Neutrophils as potential participants in acute myocardial ischemia: relevance to reperfusion

Ticagrelor vs. clopidogrel for coronary microvascular dysfunction in patients with STEMI: a meta-analysis of randomized controlled trials

Purpose

Approximately half of ST-segment elevation myocardial infarction (STEMI) patients who undergo revascularization present with coronary microvascular dysfunction. Dual antiplatelet therapy, consisting of aspirin and a P2Y12 inhibitor (e.g., clopidogrel or ticagrelor), is recommended to reduce rates of cardiovascular events after STEMI. The present study performed a pooled analysis of randomized controlled trials (RCTs) to compare effects of ticagrelor and clopidogrel on coronary microcirculation dysfunction in STEMI patients who underwent the primary percutaneous coronary intervention.

Methods

The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for eligible RCTs up to September 2022, with no language restriction. Coronary microcirculation indicators included the corrected thrombolysis in myocardial infarction (TIMI) frame count (cTFC), myocardial blush grade (MBG), TIMI myocardial perfusion grade (TMPG), coronary flow reserve (CFR), and index of microcirculatory resistance (IMR).

Results

Seven RCTs that included a total of 957 patients (476 who were treated with ticagrelor and 481 who were treated with clopidogrel) were included. Compared with clopidogrel, ticagrelor better accelerated microcirculation blood flow [cTFC = -2.40, 95% confidence interval (CI): -3.38 to -1.41, p < 0.001] and improved myocardial perfusion [MBG = 3, odds ratio (OR) = 1.99, 95% CI: 1.35 to 2.93, p < 0.001; MBG ≥ 2, OR = 2.57, 95% CI: 1.61 to 4.12, p < 0.001].

Conclusions

Ticagrelor has more benefits for coronary microcirculation than clopidogrel in STEMI patients who undergo the primary percutaneous coronary intervention. However, recommendations for which P2Y12 receptor inhibitor should be used in STEMI patients should be provided according to results of studies that investigate clinical outcomes.

Development and Validation of a Clinical and Laboratory-Based Nomogram for Predicting Coronary Microvascular Obstruction in NSTEMI Patients After Primary PCI

Objective

Cardiac microvascular obstruction (CMVO) remains a severe complication in non-ST elevation myocardial infarction (NSTEMI) patients with reperfusion therapy. We aimed at developing and validating the nomogram to predict the possibility of CMVO after primary percutaneous coronary intervention (PCI) by integrating clinical and laboratory-based information.

Methods

A total of 325 patients undergoing primary PCI for NSTEMI were recruited and divided into the training cohort (n=226) and the validating cohort (n = 99). The development of the nomogram was based on independent predictors of CMVO, and these variables were selected by multivariable logistic regression analysis.

Results

Independent predictors contained in nomogram were identified by multivariable logistic regression analysis, and these independent predictors included neutrophils (OR 1.166, 95% CI 1.044–1.303, P<0.01), hemoglobin (OR 1.037, 95% CI 1.013–1.062, P<0.01), triglyceride (OR 1.343, 95% CI 1.059; 1.704, P=0.015), Killip grade (OR 2.190, 95% CI 1.065–4.503, P=0.033), high thrombus load (OR 3.146, 95% CI 1.424–6.952, P<0.01), no-reflow (OR 3.142, 95% CI 1.419–6.955, P<0.01) and ischemic postconditioning (OR 0.445, 95% CI 0.209–0.944, P=0.035). The nomogram accurately predicted the presentation of CMVO in both the training set and validating set (AUC, 0.835 and 0.881, respectively). The results predicted by nomogram were confirmed to be highly consistent with the results of DE-CMR, both the training and validating cohorts, by Calibration plot and Hosmer-Lemeshow test. Decision curve analysis (DCA) also suggested that the nomogram was applicable in the clinic.

Conclusion

The nomogram showed good performance in predicting CMVO, and it could help clinicians optimize the clinical treatments to improve the prognosis of NSTEMI patients.

Coronary microvascular injury in myocardial infarction: perception and knowledge for mitochondrial quality control

Endothelial cells (ECs) constitute the innermost layer in all blood vessels to maintain the structural integrity and microcirculation function for coronary microvasculature. Impaired endothelial function is demonstrated in various cardiovascular diseases including myocardial infarction (MI), which is featured by reduced myocardial blood flow as a result of epicardial coronary obstruction, thrombogenesis, and inflammation. In this context, understanding the cellular and molecular mechanisms governing the function of coronary ECs is essential for the early diagnosis and optimal treatment of MI. Although ECs contain relatively fewer mitochondria compared with cardiomyocytes, they function as key sensors of environmental and cellular stress, in the regulation of EC viability, structural integrity and function. Mitochondrial quality control (MQC) machineries respond to a broad array of stress stimuli to regulate fission, fusion, mitophagy and biogenesis in mitochondria. Impaired MQC is a cardinal feature of EC injury and dysfunction. Hence, medications modulating MQC mechanisms are considered as promising novel therapeutic options in MI. Here in this review, we provide updated insights into the key role of MQC mechanisms in coronary ECs and microvascular dysfunction in MI. We also discussed the option of MQC as a novel therapeutic target to delay, reverse or repair coronary microvascular damage in MI. Contemporary available MQC-targeted therapies with potential clinical benefits to alleviate coronary microvascular injury during MI are also summarized.

Cerebral blood flow decrease as an early pathological mechanism in Alzheimer's disease

Therapies targeting late events in Alzheimer's disease (AD), including aggregation of amyloid beta (Aβ) and hyperphosphorylated tau, have largely failed, probably because they are given after significant neuronal damage has occurred. Biomarkers suggest that the earliest event in AD is a decrease of cerebral blood flow (CBF). This is caused by constriction of capillaries by contractile pericytes, probably evoked by oligomeric Aβ. CBF is also reduced by neutrophil trapping in capillaries and clot formation, perhaps secondary to the capillary constriction. The fall in CBF potentiates neurodegeneration by upregulating the BACE1 enzyme that makes Aβ and by promoting tau hyperphosphorylation. Surprisingly, therefore, CBF reduction may play a crucial role in driving cognitive decline by initiating the amyloid cascade itself, or being caused by and amplifying Aβ production. Here, we review developments in this area that are neglected in current approaches to AD, with the aim of promoting novel mechanism-based therapeutic approaches.

