous MI cases referred for coronary angiography. Unlike MI with obstructive coronary artery disease, MINOCA's pathogenesis is more intricate and heterogeneous, involving mechanisms such as coronary thromboembolism, coronary vasospasm, microvascular dysfunction, dissection, or plaque rupture. Diagnosing MINOCA presents challenges and includes invasive and non-invasive strategies aiming to differentiate it from alternative diagnoses and confirm the criteria of elevated cardiac biomarkers, non-obstructive coronary arteries, and the absence of alternate explanations for the acute presentation. Tailored management strategies for MINOCA hinge on identifying the underlying cause of the infarction, necessitating systematic diagnostic approaches. Furthermore, determining the optimal post-MINOCA medication regimen remains uncertain. This review aims to comprehensively address the current state of knowledge, encompassing diagnostic and therapeutic approaches, in the context of MINOCA while also highlighting the evolving landscape and future directions for advancing our understanding and management of this intricate myocardial infarction subtype.
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Affiliation(s)
- Athanasios Samaras
- First Department of Cardiology, AHEPA University Hospital, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece; (A.S.); (D.V.M.); (A.S.P.); (G.R.); (G.E.); (A.Z.)
- Second Cardiology Department, Hippokration General Hospital of Thessaloniki, 546 42 Thessaloniki, Greece;
| | - Dimitrios V. Moysidis
- First Department of Cardiology, AHEPA University Hospital, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece; (A.S.); (D.V.M.); (A.S.P.); (G.R.); (G.E.); (A.Z.)
- Third Cardiology Department, Hippokration General Hospital of Thessaloniki, 546 42 Thessaloniki, Greece;
| | - Andreas S. Papazoglou
- First Department of Cardiology, AHEPA University Hospital, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece; (A.S.); (D.V.M.); (A.S.P.); (G.R.); (G.E.); (A.Z.)
| | - Georgios Rampidis
- First Department of Cardiology, AHEPA University Hospital, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece; (A.S.); (D.V.M.); (A.S.P.); (G.R.); (G.E.); (A.Z.)
| | - Polydoros N. Kampaktsis
- Department of Medicine, Columbia University Irving Medical Center/NewYork-Presbyterian Hospital, New York, NY 10032, USA;
| | - Konstantinos Kouskouras
- Department of Radiology, AHEPA University General Hospital of Thessaloniki, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece;
| | - Georgios Efthymiadis
- First Department of Cardiology, AHEPA University Hospital, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece; (A.S.); (D.V.M.); (A.S.P.); (G.R.); (G.E.); (A.Z.)
| | - Antonios Ziakas
- First Department of Cardiology, AHEPA University Hospital, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece; (A.S.); (D.V.M.); (A.S.P.); (G.R.); (G.E.); (A.Z.)
| | - Nikolaos Fragakis
- Second Cardiology Department, Hippokration General Hospital of Thessaloniki, 546 42 Thessaloniki, Greece;
| | - Vasileios Vassilikos
- Third Cardiology Department, Hippokration General Hospital of Thessaloniki, 546 42 Thessaloniki, Greece;
| | - George Giannakoulas
- First Department of Cardiology, AHEPA University Hospital, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece; (A.S.); (D.V.M.); (A.S.P.); (G.R.); (G.E.); (A.Z.)
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Foà A, Canton L, Bodega F, Bergamaschi L, Paolisso P, De Vita A, Villano A, Mattioli AV, Tritto I, Morrone D, Lanza GA, Pizzi C. Myocardial infarction with nonobstructive coronary arteries: from pathophysiology to therapeutic strategies. J Cardiovasc Med (Hagerstown) 2023; 24:e134-e146. [PMID: 37186564 DOI: 10.2459/jcm.0000000000001439] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a heterogeneous group of clinical entities characterized by clinical evidence of acute myocardial infarction (AMI) with normal or near-normal coronary arteries on coronary angiography (stenosis < 50%) and without an over the alternative diagnosis for the acute presentation. Its prevalence ranges from 6% to 11% among all patients with AMI, with a predominance of young, nonwhite females with fewer traditional risks than those with an obstructive coronary artery disease (MI-CAD). MINOCA can be due to either epicardial causes such as rupture or fissuring of unstable nonobstructive atherosclerotic plaque, coronary artery spasm, spontaneous coronary dissection and cardioembolism in-situ or microvascular causes. Besides, also type-2 AMI due to supply-demand mismatch and Takotsubo syndrome must be considered as a possible MINOCA cause. Because of the complex etiology and a limited amount of evidence, there is still some confusion around the management and treatment of these patients. Therefore, the key focus of this condition is to identify the underlying individual mechanisms to achieve patient-specific treatments. Clinical history, electrocardiogram, echocardiography, and coronary angiography represent the first-level diagnostic investigations, but coronary imaging with intravascular ultrasound and optical coherent tomography, coronary physiology testing, and cardiac magnetic resonance imaging offer additional information to understand the underlying cause of MINOCA. Although the prognosis is slightly better compared with MI-CAD patients, MINOCA is not always benign and depends on the etiopathology. This review analyzes all possible pathophysiological mechanisms that could lead to MINOCA and provides the most specific and appropriate therapeutic approach in each scenario.
