Role of mean platelet volume in triagging acute coronary syndromes

Background: Acute coronary syndromes, characterized by the rupture of unstable plaque and the subsequent thrombotic process involving platelets, have been increasing in relative frequency. The central role of platelet activation has long been noticed in this pathophysiology; hence, many therapies have been directed against it. In this study, we have aimed to search prospectively the value of mean platelet volume (MPV), which is a simple and accurate measure of the functional status of platelets, in patients hospitalized with diagnosis of acute coronary syndromes (ACS). Materials and methods: A total of 216 consecutive patients (156 male, 60 female) hospitalized with the diagnosis of non-ST segment elevation (NSTE) ACS within the first 24 h of their chest pain were enrolled. One hundred and twenty patients, matched according to sex and age, with stable coronary heart disease (CHD) (85 male, 35 female) were enrolled as a control group. Patients were classified into two group: those with unstable angina (USAP, n = 105) and those with non-ST segment elevation myocardial infarction (NSTEMI, n = 111). Results: MPVs were 10.4 +/- 0.6 fL, 10 +/- 0.7 fL, 8.9 +/- 0.7 fL consecutively for NSTEMI, USAP and stable CHD with significant differences. Patients with ischemic attacks in the first day of hospitalization accompanied by >0.05 mV ST segment shift had significantly higher MPV compared to those without such attacks (P = 0.001). Multivariable logistic regression analysis yielded that MPV (P = 0.016), platelet count (P < 0.001), and the presence of >0.05 mV ST segment depression at admission (P = 0.002) were independent predictors of development of NSTEMI in patients presenting with NSTE ACS. Conclusion: In patients presenting with NSTE ACS, higher MPV, though there are overlaps among subgroups, indicates not only more risk of having NSTEMI but also ischemic complications.     

The relation between mean platelet volume and coronary collateral vessels in patients with acute coronary syndromes

ObjectiveElevated mean platelet volume (MPV) has been proposed as a risk factor for coronary artery disease (CAD) and is associated with poor clinical outcome in acute coronary syndrome (ACS). We aimed to evaluate the association of MPV with presence of coronary collateral vessel (CCV) in patients with ACS.MethodsA total of 417 patients with ACS were included in the study. All patients underwent coronary angiography on the first day after admission and patients with a greater than or equal to 80% obstruction in at least one epicardial coronary artery were included in the study. The CCVs are graded according to the Rentrop scoring system and a Rentrop grade 0 was accepted as no CCV development (Group 1), Rentrop Grade 1–2–3 were accepted as presence of CCV development (Group 2).ResultsThe median of MPV was 9.1 ± 1.4 fl. Mean age was 60 ± 12 year. Group 1 consisted of 233 (55.9%) patients and Group 2 consisted of 184 (44.1%) patients. Presence of CCV was significantly associated with high levels of MPV (p = 0.005). Presence of CCV was also associated with presence of diabetes and systolic blood pressure.ConclusionHigh MPV on admission was associated with presence of CCV in patients with ACS.     

平均血小板体积与急性冠脉综合征的研究进展

血小板在止血和血栓形成中发挥显著作用,活化的血小板通过释放参与炎症、动脉粥样硬化和血栓形成的介质,在心血管疾病的发病机制中发挥重要作用。平均血小板体积是血小板大小和活性的指标,大血小板的代谢和酶促活性更强,具有更强的促炎和血栓形成潜力,与急性冠脉综合征的发生发展密切相关。     

Diagnostic importance of admission platelet volume indices in patients with acute chest pain suggesting acute coronary syndrome

Objective

Acute coronary syndrome (ACS) is a challenging issue in cardiovascular medicine. Given platelet role in atherothrombosis, we sought to determine whether platelet indices can be used as diagnostic tests for patients who suffered from an acute chest discomfort.

Methods

We prospectively enrolled 862 patients with an acute chest pain and 184 healthy matched controls. They were divided into four groups: 184 controls, 249 of non-ACS, 421 of unstable angina (UA), and 192 of myocardial infarction (MI) cases. Blood samples were collected at admission to the emergency department for routine hematologic tests.

