Increased mean platelet volume in patients with acute coronary syndromes

Evaluation of Platelet Indices in Patients with Splanchnic Vein Thrombosis

Splanchnic vein thrombosis (SVT) is a rare and lethal form of venous thrombosis. The role of platelet indices (PI's) is not well studied in SVT. The present study was aimed to assess if the PI's have a significant association with SVT. This was a prospective case control study from coagulation laboratory of Hematology department. A total 100 cases of SVT and 80 controls were screened for PI's (MPV, PCT & PDW) and platelet count (PC) along with routine thrombophilic risk factors. The SVT cases were divided into 3 subgroups, that comprised of EHPVO/ PVT (n = 69), BCS (n = 27), and MVT (n = 4). The mean PC and PCT were significantly lower in patients than the controls. The PDW was significantly higher in cases than in the controls and MPV was relatively higher in cases however did not show statistical significance. In addition, 16 patients were found to have deranged thrombophilic risk factors. Among these, 8 cases had inherited risk factors (2: FVL; 5: PC; 1: PS) and 8 cases had acquired risk factors (2: APL; and 5: multiple factors and one case had both FVL mutation and APL positivity). The PDW and PCT together with PC were found to significantly differ in SVT cases than in controls, particularly in idiopathic cases. It may be worthwhile to explore the utility of PI's as a potential risk factor in SVT.

Supplementary Information

The online version contains supplementary material available at (10.1007/s12288-021-01400-5).

Risk factors associated with progression of diabetic retinopathy in eyes treated with panretinal photocoagulation

Uncontrolled diabetes has been associated with progression of diabetic retinopathy (DR) in several studies. Therefore, we aimed to investigate systemic and ophthalmic factors related to worsening of DR even after completion of panretinal photocoagulation (PRP). We retrospectively reviewed DR patients who had completed PRP in at least one eye with a 3-year follow-up. A total of 243 eyes of 243 subjects (mean age 52.6 ± 11.6 years) were enrolled. Among them, 52 patients (21.4%) showed progression of DR after PRP (progression group), and the other 191 (78.6%) patients had stable DR (non-progression group). The progression group had higher proportion of proliferative DR (P = 0.019); lower baseline visual acuity (P < 0.001); and higher platelet count (P = 0.048), hemoglobin (P = 0.044), and hematocrit, (P = 0.042) than the non-progression group. In the multivariate logistic regression analysis for progression of DR, baseline visual acuity (HR: 0.053, P < 0.001) and platelet count (HR: 1.215, P = 0.031) were identified as risk factors for progression. Consequently, we propose that patients with low visual acuity or high platelet count are more likely to have progressive DR despite PRP and require careful observation. Also, the evaluation of hemorheological factors including platelet counts before PRP can be considered useful in predicting the prognosis of DR.

Systemic immune-inflammation index predicts the severity of coronary stenosis in patients with coronary heart disease

BACKGROUND

Coronary atherosclerosis is a systemic chronic inflammatory disease with variable occurrence and progression. Some laboratory parameters, such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and C-reactive protein (CRP) level, are used to evaluate the degree of inflammation and the severity of coronary artery disease (CAD). The neutrophil*platelet/lymphocyte is a novel systemic immune-inflammation index (SII), and its relationship with the development and severity of CAD is unclear.

OBJECTIVE

To investigate the association between the SII and the severity of CAD.

METHODS

Three-hundred and ninety-five patients who underwent coronary angiography were enrolled; among whom, 285 patients were included in the CAD group and 110 patients were included in the non-CAD group according to the WHO guidelines. Patients with CAD were further divided according to the Gensini score into the severe coronary stenosis group and the mild coronary stenosis group. The SII was calculated using the following formula: neutrophil*platelet/lymphocyte.

RESULTS

When the cutoff value of the SII was set at 439.44, the predictive power of CAD was the highest, with a sensitivity and specificity of 64.6 and 68.2%, respectively. When the cutoff value of the SII was set at 652.83, the predictive power of severe coronary stenosis was the highest, with a sensitivity and specificity of 71.0 and 86.0%, respectively. The area under the curve of the SII in predicting severe coronary stenosis was greater than that of the NLR, PLR and CRP level.

CONCLUSION

The SII is an independent risk factor for the occurrence and severity of CAD.

Influence of different methods and anticoagulants on platelet parameter measurement

Platelets are the smallest and perhaps the most versatile components of human blood. Besides their role in coagulation and the maintenance of vascular integrity, they are involved in many physiological processes, ranging from immune response and leukocyte recruitment to the production of antimicrobial peptides and immune-suppressive factors like TGF-β. These versatile abilities make platelets interesting for researchers from different disciplines. However, beside profound investigation into platelets’ physiological role, there is a need for correct, standardized and thus reproducible quantification of platelet parameters. Mean platelet volume (MPV) is a widespread prognostic marker for several conditions, such as, acute coronary syndrome, chronic kidney disease and liver cirrhosis. Platelet activation is regarded as a marker for inflammatory processes, for example in autoimmune diseases such as type-1 diabetes, systemic lupus erythematosus and rheumatoid arthritis. The monitoring of platelet function is relevant for patients receiving antiplatelet medication. Platelet parameter measurement is affected by the choice of in vitro anticoagulant, the measurement technology and the time delay after sampling. This review focuses on the pre-analytical variability that arises as a result of the use of different in vitro anticoagulants and analyzer technologies when determining platelet parameters, since, even approximately 180 years after the discovery of platelets, there is still no standardized procedure.