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Affiliation(s)
- Alberto Foà
- Cardiology Unit, Cardiac Thoracic and Vascular Department, IRCCS Azienda Ospedaliero-Universitaria di Bologna
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), IRCCS Policlinico St. Orsola-Malpighi, Alma Mater Studiorum University of Bologna, Bologna
| | - Lisa Canton
- Cardiology Unit, Cardiac Thoracic and Vascular Department, IRCCS Azienda Ospedaliero-Universitaria di Bologna
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), IRCCS Policlinico St. Orsola-Malpighi, Alma Mater Studiorum University of Bologna, Bologna
| | - Francesca Bodega
- Cardiology Unit, Cardiac Thoracic and Vascular Department, IRCCS Azienda Ospedaliero-Universitaria di Bologna
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), IRCCS Policlinico St. Orsola-Malpighi, Alma Mater Studiorum University of Bologna, Bologna
| | - Luca Bergamaschi
- Cardiology Unit, Cardiac Thoracic and Vascular Department, IRCCS Azienda Ospedaliero-Universitaria di Bologna
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), IRCCS Policlinico St. Orsola-Malpighi, Alma Mater Studiorum University of Bologna, Bologna
| | - Pasquale Paolisso
- Department of Advanced Biomedical Sciences, University of Naples, Federico II, Naples, Italy
- Cardiovascular Center Aalst, OLV Hospital, Aalst, Belgium
| | - Antonio De Vita
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome
| | - Angelo Villano
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome
| | | | - Isabella Tritto
- Università di Perugia, Dipartimento di Medicina, Sezione di Cardiologia e Fisiopatologia Cardiovascolare, Perugia
| | - Doralisa Morrone
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine-Cardiology Division, University Hospital of Pisa, Italy
| | - Gaetano Antonio Lanza
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome
| | - Carmine Pizzi
- Cardiology Unit, Cardiac Thoracic and Vascular Department, IRCCS Azienda Ospedaliero-Universitaria di Bologna
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), IRCCS Policlinico St. Orsola-Malpighi, Alma Mater Studiorum University of Bologna, Bologna
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5
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Yamashita A, Asada Y. Underlying mechanisms of thrombus formation/growth in atherothrombosis and deep vein thrombosis. Pathol Int 2023; 73:65-80. [PMID: 36598039 DOI: 10.1111/pin.13305] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 12/03/2022] [Accepted: 12/17/2022] [Indexed: 01/05/2023]
Abstract
Thrombosis remains a leading cause of death worldwide despite technological advances in prevention, diagnosis, and treatment. The traditional view of arterial thrombus formation is that it is a platelet-dependent process, whereas that of venous thrombus formation is a coagulation-dependent process. Current pathological and basic studies on atherothrombosis and venous thrombosis have revealed the diverse participation of platelet and coagulation activation mechanisms in both thrombus initiation and growth processes during clinical thrombotic events. Atherosclerotic plaque cell-derived tissue factor contributes to fibrin formation and platelet aggregation. The degree of plaque disruption and a blood flow alteration promote atherothrombotic occlusion. While blood stasis/turbulent flow due to luminal stenosis itself initiates venous thrombus formation. The coagulation factor XI-driven propagation phase of blood coagulation plays a major role in venous thrombus growth, but a minor role in hemostasis. These lines of evidence indicate that atherothrombosis onset is affected by the thrombogenic potential of atherosclerotic plaques, the plaque disruption size, and an alteration in blood flow. Upon onset of venous thrombosis, enhancement of the propagation phase of blood coagulation under blood stasis and a hypercoagulable state contribute to large thrombus formation.
