Heart Disease and Stroke Statistics-2016 Update: A Report From the American Heart Association

Temporal Trends and Factors Associated With Cardiovascular Drug Development, 1990 to 2012

Cardiovascular disease remains a leading cause of death, but stakeholders have recently raised concerns about the pace of innovation and investment in developing new therapeutics. Here, the authors characterized temporal trends in cardiovascular research and development over the past 2 decades and the likelihood of successful completion of pre-approval clinical trials. The authors also evaluated the reasons for discontinuation, novelty, and rates of trial results publication for cardiovascular therapies in late-stage development. Between 1990 and 2012, the number of new cardiovascular drugs entering clinical trials declined across all stages of development (p < 0.001 for linear trends). There was no evidence for a difference in probability of successful progression to the next stage of development between cardiovascular and noncardiovascular drugs. Small and medium-sized companies sponsored 43%, 38%, and 31% of new Phase 1, Phase 2, and Phase 3 trials, respectively. Roughly one-half of the drugs in Phase 3 trials were categorized as targeting a novel biological pathway. The number of cardiovascular trials sponsored by small and medium-sized companies and the number of novel drugs entering Phase 3 trials increased over time. Most drugs were discontinued in Phase 3 due to inadequate efficacy (44%) or safety issues (24%), but the Phase 3 trial results for only one-half of the discontinued drugs were published in peer-reviewed journals. These results shed light on important shifts in research and development activity and confirm the perceived challenges in cardiovascular translational research.

Heart failure therapies: new strategies for old treatments and new treatments for old strategies

Heart failure, whether acute or chronic, remains a major health care crisis affecting almost 6 million Americans and over 23 million people worldwide. Roughly half of those affected will die within 5 years, and the annual cost exceeds $30 billion in the US alone. Although medical therapy has made some modest inroads in partially stemming the heart failure tsunami, there remains a significant population for whom medication is unsuccessful or has ceased being effective; such patients can benefit from heart transplantation or mechanical circulatory support. Indeed, in the past quarter century (and as covered in Cardiovascular Pathology over those years), significant improvements in pathologic understanding and in engineering design have materially enhanced the toolkit of options for such refractory patients. Mechanical devices, whether total artificial hearts or ventricular assist devices, have been reengineered to reduce complications and basic wear and tear. Transplant survival has also been extended through a better comprehension of and improved therapies for transplant vasculopathy and antibody-mediated rejection. Here we review the ideas and treatments from the last 25 years and highlight some of the new directions in nonpharmacologic heart failure therapy.

Anatomopathological changes of the cardiac conduction system in sudden cardiac death, particularly in infants: advances over the last 25 years

Sudden cardiac death (SCD) is defined as the unexpected death without an obvious noncardiac cause that occurs within 1 h of witnessed symptom onset (established SCD) or within 24 h of unwitnessed symptom onset (probable SCD). In the United States, its incidence is 69/100,000 per year. Dysfunctions of the cardiac conduction and autonomic nervous systems are known to contribute to SCD pathogenesis, even if most clinicians and cardiovascular pathologists lack experience with detailed examination of the cardiac conduction system and fail to recognize lesions that are crucial to explain the SCD itself. In this review, we sought to describe the advances over the last 25 years in the study of the anatomopathological changes of the conducting tissue, in SCD, in mature hearts and particularly in sudden infant death syndrome (SIDS) and sudden intrauterine unexpected death syndrome (SIUDS), through the articles published in our journal Cardiovascular Pathology (CVP). We carried out an extensive Medline search to retrieve and review all articles published in CVP in which the sudden unexpected death of one or more subjects believed healthy was reported, especially if associated with lesions of the conducting tissue in settings that revealed no other explained causes of death, particularly in infants and fetuses. The cardiac conduction findings of resorptive degeneration, His bundle dispersion, Mahaim fibers, cartilaginous meta-hyperplasia, persistent fetal dispersion, left-sided His bundle, septation of the bifurcation, atrioventricular node dispersion, sinus node hypoplasia, Zahn node, His bundle hypoplasia, atrioventricular node, and His bundle dualism were similarly detected in SIDS and SIUDS victims.

Exercise Prescription for the Athlete with Cardiomyopathy

Inherited cardiomyopathies have highly variable expression in terms of symptoms, functional limitations, and disease severity. Associated risk of sudden cardiac death is also variable. International guidelines currently recommend restriction of all athletes with cardiomyopathy from participation in competitive sports. While the guidelines are necessarily conservative because predictive risk factors for exercise-triggered SCD have not been clearly identified, the risk is clearly not uniform across all athletes and all sports. The advent of implantable cardioverter defibrillators, automated external defibrillators, and successful implementation of emergency action plans may safely mitigate risk of sudden cardiac death during physical activity. An individualized approach to risk stratification of athletes that recognizes patient autonomy may allow many individuals with cardiomyopathies to safely train and compete.

Dual antiplatelet therapy is associated with prolonged survival after lower extremity revascularization

BACKGROUND

Dual antiplatelet therapy (DAPT) after coronary stenting prolongs survival by preventing both in-stent thrombosis and other cardiovascular atherothrombotic events. Patients with peripheral artery disease (PAD) typically have a heavy burden of unrevascularized coronary artery disease and also stand to benefit from increased atherothrombotic protection with DAPT. The potential benefit of DAPT compared with aspirin alone in patients with PAD is not well described.

METHODS

We identified all patients undergoing an initial elective lower extremity revascularization (bypass or endovascular) from 2003 to 2016 in the Vascular Quality Initiative registry discharged on aspirin or aspirin plus a thienopyridine antiplatelet agent (DAPT). We first estimated models predicting the likelihood of receiving DAPT and then used inverse probability weighting to account for baseline differences in the likelihood of receiving DAPT and compared late survival. For sensitivity analysis, we also performed Cox proportion hazard modeling on the unweighted cohorts and generated adjusted survival curves.