High red cell distribution width at the time of ST segment elevation myocardial infarction is better at predicting diastolic than systolic left ventricular dysfunction: A single-center prospective cohort study

Multiple studies have demonstrated the association of red cell distribution width (RDW) with the ultrasound parameters of both systolic and diastolic heart dysfunction. We aimed to further investigate the clinical associations of RDW in the setting of ST-elevation myocardial infarction (STEMI) and to comparatively evaluate its predictive properties regarding systolic and diastolic dysfunction.A total of 89 patients with STEMI were prospectively analyzed. RDW was obtained at the time of STEMI and compared to the parameters of systolic and diastolic dysfunction obtained by transthoracic heart ultrasound on the 5th through 7th day post-STEMI.The median RDW was 13.9%, and among other factors, RDW was significantly associated with older age (P < .001), arterial hypertension (P = .017), hyperlipoproteinemia 2, nonsmoking (P = .027), increased thrombolysis in myocardial infarction score (P = .004), and multivessel disease (P = .007). A higher RDW was observed in patients with parameters that indicated systolic and diastolic dysfunction (ejection fraction of the left ventricle < 50% [P = .009], early/late diastolic filling wave ratio [E/A] < 1 [P = .001], ratio of peak early transmitral velocity and early diastolic annular velocity [E/E'] >10 [P < .001], and combined E/A < 1 and E/E' > 10 [P < .001]). The best discriminatory properties were observed for combined E/A < 1 and E/E' > 10. RDW remained significantly associated with the aforementioned parameters in a series of multivariate regression models.Elevated RDW is significantly associated with the parameters of systolic and diastolic dysfunction even after adjusting for several confounding factors in the setting of STEMI and subsequent percutaneous coronary intervention. RDW seems to be better at discriminating patients with diastolic rather than systolic dysfunction.

Clinical use of Serial Mean Platelet Volume Measurement for Diagnosis of Non-ST Segment Elevation Myocardial Infarction in Patients Visiting Emergency Department with Acute Chest Pain

Objective

We aim to demonstrate diagnostic accuracy of serial MPV measuring and to assess its correlation with cardiac troponin I (cTnI) levels.

Design

Cross-sectional study.

Methods

Consecutive patients presenting to emergency department with new onset chest pain started in the last four hours without electrocardiographic ST segment and T wave changes, pathological q waves were included in study. Complete blood count and cTnI levels were studied on admission and six hours after presentation. Patients with cTnI levels higher than 0.06 ng/ml were diagnosed as non-ST elevation myocardial infarction (NSTEMI) and other patients were matched as the control group.

Results

NSTEMI group had significantly higher levels of MPV on admission and at the sixth hour. The increase in MPV was corraleted with elevation of cTnI levels. At six hours follow up, the increase in MPV levels predicted myocardial ischaemia (corrected r2=0.36; p=0.001) in linear regression analysis. The corresponding area under the receiver operating characteristic curve (ROC) for admission MPV, sixth hour MPV and increase in MPV levels in predicting myocardial ischaemia in patients with increased cTnI were 0.652, 0.727 and 0.896 respectively. If MPV threshold was selected as ≥0.10 fL during follow up, myocardial ischaemia was predicted with a sensitivity of 75% and specificity of 88%.

Conclusions

Elevation of MPV levels in patients with acute chest pain may be an indicator of myocardial ischaemia. Serial MPV measurement can be used to complement serial cTnI measurements to diagnose NSTEMI.

Combined measurement of factor XIII and D-dimer is helpful for differential diagnosis in patients with suspected pulmonary embolism

BACKGROUND

D-dimer has been used to rule out pulmonary embolism (PE). Based on previous reports of decreased concentrations of coagulation factor XIII (FXIII) in venous thromboembolism, and no change in FXIII concentration in patients with acute cardiovascular disease, we evaluated the benefit of simultaneously measuring D-dimer and FXIII concentrations for diagnosing PE.

METHODS

In this prospective single-center study, we enrolled 209 patients initially suspected of having PE, and measured their D-dimer and FXIII concentrations. Forty-one patients were diagnosed with PE and 168 with other final diagnoses, including acute coronary syndrome (ACS); aortic dissection (AD); spontaneous pneumothorax (SP); other respiratory, heart, digestive and nervous diseases; and uncertain diagnoses.

RESULTS

Patients with PE had significantly higher D-dimer and lower FXIII concentrations than did patients without PE. Combined D-dimer and FXIII measurements provided a higher positive predictive value (76.6%) for PE than single tests, especially in patients with Wells score >4.0 (89.3%). Specifically, patients with AD or ACS showed higher FXIII concentrations and mean platelet volumes than did patients with PE or SP, and patients with PE and AD had higher D-dimer concentrations than did other patients. At the thresholds of 69.0% for FXIII and 1.10 μg/mL for D-dimer, 123/151 patients (81.5%) with serious diseases (PE, AD, ACS and SP) were correctly distinguished.

CONCLUSIONS

Combined measurement of D-dimer and FXIII helps distinguish PE from serious diseases with similar symptoms and appears to relate to increased FXIII release from active platelets in cardiovascular disease.