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Affiliation(s)
- Atsushi Yamashita
- Pathophysiology Section, Department of Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yujiro Asada
- Pathophysiology Section, Department of Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.,Department of Pathology, Miyazaki Medical Association Hospital, Miyazaki, Japan
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Ortega-Paz L, Galli M, Capodanno D, Brugaletta S, Angiolillo DJ. The Role of Antiplatelet Therapy in Patients With MINOCA. Front Cardiovasc Med 2022; 8:821297. [PMID: 35237672 PMCID: PMC8882905 DOI: 10.3389/fcvm.2021.821297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 12/17/2021] [Indexed: 11/13/2022] Open
Abstract
Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a heterogeneous group of clinical entities characterized by the common clinical evidence of myocardial infarction (MI) with non-obstructive coronary arteries on coronary angiography and without an overt cause for the MI. Platelets play a cornerstone role in the pathophysiology of MI with obstructive coronary arteries. Accordingly, antiplatelet therapy is recommended for treating patients with MI and obstructive coronary disease. However, the role of platelets in the pathophysiology of MINOCA patients is not fully defined, questioning the role of antiplatelet therapy in this setting. In this review, we will assess the role of antiplatelet therapy in MINOCA with a focus on the pathophysiology, therapeutic targets, current evidence, and future directions according to its different etiologies.
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Affiliation(s)
- Luis Ortega-Paz
- Division of Cardiology, University of Florida College of Medicine, Jacksonville, FL, United States
- Cardiovascular Institute, Hospital Clinic, August Pi i Sunyer Biomedical Research Institute, Barcelona, Spain
| | - Mattia Galli
- Division of Cardiology, University of Florida College of Medicine, Jacksonville, FL, United States
- Cardiovascular Medicine, Fondazione Policlinico Universitario A Gemelli Scientific Institute for Research, Hospitalization and Healthcare, Rome, Italy
| | - Davide Capodanno
- Division of Cardiology, Azienda Ospedaliero Universitaria Policlinico “G. Rodolico-San Marco” University of Catania, Catania, Italy
| | - Salvatore Brugaletta
- Cardiovascular Institute, Hospital Clinic, August Pi i Sunyer Biomedical Research Institute, Barcelona, Spain
| | - Dominick J. Angiolillo
- Division of Cardiology, University of Florida College of Medicine, Jacksonville, FL, United States
- *Correspondence: Dominick J. Angiolillo ; orcid.org/0000-0001-8451-2131
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Intracoronary Thrombogenicity in Patients with Vasospastic Angina: An Observation Using Coronary Angioscopy. Diagnostics (Basel) 2021; 11:diagnostics11091632. [PMID: 34573973 PMCID: PMC8472720 DOI: 10.3390/diagnostics11091632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/26/2021] [Accepted: 09/03/2021] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Despite significant interest in intracoronary thrombi in patients with vasospastic angina (VSA), the phenomenon remains unclarified. Therefore, we investigated a possible relationship using coronary angioscopy (CAS) in VSA patients. METHODS Sixty patients with VSA, for whom we could assess the spastic segment using CAS, were retrospectively studied. An intracoronary thrombus on CAS was a white thrombus and an erosion-like red thrombus. We verified the clinical characteristics and lesional characteristics as they determined the risk of intracoronary thrombus formation. RESULTS There were 18 (30%) patients with intracoronary thrombi. More of the patients with intracoronary thrombi were male, current smokers and had severe concomitant symptoms; however, no statistically significant difference was observed upon logistic regression analysis. There were 18 (26%) coronary arteries with intracoronary thrombi out of 70 coronary arteries recognised in the spastic segments. Furthermore, atherosclerotic changes and segmental spasms were significant factors responsible for such lesions. CONCLUSION Intracoronary thrombi occurred in 30% of VSA patients and much attention should be paid to the intracoronary thrombogenicity of VSA patients.