RESULTS

We identified 57,041 patients undergoing lower extremity revascularization (28% bypass). Of 15,985 bypasses (69% for critical limb ischemia [CLI]), 38% were discharged on DAPT. Of 41,056 endovascular interventions (39% for CLI), 69% were discharged on DAPT. Analyses using inverse probability weighting demonstrated a small survival benefit to DAPT at 1 year for bypass (93% vs 92% [P = .001]) and endovascular interventions (93% vs 92% [P = .005]) that was sustained through 5 years of follow-up (bypass, 80% vs 78% [P = .004]; endovascular, 76% vs 73% [P = .002]). When stratified by severity of PAD, DAPT had a survival benefit for patients with CLI undergoing bypass (5 years, 70% vs 66% [P = .04]) and endovascular intervention (5 years, 71% vs 67% [P = .01]) but not for patients with claudication (bypass, 89% vs 88% [P = .36]; endovascular, 87% vs 85% [P = .46]). The protective effect of DAPT was similar when using Cox proportional hazard models after bypass (hazard ratio, 0.81 [95% confidence interval, 0.72-0.90]) and endovascular intervention (hazard ratio, 0.89 [95% confidence interval, 0.83-0.95]).

CONCLUSIONS

DAPT at time of discharge was associated with prolonged survival for patients with CLI undergoing lower extremity revascularization but not for those with claudication. Further research is needed to quantify the risks associated with DAPT and to identify subgroups at increased risk of thrombotic and bleeding complications to guide medical management of patients with PAD.

The role of active brown adipose tissue (aBAT) in lipid metabolism in healthy Chinese adults

Background

The prevalence of dyslipidemia in China was increased over the last several years. Studies have shown that the activity of aBAT is related to the lipid metabolism. In this study, we analyzed blood lipid level in tumor-free healthy Chinese adults in order to determine the role of aBAT in lipid metabolism.

Methods

We retrospectively analyzed the factors that affect the blood lipid level in 717 tumor-free healthy adults who received blood lipid measurement and PET/CT scan by multivariate regression analysis. We also determined the role of aBAT on lipid profile by case–control study.

Results

(1) Our results showed that 411 (57.3 %) subjects had dyslipidemia. The prevalence of the subjects with hypercholesteremia, hypertriglyceridemia, low high-density lipoprotein cholesterol and high low-density lipoprotein cholesterol was 9.5 %, 44.4 %, 30.8 % and 1.4 %, respectively. Multivariate logistic regression analysis with dyslipidemia as the dependent variable showed that body mass index (BMI) and smoking are independent risk factors for dyslipidemia (OR > 1, P < 0.05), while the presence of aBAT is the independent protective factor for dyslipidemia (OR < 1, P < 0.05). (2) The incidence of aBAT was 1.81 %. Subjects with aBAT had significantly lower serum triglyceride and higher serum high-density lipoprotein cholesterol than the subjects without aBAT. The serum total cholesterol and low-density lipoprotein cholesterol were not significantly different between the subjects with aBAT and those without aBAT.

Conclusions

Dyslipidemia is caused by multiple factors and the presence of aBAT is a protective factor for dyslipidemia in healthy Chinese adults.

Induction of Therapeutic Hypothermia During Out-of-Hospital Cardiac Arrest Using a Rapid Infusion of Cold Saline: The RINSE Trial (Rapid Infusion of Cold Normal Saline)

BACKGROUND

Patients successfully resuscitated by paramedics from out-of-hospital cardiac arrest often have severe neurologic injury. Laboratory and observational clinical reports have suggested that induction of therapeutic hypothermia during cardiopulmonary resuscitation (CPR) may improve neurologic outcomes. One technique for induction of mild therapeutic hypothermia during CPR is a rapid infusion of large-volume cold crystalloid fluid.

METHODS

In this multicenter, randomized, controlled trial we assigned adults with out-of-hospital cardiac arrest undergoing CPR to either a rapid intravenous infusion of up to 2 L of cold saline or standard care. The primary outcome measure was survival at hospital discharge; secondary end points included return of a spontaneous circulation. The trial was closed early (at 48% recruitment target) due to changes in temperature management at major receiving hospitals.

RESULTS

A total of 1198 patients were assigned to either therapeutic hypothermia during CPR (618 patients) or standard prehospital care (580 patients). Patients allocated to therapeutic hypothermia received a mean (SD) of 1193 (647) mL cold saline. For patients with an initial shockable cardiac rhythm, there was a decrease in the rate of return of a spontaneous circulation in patients who received cold saline compared with standard care (41.2% compared with 50.6%, P=0.03). Overall 10.2% of patients allocated to therapeutic hypothermia during CPR were alive at hospital discharge compared with 11.4% who received standard care (P=0.71).

CONCLUSIONS

In adults with out-of-hospital cardiac arrest, induction of mild therapeutic hypothermia using a rapid infusion of large-volume, intravenous cold saline during CPR may decrease the rate of return of a spontaneous circulation in patients with an initial shockable rhythm and produced no trend toward improved outcomes at hospital discharge.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01173393.

Associations between blood glucose level and outcomes of adult in-hospital cardiac arrest: a retrospective cohort study

BACKGROUND

We intended to analyse the associations between blood glucose (BG) level and clinical outcomes of in-hospital cardiac arrest (IHCA).

METHODS

We conducted a retrospective observational study in a single medical centre and evaluated patients who experienced IHCA between 2006 and 2014. We used multivariable logistic regression analysis to study associations between independent variables and outcomes. We calculated the mean BG level for each patient by averaging the maximum and minimum BG levels in the first 24 h after arrest, and we used mean BG level for our final analysis.

RESULTS

We included a total of 402 patients. Of these, 157 patients (39.1 %) had diabetes mellitus (DM). The average mean BG level was 209.9 mg/dL (11.7 mmol/L). For DM patients, a mean BG level between 183 and 307 mg/dL (10.2-17.1 mmol/L) was significantly associated with favourable neurological outcome (odds ratio [OR] 2.71, 95 % confidence interval [CI] 1.18-6.20; p value = 0.02); a mean BG level between 147 and 317 mg/dL (8.2-17.6 mmol/L) was significantly associated with survival to hospital discharge (OR 2.38, 95 % CI 1.26-4.53; p value = 0.008). For non-DM patients, a mean BG level between 143 and 268 mg/dL (7.9-14.9 mmol/L) was significantly associated with survival to hospital discharge (OR 2.93, 95 % CI 1.62-5.40; p value < 0.001).

CONCLUSIONS

Mean BG level in the first 24 h after cardiac arrest was associated with neurological outcome for IHCA patients with DM. For neurological and survival outcomes, the optimal BG range may be higher for patients with DM than for patients without DM.