Association between the rs342293 polymorphism and adverse cardiac events in patients undergoing percutaneous coronary intervention

The single nucleotide polymorphism (SNP) rs342293 has been shown to influence platelet number and mean platelet volume (MPV). We investigated the association between the rs342293 polymorphism and cardiovascular outcome in a prospective cohort study. The rs342293 polymorphism was analysed in 404 patients with coronary artery disease undergoing percutaneous coronary intervention. The rates of cardiac adverse events were recorded during two years of follow-up. The polymorphism was associated with MPV (median 10.1 fL, interquartile range [IQR]: 9.6 to 10.6 in patients with the CC-allele vs 10.4 fL, IQR: 9.9 to 11.1 in G>C SNP carriers; p<0.001), but not with platelet count. Survival analysis indicated that carriers of the rs342293 G variant had a substantially higher risk to develop cardiac adverse events compared with wild type carriers during two years of follow-up (33% vs 22%; adjusted hazard ratio = 1.63, 95% confidence interval = 1.06–2.52, p=0.027). The rs342293 SNP could explain 2.9% of the variability in MPV (p=0.01). In conclusion, patients undergoing coronary stenting who carry the G-variant of the rs342293 SNP which is associated with larger MPV are at higher risk for adverse cardiovascular outcome.

Significance of Platelet Volume Indices in STEMI Patients: A Case-Control Study

INTRODUCTION

Platelets have been well known contributors in the pathogenesis of cardiovascular disorders such as atherosclerosis and its complications such as acute Myocardial Infarction (MI).

AIM

To study the changes in platelet volume indices and platelet count in ST-Elevated Myocardial Infarction (STEMI) and assess their usefulness in predicting coronary events.

MATERIALS AND METHODS

A case-control observational study was carried out on 173 cases diagnosed with STEMI and 191 controls from January 2015 to December 2015, considering the inclusion and exclusion criteria. In total, 364 patients were included, 173 patients with STEMI, from those patients admitted to the intensive care unit and the emergency ward. In addition, 191 healthy non diabetic non hypertensive age-matched controls were enrolled.

RESULTS

The mean age of cases was 59.4±11.9 years and of controls were 55.25±8.5 years. Males (74.6%) had higher incidence of STEMI then females (25.4%). The Mean Platelet Volume (MPV) was significantly higher in patients with STEMI (10.2±2.8) as compared to controls (8.5±6.9). The Platelet Distribution Width (PDW) was also significantly higher in cases compared to controls (p<0.05). According to Pearson correlation analysis, the positive relationship determined between MPV and Gensini score was statistically significant (p < 0.001, r = 0.132).

CONCLUSION

High MPV and PDW seem to be an independent risk factor for STEMI and correlated with the severity of the STEMI. They can be used as a simple, reliable, and economical method for predicting an impending acute coronary event.

Platelet Count and Mean Platelet Volume at the Time of and After Acute Myocardial Infarction

Platelet count has been shown to be lower and mean platelet volume (MPV) to be higher in acute myocardial infarction (MI). However, it is not known whether these changes persist post-MI or if these measures are able to distinguish between acute thrombotic and non-thrombotic MI. Platelet count and MPV were measured in 80 subjects with acute MI (thrombotic and non-thrombotic) and stable coronary artery disease (CAD) at cardiac catheterization (acute phase) and at >3-month follow-up (quiescent phase). Subjects were stratified using stringent clinical, biochemical, histological, and angiographic criteria. Outcome measures were compared between groups by analysis of variance. Forty-seven subjects met criteria for acute MI with clearly defined thrombotic (n = 22) and non-thrombotic (n = 12) subsets. Fourteen subjects met criteria for stable CAD. No significant difference was observed in platelet count between subjects with acute MI and stable CAD at the acute or quiescent phase. MPV was higher in acute MI (9.18 ± 1.21) compared to stable CAD (8.13 ± 0.66; P = 0.003) at the acute phase but not at the quiescent phase (8.48 ± 0.58 vs 8.94 ± 1.42; P = 0.19). No difference in platelet count or MPV was detected between thrombotic and non-thrombotic subsets at acute or quiescent phases. The power to detect differences in these measures between thrombotic and non-thrombotic subsets was 58%. Higher MPV at the time of acute MI is not observed by 3 months post-MI (quiescent phase). Platelet count and MPV do not differ in subjects with thrombotic versus non-thrombotic MI. Further investigation is warranted to evaluate the utility of these measures in the diagnosis of acute MI.

Blood count parameters can predict the severity of coronary artery disease

BACKGROUND/AIMS

Because of the inflammatory nature of coronary artery disease (CAD), both platelets and white blood cells have been investigated for years. The aim of this study was to investigate the relationships between some prominently hematologic blood count parameters (mean platelet volume [MPV], neutrophil to lymphocyte ratio [NLR]) and the severity of CAD by using Gensini scores.

METHODS

A total of 194 patients, who had undergone coronary angiography, enrolled in this study. The control group consisted of 42 patients who had normal coronary arteries. Remaining CAD patients were divided into two groups according to their Gensini scores.

RESULTS

NLR and MPV were higher in the severe atherosclerosis group compared with the mild atherosclerosis group (p = 0.007, p = 0.005, respectively). The Gensini score showed significant correlations with NLR (r = 0.20, p = 0.011), MPV (r = 0.23, p = 0.004) and high density lipoprotein cholesterol (r = -0.161, p = 0.047). Using a cut-off level of 2.54, NLR predicted severe atherosclerosis with a sensitivity of 74% and specificity of 53% (area under curve [AUC], 0.627; 95% confidence interval [CI], 0.545 to 0.704; p = 0.004). MPV values above 10.4 predicted severe atherosclerosis with a sensitivity of 39% and specificity of 90% (AUC, 0.631; 95% CI, 0.549 to 0.708; p = 0.003). In the multiple logistic regression analysis, high levels of NLR (odds ratio [OR], 1.450; 95% CI, 1.080 to 1.945; p = 0.013) and MPV (OR, 1.622; 95% CI, 1.147 to 2.295; p = 0.006) were found to be independent predictors of severe atherosclerosis.