Effect of Platelet GPIIb/IIIa Receptor Blockade With MK383 on Infarct Size and Myocardial Blood Flow in a Canine Reocclusion Model

Platelet activation and aggregation during ischemia influence reperfusion-related myocyte necrosis, myocardial perfusion at the microvascular level, and thereby eventual recovery of cardiac performance. Inhibition of platelet activity therefore represents a worthwhile target to reduce cellular injury. The current study examined the effects of MK383 (tirofiban), a potent inhibitor of platelet aggregation, on infarct size and myocardial perfusion in canine subjects to either reocclusion (ie, 120-minute + 60-minute ischemia with intervening reperfusion) or prolonged occlusion (ie, 3 hours) followed by reperfusion (180 minutes). Platelet aggregation, infarct size (tetrazolium staining), coronary blood flow (flow probe), coronary vascular reserve, and myocardial perfusion (microspheres) were evaluated. MK383, administered at the time of reperfusion, produced a modest reduction of tissue necrosis (compared to saline-treated controls) in the reocclusion and prolonged occlusion studies. Blood flow in the infarct-related artery after coronary occlusion was comparable between treatment groups, as was myocardial perfusion in the deeper layers of the ischemic region; coronary vascular reserve decreased progressively during reperfusion. Of note, compensatory changes in blood flow within the adjacent nonischemic myocardium were not observed. In conclusion, we report that that limiting platelet aggregation during reperfusion impacted infarct development. Continued investigation into the mechanisms by which inhibition of platelet activity protects myocardium against ischemia-reperfusion injury and improves clinical outcomes is necessary.

PPARδ, a Potential Therapeutic Target for Heart Disease

The nuclear receptor peroxisome proliferator-activated receptor δ (PPARδ) can transcriptionally regulate target genes. PPARδ exerts essential regulatory functions in the heart, which requires constant energy supply. PPARδ plays a key role in energy metabolism, controlling not only fatty acid (FA) and glucose oxidation, but also redox homeostasis, mitochondrial biogenesis, inflammation, and cardiomyocyte proliferation. PPARδ signaling is impaired in the heart under various pathological conditions, such as pathological cardiac hypertrophy, myocardial ischemia/reperfusion, doxorubicin cardiotoxicity and diabetic cardiomyopathy. PPARδ deficiency in the heart leads to cardiac dysfunction, myocardial lipid accumulation, cardiac hypertrophy/remodeling and heart failure. This article provides an up-today overview of this research area and discusses the role of PPARδ in the heart in light of the complex mechanisms of its transcriptional regulation and its potential as a translatable therapeutic target for the treatment of cardiac disorders.

Role of S-methylisothiourea (SMT) in renal ischemia/reperfusion injury in rats

Introduction: Excessive production of nitric oxide (NO) via inducible nitric oxide synthase (iNOS) is associated in renal ischemia reperfusion injury (IRI).

Objectives: This study was designed to investigate the role of S-methylisothiourea (SMT) as selective inhibitor iNOS in renal IRI. Materials and Methods: Male Wistar rats were subjected to 45 minutes of bilateral renal ischemia by occlusion of renal vessels of both kidney followed by 24 hours of reperfusion. Prior to renal IRI, the rats received either vehicle (saline, group 2) or SMT (50 mg/kg, group 3), and were compared with the sham-operated animals (group 1). At the end of reperfusion period, the rats were sacrificed for kidney tissue pathology investigation.

Results: Serum creatinine (Cr), blood urea nitrogen (BUN), nitrite levels, and kidney weight significantly increased in groups 2 and 3 (P < 0.05). Kidney tissue damage scores in groups 2 and 3 were also higher than that in the sham-operated group (P < 0.05).

Conclusion: SMT not only prevent the kidney during IRI, but also promotes kidney function disturbance and severity of renal injury.

Inhibition of Platelet GPVI Protects Against Myocardial Ischemia-Reperfusion Injury

OBJECTIVE

The objective of this study was to investigate the effects of platelet inhibition on myocardial ischemia-reperfusion (IR) injury.

APPROACH AND RESULTS

Timely restoration of coronary blood flow after myocardial infarction is indispensable but leads to additional damage to the heart (myocardial IR injury). Microvascular dysfunction contributes to myocardial IR injury. We hypothesized that platelet activation during IR determines microvascular perfusion and thereby the infarct size in the reperfused myocardium. The 3 phases of thrombus formation were analyzed by targeting individual key platelet-surface molecules with monoclonal antibody derivatives: (1) adhesion (anti-glycoprotein [GP]-Ib), (2) activation (anti-GPVI), and (3) aggregation (anti-GPIIbIIIa) in a murine in vivo model of left coronary artery ligation (30 minutes of ischemia followed by 24 hours of reperfusion). Infarct sizes were determined by Evans Blue/2,3,5-triphenyltetrazolium chloride staining, infiltrating neutrophils by immunohistology. Anti-GPVI treatment significantly reduced infarct size versus control, whereas anti-GPIb or anti-GPIIbIIIa antibody fragments showed no significant differences. Mechanistically, anti-GPVI antibody-mediated reduction of infarct size was not because of impaired Ca(2+) signaling or platelet degranulation because mice deficient in store-operated calcium channels (stromal interaction molecule 1, ORAI1), α-granules (Nbeal2(-/-)), and dense granule release (Unc13d(-/-)) had similar infarct sizes as control animals. Protective effects of anti-GPVI treatment were accompanied by improved microperfusion. Leukocyte infiltration was reduced in both anti-GPVI and anti-GPIb-treated IR mice.

CONCLUSIONS

Inhibition of platelet activation by an anti-GPVI antibody, but not inhibition of platelet adhesion or aggregation by an anti-GPIb or anti-GPIIbIIIa antibody significantly reduces infarct size. The reduction of the infarct size is primarily based on an improved microperfusion after anti-GPVI antibody treatment.

Correlation of cystatin C and creatinine based estimates of renal function in children with hydronephrosis

INTRODUCTION

The use of a simple and accurate glomerular filtration rate (GFR) estimating method aiming minute assessment of renal function can be of great clinical importance.