Trends in the epidemiology of cardiovascular disease in the UK

Cardiovascular disease (CVD) mortality in the UK is declining; however, CVD burden comes not only from deaths, but also from those living with the disease. This review uses national datasets with multiple years of data to present secular trends in mortality, morbidity, and treatment for all CVD and specific subtypes within the UK. We produced all-ages and premature age-standardised mortality rates by gender, standardised to the 2013 European Standard Population, using data from the national statistics agencies of the UK. We obtained data on hospital admissions from the National Health Service records, using the main diagnosis. Prevalence data come from the Quality and Outcome Framework and national surveys. Total CVD mortality declined by 68% between 1980 and 2013 in the UK. Similar decreases were seen for coronary heart disease and stroke. Coronary heart disease prevalence has remained constant at around 3% in England and 4% in Scotland, Wales, and Northern Ireland. Hospital admissions for all CVD increased by over 46 000 between 2010/2011 and 2013/2014, with more than 36 500 of these increased admissions for men. Hospital admission trends vary by country and CVD condition. CVD prescriptions and operations have increased over the last decade. CVD mortality has declined notably for both men and women while hospital admissions have increased. CVD prevalence shows little evidence of change. This review highlights that improvements in the burden of CVD have not occurred equally between the four constituent countries of the UK, or between men and women.

Paraffin processing of stented arteries using a postfixation dissolution of metallic and polymeric stents

Studying the morphology of the arterial response to endovascular stent implantation requires embedding the explanted stented artery in rigid materials such as poly(methyl methacrylate) to enable sectioning through both the in situ stent and the arterial wall, thus maintaining the proper anatomic relationships. This is a laborious, time-consuming process. Moreover, the technical quality of stained plastic sections is typically suboptimal and, in some cases, precludes immunohistochemical analysis. Here we describe a novel technique for dissolution of metallic and plastic stents that is compatible with subsequent embedding of "destented" arteries in paraffin, fine sectioning, major staining protocols, and immunohistochemistry.

Endothelial cell metabolism: A novel player in atherosclerosis? Basic principles and therapeutic opportunities

Atherosclerosis is a leading cause of morbidity and mortality in Western society. Despite improved insight into disease pathogenesis and therapeutic options, additional treatment strategies are required. Emerging evidence highlights the relevance of endothelial cell (EC) metabolism for angiogenesis, and indicates that EC metabolism is perturbed when ECs become dysfunctional to promote atherogenesis. In this review, we overview the latest insights on EC metabolism and discuss current knowledge on how atherosclerosis deregulates EC metabolism, and how maladaptation of deregulated EC metabolism can contribute to atherosclerosis progression. We will also highlight possible therapeutic avenues, based on targeting EC metabolism.

Stroke prevention in atrial fibrillation

Atrial fibrillation is found in a third of all ischaemic strokes, even more after post-stroke atrial fibrillation monitoring. Data from stroke registries show that both unknown and untreated or under treated atrial fibrillation is responsible for most of these strokes, which are often fatal or debilitating. Most could be prevented if efforts were directed towards detection of atrial fibrillation before stroke occurs, through screening or case finding, and treatment of all patients with atrial fibrillation at increased risk of stroke with well-controlled vitamin K antagonists or non-vitamin K antagonist anticoagulants. The default strategy should be to offer anticoagulant thromboprophylaxis to all patients with atrial fibrillation unless defined as truly low risk by simple validated risk scores, such as CHA2DS2-VASc. Assessment of bleeding risk using the HAS-BLED score should focus attention on reversible bleeding risk factors. Finally, patients need support from physicians and various other sources to start anticoagulant treatment and to ensure adherence to and persistence with treatment in the long term.

Diagnostic Performance of Treadmill Exercise Cardiac Magnetic Resonance: The Prospective, Multicenter Exercise CMR's Accuracy for Cardiovascular Stress Testing (EXACT) Trial

Background

Stress cardiac magnetic resonance (CMR) has typically involved pharmacologic agents. Treadmill CMR has shown utility in single‐center studies but has not undergone multicenter evaluation.

Methods and Results

Patients referred for treadmill stress nuclear imaging (SPECT) were prospectively enrolled across 4 centers. After rest ^99mTc SPECT, patients underwent resting cine CMR. In‐room stress was then performed using an MR‐compatible treadmill with continuous 12‐lead electrocardiogram monitoring. At peak stress, ^99mTc was injected, and patients rapidly returned to the MR scanner isocenter for real‐time, free‐breathing stress cine and perfusion imaging. After recovery, cine and rest perfusion followed by late gadolinium enhancement acquisitions concluded CMR imaging. Stress SPECT was then acquired in adjacent nuclear laboratories. A subset of patients not referred for invasive coronary angiography within 2 weeks of stress underwent coronary computed tomography angiography. Angiographic data available in 94 patients showed sensitivity of 79%, specificity of 99% for exercise CMR with positive predictive value of 92% and negative predictive value of 96%. Agreement between treadmill stress CMR and angiography was strong (κ=0.82), and moderate between SPECT and angiography (κ=0.46) and CMR versus SPECT (κ=0.48).

Conclusions

The multicenter EXACT trial indicates excellent diagnostic value of treadmill stress CMR in typical patients referred for exercise SPECT.

The P4 Health Spectrum - A Predictive, Preventive, Personalized and Participatory Continuum for Promoting Healthspan

Chronic diseases (i.e., noncommunicable diseases), mainly cardiovascular disease, cancer, respiratory diseases and type-2-diabetes, are now the leading cause of death, disability and diminished quality of life on the planet. Moreover, these diseases are also a major financial burden worldwide, significantly impacting the economy of many countries. Healthcare systems and medicine have progressively improved upon the ability to address infectious diseases and react to adverse health events through both surgical interventions and pharmacology; we have become efficient in delivering reactive care (i.e., initiating interventions once an individual is on the verge of or has actually suffered a negative health event). However, with slowly progressing and often 'silent' chronic diseases now being the main cause of illness, healthcare and medicine must evolve into a proactive system, moving away from a merely reactive approach to care. Minimal interactions among the specialists and limited information to the general practitioner and to the individual receiving care lead to a fragmented health approach, non-concerted prescriptions, a scattered follow-up and a suboptimal cost-effectiveness ratio. A new approach in medicine that is predictive, preventive, personalized and participatory, which we label here as "P4" holds great promise to reduce the burden of chronic diseases by harnessing technology and an increasingly better understanding of environment-biology interactions, evidence-based interventions and the underlying mechanisms of chronic diseases. In this concept paper, we propose a 'P4 Health Continuum' model as a framework to promote and facilitate multi-stakeholder collaboration with an orchestrated common language and an integrated care model to increase the healthspan.