CONCLUSIONS

Our study suggests that both NLR and MPV are predictors of severe atherosclerosis and may be used for the prediction and identification of cardiac risks in CAD patients.

The acute effect of the antioxidant drug "U-74389G" on mean platelet volume levels during hypoxia reoxygenation injury in rats

Background

This experimental study examined the effect of the antioxidant drug "U-74389G", on a rat model and particularly in a hypoxia - reoxygenation protocol. The effects of that molecule were studied hematologically using blood mean platelets volume (MPV) levels.

Methods

40 rats of mean weight 231.875 g were used in the study. MPV levels were measured at 60 min of reoxygenation (groups A and C) and at 120 min of reoxygenation (groups B and D). The drug U-74389G was administered only in groups C and D.

Results

U-74389G administration kept significantly increased the predicted MPV levels by 12.77 ± 3.07% (p = 0.0001). Reoxygenation time non-significantly decreased the predicted MPV levels by 2.55 ± 3.71% (p = 0.4103). However, U-74389G administration and reoxygenation time together kept significantly increased the predicted MPV levels by 7.09 ± 1.91% (p = 0.0005).

Conclusions

U-74389G administration whether it interacted or not with reoxygenation time kept significantly increased the predicted MPV levels. This finding has great clinical interest in blood clotting and coagulation pathophysiology.

Diagnostic Value of Mean Platelet Volume Combined With Troponin I for Acute Coronary Syndrome

OBJECTIVE

To explore diagnostic performance of mean platelet volume (MPV) for acute myocardial infarction (AMI) of patients with acute coronary syndrome (ACS).

METHODS

We compared MPV and other indicators of 1,524 patients with ACS. Among them, 880 patients were diagnosed with AMI, 344 were diagnosed with unstable angina pectoris and 350 were the control group.

RESULTS

The level of MPV in ACS group was significantly higher than the control group (9.5 ± 1.34fL versus 7.9 ± 1.03fL, P < 0.001). Additionally, MPV of AMI group was higher than unstable angina pectoris (9.4 ± 1.30fL versus 9.2 ± 1.42fL, P < 0.001). Increased MPV could be identified as an early independent predictor of AMI (odds ratio = 1.957, 95% CI: 1.389-2.758, P < 0.001). The area under the receiver operating characteristic curves curve for MPV combined with troponin I (TnI) was 0.816, the sensitivity (68.81%) and the specificity (97.98%) at the best cut-off value were higher than using MPV or TnI alone respectively.

CONCLUSIONS

MPV has been shown as an independent risk factor for early onset of AMI and can be applied to assist AMI diagnosis of ACS patients. Additionally, measuring MPV in conjunction with TnI levels can improve the diagnostic performance of TnI with higher sensitivity and specificity.

Prognostic biomarkers in acute coronary syndrome

The acute coronary syndrome (ACS) is a leading cause of death around the globe. Beside a still high mortality rate, additional complications of ACS include arrhythmias, left ventricular mural thrombus, cardiac fibrosis, heart failure (HF), cardiogenic shock, mitral valve dysfunction, aneurysms, up to cardiac rupture. Despite many prognostic tools have been developed over the past decades, efforts are still ongoing to identify reliable and predictive biomarkers, which may help predict the prognosis of these patients and especially the risk of HF. Recent evidence suggests that the value of a discrete number of biomarkers of myocardial fibrosis, namely the soluble form of suppression of tumorigenicity 2 (sST2) and galectin-3 (GAL-3), may be predictive of HF and death in patients with ACS. Interestingly, the already promising predictive value of these biomarkers when measured alone was shown to be consistently magnified when combined with other and well-established cardiac biomarkers such natriuretic peptides and cardiac troponins. This article is hence aimed to review the current knowledge about cardiac biomarkers of fibrosis and adverse remodeling.

Magnesium Sulfate as an Alternative In Vitro Anticoagulant for the Measurement of Platelet Parameters?

OBJECTIVES

There are conflicting reports on the reliable measurement of platelet count and mean platelet volume (MPV) using EDTA or citrate. The anticoagulant properties of magnesium sulfate (MgSO4) are known from the literature. The aim of this study was to evaluate MgSO4 as an in vitro anticoagulant for platelet count, MPV, platelet distribution width, and platelet activation.

METHODS

Whole blood from volunteers was anticoagulated by EDTA, citrate, or MgSO4 Platelets were counted by the XE 5000 (Sysmex, Norderstedt, Germany) impedance and fluorescence optical technique.

RESULTS

The mean impedance platelet counts were 227.7, 197.0, and 201.1 × 10(9)/L in EDTA-, citrate-, or MgSO4-anticoagulated blood, respectively. The counts were 4.7% higher (EDTA) after 3 hours of storage but 4% lower in citrate-anticoagulated blood. The counts in magnesium samples remained stable. The MPV was 10.4 fL (EDTA), 9.5 fL (citrate), and 9.3 fL (MgSO4). EDTA samples showed cell swelling within the first 3 hours. This was lower in citrate and only marginal in magnesium samples. High activation of platelets was observed only in EDTA samples.

CONCLUSIONS

Magnesium anticoagulation might be advantageous for more reliable MPV measurements. Although platelet count is underestimated when the impedance method is used, the platelet count reveals similar results when measured by the fluorescent optical method.

Is the preoperative MPV value related to early thrombus formation in microvascular anastomosis?

OBJECTIVE

One of the most common encountered problems in free flap surgeries is anastomotic thrombosis. The mean platelet volume (MPV) may indicate the concentration of intra-platelet proactive substances and the thrombogenic potential of the platelets. MPV is used as a clinical monitoring index in routine blood counts, it has not yet been effectively used in free flap surgery.