OBJECTIVES

This study aimed to determine the association of a GFR estimating by equation that includes only cystatin C (Gentian equation) to equation that include only creatinine (Schwartz equation) among children.

PATIENTS AND METHODS

A total of 31 children aged from 1 day to 5 years with the final diagnosis of unilateral or bilateral hydronephrosis referred to Besat hospital in Hamadan, between March 2010 and February 2011 were consecutively enrolled. Schwartz and Gentian equations were employed to determine GFR based on plasma creatinine and cystatin C levels, respectively.

RESULTS

The proportion of GFR based on Schwartz equation was 70.19± 24.86 ml/min/1.73 m(2), while the level of this parameter based on Gentian method and using cystatin C was 86.97 ± 21.57 ml/min/1.73 m(2). The Pearson correlation coefficient analysis showed a strong direct association between the two levels of GFR measured by Schwartz equation based on serum creatinine level and Gentian method and using cystatin C (r = 0.594, P < 0.001). The linear association between GFR values measured with the two methods included cystatin C based GFR = 50.8+ 0.515 × Schwartz GFR. The correlation between GFR values measured by using serum creatinine and serum cystatin C measurements remained meaningful even after adjustment for patients' gender and age (r = 0.724, P < 0.001).

CONCLUSION

The equation developed based on cystatin C level is comparable with another equation, based on serum creatinine (Schwartz formula) to estimate GFR in children.

Improving Cell Engraftment in Cardiac Stem Cell Therapy

Myocardial infarction (MI) affects millions of people worldwide. MI causes massive cardiac cell death and heart function decrease. However, heart tissue cannot effectively regenerate by itself. While stem cell therapy has been considered an effective approach for regeneration, the efficacy of cardiac stem cell therapy remains low due to inferior cell engraftment in the infarcted region. This is mainly a result of low cell retention in the tissue and poor cell survival under ischemic, immune rejection and inflammatory conditions. Various approaches have been explored to improve cell engraftment: increase of cell retention using biomaterials as cell carriers; augmentation of cell survival under ischemic conditions by preconditioning cells, genetic modification of cells, and controlled release of growth factors and oxygen; and enhancement of cell survival by protecting cells from excessive inflammation and immune surveillance. In this paper, we review current progress, advantages, disadvantages, and potential solutions of these approaches.

Platelet/lymphocyte ratio was associated with impaired myocardial perfusion and both in-hospital and long-term adverse outcome in patients with ST-segment elevation acute myocardial infarction undergoing primary coronary intervention

Introduction

Platelet/lymphocyte ratio (PLR) has been shown to be an inflammatory and thrombotic biomarker for coronary heart disease, but its prognostic value in ST-segment elevation myocardial infarction (STEMI) has not been fully investigated.

Aim

To investigate the relationship between PLR and no-reflow, along with the in-hospital and long-term outcomes in patients with STEMI.

Material and methods

In the present study, we included 304 consecutive patients suffering from STEMI who underwent primary percutaneous coronary intervention (p-PCI). Patients were stratified according to PLR tertiles based on the blood samples obtained in the emergency room upon admission. No-reflow after p-PCI was defined as a coronary thrombolysis in myocardial infarction (TIMI) flow grade ≤ 2 after vessel recanalization, or TIMI flow grade 3 together with a final myocardial blush grade (MBG) < 2.

Results

The mean follow-up period was 24 months (range: 22–26 months). The number of patients characterized with no-reflow was counted to depict increments throughout successive PLR tertiles (14% vs. 20% vs. 45%, p < 0.001). In-hospital major adverse cardiovascular events and death increased as the PLR increased (p < 0.001, p < 0.001). Long-term MACE and death also increased as the PLR increased (p < 0.001, p < 0.001). Multivariable logistic regression analysis revealed that PLR remained an independent predictor for both in-hospital (OR = 1.01, 95% CI: 1.00–1.01; p = 0.002) and major long-term (OR = 1.01, 95% CI: 1.00–1.01; p < 0.001) adverse cardiac events.

Conclusions

Platelet/lymphocyte ratio on admission is a strong and independent predictor of both the no-reflow phenomenon and long-term prognosis following p-PCI in patients with STEMI.

Neutrophil–Lymphocyte Ratio and Platelet–Lymphocyte Ratio Combination Can Predict Prognosis in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

We assessed the effect of combination of neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) in predicting in-hospital and long-term mortality in patients (n = 2518) undergoing primary percutaneous coronary intervention (pPCI). Cutoff values for NLR and PLR were calculated with receiver–operating characteristic (ROC) curves. If both PLR and NLR were above the threshold, patients were classified as “high risk.” If either PLR or NLR was above the threshold individually, patients were classified as “intermediate risk.” High-risk (n = 693) and intermediate-risk (n = 545) groups had higher in-hospital and long-term mortality (7.2 4% vs 0.7%, P < .001; 14.1, 9.5% vs 4.5%, P < .001, respectively). Classifying patients into intermediate-risk group (hazards ratio [HR]: 1.492, 95% confidence interval [CI]: 1.022-2.178, P = .038) and high-risk group (HR: 1.845, 95% CI: 1.313-2.594, P < .001) was an independent predictor of in-hospital and long-term mortality. The combination of PLR and NLR can be useful for the prediction of in-hospital and long-term mortality in patients undergoing pPCI.

Safety and feasibility of high-dose administration of nicorandil before reperfusion therapy in acute myocardial infarction

The efficacy and safety of high-dose nicorandil therapy in acute myocardial infarction (AMI) have not yet been clarified. This is a prospective study including 30 patients who received nicorandil at 0.06 mg/kg/h [standard dose nicorandil (SDN) group] and 32 patients who received a bolus injection of nicorandil 0.2 mg/kg followed by a continuous infusion at 0.2 mg/kg/h [high-dose nicorandil (HDN) group]. The benefits and adverse events were assessed during acute phase and 12-month follow-up period. There were no significant differences between the groups in blood pressure, heart rate or urine volume 2, 6 and 24 h after drug administration, although blood pressure decreased during acute phase. The percentages of patients who required dose reduction or discontinuation of nicorandil were 34.4 and 16.7 % in HDN and SDN groups, respectively (p = 0.11). In HDN group, subgroup analysis revealed that the TIMI frame count (TFC) was significantly lower in patients in whom the treatment was started within 12 h compared to those more than 12 h (17.0 vs. 21.0, p = 0.017) and in patients with baseline WBC elevation compared to those without it (16.5 vs. 22.0, p = 0.029). A TFC of >20 was significantly associated with being in HDN group [odds ratio (OR) 0.27; 95 % confidence interval, CI 0.07-0.89], onset-to-balloon time (OR 1.06; 95 % CI 1.01-1.16), and ∑creatine kinase (OR 7.27; 95 % CI 1.40-57.83). There were no significant differences in incidences of cardiovascular death, rehospitalization, and target lesion revascularization between the groups. HDN therapy may improve coronary microcirculation in patients with AMI.