Cardiovascular Health Status by Occupational Group - 21 States, 2013

Cardiovascular disease (CVD) accounts for one of every three deaths in the United States, making it the leading cause of mortality in the country (1). The American Heart Association established seven ideal cardiovascular health behaviors or modifiable factors to improve CVD outcomes in the United States. These cardiovascular health metrics (CHMs) are 1) not smoking, 2) being physically active, 3) having normal blood pressure, 4) having normal blood glucose, 5) being of normal weight, 6) having normal cholesterol levels, and 7) eating a healthy diet (2). Meeting six or all seven CHMs is associated with a lower risk for all-cause, CVD, and ischemic heart disease mortalities compared with the risk to persons who meet none or only one CHM (3). Fewer than 2% of U.S. adults meet all seven of the American Heart Association's CHMs (4). Cardiovascular morbidity and mortality account for an estimated annual $120 billion in lost productivity in the workplace; thus, workplaces are viable settings for effective health promotion programs (5). With over 130 million employed persons in the United States, accounting for about 55% of all U.S. adults, the working population is an important demographic group to evaluate with regard to cardiovascular health status. To determine if an association between occupation and CHM score exists, CDC analyzed data from the 2013 Behavioral Risk Factor Surveillance System (BRFSS) industry and occupation module, which was implemented in 21 states. Among all occupational groups, community and social services employees (14.6%), transportation and material moving employees (14.3%), and architecture and engineering employees (11.6%) had the highest adjusted prevalence of meeting two or fewer CHMs. Transportation and material moving employees also had the highest prevalence of "not ideal" ("0" [i.e., no CHMs met]) scores for three of the seven CHMs: physical activity (54.1%), blood pressure (31.9%), and weight (body mass index [BMI]; 75.5%). Disparities in cardiovascular health status exist among U.S. occupational groups, making occupation an important consideration in employer-sponsored health promotion activities and allocation of prevention resources.

Trends in Heart Disease Mortality among Mississippi Adults over Three Decades, 1980-2013

Heart disease (HD) remains the leading cause of death among Mississippians; however, despite the importance of the condition, trends in HD mortality in Mississippi have not been adequately explored. This study examined trends in HD mortality among adults in Mississippi from 1980 through 2013 and further examined these trends by race and sex. We used data from Mississippi Vital Statistics (1980-2013) to calculate age-adjusted HD mortality rates for Mississippians age 25 or older. Cases were identified using underlying cause of death codes from the International Classification of Diseases, Ninth Revision (ICD-9: 390-398, 402, 404-429) and Tenth Revision (ICD-10), including I00-I09, I11, I13, and I20-I51. Joinpoint software was used to calculate the average annual percent change in HD mortality rates for the overall population and by race and sex. Overall, the age-adjusted HD mortality rate among Mississippi adults decreased by 36.5% between 1980 and 2013, with an average annual percent change of -1.60% (95% CI -2.00 to -1.30). This trend varied across subgroups: HD mortality rates experienced an average annual change of -1.34% (95% CI -1.98 to -0.69) for black adults; -1.60% (95% CI -1.74 to -1.46) for white adults; -1.30% (95% CI -1.50 to -1.10) for all women, and -1.90% (95% -2.20 to -1.50) for all men. From 1980 to 2013, there was a continuous decrease in HD mortality among adult Mississippians. However, the magnitude of this reduction differed by race and sex.

Prevalence, awareness, treatment, control of type 2 diabetes mellitus and risk factors in Chinese rural population: the RuralDiab study

The study aimed to investigate prevalence, awareness, treatment and control of type 2 diabetes mellitus (T2DM), and to explore potential risk factors in rural areas of China. A total of 16413 individuals aged 18–74 years in rural districts were recruited from the Rural Diabetes, Obesity and Lifestyle (RuralDiab) study for the epidemiological research. Meanwhile, a meta-analysis including 7 published studies was conducted to validate the result of the cross-sectional study. The rates of crude and age-standardized prevalence, awareness, treatment and control of T2DM were 12.19%, 67.00%, 62.35%, 22.20% and 6.98%, 60.11%, 54.85%, 18.77%, respectively. The prevalence, awareness, treatment and control of T2DM displayed increased trends with age (P_trend < 0.01) and were strongly associated with education, drinking, more vegetable and fruit intake, physical activity, family history of diabetes, body mass index (BMI). The results of this meta-analysis showed that the pooled prevalence, awareness, treatment and control of T2DM in China countryside were 7.3% (5.3–9.4%), 57.3% (36.9–77.6%), 48.4% (32.4–64.5%) and 21.0% (9.9–32.1%), respectively. The prevalence of T2DM was high with inadequate awareness, treatment and control of T2DM in China rural areas. Healthy lifestyles should be advocated to reduce prevalence and improve awareness, treatment, and control of T2DM in Chinese rural residents.

Morphology, Clinicopathologic Correlations, and Mechanisms in Heart Valve Health and Disease

The clinical and pathological features of the most frequent intrinsic structural diseases that affect the heart valves are well established, but heart valve disease mechanisms are poorly understood, and effective treatment options are evolving. Major advances in the understanding of the structure, function and biology of native valves and the pathobiology, biomaterials and biomedical engineering, and the clinical management of valvular heart disease have occurred over the past several decades. This communication reviews contemporary considerations relative to the pathology of valvular heart disease, including (1) clinical significance and epidemiology of valvular heart disease; (2) functional and dynamic valvular macro-, micro- and ultrastructure; (3) causes, morphology and mechanisms of human valvular heart disease; and (4) pathologic considerations in valve replacement, repair and, potentially, regeneration of the heart valves.

Red blood cell distribution width independently predicts medium-term mortality and major adverse cardiac events after an acute coronary syndrome

BACKGROUND

The value of red blood cell distribution width (RDW), a simple and inexpensive measure of anisocytosis, has been associated with the outcome of many human chronic disorders. Therefore, this retrospective study was aimed to investigate whether RDW may be associated with medium-term mortality and major adverse cardiac events (MACE) after an acute coronary syndrome (ACS).

METHODS

A total number of 979 patients diagnosed with ACS were enrolled from June 2014 to November 2014, and followed-up until June 2015.