Results

The mean platelet volume (MPV), platelet distribution width (PDW), and platelet large cell ratio (P-LCR) were significantly greater in patients with MI compared with those of non-ACS or control subjects. Negative and significant correlations existed between MPV, PDW, and P-LCR values and platelet count (P < 0.001). Receiver operating characteristic (ROC) curves showed that the MPV, PDW, and P-LCR with cut-off values of 9.15 fL, 11.35 fL, and 20.25% and with area under the curves of 0.563, 0.557, and 0.560, respectively, detected MI patients among those who had chest discomfort. The sensitivities and specificities were found to be 72% and 40%, 73% and 37%, and 68% and 44% for MPV, PDW, and P-LCR, respectively.

Conclusion

An elevated admission MPV, PDW, and P-LCR may be of benefit to detect chest pain resulting in MI from that of non-cardiac one, and also for risk stratification of patients who suffered from an acute chest discomfort.     

Chest pain centers: diagnosis of acute coronary syndromes

Chest pain centers in the emergency department have generally been accepted as a safe, cost-effective, and rapid approach to the evaluation, triage, and management of patients with potential acute coronary syndromes. These centers were initially designed to enhance patient care by decreasing time to treatment for acute myocardial infarction (AMI) and rapidly identifying patients with unstable angina. They also included community outreach and educational objectives designed to reduce time from the onset of chest pain to ED presentation. In the past decade, health care financial constraints have created additional impetus to the development of chest pain centers. Cost reduction efforts have occurred to reduce hospitalizations, lengths of stay, and unnecessary treatments and procedures. Practitioners and administrators try to balance these goals with the imperative to provide high-quality patient care. Protocol-driven approaches have been developed for specific disease processes in emergency settings. The chest pain center concept is such an approach for patients with chest pain. Chest pain is the second most common ED presenting complaint and is a symptom related to the leading cause of death in the United States, coronary artery disease (CAD). One third of ED patients with chest pain will eventually have a diagnosis of acute coronary syndrome. Many patients with acute coronary syndromes have atypical presentations that are not diagnosed in the ED with the traditional diagnostic evaluation of a history, physical examination, and 12-lead ECG. If they are not admitted to the hospital for further evaluation, the diagnosis may be missed. The 2% to 5% of AMI patients who are inadvertently released home often have poor outcomes and result in a leading cause of malpractice suits in emergency medicine. More than one half of ED patients with chest pain have clinical findings after their initial evaluation consistent with acute coronary syndromes and are admitted to the hospital. Approximately one half of these patients, after evaluation in the hospital, are found not to have acute coronary syndromes. The cost for these negative inpatient cardiac evaluations has been estimated to be $6 billion in the United States each year. Today, chest pain centers serve as an integral component of many EDs. Their success and safety is the result of a focused, protocol-driven approach directed at the acute coronary syndrome continuum from unstable angina to transmural Q-wave myocardial infarction. New therapies for acute coronary syndromes make ED triage and risk stratification increasingly important. Although different chest pain center protocols have proved effective, all address the diagnosis and rapid treatment of acute myocardial necrosis, rest ischemia, and exercise-induced ischemia. Identifying patients with coronary artery disease in one of these stages in the spectrum of myocardial ischemia is the foundation for a successful chest pain center in the ED.     