Predictive value of elevated neutrophil to lymphocyte ratio in patients undergoing primary angioplasty for ST-segment elevation myocardial infarction

OBJECTIVES

The neutrophil to lymphocyte ratio (NLR) has been investigated as a new predictor for cardiovascular risk. Admission NLR would be predictive of adverse outcomes after primary angioplasty for ST-segment elevation myocardial infarction (STEMI).

METHODS

A total of 2410 patients with STEMI undergoing primary angioplasty were retrospectively enrolled. The study population was divided into tertiles based on the NLR values. A high NLR (n = 803) was defined as a value in the third tertile (>6.97), and a low NLR (n = 1607) was defined as a value in the lower 2 tertiles (≤6.97).

RESULTS

High NLR group had higher incidence of inhospital and long-term cardiovascular mortality (5% vs 1.4%, P < .001; 7% vs 4.8%, P = .02, respectively). High NLR (>6.97) was found as an independent predictor of inhospital cardiovascular mortality (odds ratio: 2.8, 95% confidence interval: 1.37-5.74, P = .005).

CONCLUSIONS

High NLR level is associated with increased inhospital and long-term cardiovascular mortality in patients with STEMI undergoing primary angioplasty.

The long-term predictive value of the neutrophil-to-lymphocyte ratio in Type 2 diabetic patients presenting with acute myocardial infarction

BACKGROUND

Patients with diabetes mellitus have worse long-term outcomes after acute myocardial infarction (AMI) than non-diabetics. This may be related to differential contribution of neutrophil and lymphocyte to inflammation during AMI in diabetics vs. non-diabetics. We aim to determine the predictive value of neutrophil-to-lymphocyte ratio (NLR) for major adverse events post-AMI in Type 2 diabetics vs. non-diabetics.

METHODS AND RESULTS

A total of 2559 consecutive patients admitted for AMI (61 ± 14 years, 73% male and 43% diabetic) were analyzed. A complete blood count was obtained and the NLR computed for each patient on admission. Across the cohort, the 1-year reinfarction rate was 8.4% (n = 214) and 1-year mortality was 14.5% (n = 370). Univariate determinants of the composite endpoint included age, hypertension, hyperlipidemia, smoking, revascularization and NLR (P < 0.001 for all). The cohort was divided into NLR quartiles. Admission NLR was significantly higher in the diabetic group, 5.2 ± 5.8 vs. 4.6 ± 5.4 (P = 0.007). A step-wise increase in the incidence of the composite endpoint was noted across NLR quartiles for diabetic subjects; hazard ratio (HR) was 2.41 for fourth vs. first quartile (95% confidence interval = 1.63-3.53, P < 0.001). Multivariate analysis of the diabetic group showed that NLR remains as an independent predictor of the composite endpoint (adjusted HR = 1.53, 95% confidence interval = 1.00-2.33, P = 0.048). However, in non-diabetics, HR for NLR was not significant (P = 0.35).

CONCLUSION

Increased NLR post-AMI is an independent predictor of major adverse cardiac events in diabetics. Monitoring this easily obtainable new index allows prognostication and risk stratification.

Bimodal response to aspirin loading in acute ST-elevation myocardial infarction

Patients with stable coronary disease who exhibit platelet hypo-responsiveness to aspirin (ASA) have worse outcomes. Little data exist regarding platelet response to ASA in ST-elevation myocardial infarction (STEMI) patients. Our objective was to assess acute platelet response to ASA loading in STEMI patients undergoing primary percutaneous coronary intervention (PCI). The study comprised 102 consecutive patients with STEMI. All patients received a loading dose of 300 mg chewable ASA upon admission. Platelet reactivity was assessed immediately prior to primary PCI, at a median of 95(63 139) minutes after ASA loading. A bimodal response to arachidonic acid (AA) stimulation was observed, such that two distinct populations could be discerned: "good responders" had a mean AA-induced platelet aggregation of 36 ± 11% vs. 79 ± 9% for "poor responders." Despite equivalent demographic, clinical, and angiographic characteristics, good responders were significantly more likely to demonstrate early ST-segment resolution ≥70% after primary PCI (80% vs. 48%, p = 0.001), suggestive of better myocardial reperfusion. Early inhibition of AA-induced platelet aggregation post-ASA loading in the setting of STEMI is associated with better tissue reperfusion; however, a sizeable proportion of patients do not achieve significant inhibition of AA-induced platelet aggregation in response to ASA loading at the time of primary PCI.

Effect of Aspiration Thrombectomy on Microvascular Dysfunction in ST-Segment Elevation Myocardial Infarction With an Elevated Neutrophil Count

Background and Objectives

Aspiration thrombectomy (AT) during primary percutaneous coronary intervention (PCI) is an effective adjunctive therapy for ST-segment elevation myocardial infarction (STEMI). An elevated neutrophil count in STEMI is associated with microvascular dysfunction and adverse outcomes. We evaluated whether AT can improve microvascular dysfunction in patients with STEMI and an elevated neutrophil count.

Subjects and Methods

Seventy patients with STEMI undergoing primary PCI from August 2007 to February 2009 in our institution were classified by tertiles of neutrophil count on admission (<5,300/mm³, 5,300-7,600/mm³, and >7,600/mm³). The angiographic outcome was post-procedural thrombolysis in myocardial infarction (TIMI) flow grade. Microvascular dysfunction was assessed by TIMI myocardial perfusion (TMP) grade and ST-segment resolution on electrocardiography 90 minutes after PCI. The clinical outcome was major adverse cardiac event (MACE), defined as cardiac death, re-infarction, and target lesion revascularization at 9 months.