RESULTS

The RDW value in patients with 3-month MACE and in those who died was significantly higher than that of patients without 3-month MACE (13.3% vs. 14.0%; P<0.001) and those who were still alive at the end of follow-up (13.4% vs. 14.4%; P<0.001). In univariate analysis, RDW was found to be associated with 3-month MACE [odds ratio (OR), 1.70; 95% CI, 1.44-2.00, P<0.001]. In multivariate analysis, RDW remained independently associated with 3-month MACE (adjusted OR, 1.36; 95% CI, 1.19-1.55; P<0.001) and death (adjusted OR, 1.34; 95% CI, 1.05-1.71; P=0.020). The accuracy of RDW for predicting 3-month MACE was 0.67 (95% CI, 0.66-0.72; P<0.001). The most efficient discriminatory RDW value was 14.8%, which was associated with 3.8 (95% CI, 2.6-5.7; P<0.001) higher risk of 3-month MACE. Patients with RDW >14.8% exhibited a significantly short survival than those with RDW ≤14.8% (331 vs. 465 days; P<0.001).

CONCLUSIONS

The results of this study confirm that RDW may be a valuable, easy and inexpensive parameter for stratifying the medium-term risk in patients with ACS.

Can Prediction of Functional Outcome after Stroke Be Improved by Adding Fibrinogen to Prognostic Model?

BACKGROUND

Several studies demonstrated that elevated plasma fibrinogen level is associated with poor functional outcome after ischemic stroke. It remains, however, unclear if prediction of functional outcome after stroke can be improved by adding fibrinogen to prognostic model. We aimed to determine the prognostic value of plasma fibrinogen for the prediction of functional outcome after ischemic stroke.

METHODS

We retrospectively analyzed the data of 727 ischemic stroke patients (median age: 70; 48% men). The functional outcome was assessed 1 month after stroke onset using modified Rankin Scale. Unfavorable outcome was defined as modified Rankin Scale score higher than 2. Using C-statistic and reclassification measures (net reclassification improvement-NRI and integrated discrimination improvement-IDI), we compared the predictive abilities of 2 models. The first model contained stroke severity and age, and the second one included fibrinogen in addition.

RESULTS

After adjusting for age and stroke severity, plasma fibrinogen level higher than 2.95 g/L was associated with unfavorable outcome (OR: 1.80, 95% CI: 1.20-2.72, P < .01). The addition of fibrinogen did not lead to an improvement in predictive ability of the model. C-statistic did not differ between models (.90 versus .90, P = .34). The categorical NRI was .01 (P = .66) and the IDI was .006 (P = .08).

CONCLUSIONS

The addition of fibrinogen to predictive model including age and stroke severity does not improve discrimination between favorable and unfavorable outcomes after ischemic stroke.

Adaptation of the cerebrocortical circulation to carotid artery occlusion involves blood flow redistribution between cortical regions and is independent of eNOS

Cerebral circulation is secured by feed-forward and feed-back control pathways to maintain and eventually reestablish the optimal oxygen and nutrient supply of neurons in case of disturbances of the cardiovascular system. Using the high temporal and spatial resolution of laser-speckle imaging we aimed to analyze the pattern of cerebrocortical blood flow (CoBF) changes after unilateral (left) carotid artery occlusion (CAO) in anesthetized mice to evaluate the contribution of macrovascular (circle of Willis) vs. pial collateral vessels as well as that of endothelial nitric oxide synthase (eNOS) to the cerebrovascular adaptation to CAO. In wild-type mice CoBF reduction in the left temporal cortex started immediately after CAO, reaching its maximum (-26%) at 5-10 s. Thereafter, CoBF recovered close to the preocclusion level within 30 s indicating the activation of feed-back pathway(s). Interestingly, the frontoparietal cerebrocortical regions also showed CoBF reduction in the left (-17-19%) but not in the right hemisphere, although these brain areas receive their blood supply from the common azygos anterior cerebral artery in mice. In eNOS-deficient animals the acute CoBF reduction after CAO was unaltered, and the recovery was even accelerated compared with controls. These results indicate that 1) the Willis circle alone is not sufficient to provide an immediate compensation for the loss of one carotid artery, 2) pial collaterals attenuate the ischemia of the temporal cortex ipsilateral to CAO at the expense of the blood supply of the frontoparietal region, and 3) eNOS, surprisingly, does not play an important role in this CoBF redistribution.

Atherogenic index of plasma and the gamma gap: Considerations by physical activity

BACKGROUND

Atherogenic index of plasma (AIP), calculated as LOG10(triglycerides/high-density lipoprotein-cholesterol), is utilized to predict risk of cardiovascular disease. An elevated (≥3.1g/dL) gamma gap (total protein (g/dL) - albumin (g/dL)) is associated with cardiovascular disease. No previous studies have evaluated the association between AIP and the gamma gap. Consequentially, the purpose of this study was to explore this association, with considerations by moderate-to-vigorous physical activity (MVPA), which may plausibly be associated with both AIP and gamma gap.

METHODS

Data from the 1999-2006 National Health and Nutrition Examination Survey were used (N=6681 adults 20-85yrs). AIP was assessed from a blood sample, physical activity was self-reported via a survey assessing leisure-time physical activity over the previous 30-days, and the gamma gap was evaluated by subtracting albumin from total protein using the Hitachi Model 704 multichannel analyzer.

RESULTS

Participants with an elevated (>0.24 vs. <0.25mmol/L) AIP had a 27% increased odds of having an elevated gamma gap (odds ratio [OR]=1.27; 95% CI: 1.04-1.55; P=0.01; N=6681). AIP was significantly, positively associated with increased odds for an elevated gamma gap among those meeting MVPA guidelines (for a 1mmol/L increase in AIP: OR=2.57; 95% CI: 1.54-4.27; P<0.001; N=2688) and those not meeting MVPA guidelines (for a 1mmol/L increase in AIP: OR=1.70; 95% CI: 1.19-2.42; P=0.004; N=3993).

CONCLUSION

AIP and gamma gap are positively associated, however MVPA does not appear to influence this association.

Depressive Symptoms among Patients with Heart Failure in Korea: An Integrative Review

This integrative review was conducted to examine studies reporting depressive symptoms among patients with heart failure (HF) in Korea. An extensive search with both English and Korean search terms was conducted using six electronic databases. Publications were screened by both authors independently, and 10 articles meeting the inclusion criteria were reviewed. All 10 studies were data-based, quantitative, and descriptive in nature. In all studies, depressive symptoms were measured at only one point in time. The prevalence of depression reported in these studies ranged from 24% to 68%. Heterogeneity in the study samples and measures of depression was noted. Depressive symptoms have received limited attention in research with HF patients in Korea. Additional studies, especially longitudinal studies and intervention studies, are needed to assess depressive symptoms and to test the effects of pharmacological and non-pharmacological interventions on depression among patients with HF in Korea. Clinicians need to screen patients with HF for depressive symptoms using validated measures and provide proper treatment for those who are depressed.