非糖尿病、非肥胖、非ST段抬高急性冠状动脉综合征患者平均血小板体积与胰岛素抵抗的相关性分析

目的:观察无糖尿病、不肥胖的非ST段抬高急性冠状动脉综合征患者,平均血小板体积(mean platelet volume,MPV)与胰岛素抵抗的相关性和临床的意义。方法:连续入选236例非糖尿病、非肥胖、非ST段抬高急性冠状动脉综合征患者,测定外周血液学指标以及其他生化指标。根据稳态模型胰岛素抵抗指数(homeostasis model assessment insulin resistance index,HOMA-IR)分为胰岛素抵抗组90例和胰岛素敏感组146例。比较两组患者临床和血液学参数。结果:胰岛素抵抗患者男性(P=0.003)、高血压(P=0.004)、超质量(P0.001)比例高;服用β-受体阻滞剂(P=0.003)和硝酸脂类药物(P=0.001)比例高。胰岛素抵抗组患者TG、UA、高敏C-反应蛋白、空腹血糖、空腹胰岛素、C-肽、HOMA-IR、BMI、MPV、血小板分布宽度、大血小板比例、红细胞计数和血红蛋白含量,也较胰岛素敏感组患者明显增高(P0.05),HDL-C明显降低(P=0.03)。相关分析显示,MPV分别与HOMA-IR(r=0.35,P0.001)、空腹胰岛素(r=0.37,P0.001)、C-肽(r=0.27,P0.001)、血小板分布宽度(r=0.53,P0.001)、大血小板比例(r=0.74,P0.001)以及BMI(r=0.17,P=0.009)呈正相关,与血小板计数呈负相关(r=-0.46,P0.001)。结论:对于非糖尿病、非肥胖、非ST段抬高急性冠状动脉综合征患者,MPV在胰岛素抵抗组明显增加且与HOMA-IR呈显著正相关,胰岛素抵抗的非ST段抬高急性冠状动脉综合征患者血小板激活程度较高,应该采取更积极的抗血小板策略。     

Prognostic value of mean platelet volume in patients with non-ST-elevation acute coronary syndrome

The aim of this study is to determine mean platelet volume (MPV) in a population with non-ST-elevation acute coronary syndrome (nSTEACS) and explore its relation with prognosis. Patients (n = 329) with a diagnosis of nSTEACS at admission were recruited, with a determination of MPV in the first 12 hours at admission. We also collected blood from 87 healthy controls. A composite end point of cardiovascular death and new ACS was assessed at 6-month follow-up. Patients with nSTEACS showed larger platelets (MPV: 11.0 [10.3-11.8] vs 9.2 [8.6-10.0] fL; P < .001.). In Cox regression analysis, MPV at admission was a significant predictor of cardiovascular adverse events in univariate analysis, hazard ratio (HR) 1.4 95% confidence interval (CI) 1.1-1.8; P = .018; but after adjustment with clinical variables, MPV lost its statistical significance. In conclusion, patients with nSTEACS present with larger platelets than healthy controls, however this parameter did not show an independent prognostic significance at 6-month follow-up.     

Thrombopoietin and mean platelet volume in coronary artery disease

BACKGROUND: Large platelets are shown to be hemostatically more active. It has been suggested that mean platelet volume (MPV) is increased during acute myocardial infarction (AMI) and unstable angina pectoris (USAP). However, the underlying mechanism of the phenomenon remains unclear. HYPOTHESIS: In this study, platelets, MPV, and thrombopoietin (TP) levels were investigated in patients with coronary artery disease (CAD) and healthy controls. METHODS: Twenty patients with AMI and 20 patients with USAP were included in this study. Seventeen healthy adult subjects served as controls. Venous blood samples of the subjects were drawn within 12 h after admission. Thrombopoietin levels were measured by ELISA and platelet counts and MPV were assayed by autoanalyzer. RESULTS: Patients with AMI and USAP had higher platelet counts than those in the control group. Although the platelet counts were slightly higher in AMI than in USAP, this did not reach statistical significance. Mean platelet volume and levels of TP were found to be elevated in patients with AMI and USAP compared with control subjects (p < 0.001). Thrombopoietin levels were higher in AMI than USAP, but this was not statistically significant. There was a positive correlation between TP levels and MPV values (p < 0.05). CONCLUSION: Increased TP levels may increase both platelet counts and platelet size, resulting in hemostatically more active platelets, which may contribute to the development and progression of CAD.     

平均血小板体积及中性粒细胞/淋巴细胞比值与急性冠状动脉综合征相关性的研究进展

<正>急性冠状动脉综合征(acute coronary syndrome,ACS)是在动脉粥样硬化性疾病的基础上发生不稳定斑块破裂出血,血栓形成.继发冠状动脉痉挛或阻塞,导致心肌缺血或坏死的综合征。ACS主要包括不稳定型心绞痛(unstable angina pectoris,UAP)和急性心肌梗死(acute myocardial infarction,AMI)以及心脏性猝死(sudden cardiacdeath,SCD)。已有研究证实.血小板和炎症在动脉粥样硬化和血栓形成中起重要作用.是触发ACS的重要因素。平均血小板体积(mean platelet volume.MPV)作为血小板活化的生物学指标,与ACS     