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Asada Y, Yamashita A, Sato Y, Hatakeyama K. Pathophysiology of atherothrombosis: Mechanisms of thrombus formation on disrupted atherosclerotic plaques. Pathol Int 2020; 70:309-322. [PMID: 32166823 PMCID: PMC7317428 DOI: 10.1111/pin.12921] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 02/26/2020] [Indexed: 12/14/2022]
Abstract
Atherothrombosis is a leading cause of cardiovascular mortality and morbidity worldwide. The underlying mechanisms of atherothrombosis comprise plaque disruption and subsequent thrombus formation. Arterial thrombi are thought to mainly comprise aggregated platelets as a result of high blood velocity. However, thrombi that develop on disrupted plaques comprise not only aggregated platelets, but also large amounts of fibrin, because plaques contain large amount of tissue factor that activate the coagulation cascade. Since not all thrombi grow large enough to occlude the vascular lumen, the propagation of thrombi is also critical in the onset of adverse vascular events. Various factors such as vascular wall thrombogenicity, local hemorheology, systemic thrombogenicity and fibrinolytic activity modulate thrombus formation and propagation. Although the activation mechanisms of platelets and the coagulation cascade have been intensively investigated, the underlying mechanisms of occlusive thrombus formation on disrupted plaques remain obscure. Pathological findings derived from humans and animal models of human atherothrombosis have uncovered pathophysiological processes during thrombus formation and propagation after plaque disruption, and novel factors have been identified that modulate the activation of platelets and the coagulation cascade. These findings have also provided insights into the development of novel drugs for atherothrombosis.
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Affiliation(s)
- Yujiro Asada
- Pathophysiology Section, Department of Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Atsushi Yamashita
- Pathophysiology Section, Department of Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yuichiro Sato
- Department of Diagnostic Pathology, University of Miyazaki Hospital, University of Miyazaki, Miyazaki, Japan
| | - Kinta Hatakeyama
- Department of Diagnostic Pathology, Nara Medical University, Nara, Japan
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Ito S, Hasuo T. Intravascular Images of Coronary Stenosis with Multiple Channels in a Patient with Antiphospholipid Syndrome: The Optical Coherence Tomography Findings. Intern Med 2017; 56:1351-1356. [PMID: 28566597 PMCID: PMC5498198 DOI: 10.2169/internalmedicine.56.7804] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Intravascular images of coronary stenosis by antiphospholipid syndrome (APS) would be beneficial to understand the mechanism of this disease. A 59-year-old woman with APS/systemic lupus erythematosis (SLE) underwent emergent coronary angiography which revealed stenosis with micro channels in the proximal left anterior descending artery. According to optical coherence tomography (OCT), the central lumen was surrounded by a thick septum with a homogenous and high intensity. Multiple small channels existed near the vessel wall with diffuse intimal hyperplasia. White thrombi were floating distal to the stenosis. Intravascular images obtained by optical coherence tomography (OCT) revealed the microstructure of complex coronary stenosis, which had ambiguous findings on angiography and intravascular ultrasound (IVUS) in an acute coronary syndrome (ACS) patient with APS/SLE.
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Affiliation(s)
- Shigenori Ito
- Division of Cardiology, Nagoya City East Medical Center, Japan
| | - Takahiro Hasuo
- Division of Cardiology, Nagoya City East Medical Center, Japan
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Shibutani H, Akita Y, Matsui Y, Yoshinaga M, Karakawa M. The potential hazard of drug-eluting stent-induced coronary vasospasm causing subacute stent thrombosis: a case report. BMC Cardiovasc Disord 2016; 16:236. [PMID: 27887648 PMCID: PMC5124276 DOI: 10.1186/s12872-016-0410-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/14/2016] [Indexed: 11/22/2022] Open
Abstract
Background Drug-eluting stent (DES) -induced coronary vasospasm is a well known phenomenon after stent implantation; however, the extent of this risk is still unknown. We report a case in which DES-induced severe coronary vasospasm was clinically suspected as a cause of subacute stent thrombosis (ST). Case presentation A 67-year-old man came to our hospital due to chest pain with mild exercise. He was diagnosed with effort angina by coronary angiography and underwent DES implantation in the mid-left ascending artery (LAD) after the administration of dual anti-platelet therapy. The procedure was uneventful, but his symptoms changed from effort angina to rest angina after stenting. Five days after the procedure, subacute ST occurred, requiring aspiration thrombectomy and balloon angioplasty. Thereafter, he continued to report early morning chest discomfort. We performed a spasm provocation test to evaluate the coronary vasomotor response; it revealed severe stent-edge spasm in the left main trunk to the LAD, except for the stented lesion, and total occlusion of the left circumflex artery. Conclusions To our knowledge, the present case is the first report describing in-stent thrombosis secondary to stent-edge spasm. This case describes the potential hazard of DES-induced coronary vasospasm. Although there are several overlapping risk factors for ST development, we consider that stent-edge spasm also plays an important role in ST development. Therefore, we should monitor new-onset rest angina after stent implantation and carefully assess DES-induced coronary vasospasm.