Results

There were no significant differences in the clinical characteristics and pre- and post-procedural TIMI flow grades between the neutrophil tertiles. As the neutrophil count increased, a lower tendency toward TMP grade 3 (83% vs. 52% vs. 54%, p=0.06) and more persistent residual ST-segment elevation (>4 mm: 13% vs. 26% vs. 58%, p=0.005) was observed. The 9-month MACE rate was similar between the groups. On subgroup analysis of AT patients (n=52) classified by neutrophil tertiles, the same tendency toward less frequent TMP grade 3 (77% vs. 56% vs. 47%, p=0.06) and persistent residual ST-segment elevation (>4 mm: 12% vs. 28% vs. 53%, p=0.05) was observed as neutrophil count increased.

Conclusion

A higher neutrophil count at presentation in STEMI is associated with more severe microvascular dysfunction after primary PCI, which is not improved with AT.

The paradox of the neutrophil's role in tissue injury

The neutrophil is an essential component of the innate immune system, and its function is vital to human life. Its production increases in response to virtually all forms of inflammation, and subsequently, it can accumulate in blood and tissue to varying degrees. Although its participation in the inflammatory response is often salutary by nature of its normal interaction with vascular endothelium and its capability to enter tissues and respond to chemotactic gradients and to phagocytize and kill microrganisms, it can contribute to processes that impair vascular integrity and blood flow. The mechanisms that the neutrophil uses to kill microorganisms also have the potential to injure normal tissue under special circumstances. Its paradoxical role in the pathophysiology of disease is particularly, but not exclusively, notable in seven circumstances: 1) diabetic retinopathy, 2) sickle cell disease, 3) TRALI, 4) ARDS, 5) renal microvasculopathy, 6) stroke, and 7) acute coronary artery syndrome. The activated neutrophil's capability to become adhesive to endothelium, to generate highly ROS, and to secrete proteases gives it the potential to induce local vascular and tissue injury. In this review, we summarize the evidence for its role as a mediator of tissue injury in these seven conditions, making it or its products potential therapeutic targets.

Treatment with the C5a receptor antagonist ADC-1004 reduces myocardial infarction in a porcine ischemia-reperfusion model

BACKGROUND

Polymorphonuclear neutrophils, stimulated by the activated complement factor C5a, have been implicated in cardiac ischemia/reperfusion injury. ADC-1004 is a competitive C5a receptor antagonist that has been shown to inhibit complement related neutrophil activation. ADC-1004 shields the neutrophils from C5a activation before they enter the reperfused area, which could be a mechanistic advantage compared to previous C5a directed reperfusion therapies. We investigated if treatment with ADC-1004, according to a clinically applicable protocol, would reduce infarct size and microvascular obstruction in a large animal myocardial infarct model.

METHODS

In anesthetized pigs (42-53 kg), a percutaneous coronary intervention balloon was inflated in the left anterior descending artery for 40 minutes, followed by 4 hours of reperfusion. Twenty minutes after balloon inflation the pigs were randomized to an intravenous bolus administration of ADC-1004 (175 mg, n = 8) or saline (9 mg/ml, n = 8). Area at risk (AAR) was evaluated by ex vivo SPECT. Infarct size and microvascular obstruction were evaluated by ex vivo MRI. The observers were blinded to the treatment at randomization and analysis.

RESULTS

ADC-1004 treatment reduced infarct size by 21% (ADC-1004: 58.3 ± 3.4 vs control: 74.1 ± 2.9%AAR, p = 0.007). Microvascular obstruction was similar between the groups (ADC-1004: 2.2 ± 1.2 vs control: 5.3 ± 2.5%AAR, p = 0.23). The mean plasma concentration of ADC-1004 was 83 ± 8 nM at sacrifice. There were no significant differences between the groups with respect to heart rate, mean arterial pressure, cardiac output and blood-gas data.

CONCLUSIONS

ADC-1004 treatment reduces myocardial ischemia-reperfusion injury and represents a novel treatment strategy of myocardial infarct with potential clinical applicability.

Predicting the no-reflow phenomenon following successful percutaneous coronary intervention

In the setting of acute myocardial infarction, early and adequate reopening of an infarct-related artery is not necessarily followed by a complete restoration of myocardial perfusion. This condition is usually defined as ‘no-reflow’. The pathophysiology of no-reflow is multifactorial since extravascular compression, microvascular vasoconstriction, embolization during percutaneous coronary intervention, and platelet and neutrophil aggregates are involved. In the clinical arena, angiographic findings and easily available clinical parameters can predict the risk of no-reflow. More recently, several studies have demonstrated that biomarkers, especially those related to the pathogenetic components of no-reflow, could also have a prognostic role in the prediction and in the full understanding of the multiple mechanisms of this phenomenon. Thus, in this article, we investigate the role of several biomarkers on admission in predicting the occurrence of no-reflow following successful percutaneous coronary intervention.

Neutrophil count on admission predicts major in-hospital events in patients with a non-ST-segment elevation acute coronary syndrome

BACKGROUND

Inflammation plays a key role in the pathogenesis of acute coronary syndromes (ACS). In this context we assessed neutrophil count as a predictor of major in-hospital events in patients admitted for a non-ST-segment elevation (NSTE) ACS.

METHODS

We measured neutrophils on admission in 160 patients with a NSTE ACS and we correlated their count with the incidence of a combined in-hospital end point including: cardiac death, acute heart failure, ST-segment elevation myocardial infarction, and recurrent myocardial ischemia.

RESULTS

Patients who had a major in-hospital event also had a higher neutrophil count (P = 0.02) and higher serum levels of troponin I (P = 0.04). In the univariate logistic regression analysis, in-hospital major events could be predicted by troponin I > 0.07 ng/mL (odds ratio [OR]: 5.65, 95% confidence interval [CI]: 1.26-25.32, P = 0.02), white blood cell count > 8650 cells/microL (OR: 2.68, 95% CI: 1.03-6.95, P = 0.04), neutrophil count > 6700 cells/microL (OR: 7.74, 95% CI: 2.79-21.47, P < 0.001), and C-reactive protein > 0.97 mg/dL (OR: 3.56, 95% CI: 1.13-11.19, P = 0.02). However, in multivariate regression, neutrophil count > 6700 cells/microL (OR: 6.52, 95% CI: 1.56-27.22, P = 0.01) was the only independent in-hospital prognostic factor.