Impact of empagliflozin in patients with diabetes and heart failure

Heart failure (HF) is a common disease with increased risk for mortality and morbidity among patients with type 2 diabetes mellitus (T2DM). Optimal glycemic control in this patient population is challenging as many available therapies can potentially exacerbate symptoms of HF. Empagliflozin is one in a novel class of agents, the sodium glucose co-transporter 2 (SGLT2) inhibitors, that lowers blood glucose by increasing urinary glucose excretion and improves glycemic control and lowers body weight and blood pressure. In the recent EMPA-REG OUTCOME trial, empagliflozin was shown to improve cardiovascular outcomes in patients with T2DM and established cardiovascular risk where it reduced HF hospitalizations and cardiovascular death, with a consistent benefit among patients both with and without baseline HF. Here, we review the empagliflozin data on HF outcomes and discuss potential mechanisms for its benefits in HF with a focus on the potentially significant impact that empagliflozin may have on the care of patients with T2DM and HF in the future.

Normalization of NAD+ Redox Balance as a Therapy for Heart Failure

BACKGROUND

Impairments of mitochondrial function in the heart are linked intricately to the development of heart failure, but there is no therapy for mitochondrial dysfunction.

METHODS

We assessed the reduced/oxidized ratio of nicotinamide adenine dinucleotide (NADH/NAD(+) ratio) and protein acetylation in the failing heart. Proteome and acetylome analyses were followed by docking calculation, mutagenesis, and mitochondrial calcium uptake assays to determine the functional role of specific acetylation sites. The therapeutic effects of normalizing mitochondrial protein acetylation by expanding the NAD(+) pool also were tested.

RESULTS

Increased NADH/NAD(+) and protein hyperacetylation, previously observed in genetic models of defective mitochondrial function, also are present in human failing hearts as well as in mouse hearts with pathologic hypertrophy. Elevation of NAD(+) levels by stimulating the NAD(+) salvage pathway suppressed mitochondrial protein hyperacetylation and cardiac hypertrophy, and improved cardiac function in responses to stresses. Acetylome analysis identified a subpopulation of mitochondrial proteins that was sensitive to changes in the NADH/NAD(+) ratio. Hyperacetylation of mitochondrial malate-aspartate shuttle proteins impaired the transport and oxidation of cytosolic NADH in the mitochondria, resulting in altered cytosolic redox state and energy deficiency. Furthermore, acetylation of oligomycin-sensitive conferring protein at lysine-70 in adenosine triphosphate synthase complex promoted its interaction with cyclophilin D, and sensitized the opening of mitochondrial permeability transition pore. Both could be alleviated by normalizing the NAD(+) redox balance either genetically or pharmacologically.

CONCLUSIONS

We show that mitochondrial protein hyperacetylation due to NAD(+) redox imbalance contributes to the pathologic remodeling of the heart via 2 distinct mechanisms. Our preclinical data demonstrate a clear benefit of normalizing NADH/NAD(+) imbalance in the failing hearts. These findings have a high translational potential as the pharmacologic strategy of increasing NAD(+) precursors are feasible in humans.

The Unchartered Frontier: Preventive Cardiology Between the Ages of 15 and 35 Years

It is well established that atherosclerosis, the pathological basis of cardiovascular disease (CVD), begins in childhood and progresses steadily between the ages of 15 to 35 years. These adolescent and young adult years are also marked by significant physiological, psychological, and sociodemographic changes that impact both CVD risk factor development and CVD prevention and treatment strategies. In this review, we highlight the importance of the primordial prevention of CVD risk factors before they ever occur and the primary prevention of CVD by treating CVD risk factors in this age group. Although the long time to first CVD event for most young people precludes the availability of clinical trials with hard end-points, findings from epidemiology, health psychology, health services research, and clinical trials with surrogate endpoints are discussed to inform an evidence-based approach to CVD prevention in adolescents and young adults.

Association of Weight and Body Composition on Cardiac Structure and Function in the ARIC Study (Atherosclerosis Risk in Communities)

BACKGROUND

Obesity increases cardiovascular risk. However, the extent to which various measures of body composition are associated with abnormalities in cardiac structure and function, independent of comorbidities commonly affecting obese individuals, is not clear. This study sought to examine the relationship between body mass index, waist circumference, and percent body fat with conventional and advanced measures of cardiac structure and function.

METHODS AND RESULTS

We studied 4343 participants of the ARIC study (Atherosclerosis Risk in Communities) who were aged 69 to 82 years, free of coronary heart disease and heart failure, and underwent comprehensive echocardiography. Increasing body mass index, waist circumference, and body fat were associated with greater left ventricular (LV) mass and left atrial volume indexed to height(2.7) in both men and women (P<0.001). In women, all 3 measures were associated with abnormal LV geometry, and increasing waist circumference and body fat were associated with worse global longitudinal strain, a measure of LV systolic function. In both sexes, increasing body mass index was associated with greater right ventricular end-diastolic area and worse right ventricular fractional area change (P≤0.001). We observed similar associations for both waist circumference and percent body fat.

CONCLUSIONS

In a large, biracial cohort of older adults free of clinically overt coronary heart disease or heart failure, obesity was associated with subclinical abnormalities in cardiac structure in both men and women and with adverse LV remodeling and impaired LV systolic function in women. These data highlight the association of obesity and subclinical abnormalities of cardiac structure and function, particularly in women.

Should apolipoprotein B replace LDL cholesterol as therapeutic targets are lowered?

PURPOSE OF REVIEW

The success of LDL cholesterol (LDL-C) as a predictor of atherosclerotic cardiovascular disease and a therapeutic target is indisputable. Apolipoprotein B (apoB) is a more contemporary and physiologically relevant measure of atherogenic lipoproteins. This report summarizes recent comparisons of apoB and LDL-C as biomarkers of cardiovascular risk.

RECENT FINDINGS

Multiple recent reports have found that LDL-C methods perform poorly at low concentrations (<70 mg/dl). Several meta-analyses from randomized controlled trials and large prospective observational studies have found that apoB and LDL-C provide equivalent information on risk of cardiovascular disease. More innovative analyses have asserted that apoB is a superior indicator of actual risk when apoB and LDL-C disagree.