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Affiliation(s)
- Hiroki Shibutani
- Division of Cardiology, Osaka Saiseikai Izuo Hospital, 3-4-5 Kitayama, Taisho-ku, Osaka, 551-0032, Japan.
| | - Yuzo Akita
- Division of Cardiology, Osaka Saiseikai Izuo Hospital, 3-4-5 Kitayama, Taisho-ku, Osaka, 551-0032, Japan
| | - Yumie Matsui
- Division of Cardiology, Osaka Saiseikai Izuo Hospital, 3-4-5 Kitayama, Taisho-ku, Osaka, 551-0032, Japan
| | - Masahiro Yoshinaga
- Division of Cardiology, Osaka Saiseikai Izuo Hospital, 3-4-5 Kitayama, Taisho-ku, Osaka, 551-0032, Japan
| | - Masahiro Karakawa
- Division of Cardiology, Osaka Saiseikai Izuo Hospital, 3-4-5 Kitayama, Taisho-ku, Osaka, 551-0032, Japan
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Mizuno Y, Hokimoto S, Harada E, Kinoshita K, Nakagawa K, Yoshimura M, Ogawa H, Yasue H. Variant Aldehyde Dehydrogenase 2 (ALDH2*2) Is a Risk Factor for Coronary Spasm and ST-Segment Elevation Myocardial Infarction. J Am Heart Assoc 2016; 5:e003247. [PMID: 27153870 PMCID: PMC4889196 DOI: 10.1161/jaha.116.003247] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 04/03/2016] [Indexed: 11/25/2022]
Abstract
BACKGROUND Mitochondrial aldehyde dehydrogenase 2 (ALDH2) plays a key role in removing toxic aldehydes. Deficient variant ALDH2*2 genotype is prevalent in up to 40% of the East Asians and reported to be associated with acute myocardial infarction (AMI). To elucidate the mechanisms underlying the association of ALDH2*2 with AMI, we compared the clinical features of AMI patients with ALDH2*2 to those with wild-type ALDH2*1/*1. METHODS AND RESULTS The study subjects consisted of 202 Japanese patients with acute ST-segment elevation myocardial infarction (STEMI) (156 men and 46 women; mean age, 67.3±12.0) who underwent primary percutaneous coronary intervention (PCI). In 85 patients, provocation test for coronary spasm was also done 6 month post-PCI. ALDH2 genotyping was performed by direct application of the TaqMan polymerase chain system. Of the 202 patients, 103 (51.0%) were carriers of ALDH2*2 and 99 (49.0%) those of ALDH2*1/*1. There were no differences in clinical features between ALDH2*2 and ALDH2*1/*1 carrier groups except higher frequencies of coronary spasm and alcohol flush syndrome (AFS) (88.6% vs 56.1%; P=0.001 and 94.3% vs 17.6%; P<0.001), less-frequent alcohol habit (14.6% vs 51.5%; P<0.001), and higher peak plasma creatine phophokinase levels (2224 vs 1617 mg/dL; P=0.002) in the ALDH2*2 than the ALDH2*1/*1 carrier group. CONCLUSIONS ALDH2*2 is prevalent (51.0%) among Japanese STEMI patients, and those with ALDH2*2 had higher frequencies of coronary spasm and AFS and more-severe myocardial injury compared to those with ALDH2*1/*1.