CONCLUSIONS

In patients with a NSTE ACS of moderate or high risk, neutrophil count on admission may identify those who are at risk of having an adverse in-hospital outcome.

The appearance of L-selectin(low) polymorphonuclear leukocytes in the circulating pool of peripheral blood during myocardial infarction correlates with neutrophilia and with the size of the infarct

BACKGROUND

It is assumed that not only leukocytosis, but also the activation of white blood cells (WBC) may play a role in the pathogenesis and prognosis of patients with myocardial infarction (MI). Activation of WBC includes upregulation of CD11b/CD18 and downregulation of CD62L (L-selectin) antigens.

HYPOTHESIS

The activation of WBC is associated with the appearance of a larger MI.

METHODS

CD11b/CD18 and CD62L were measured on the surface of WBC on Day 1 and Day 3 from the onset of MI. The size of the infarct with estimated by calculating the area under the curve of the creatine kinase enzyme, which was measured every 6 h.

RESULTS

A negative correlation was noted between the absolute polymorphonuclear count and the availability of the CD62L on these cells during Day 1 (r = -0.46, p = 0.003) and Day 3 (r = -0.35, p = 0.05). There was a positive correlation between the size of MI and the WBC count (r = 0.46, p = 0.004) and a negative correlation with CD62L on polymorphonuclears (r = -0.35, p = 0.03). During Day 3, the CD11b/CD18 on the polymorphonuclears increased despite a decrement in the absolute number of these cells.

CONCLUSION

The neutrophilia during the early phases of acute MI correspond to the appearance of the L-selectin(low) population of polymorphonuclear leukocytes. There is a correlation between the appearance of this population and the size of the infarct.

Combined prognostic utility of white blood cell count, plasma glucose, and glomerular filtration rate in patients undergoing primary stent placement for acute myocardial infarction

Although high white blood cell (WBC) count and plasma glucose (PG) and low glomerular filtration rate (GFR) on admission have been associated with poor outcomes after acute myocardial infarction (AMI), the combined prognostic utility of these 3 variables was unclear. The association of WBC count, PG, and GFR on admission to in-hospital outcomes was examined in 2,633 patients who underwent primary stent placement for ST-segment elevation AMI within 48 hours after symptom onset. In-hospital mortality progressively increased as the number of the variables of high WBC count (> or =11,120/microl; upper tertile), high PG (> or =10.4 mmol/L; upper tertile), and low GFR (< or =60 ml/min/1.73 m(2); lower tertile) increased. Patients with all 3 variables had a strikingly higher in-hospital mortality rate (25.9%). After adjusting for baseline characteristics, multivariate analysis showed that compared with patients who had none of these variables, odds ratios for in-hospital mortality were 1.63 (95% confidence interval [CI] 0.88 to 3.03, p = 0.12) in patients with only 1 variable, 2.33 (95% CI 1.28 to 3.96, p = 0.047) in those with 2 variables, and 6.16 (95% CI 2.98 to 12.6, p <0.001) in those with all 3 variables. In conclusion, combined evaluation of WBC count, PG, and GFR on admission was a simple and useful method for the early prediction of risk of in-hospital death in patients undergoing primary stent placement for ST-segment elevation AMI.

Comparison of myocardial reperfusion in patients with fasting blood glucose < or =100, 101 to 125, and >125 mg/dl and ST-elevation myocardial infarction with percutaneous coronary intervention

Diabetes and impaired fasting glucose (FG) were associated with worse outcomes in patients with acute myocardial infarction (MI). Because the underlying mechanism is not entirely clear, 376 consecutive patients with ST-elevation MI who underwent primary percutaneous coronary intervention (PPCI) were investigated. Patients were divided into 3 groups based on FG < or =100, FG of 101 to 125, and FG >125 mg/dl or previously diagnosed diabetes mellitus (DM) and studied for electrocardiographic signs of myocardial reperfusion (both spontaneous and after PPCI) and clinical outcomes. Clinical reperfusion was less likely with increasing FG: FG < or =100 mg/dl, 26%; FG of 101 to 125, 19%; and FG >125 and/or DM, 16% (p for trend = 0.03). Accordingly, angiographic TIMI grade 3 flow on initial angiography was 22% for FG < or =100 mg/dl, 13% for FG of 101 to 125, and 14% for FG >125 and/or DM (p for trend = 0.05). Despite similar TIMI flow after PPCI, early ST-segment resolution (> or =70%) was noted in 76%, 63%, and 60% in patients with FG < or =100 mg/dl, FG of 101 to 125, and FG >125 and/or DM, respectively (p for trend <0.01). Peak creatine phosphokinase (CPK) increased gradually, whereas left ventricular ejection fraction decreased with increased FG. Worse outcomes were observed with increasingly higher FG for heart failure (9%, 23%, and 26%; p for trend <0.01), cardiogenic shock (5%, 7%, and 13%; p for trend = 0.02), in-hospital mortality (1%, 2%, and 6%; p for trend = 0.01), and long-term mortality (2.5%, 4.5%, and 12%; p for trend <0.01) for patients with FG < or =100 mg/dl, FG of 101 to 125, and FG >125 and/or DM, respectively. In conclusion, increased FG and previously diagnosed DM were associated with less spontaneous reperfusion and less myocardial reperfusion after PPCI, resulting in worse clinical outcomes.

Relationship of admission neutrophil count to microvascular injury, left ventricular dilation, and long-term outcome in patients treated with primary angioplasty for acute myocardial infarction

BACKGROUND

The relationship of admission neutrophil count to the degree of microvascular injury, left ventricular (LV) volume, and long-term outcome after acute myocardial infarction (AMI) was examined in the present study.