Investigation and management of non-cardiac chest pain

Recurring substernal chest pain is an important clinical problem, causing anxiety for patients and their physicians because of the fear of possible cardiac disease. The differential diagnosis includes coronary artery disease, oesophageal disorders such as acid reflux disease and motility disturbances, musculoskeletal problems, psychological disorders including panic attacks, and a new 'fly in the ointment'--microvascular angina. History alone usually cannot distinguish cardiac from non-cardiac chest pain. After exclusion of significant coronary artery disease, attention must be turned to oesophageal disorders, which may be seen in as many as 50% of these patients. Oesophageal motility disorders, particularly the nutcracker oesophagus, are common, but the relationship between pain and abnormal contraction pressures is not well established. Provocative tests such as edrophonium (Tensilon) and balloon distension help to identify the oesophagus as the source of chest pain but do not direct therapy. Recent studies with ambulatory oesophageal monitoring suggest that gastro-oesophageal reflux may be a more common cause of chest pain than motility disorders. This is an important finding as acid reflux is a treatable problem, while therapies for motility disorders may only worsen reflux disease. The recent observation that oesophageal disorders are frequently associated and interact with psychological disorders such as anxiety, depression, somatization and panic attacks complicates the evaluation and understanding of chest pain. How these various abnormalities may be linked is an unresolved issue. Increased central nervous system stimulation and altered visceral and/or central pain sensitivity could be the common factors. It is hoped that further research into these areas will lead to new understandings of and possible solutions to the complex problem of non-cardiac chest pain.     

The pathophysiology of non-cardiac chest pain

Abstract:   Various underlying mechanisms have been described in patients with non-cardiac chest pain (NCCP). By far, gastroesophageal reflux disease (GERD) is the most common cause and thus requires initial attention when patients with NCCP are managed. Esophageal dysmotility can be demonstrated in 30% of the NCCP patients, but appears to play a very limited role in symptom generation. A significant number of patients with NCCP lack any evidence of GERD and have been consistently shown to have reduced perception thresholds for pain. Peripheral and/or central sensitization have been suggested to be responsible for visceral hypersensivity in NCCP patients. Further understanding of the underlying mechanisms for pain in patients with NCCP will likely improve our current therapeutic approach.     

平均血小板体积与冠心病的关系

血小板形态和功能的变化是心脑血管疾病发病机制中的重要独立危险因子之一。血小板在冠心病(CHD)的发生、发展过程中具有重要作用,但目前尚无明确反映血小板功能的指标,近年多项研究发现血小板参数中的平均血小板体积（MPV）是反映血小板活化的一个重要指标。检测MPV是评估血小板功能一种简单、快捷的方法,对预测CHD临床事件的发生具有一定的临床意义。     

Chest pain units. Organization and protocol for the diagnosis of acute coronary syndromes

The two main goals of chest pain units are the early, accurate diagnosis of acute coronary syndromes and the rapid, efficient recognition of low-risk patients who do not need hospital admission. Many clinical, practical, and economic reasons support the establishment of such units. Patients with chest pain account for a substantial proportion of emergency room turnover and their care is still far from optimal: 8% of patients sent home are later diagnosed of acute coronary syndrome and 60% of admissions for chest pain eventually prove to have been unnecessary.We present a systematic approach to create and manage a chest pain unit employing specialists headed by a cardiologist. The unit may be functional or located in a separate area of the emergency room. Initial triage is based on the clinical characteristics, the ECG and biomarkers of myocardial infarct. Risk stratification in the second phase selects patients to be admitted to the chest pain unit for 6-12 h. Finally, we propose treadmill testing before discharge to rule out the presence of acute myocardial ischemia or damage in patients with negative biomarkers and non-diagnostic serial ECGs.     

急性胸痛的鉴别

急性胸痛是患者到医院急诊部就医最常见的病因之一。对于急性胸痛,往往首先想到急性冠状动脉综合征(ACS),然而事实上仅15%～25%的急性胸痛患者被明确诊断为ACS[1],其中诊断的难点也就在于如何鉴别ACS与其