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Affiliation(s)
- Yuji Mizuno
- Division of Cardiovascular Medicine, Kumamoto Kinoh Hospital, Kumamoto Aging Research Institute, Kumamoto, Japan
| | - Seiji Hokimoto
- Department of Cardiovascular Medicine, Faculty of Life Science, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Eisaku Harada
- Division of Cardiovascular Medicine, Kumamoto Kinoh Hospital, Kumamoto Aging Research Institute, Kumamoto, Japan
| | - Kenji Kinoshita
- School of Pharmaceutical Sciences, Mukogawa Women's University, Koshien Nishinomiya, Japan
| | - Kazuko Nakagawa
- Division of Pharmacology and Therapeutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
| | - Michihiro Yoshimura
- Division of Cardiology, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Hisao Ogawa
- Department of Cardiovascular Medicine, Faculty of Life Science, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Hirofumi Yasue
- Division of Cardiovascular Medicine, Kumamoto Kinoh Hospital, Kumamoto Aging Research Institute, Kumamoto, Japan
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12
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Ito S, Ohmori H. Subclinical very late thrombus formation inside and outside the everolimus-eluting stent implanted 3 years prior in a patient with provoked coronary spasms. Cardiovasc Interv Ther 2015; 32:72-76. [PMID: 26660342 DOI: 10.1007/s12928-015-0372-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 11/24/2015] [Indexed: 11/27/2022]
Abstract
A 63-year-old man with non-ST-elevation acute myocardial infarction had undergone PROMUS Element stent implantation for stenosis with thrombus in the left main trunk and the proximal left anterior descending artery. A 6-month follow-up angiography revealed no restenosis or stent thrombosis, but severe provoked spasms in three vessels, for which medications were administered. Three years later, the patient experienced new-onset rest angina one morning. Optical coherence tomography revealed subclinical very late stent thromboses inside and outside the stent. The patients experienced a severe spasm. Platelet function was adequately reduced, and the cytochrome P450 2C19 genotype indicated an extensive metabolizer phenotype. The spasm may have caused the thromboses.
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Affiliation(s)
- Shigenori Ito
- Division of Cardiology, Nagoya City East Medical Center, Nagoya, Japan. .,Higashiyama Clinic, The Junshukai Medical Foundation, Nagoya, Japan.
| | - Hiroyuki Ohmori
- Division of Cardiology, Nagoya City East Medical Center, Nagoya, Japan
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13
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Abstract
Platelets play a central role in the pathogenesis of atherosclerosis and thrombosis. Platelet adhesion and aggregate formation are critical events that occur in unstable coronary syndromes. Platelet activation precedes the formation of homotypic and heterotypic aggregates. In the last 10 years, researchers have described the presence of activated platelets in the systemic circulation in various cardiovascular disease states, particularly acute coronary syndromes. This review describes the evidence for platelet activation in acute myocardial ischemic syndromes, describes the pathophysiology responsible for its occurrence, and discusses how platelet activation and reactivity may affect the use of concomitant drug therapies and patient prognosis.
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Affiliation(s)
- Paul A Gurbel
- John Hopkins University School of Medicine, Sinai Center for Thrombosis Research, Hoffberger Building, Suite 56, 2401 W. Belvedere Avenue, Baltimore, MD 21215, USA.
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14
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Abstract
Abnormal coronary vasoconstriction, or coronary spasm, can be the result of several factors, including local and neuroendocrine aberrations. It can manifest clinically as a coronary syndrome and plays an important role in the genesis of myocardial ischemia. Over the past half century, coronary angiography allowed the in vivo demonstration of spasm in patients who fit the initial clinical description of the condition as reported by Prinzmetal et al. Several clinical, basic, and more recently, genetic studies have provided insight into the pathogenesis, manifestations, and therapy of this condition. It is not uncommonly encountered in patients with coronary syndromes and absence of clearly pathologic lesions on angiography. Provocation tests utilizing pharmacologic and nonpharmacologic stimuli combined with imaging (echocardiography or coronary angiography) can help make the correct diagnosis. The use of calcium channel blockers and long-acting nitrates is currently considered standard of care and the overall prognosis appears to be good. The recent discovery of genetic abnormalities predisposing to abnormal spasm of the coronaries has stimulated interest in the development of targeted therapies for the management of this condition.
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Sumi T, Yamashita A, Matsuda S, Goto S, Nishihira K, Furukoji E, Sugimura H, Kawahara H, Imamura T, Kitamura K, Tamura S, Asada Y. Disturbed blood flow induces erosive injury to smooth muscle cell-rich neointima and promotes thrombus formation in rabbit femoral arteries. J Thromb Haemost 2010; 8:1394-402. [PMID: 20230423 DOI: 10.1111/j.1538-7836.2010.03843.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Plaque erosion is a cause of atherothrombosis that preferentially occurs on smooth muscle cell (SMC)- and proteoglycan-rich rather than lipid-rich plaques. However, its underlying mechanisms remain unknown. OBJECTIVE To determine whether disturbed blood flow induces erosive injury and thrombus formation on SMC-rich neointima. METHODS Three weeks after balloon injury, SMC-rich neointima with increased tissue factor (TF) activity developed in rabbit femoral arteries that were narrowed with a vascular occluder to disturb blood flow after stenosis. Neointimal injury and thrombus formation were assessed at 15, 30, and 180 min after the vascular narrowing. RESULTS Endothelial detachment, platelet adhesion and neointimal cell apoptosis became evident at the post-stenotic regions of all femoral arteries (n = 5) within 15 min of narrowing. Mural thrombi composed of platelet and fibrin developed after 30 min, and then occlusive thrombi were generated in three out of five vessels after 180 min. The identical vascular narrowing of normal femoral arteries also induced endothelial detachment with small platelet thrombi at post-stenotic regions, but fibrin and occlusive thrombi did not develop. Computational simulation analysis indicated that oscillatory shear stress contributes to the development of erosive damage to the neointima. CONCLUSIONS These results suggest that disturbed post-stenotic blood flow can induce erosive injury in SMC-rich plaques and promote thrombus formation that results in vascular events.