METHODS AND RESULTS

The study group comprised 228 consecutive patients with a first anterior wall AMI who underwent primary angioplasty within 12 h of onset. The degree of microvascular injury was evaluated by Doppler guidewire. Adverse cardiac events were recorded during an average follow-up of 52+/-28 months. Using a receiver-operating characteristic analysis, a neutrophil count >or=7,260 cells/mm(3) was the best predictor of future cardiac events. By regression analysis, the neutrophil count significantly correlated with diastolic deceleration time (r=-0.40, p<0.0001), coronary flow reserve (r=-0.43, p<0.0001), and LV end-diastolic volume at 4 weeks (r=0.32, p<0.0001). Kaplan-Meier survival analysis showed a higher incidence of adverse cardiac events in patients with a high neutrophil count (p=0.002). By multivariate analysis, a neutrophil count >or=7,260 cells/mm(3) was an independent predictor of long-term adverse cardiac events (odds ratio 3.8, p=0.002).

CONCLUSION

Neutrophilia on admission is associated with impaired microvascular perfusion, LV dilation, and long-term adverse cardiac events in patients treated with primary angioplasty for AMI.

Does absolute neutrophilia predict early congestive heart failure after acute myocardial infarction? A cross-sectional study

BACKGROUND

Acute myocardial infarction (AMI) is usually associated with increased neutrophil count. However, it has not clearly been defined whether neutrophilia can cause myocardial injury. In this study, we hypothesized that absolute neutrophilia can predict the occurrence of congestive heart failure (CHF) after AMI.

METHODS

A cross-sectional study was carried out on 312 patients with a diagnosis of AMI. Patients with a history of chest pain for more than 12 hours before admission, heart failure with Killip class III and IV, history of recent gastrointestinal bleeding, major trauma, infection, malignancy, renal failure and corticosteroid consumption were excluded. A blood sample was drawn for leukocyte count and an echocardiogram was obtained 4 days after admission. Congestive heart failure was defined as an ejection fraction less than 40% on echocardiogram or clinical heart failure according to the Framingham's criteria for diagnosis of heart failure.

RESULTS

After excluding 19 patients, data for 293 patients were analyzed. Among them, 152 (51.9%) patients developed new onset CHF. Two hundred and two patients (68.9%) had neutrophilia (neutrophil count >7500/mic/lit). The risk of developing heart failure was higher in patients with neutrophilia (OR = 2.32; 95% CI = 1.33-4.03, P = 0.000). There was a negative correlation between ejection fraction and neutrophil count (r = -0.191, P = 0.000). After adjustment for age, sex, serum creatinine level, peak enzyme CK-MB level and MI location, the relationship between the absolute neutrophil count and the presence of congestive heart failure remained significant (OR = 2.14; 95% CI = 1.19-3.84, P = 0.011).

CONCLUSIONS

The study shows that the presence of absolute neutrophilia during the first 12 hours after AMI can predict the occurrence of CHF. This association may help identify high-risk individuals, who might benefit from more aggressive interventions.

[Is morphine still the analgesic of choice in acute myocardial infarction?]

Chest pain is the most common symptom of patients who present with ischemic heart disease. Morphine has traditionally been the drug of choice for managing chest pain in acute coronary syndrome (ACS) due to its high analgesic potency, though its physiological effects are poorly understood. Routinely used for managing chest pain, morphine is recommended in the 2002 guidelines of the American College of Cardiology/American Heart Association. This recommendation, however, is not based on a high level of scientific evidence but on expert opinion. Studies have found both for and against the use of morphine in ACS, suggesting that its benefits are perhaps not altogether clear. This review examines the pathophysiological effects of morphine and their cardiac implications, with special attention to a possible negative effect on ACS. We reviewed articles in the MEDLINE database from 1982 to 2006.

Atherosclerosis pathophysiology and the role of novel risk factors: a clinicobiochemical perspective

Atherosclerosis is the root cause of the biggest killer of the 21st century. Mechanisms contributing to atherogenesis are multiple and complex. A number of theories-including the role of dyslipidemia, hypercoagulability, oxidative stress, endothelial dysfunction, and inflammation and infection by certain pathogens-have been propounded from time to time explain this complex phenomenon. Recently it has been suggested that atherosclerosis is a multifactorial, multistep disease that involves chronic inflammation at every step, from initiation to progression, and that all the risk factors contribute to pathogenesis by aggravating the underlying inflammatory process. A better understanding of the pathogenesis of atherosclerosis will aid in devising pharmaceutical and lifestyle modifications for reducing mortality resulting from coronary artery disease (CAD).A comprehensive literature search was conducted using the Web sites of the National Library of Medicine (http:// www.ncbl.nlm.nih.gov/) and PubMed Central, the US National Library of Medicine's digital archive of life sciences literature (http:// www.pubmedcentral.nih.gov/). The data were accessed from books and journals in which relevant articles in this field were published. The whole spectrum of coronary artery disease evolves through various events that lead to the formation and progression of atherosclerotic plaque and finally its complications. Atherosclerosis is the culprit behind coronary artery disease, cerebral vascular disease, and peripheral vascular disease. The pathogenic mechanisms are varied and complex. Of late, the role of lipoprotein (a), homocysteine, and inflammation and infection as prime culprits in pathogenesis of CAD is the subject of intense research and debate. The appreciation of the role of inflammation in atherosclerosis provides a mechanistic framework to understand the clinical benefits of newer therapeutic strategies, and a better understanding of pathogenesis aids in formulating preventive and therapeutic strategies in reducing mortality resulting from CAD.An in-depth knowledge of the various pathogenic mechanisms involved in atherosclerosis can help in substantiating the current existing knowledge about the CAD epidemic. This knowledge will help clinicians to better manage the disease, which affects Indians in its most severe form.

Role of oxygen in postischemic myocardial injury

Myocardial function is dependent on a constant supply of oxygen from the coronary circulation. A reduction of oxygen supply due to coronary obstruction results in myocardial ischemia, which leads to cardiac dysfunction. Reperfusion of the ischemic myocardium is required for tissue survival. Thrombolytic therapy, coronary artery bypass surgery and coronary angioplasty are some of the treatments available for the restoration of blood flow to the ischemic myocardium. However, the restoration of blood flow may also lead to reperfusion injury, resulting in myocyte death. Thus, any imbalance between oxygen supply and metabolic demand leads to functional, metabolic, morphologic, and electrophysiologic alterations, causing cell death. Myocardial ischemia reperfusion (IR) injury is a multifactorial process that is mediated by oxygen free radicals, neutrophil activation and infiltration, calcium overload, and apoptosis. Controlled reperfusion of the ischemic myocardium has been advocated to prevent the IR injury. Studies have shown that reperfusion injury and postischemic cardiac function are related to the quantity and delivery of oxygen during reperfusion. Substantial evidence suggests that controlled reoxygenation may ameliorate postischemic organ dysfunction. In this review, we discuss the role of oxygenation during reperfusion and subsequent biochemical and pathologic alterations in reperfused myocardium and recovery of heart function.