SUMMARY

ApoB is more analytically robust and standardized biomarker than LDL-C. Large population studies have found that apoB is at worst clinically equivalent to LDL-C and likely superior when disagreement exists. Realistically, many obstacles prevent the wide spread adoption of apoB and for now providers and their patients must weigh the costs and benefits of apoB.

Nafamostat mesilate improves function recovery after stroke by inhibiting neuroinflammation in rats

Inflammation plays an important role in stroke pathology, making it a promising target for stroke intervention. Nafamostat mesilate (NM), a wide-spectrum serine protease inhibitor, is commonly used for treating inflammatory diseases, such as pancreatitis. However, its effect on neuroinflammation after stroke was unknown. Hence, the effects of NM on the inflammatory response post stroke were characterized. After transient middle cerebral artery occlusion (tMCAO) in rats, NM reduced the infarct size, improved behavioral functions, decreased the expression of proinflammatory mediators (TNF-α, IL-1β, iNOS and COX-2) in a time-dependent manner and promoted the expression of different anti-inflammatory factors (CD206, TGF-β, IL-10 and IL-4) at different time points. Furthermore, NM could inhibit the expression of proinflammatory mediators and promote anti-inflammatory mediators expression in rat primary microglia following exposure to thrombin combined with oxygen-glucose deprivation (OGD). The immune-modulatory effect of NM might be partly due to its inhibition of the NF-κB signaling pathway and inflammasome activation after tMCAO. In addition, NM significantly inhibited the infiltration of macrophage, neutrophil and T lymphocytes, which was partly mediated by the inhibition of monocyte chemotactic protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). Taken together, our results indicated that NM can provide long-term protection of the brain against tMCAO by modulating a broad components of the inflammatory response.

Reexamining the Efficacy and Value of Percutaneous Coronary Intervention for Patients With Stable Ischemic Heart Disease

Percutaneous coronary intervention (PCI) continues to be performed frequently for patients with stable ischemic heart disease, despite uncertain efficacy. Individual randomized trial data and meta-analyses have not demonstrated that PCI in addition to optimal medical therapy reduces the incidence of death or myocardial infarction in patients with stable disease. The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) Trial did not show benefit for cardiovascular outcomes or mortality but did find a modest improvement in quality of life that did not persist at 3 years. Long-term follow-up from COURAGE (up to 15 years) found no differences in mortality, consistent with other published literature. How PCI could reduce long-term mortality or prevent myocardial infarction is not clear because sites of future plaque rupture leading to myocardial infarction are unpredictable and PCI can only treat localized anatomic segments of obstructive atherosclerosis. In addition, PCI is expensive, and the value to society of PCI for stable disease has not been demonstrated. The ISCHEMIA trial will assess the role of PCI for stable ischemic heart disease using newer technology and in patients with greater ischemic burden than in COURAGE. After nearly a decade, the COURAGE trial and other studies have given us pause to critically reexamine the role of PCI for patients with stable ischemic heart disease. Until further research can show that PCI can reduce cardiovascular events in these patients, a first-line strategy of optimal medical therapy is known to be safe, effective, and noninferior to PCI, and our practice should more closely follow this strategy.

Body size measures, hemostatic and inflammatory markers and risk of venous thrombosis: The Longitudinal Investigation of Thromboembolism Etiology

OBJECTIVE

Obesity is an important venous thrombosis (VT) risk factor but the reasons for this are unclear.

MATERIALS AND METHODS

In a cohort of 20,914 individuals aged 45 and older without prior VT, we calculated the relative risk (RR) of VT over 12.6years follow-up according to baseline body size measures, and studied whether associations were mediated by biomarkers of hemostasis and inflammation that are related to adiposity.

RESULTS

Greater levels of all body size measures (weight, height, waist, hip circumference, calf circumference, body-mass index, waist-hip ratio, fat mass and fat-free mass) were associated with increased risk of VT, with 4th versus 1st quartile RRs of 1.5-3.0. There were no multiplicative interactions of biomarkers with obesity status. Adjustment for biomarkers associated with VT risk and body size (factors VII and VIII, von Willebrand factor, partial thromboplastin time, D-dimer, C-reactive protein and factor XI) only marginally lowered, or did not impact, the RRs associated with body size measures.

CONCLUSIONS

Greater body size, by multiple measures, is a risk factor for VT. Associations were not mediated by circulating levels of studied biomarkers suggesting that body size relates to VT because of physical factors associated with blood flow, not the hypercoagulability or inflammation associated with adiposity.

Neuropsychological Assessment of Driving Capacity

Clinicians are increasingly requested to make determinations regarding patients' driving capacity in the context of neurological injury/conditions and a growing cohort of older drivers. The capability to drive safely involves a number of cognitive, physical, and sensorimotor abilities that may be impacted by injury, illness, or substances that influence alertness. Neuropsychological measures are an important component of a multidisciplinary approach for evaluation of driving capacity. Clinicians should become familiar with measures that have the best predictive validity so they may incorporate a patient's neurocognitive strengths and weaknesses in decisions about driving ability.

The Role of AGE/RAGE Signaling in Diabetes-Mediated Vascular Calcification

AGE/RAGE signaling has been a well-studied cascade in many different disease states, particularly diabetes. Due to the complex nature of the receptor and multiple intersecting pathways, the AGE/RAGE signaling mechanism is still not well understood. The purpose of this review is to highlight key areas of AGE/RAGE mediated vascular calcification as a complication of diabetes. AGE/RAGE signaling heavily influences both cellular and systemic responses to increase bone matrix proteins through PKC, p38 MAPK, fetuin-A, TGF-β, NFκB, and ERK1/2 signaling pathways in both hyperglycemic and calcification conditions. AGE/RAGE signaling has been shown to increase oxidative stress to promote diabetes-mediated vascular calcification through activation of Nox-1 and decreased expression of SOD-1. AGE/RAGE signaling in diabetes-mediated vascular calcification was also attributed to increased oxidative stress resulting in the phenotypic switch of VSMCs to osteoblast-like cells in AGEs-induced calcification. Researchers found that pharmacological agents and certain antioxidants decreased the level of calcium deposition in AGEs-induced diabetes-mediated vascular calcification. By understanding the role the AGE/RAGE signaling cascade plays diabetes-mediated vascular calcification will allow for pharmacological intervention to decrease the severity of this diabetic complication.