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Affiliation(s)
- T Sumi
- Department of Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
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16
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Li X, Iwai T, Nakamura H, Inoue Y, Chen Y, Umeda M, Suzuki H. An ultrastructural study of Porphyromonas gingivalis-induced platelet aggregation. Thromb Res 2008; 122:810-9. [PMID: 18448150 DOI: 10.1016/j.thromres.2008.03.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Revised: 12/23/2007] [Accepted: 03/04/2008] [Indexed: 10/22/2022]
Abstract
One of the major pathogens of periodontitis, Porphyromonas gingivalis (P. gingivalis), has the ability to aggregate human platelets. To investigate the interaction between P. gingivalis and human platelets in platelet rich plasma (PRP), platelet aggregation was measured by an aggregometer based on laser light scattering (LS) methods, and an ultrastructural study was performed using electron microscopy. A sharp and rapid increase of small-sized platelet aggregates was observed immediately after the addition of P. gingivalis to PRP, followed by the formation of medium- and large-sized aggregates in 2-3 min. In contrast, when Staphylococcus aureus (S. aureus) was used in the control experiment, only a slight increase in small-sized aggregates was detected. By electron microscopy, discoid-shaped platelets were observed prior to adding P. gingivalis. By 5 min after the addition of the bacteria, enormous platelet aggregates were observable. Most of the P. gingivalis were present between the adherent platelets, while some were internalized in platelet engulfment vacuoles. In contrast, when washed platelets were incubated with the bacteria under a non-stirring condition to prevent platelet aggregation, and stained with ruthenium red (RR) as an electron dense tracer of the cell surface including the open canalicular system (OCS), both RR-positive and -negative vacuoles containing P. gingivalis were identified in the activated platelets. Thus, this observation suggests that P. gingivalis residing in the RR-negative vacuoles is incorporated into the platelet cytoplasm by phagocytosis.
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Affiliation(s)
- Xiangfeng Li
- Department of Surgery, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
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17
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Vernick WJ. How long to postpone an operation after a myocardial infarction? J Clin Anesth 2006; 18:325-7. [PMID: 16905075 DOI: 10.1016/j.jclinane.2006.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2006] [Accepted: 05/03/2006] [Indexed: 10/24/2022]
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Matsuno H, Tokuda H, Ishisaki A, Zhou Y, Kitajima Y, Kozawa O. P2Y12 receptors play a significant role in the development of platelet microaggregation in patients with diabetes. J Clin Endocrinol Metab 2005; 90:920-7. [PMID: 15483100 DOI: 10.1210/jc.2004-0137] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ninety-eight diabetic patients (type 2) were studied together with 24 healthy normotensive controls. Microaggregates (particle scale, <25 microm) of platelets were detected by a laser scattering system. Microaggregates in the control group showed a time-dependent reversible change; however, they existed continuously in 82 of 98 diabetic patients. When platelets of diabetics were stimulated by a shear stress alone without ADP, 74 also showed spontaneous and irreversible microaggregates even though they were not observed in all control subjects. In control subjects, microaggregates were inhibited by MRS2279 (a P2Y1 antagonist), but not AR-C69931MX (a P2Y12 antagonist). However, AR-C69931MX prevented irreversible microaggregates in diabetic patients. When either aspirin or ticlopidine was administered to diabetic patients with irreversible microaggregates, both drugs significantly decreased microaggregates induced by a low dose of ADP. Ticlopidine additionally reduced the microaggregates induced by shear stress alone. In conclusion, microaggregates of platelets via P2Y12 receptors could play a key role in the hypersensitivity of platelets in diabetic patients, and the measurement of microaggregation could be a useful marker to estimate of thrombogenesis. These findings present a possible new means for patients with diabetes to prevent ischemic events.