METHODS

This study evaluates the relationship between the preoperative MPV value and anastomotic thrombus formation during the postoperative 48 hours in 32 free flap operations from September 2013 to September 2014. The mean patient age was 36.75 years. The preoperative MPV value, which was obtained from the complete blood count, was recorded and correlation of MPV and postoperative thrombus formation was investigated.

RESULTS

Four anastomotic thrombus were encountered in 34 free flaps during the postoperative 48 hours. Two of them were salvaged by performing thrombectomy and/or administration of i.v. heparin. There was no statistical relationship between MPV value and postoperative thrombus formation during 48 hours follow-up (p = 0.925).

CONCLUSION

Even though this study didn't find a correlation between preoperative MPV value and postoperative early anastomotic thrombus, it would be helpful to validate the results using multi-centre and comprehensive studies with larger patient cohorts.

Effect of training status on the changes in platelet parameters induced by short-duration exhaustive exercise

It is now well known that hemostasis is directly involved in the benefits induced by physical activity. It has recently been shown that the baseline mean platelet volume (MPV) may be a predictor of endurance performance. We aimed to explore whether platelet parameters are associated with VO2max as well as running duration and speed in a short-duration exhaustive exercise test. Thirty healthy male subjects (10 sedentary and 20 trained) performed an incremental running test until exhaustion. MPV, platelet distribution width (PDW), platelet (Plt) count, and plateletcrit (Pct) were determined before exercise, immediately after exercise and after 30' recovery. Training status did not produce any difference in the baseline levels or in the post-exercise increases found in all the parameters tested. VO2max, test duration, and running speed were not correlated with any baseline parameter. Although MPV was found to be a predictor of endurance performance in long-duration exercise, the results of the present study are consistent with the hypothesis that MPV may not be a significant marker of performance in short-duration exhaustive exercise. Likewise, more research is needed to ascertain whether platelet activation is a reliable performance predictor in other exercise settings.

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.

Increased Platelet Distribution Width Is Associated With Severity of Coronary Artery Disease in Patients With Acute Coronary Syndrome

Platelet activation plays a pivotal role in acute coronary syndrome (ACS). We investigated the relationship between platelet distribution width (PDW) and severity of coronary artery disease (CAD) in patients with ACS. A total of 502 patients with ACS were enrolled. High (n = 151) and low PDW (n = 351) groups were defined as patients having values in the third tertile (>17%) and lower 2 tertiles (≤17%). There were significantly higher Gensini score (44 [10-168] vs. 36 [2-132], P < .001), and neutrophil-lymphocyte ratio (3.1 [0.8-12.4] vs. .2.5 [0.3-13], P = .012) and baseline platelet counts were significantly lower (220 [61-623] vs. 233 [79-644] 10(3)/mm3, P = .022) in the high PDW group. The variables PDW >17%, diabetes mellitus, and myocardial infarction were found to be associated with high Gensini score (odds ratio [OR]: 1.91, 95% confidence interval [CI]: 1.27-2.88, P = .002; OR: 2.85, 95% CI: 1.91-4.25, P < .001; OR: 2.67, 95% CI:1.74-4.1, P < .001, respectively). An increased PDW (>17%) is associated with severity of CAD in patients with ACS.

Nicotinic acid/laropiprant reduces platelet count but increases mean platelet volume in patients with primary dyslipidemia

INTRODUCTION

Nicotinic acid (NA) has been associated with reduced cardiovascular morbidity and mortality. Of note, beyond its lipid-modifying actions, NA possesses a number of not yet thoroughly defined pleiotropic actions including anti-inflammatory and antithrombotic effects. As a growing body of evidence points towards mean platelet volume (MPV) and platelet distribution width (PDW) as independent risk factors for cardiovascular disease, it would be interesting to evaluate the effect of NA on these platelet indices.

MATERIAL AND METHODS

We recruited 50 consecutive patients with dyslipidemia who were treated with a conventional statin dose (10-40 mg simvastatin or 10-20 mg atorvastatin or 5-20 mg rosuvastatin) and had not achieved the low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (non-HDL-C) goal. Add-on-statin treatment with extended release (ER) NA/laropiprant (1,000/20 mg/day for the first 4 weeks followed by 2,000/40 mg/day for the next 8 weeks) was given to all patients for 3 months.

RESULTS

The ER-NA/laropiprant resulted in a 20% reduction in platelet count (from 277,150/µl (min: 163,000/µl - max: 223,400/µl) to 220,480/µl (min: 141,000/µl - max: 319,000/µl), p < 0.001), while it increased MPV by 3.5% (from 11.4 fl (min: 9.2 fl - max: 13.6 fl) to 11.8 fl (min: 9.5 fl - max: 14.1 fl), p = 0.01), without affecting PDW significantly (from 14.6 fl (min: 10.5 fl - max: 19.3 fl) to 14.5 fl (min: 11 fl - max: 21.1 fl), p = NS).

CONCLUSIONS

The NA is associated with reduced platelet count but with increased MPV, thereby raising questions regarding NA's antithrombotic and vasculoprotective properties.