Proposed pathophysiologic framework to explain some excess cardiovascular death associated with ambient air particle pollution: Insights for public health translation

The paper proposes a pathophysiologic framework to explain the well-established epidemiological association between exposure to ambient air particle pollution and premature cardiovascular mortality, and offers insights into public health solutions that extend beyond regulatory environmental protections to actions that can be taken by individuals, public health officials, healthcare professionals, city and regional planners, local and state governmental officials and all those who possess the capacity to improve cardiovascular health within the population. The foundation of the framework rests on the contribution of traditional cardiovascular risk factors acting alone and in concert with long-term exposures to air pollutants to create a conditional susceptibility for clinical vascular events, such as myocardial ischemia and infarction; stroke and lethal ventricular arrhythmias. The conceptual framework focuses on the fact that short-term exposures to ambient air particulate matter (PM) are associated with vascular thrombosis (acute coronary syndrome, stroke, deep venous thrombosis, and pulmonary embolism) and electrical dysfunction (ventricular arrhythmia); and that individuals having prevalent heart disease are at greatest risk. Moreover, exposure is concomitant with changes in autonomic nervous system balance, systemic inflammation, and prothrombotic/anti-thrombotic and profibrinolytic-antifibrinolytic balance. Thus, a comprehensive solution to the problem of premature mortality triggered by air pollutant exposure will require compliance with regulations to control ambient air particle pollution levels, minimize exposures to air pollutants, as well as a concerted effort to decrease the number of people at-risk for serious clinical cardiovascular events triggered by air pollutant exposure by improving the overall state of cardiovascular health in the population. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu.

Nanoparticle-Mediated Delivery of Mitochondrial Division Inhibitor 1 to the Myocardium Protects the Heart From Ischemia-Reperfusion Injury Through Inhibition of Mitochondria Outer Membrane Permeabilization: A New Therapeutic Modality for Acute Myocardial Infarction

BACKGROUND

Mitochondria-mediated cell death plays a critical role in myocardial ischemia-reperfusion (IR) injury. We hypothesized that nanoparticle-mediated drug delivery of mitochondrial division inhibitor 1 (Mdivi1) protects hearts from IR injury through inhibition of mitochondria outer membrane permeabilization (MOMP), which causes mitochondrial-mediated cell death.

METHODS AND RESULTS

We formulated poly (lactic-co-glycolic acid) nanoparticles containing Mdivi1 (Mdivi1-NP). We recently demonstrated that these nanoparticles could be successfully delivered to the cytosol and mitochondria of cardiomyocytes under H2O2-induced oxidative stress that mimicked IR injury. Pretreatment with Mdivi1-NP ameliorated H2O2-induced cell death in rat neonatal cardiomyocytes more potently than Mdivi1 alone, as indicated by a lower estimated half-maximal effective concentration and greater maximal effect on cell survival. Mdivi1-NP treatment of Langendorff-perfused mouse hearts through the coronary arteries at the time of reperfusion reduced infarct size after IR injury more effectively than Mdivi1 alone. Mdivi1-NP treatment also inhibited Drp1-mediated Bax translocation to the mitochondria and subsequent cytochrome c leakage into the cytosol, namely, MOMP, in mouse IR hearts. MOMP inhibition was also observed in cyclophilin D knockout (CypD-KO) mice, which lack the mitochondrial permeability transition pore (MPTP) opening. Intravenous Mdivi1-NP treatment in vivo at the time of reperfusion reduced IR injury in wild-type and CypD-KO mice, but not Bax-KO mice.

CONCLUSIONS

Mdivi1-NP treatment reduced IR injury through inhibition of MOMP, even in the absence of a CypD/MPTP opening. Thus, nanoparticle-mediated drug delivery of Mdivi1 may be a novel treatment strategy for IR injury.

Platelets are versatile cells: New discoveries in hemostasis, thrombosis, immune responses, tumor metastasis and beyond

Platelets are small anucleate blood cells generated from megakaryocytes in the bone marrow and cleared in the reticuloendothelial system. At the site of vascular injury, platelet adhesion, activation and aggregation constitute the first wave of hemostasis. Blood coagulation, which is initiated by the intrinsic or extrinsic coagulation cascades, is the second wave of hemostasis. Activated platelets can also provide negatively-charged surfaces that harbor coagulation factors and markedly potentiate cell-based thrombin generation. Recently, deposition of plasma fibronectin, and likely other plasma proteins, onto the injured vessel wall has been identified as a new "protein wave of hemostasis" that may occur even earlier than the first wave of hemostasis, platelet accumulation. Although no experimental evidence currently exists, it is conceivable that platelets may also contribute to this protein wave of hemostasis by releasing their granule fibronectin and other proteins that may facilitate fibronectin self- and non-self-assembly on the vessel wall. Thus, platelets may contribute to all three waves of hemostasis and are central players in this critical physiological process to prevent bleeding. Low platelet counts in blood caused by enhanced platelet clearance and/or impaired platelet production are usually associated with hemorrhage. Auto- and allo-immune thrombocytopenias such as idiopathic thrombocytopenic purpura and fetal and neonatal alloimmune thrombocytopenia may cause life-threatening bleeding such as intracranial hemorrhage. When triggered under pathological conditions such as rupture of an atherosclerotic plaque, excessive platelet activation and aggregation may result in thrombosis and vessel occlusion. This may lead to myocardial infarction or ischemic stroke, the major causes of mortality and morbidity worldwide. Platelets are also involved in deep vein thrombosis and thromboembolism, another leading cause of mortality. Although fibrinogen has been documented for more than half a century as essential for platelet aggregation, recent studies demonstrated that fibrinogen-independent platelet aggregation occurs in both gene deficient animals and human patients under physiological and pathological conditions (non-anti-coagulated blood). This indicates that other unidentified platelet ligands may play important roles in thrombosis and might be novel antithrombotic targets. In addition to their critical roles in hemostasis and thrombosis, emerging evidence indicates that platelets are versatile cells involved in many other pathophysiological processes such as innate and adaptive immune responses, atherosclerosis, angiogenesis, lymphatic vessel development, liver regeneration and tumor metastasis. This review summarizes the current knowledge of platelet biology, highlights recent advances in the understanding of platelet production and clearance, molecular and cellular events of thrombosis and hemostasis, and introduces the emerging roles of platelets in the immune system, vascular biology and tumorigenesis. The clinical implications of these basic science and translational research findings will also be discussed.