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Affiliation(s)
- Hiroyuki Matsuno
- Department of Clinical and Pathological Biochemistry, Doshisha-Women's College of Liberal Arts, Kyotanabe 610-0395, Japan.
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Hara K, Hirowatari Y, Yoshika M, Komiyama Y, Tsuka Y, Takahashi H. The ratio of plasma to whole-blood serotonin may be a novel marker of atherosclerotic cardiovascular disease. ACTA ACUST UNITED AC 2004; 144:31-7. [PMID: 15252405 DOI: 10.1016/j.lab.2004.03.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Because atherosclerotic vascular lesions stimulate platelets, the platelets release serotonin (5-hydroxytryptamine, aka 5-HT). We therefore measured 5-HT concentrations not only in platelet-poor plasma but also in whole blood as a means of assessing vascular lesions. The plasma concentration of 5-HT tended to increase with age, whereas that in whole blood decreases. Therefore the ratio of the plasma to the whole-blood concentration of 5-HT (P/WB) increases with age. This may be a result of the activation of platelets in older subjects with atherosclerotic vascular damage. Patients who underwent coronary angiography (CAG) were classified into 4 groups according to diagnosis: effort-induced angina pectoris (eAP), old myocardial infarction (OMI), vasospastic angina pectoris (VSAP), and unstable angina (uAP). The mean plasma 5-HT concentration was significantly (P <.01) greater in patients with eAP, uAP, OMI, and VSAP than in healthy controls, whereas the concentration in whole blood was lower in patients with eAP than in healthy controls. When the P/WB ratios were calculated, the mean levels in all disease groups were significantly higher than that in the healthy controls. These findings suggested that 5-HT is released into the plasma from the platelets and that the concentration in the platelets decreases in patients with atherosclerosis.
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Affiliation(s)
- Katsuko Hara
- Department of Clinical Sciences and Laboratory Medicine, Kansai Medical University, Moriguchi, Osaka, Japan
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Affiliation(s)
- Daniel B Brown
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, Missouri 63110, USA.
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21
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Takei M, Matsuno H, Okada K, Ueshima S, Matsuo O, Kozawa O. Lack of alpha 2-antiplasmin enhances ADP induced platelet micro-aggregation through the presence of excess active plasmin in mice. J Thromb Thrombolysis 2002; 14:205-11. [PMID: 12913400 DOI: 10.1023/a:1025096609558] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND The role of alpha2-antiplasmin (alpha2-AP) on platelet aggregation was investigated using mice deficient in alpha2-AP (alpha2-AP(-/-)) or using wild type mice (alpha2-AP(+/+)). METHODS Blood samples were taken from each mouse under anesthesia with ether and platelet rich plasma (PRP) was prepared. Platelet aggregation induced by various doses of ADP (0.3-30 microM) was detected using a laser-light scattering (LS) system. Aggregated forms were observed using a scanning electron microscopy (SEM). RESULTS Dose-dependent platelet aggregation was not different in both types of mice. However, platelet micro-aggregate formation in alpha2-AP(-/-) mice induced by low dose of ADP (1.0 microM) markedly increased compared to the situation in wild type mice. Aggregated form detected by SEM showed supported data from LS analysis. When washed platelets of alpha2-AP(+/+) mice were resuspended in plasma of alpha2-AP(-/-) mice, platelet micro-aggregation was also increased. On the contrary, when washed platelets of alpha2-AP(-/-) mice were suspended in plasma of alpha2-AP(+/+) mice, platelet micro-aggregation did not change. In separate experiments, tPA (1.0 microg/ml) was added to PRP before the stimulation of ADP. tPA had no effect on platelet aggregation in alpha2-AP(+/+) mice, however platelet micro-aggregation in alpha2-AP(-/-) mice was markedly increased by the treatment with tPA. Moreover, the amount of released ATP from stimulated platelets was increased in alpha2-AP(-/-) mice treated with tPA. CONCLUSION Lack of alpha2-AP increased platelet micro-aggregation, and plasmin plays an important role in the formation of platelet aggregation when alpha2-AP knockout mice are used. Consequently, the reduction of alpha2-AP could be a risk factor for the activation of platelets resulting in thrombus formation.
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Affiliation(s)
- Mariko Takei
- Department of Pharmacology, Gifu University School of Medicine, Tsukasa-machi 40, Gifu 500, Japan
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