Increased platelet distribution width is associated with ST-segment elevation myocardial infarction and thrombolysis failure

We investigated 2 hypotheses: (1) a relationship between platelet indices and stable coronary artery disease (CAD) and acute ST-segment elevation myocardial infarction (STEMI) and (2) a relationship between platelet indices on admission and thrombolysis outcomes in patients with STEMI. A total of 260 patients were enrolled. The white blood cell (WBC) and platelet distribution width (PDW) were found to be increased in patients with STEMI (P for both < .001). White blood cell and PDW were independent predictors of acute STEMI. Mean platelet volume (MPV) and PDW were significantly higher in the thrombolysis failure group than in the thrombolysis success group (9.9 ± 1.8 vs 9.2 ± 1.5 fL, P = .021 and 17.7 ± 1.0 vs 16.4 ± 2.1 fL, P < .001, respectively). Mean platelet volume and PDW were independent predictors of thrombolysis failure. Patients with acute STEMI had higher PDW than did patients with stable CAD. In addition, higher PDW and MPV seem to correlate with thrombolysis failure in patients with STEMI.

Effects of isotretinoin on the platelet counts and the mean platelet volume in patients with acne vulgaris

Aim. The aim of this study was to evaluate the platelet counts and the mean platelet volume in patients who received isotretinoin for the treatment of acne vulgaris. Method. A total of 110 patients were included in this retrospective study. Complete blood count parameters were recorded prior to and three-months following the treatment. Results. Both platelet counts and the mean platelet volume were significantly decreased following the treatment. No significant differences were noted on the levels of hemoglobin, hematocrit, and white blood cell count. Conclusion. Platelet counts and mean platelet volume significantly decreased following isotretinoin treatment. Since the decrease of platelet counts and the mean platelet volume was seen concomitantly, it is concluded that the effect of isotretinoin was through the suppression of bone marrow.

Mean platelet volume in patients with ischemic heart disease: meta-analysis of diagnostic studies

It is now widely acknowledged that larger platelets are biologically more active and express a greater prothrombotic potential, but there is no definitive evidence on the diagnostic accuracy role of mean platelet volume (MPV) in patients with ischemic heart disease. We performed an electronic search for articles that have assessed the diagnostic accuracy of MPV in patients admitted at the emergency department with a suspected diagnosis of ischemic heart disease, including articles in which the exact number of true-positive, false-positive, false-negative and true-negative test results could be either directly or indirectly extracted. Heterogeneity was assessed by I(2) test. The cumulative estimates and 95% confidence interval (95% CI) of sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), area under the receiver operator characteristic (ROC) curve (AUC) and diagnostic odds ratio (DOR) were calculated using a random effect model. Three studies were finally included in our analysis (mean quality score, 10.8) totaling 3577 participants (566 cases and 3011 controls). The between-study variation was high (I(2), 96.2%; P < 0.001). The pooled estimates were 0.820 (95% CI 0.786-0.851) for sensitivity, 0.461 (95% CI 0.443-0.479) for specificity, 0.932 (95% CI 0.918-0.944) for NPV and 0.222 (95% CI 0.205-0.241) for PPV and 0.652 (95% CI 0.596-0.707) for AUC. The DOR was 3.9 (95% CI 2.3-6.5), with 0.52 diagnostic accuracy. The outcome of this meta-analysis suggests that MPV does not meet the requirements for efficient triage of patients in emergency department when used as stand-alone test, whereas its combination with high-sensitive troponin immunoassays merits further investigations.

Assessment of atherosclerosis in obese adolescents: positive correlation of mean platelet volume and carotid intima media thickness

AIMS

This study aims to assess the correlation of mean platelet volume (MPV) and common carotid artery (CCA) thickness in a population of obese adolescents.

METHODS

Sixty-eight patients and 23 controls were enrolled. Anthropometric measurements, triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transpeptidase, hemoglobin, white blood cell count, platelet count, MPV and insulin resistance by homeostasis model of assessment of insulin resistance were investigated. Furthermore, CCA thickness was measured by high-resolution ultrasound.

RESULTS

MPV and the left CCA thickness were significantly higher in obese adolescents than the healthy controls. The association between MPV and left CCA was checked by linear regression analysis. MPV explained 19% of the variation in left CCA (P < 0.001). At multiple regression analysis, MPV maintained a positive association with the left CCA thickness (P = 0.002) independently of fatty liver grade, relative weight, total cholesterol and homeostasis model of assessment of insulin resistance.

CONCLUSION

MPV is significantly correlated with CCA thickness in obese adolescents.

The causal role of megakaryocyte–platelet hyperactivity in acute coronary syndromes

Platelets are causally involved in coronary artery obstruction in acute coronary syndromes (ACS). This cell type is unique to mammals and its production, which is unlike that of any other mammalian cell, involves polyploid nuclear change in the mother cell (megakaryocyte) and the production of anucleate cells with a log Gaussian distribution of volume. Platelets vary more in cellular volume than any other circulating blood element in mammals. Larger platelets are denser, contain more secretory granules, and are more reactive than their smaller counterparts. A causal relationship between the presence of large, dense, reactive platelets in the circulation and ACS is supported by many clinical studies. Furthermore, the results of two large, prospective, epidemiological studies have demonstrated that mean platelet volume was the strongest independent predictor of outcome in patients with acute myocardial infarction. Notably, evidence indicates that an increase in mean platelet volume in the pathogenesis of ACS can potentially overwhelm current therapeutics. The control system for the physiological and pathophysiological production of large platelets should, therefore, be researched. An understanding of this system might give rise to new therapeutics that could control platelet reactivity and thereby comprehensively prevent ACS.

Mean platelet volume and other platelet volume indices in patients with stable coronary artery disease and acute myocardial infarction: A case control study

Background:

Coronary artery disease is mainly caused by atherosclerosis and its complications. Platelets and their activity have an important role in initiation of atherosclerotic lesions and coronary thrombus formation. Larger platelets are enzymatically and metabolically more active and have a higher potential thrombotic ability as compared with smaller platelets.

Aims:

To study the changes in platelet volume indices and platelet count in acute myocardial infarction, stable coronary artery disease and compare them with controls to assess their usefulness in predicting coronary events.

Materials and Methods:

This was a comparative study of 128 subjects; 39 patients with acute myocardial infarction (AMI), 24 patients with stable coronary artery disease (SCAD) and 65 controls. Venous sample were drawn from AMI subjects on admission (within 4 hours of chest pain) and collected in standardized EDTA sample tubes. Platelet count and volume indices were assayed within 30 minutes of blood collection, using Sysmex KX21-N autoanalyzer. Venous samples were also drawn from SCAD on who were admitted for angiography and subject attending routine checkups.

Results:

The mean platelet volume was significantly higher in patients with AMI (9.65 ± 0.96) as compared to SCAD (9.37 ± 0.88) and controls (9.21 ± 0.58). The best cut-off values for MPV when predicting AMI and SCAD in patients were 9.25 fl (sensitivity 56.4%; specificity 45.9%) and 9.15 fl (sensitivity 54.2%; specificity 42.23%), respectively.

Conclusions:

Measurements of MPV may be of some benefit in detecting those patients at higher risk for an AMI and CAD.

Are platelet volume indices of clinical use? A multidisciplinary review

Platelet size correlates with platelet activity and can be assessed by platelet volume indices (PVI). The PVI, mean platelet volume (MPV), is universally available with routine blood counts by automated hemograms and therefore is an attractive index to study in clinical scenarios. PVI are useful in assessing the etiology of thrombocytopenia. In addition, a normal platelet distribution width in the setting of thrombocytosis is highly suggestive of a reactive etiology. Higher MPV is also associated with the presence of cardiovascular risk factors, chest pain due to acute coronary syndrome, and adverse outcome after acute coronary syndrome. Results from studies evaluating MPV in patients with peripheral artery disease, unprovoked deep vein thrombosis, and pulmonary embolism further advocate a potential role for MPV in identifying patients at high risk of thrombosis. Nevertheless, most of these data come from retrospective studies some of which have small study populations and confounding factors influencing platelet volume. Moreover, the cut-off values derived from these retrospective studies have not been validated prospectively. Despite the potential for clinical utility evident from these studies, the above-mentioned flaws together with technical problems in measuring MPV currently limit its clinical usefulness. Our review provides a perspective on PVI's potential clinical use.

Role of mean platelet volume in diagnosis of childhood acute appendicitis

Introduction. Acute appendicitis is the leading cause of abdominal pain in children requiring emergency surgical intervention. The aim of this study is to investigate the diagnostic value of MPV in early diagnosis of acute appendicitis cases in pediatric age group. Methods. This study was performed retrospectively. Three hundred five patients operated on with the diagnosis of appendicitis and pathologically found to be acute appendicitis were classified as Group 1 and 305 healthy children were classified as control Group 2. Results. One hundred ninety-seven of 305 cases in Group 1 are males (64.6%), in Group 2, 151 of 305 cases are males (49.5%). The mean MPV in Group 1 was 7.9 ± 0.9 (fL), and whereas in Group 2 was 7.7 ± 0.8 (fL). There was no statistically significant difference regarding MPV values (P > 0.05). Conclusion. In our study we detected that mean platelet volume has no diagnostic value in pediatric acute appendicitis cases.

The role of mean platelet volume in predicting thrombotic events

Studies on platelet function have accelerated and gained popularity since the advent of novel treatment modalities and techniques on atherosclerotic vascular disease, such as antiplatelet drugs and stents. Today it is widely known that platelets exert a fundamental role in inflammation in addition to their long known role in homeostasis and thrombotic events. Interaction with endothelial cells and leukocytes mediates inflammation, contributes to atherogenesis and modulates immune activity. Platelet activation which is a central factor in many arterial disorders may be triggered by multiple pathways. Platelet activation is shown as forming a larger shape, aggregation and releasing various active contents. Mean platelet volume is a marker of platelet size, function and activation. Increased mean platelet volume is shown by active and large platelets that release more thromboxane A2 than smaller ones. The aim of this review is to determine whether early detection of platelet activation via increased mean platelet volume would help to recognize the pro-inflammatory state and administer appropriate and effective treatment properly. An easily detectable marker by using a prompt and functional technique would help our approach to inflammation caused by platelets.

Novel biomarkers in diagnosing cardiac ischemia in the emergency department: a systematic review

BACKGROUND

Novel biomarkers of myocardial ischemia and inflammatory processes have the potential to improve diagnostic accuracy of acute coronary syndrome (ACS) within a shorter time interval after symptom onset.

OBJECTIVE

The objective was to review the recent literature and evaluate the evidence for use of novel biomarkers in diagnosing ACS in patients presenting with chest pain or symptoms suggestive of cardiac ischemia to the emergency department or chest pain unit.

METHODS

A literature search was performed in MEDLINE, EMBASE, Cochrane DSR, ACP Journal Club, DARE, CCTR, CMR, HTA, and NHSEED for studies from 2004 to 2010. We used the inclusion criteria: (1) human subjects, (2) peer-reviewed articles, (3) enrolled patients with ACS, acute myocardial infarction or undifferentiated signs and symptoms suggestive of ACS, and (4) English language or translated manuscripts. Two reviewers conducted a hierarchical selection and assessment using a scale developed by the International Liaison Committee on Resuscitation.

RESULTS

Out of a total 3194 citations, 58 articles evaluating 37 novel biomarkers were included for final review. Forty-one studies did not support the use of their respective biomarkers. Seventeen studies supported the use of 5 biomarkers, particularly when combined with cardiac-specific troponin: heart fatty acid-binding protein, ischemia-modified albumin, B-type natriuretic peptide, copeptin, and matrix metalloproteinase-9.

CONCLUSION

In patients presenting to the emergency department with chest pain or symptoms suggestive of cardiac ischemia, there is inadequate evidence to suggest the routine testing of novel biomarkers in isolation. However, several novel biomarkers have the potential to improve the sensitivity of diagnosing ACS when combined with cardiac-specific troponin.

Diagnostic importance of platelet parameters in patients with acute coronary syndrome admitted to a tertiary care hospital in southwest region, Saudi Arabia

OBJECTIVE

Identifying risk factors for acute coronary syndrome (ACS) is important for both diagnostic and prognostic purposes. Abnormal platelet parameters, mainly platelet count (PC), mean platelet volume (MPV) and platelet distribution width (PDW) are thought to be among these risk factors. In this study, the associations between PC, MPV and PDW and ACS were investigated in patients admitted to the tertiary care hospital in the south west region of Saudi Arabia.

MATERIALS AND METHODS

A retrospective cohort of 212 patients with the diagnosis of ACS admitted to Aseer Central Hospital during the period extending from February 1, 2008 to October 31, 2008 were included. The control group consisted of 49 matched subjects who were admitted for chest pain investigation and subsequently found to be non-cardiac chest pain after performing relevant investigations. Blood samples were taken at the time of admission for platelet parameters. Statistical analysis was made using SPSS software and P-values were considered significant if <0.05.

RESULTS

A total of 212 patients with acute coronary syndrome (80 patients with MI and 132 patients with UA) and 49 matched controls were studied. The PC was not statistically different among the three groups (283.3 ± 94.8 × 10(9) L(-1) for MI cases, 262 ± 60.8 × 10(9) L(-1) for UA cases and 275.8 ± 58.9 × 10(9) L(-1) for controls). The MPV was significantly larger in MI cases compared to controls (8.99 ± 1.5 fl vs. 8.38 ± 0.51 fl, respectively, P < 0.009), similarly, the MPV was significantly larger in UA cases compared to controls (9.23 ± 1.19 fl vs. 8.38 ± 0.51 fl, respectively, P < 0.001). The PDW was significantly higher in MI cases compared to controls (15.88 ± 1.5 fl vs. 11.96 ± 1.8 fl, respectively, P < 0.001), similarly, the PDW as also significantly larger in UA cases compared to controls (18.1 ± 18 fl vs. 11.96 ± 1.8 fl, respectively, P < 0.019).

CONCLUSION

Platelet parameters mainly MPV and PDW are readily available and relatively simple and inexpensive laboratory tests which we detected to be significantly raised in patients who have suffered an acute coronary syndrome compared with controls.

Normal range of mean platelet volume in healthy subjects: Insight from a large epidemiologic study

AIM

Mean platelet volume (MPV) in the healthy population has not been studied before. Therefore, the aim of the study was to measure MPV in normal subjects in a large cohort of Turkish adults.

METHODS

A total of 2298 subjects with a mean age of 50 (age range 18 to 92) were interviewed. Subjects who had smoking habit, diabetes, hypertension, coronary artery disease, dyslipidemia, chronic obstructive pulmonary disease, cancer, chronic use of any drugs including antiplatelets, heavy drinkers, metabolic syndrome, ejection fraction <55%, creatinine >1.4 in men and >1.1 in women, abnormal liver function tests and an abnormal TSH were excluded in a in a stepwise manner. Complete blood counts were done on the same day within 6 hours by a CELL-DYN 3700 SL analyzer (Abbott Diagnostics).

RESULTS

Three hundred twenty-six participants (204 females (63%) and 122 males (37%) with a mean age of 41 ± 16) constituted the final healthy cohort. Mean MPV of the cohort was 8.9 ± 1.4 fL. There was no significant difference among age groups regarding MPV.

CONCLUSION

Ninety-five percent of the individuals had a MPV between 7.2 and 11.7 fL. A patient having a MPV beyond this range should be evaluated carefully especially for occlusive arterial diseases.

Mean platelet volume in obese adolescents with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the accumulation of excess fat in the liver in the absence of alcohol consumption, which commonly coexists with obesity. NAFLD is associated with increased risk of atherosclerosis and insulin resistance. Mean platelet volume (MPV) is a marker of platelet activation, which is a determinant of atherosclerosis.

AIMS

The first aim of the present study was to investigate the MPV levels in obese adolescents and compare the MPV levels in patients with and without NAFLD and also with healthy controls. The second aim of this study was to evaluate the relationship between IR and MPV.

PATIENTS AND METHODS

Case records of 128 exogenous obese adolescents were retrospectively evaluated. Laboratory parameters were collected by using a computerized patient database. Insulin resistance was calculated by a homeostasis model assessment (HOMA-IR) index. Patients were divided into two groups: patients with NAFLD (Group 1) and patients without NAFLD (Group 2). Forty-seven healthy children constituted the control group.

RESULTS

MPV was significantly higher in obese adolescents than their healthy peers. Group 1 had significantly higher MPV than group 2. HOMA-IR was significantly higher in group 1 than group 2. MPV was significantly higher in patients with IR than patients without IR. There was a positive correlation between MPV and HOMA-IR. MPV was inversely correlated with HDL cholesterol and platelet count.

CONCLUSION

MPV may be used as a follow-up marker in patients with NAFLD at the point of atherosclerosis.