Neutrophil elastase gene variation and coronary heart disease

AIMS

Identification and functional characterization of variants in the neutrophil elastase (ELA2) gene in cardiovascular disease.

METHODS

From participants of the ECTIM (Etude Cas-Témoins sur l'infarctus du Myocarde) Study with myocardial infarction (MI) 2082 chromosomes were genetically scanned; 990 patients with MI and 904 controls were genotyped for the common polymorphisms G-761A and S173S (C4890A). Expression vectors for Ela2 variants were transiently transfected, followed by Northern and Western blot analyses. Promoter variants were analyzed by transfection/reporter gene assays.

RESULTS

We identified 11 genetic variants, two in the 5'-flanking (G-761A, -852/del53 bp), six in exons (R49H, N81N, G93V, S173S, D222Y, P228L) and three in introns (C+29/in3T, C+149/in3T, C+137/in4T). In Belfast, 4890A allele carriers had a risk for MI with an odds ratio (OR) of 1.44 (95% CI 1.12-1.86; P=0.005), the OR for MI associated with the -761G/-4890A haplotype with reference to -761G/-4890C amounting to 2.38 (95% CI 1.23-4.57; P=0.01). Transcript or protein expression of both allelic constructs (4890A and 4890C) did not, however, differ. Conversely, transcriptional activity was significantly elevated (<35%) by -852/del53 bp in THP-1 monocytes compared with the nondeleted promoter (P=0.001); the deletion was observed in one patient with premature MI at the age of 28 years, whose mother had had an MI at the age of 48 years.

CONCLUSIONS

The association of C4890A with MI in Belfast exclusively, and the presumed absence of its functionality, provides little support for a substantial implication of common ELA2 gene variants in overall MI risk. Whether -852/53del plays a role in cardiovascular pathophysiology or not should be evaluated further.

Relation between neutrophil counts on admission, microvascular injury, and left ventricular functional recovery in patients with an anterior wall first acute myocardial infarction treated with primary coronary angioplasty

Increased neutrophil counts have been associated with an increased risk of adverse clinical events after acute myocardial infarction (AMI). We examined the association of neutrophil counts on admission with degree of microvascular injury and left ventricular functional recovery after primary coronary angioplasty in AMI. We studied 116 patients with a first anterior wall AMI who underwent primary coronary angioplasty within 12 hours of onset. Patients were categorized into 3 groups based on initial neutrophil count: low (<5,000/mm(3)), intermediate (5,000 to 10,000/mm(3)), and high (>10,000/mm(3)). Coronary flow velocity parameters were assessed immediately after reperfusion using a Doppler guidewire. We defined severe microvascular injury as the presence of systolic flow reversal and a diastolic deceleration time <600 ms. Echocardiographic wall motion was analyzed before revascularization and 4 weeks after revascularization. In patients with a high neutrophil count, systolic flow reversal was more frequently observed, diastolic deceleration time was shorter, and coronary flow reserve was lower. By regression analysis, neutrophil count significantly correlated with diastolic deceleration time (r = -0.38, p <0.0001), coronary flow reserve (r = -0.33, p = 0.0004), and score for change in wall motion (r = -0.36, p = 0.0004). Multivariate analysis showed that neutrophil count on admission was an independent predictor of severe microvascular injury (odds ratio 2.94, p = 0.02). In conclusion, neutrophilia on admission is associated with impaired microvascular reperfusion and poor functional recovery after primary coronary angioplasty.

Association of haematological indices with the degree of microvascular injury in patients with acute anterior wall myocardial infarction treated with primary percutaneous coronary intervention

BACKGROUND

In acute myocardial infarction (AMI), increased neutrophil count has been associated with more severe coronary artery disease and larger infarct size. Increased mean platelet volume (MPV) is also associated with poor clinical outcome and impaired angiographic reperfusion in patients with AMI. However, the associations of neutrophil count and MPV with the indices of tissue level reperfusion were not fully elucidated.

AIM

To elucidate the relationship between baseline neutrophil count and MPV on presentation and microvascular injury in patients with anterior AMI treated with primary percutaneous coronary intervention (pPCI).

METHODS

41 patients with anterior wall AMI treated successfully with pPCI were included. The leucocyte count, neutrophil count and MPV were obtained on admission, and the percentage of neutrophils was calculated. After PCI thrombolysis in myocardial infarction, grade 3 flow was established in all patients. The coronary flow velocity pattern (diastolic deceleration time (DDT)) was examined with transthoracic echocardiography and measured intracoronary pressures with fibreoptic pressure-temperature sensor-tipped guidewire in the left anterior descending artery within 48 h after pPCI. Thermodilution-derived coronary flow reserve (CFR) was calculated. Index of microvascular resistance (IMR) was defined as simultaneously measured distal coronary pressure divided by the inverse of the thermodilution-derived hyperaemic mean transit time. Subsequently, a short compliant balloon was placed in the stented segment and inflated to measure coronary wedge pressure (CWP).

RESULTS

Higher neutrophil counts were strongly associated with higher IMR (r = 0.86, p<0.001), lower CFR (r = -0.60, p<0.001), shorter DDT (r = -0.73, p<0.001) and higher CWP (r = 0.73, p<0.001). Likewise, there were significant correlations among the percentage of neutrophils and CFR (r = -0.34, p = 0.02), IMR (r = 0.46, p = 0.002), DDT (r = -0.36, p = 0.01) and CWP (r = 0.49, p = 0.001). Relationships among leucocyte count and IMR (r = 0.38, p = 0.01), CFR (r = -0.33, p = 0.03), DDT (r = -0.36, p = 0.01) and CWP (r = 0.32, p = 0.026) were slightly significant. Higher neutrophil count remained independently associated with indices of microvascular perfusion in multivariable models controlling for age, smoking habits and time to treatment. Also, higher MPV on admission was strongly associated with higher IMR (r = 0.89, p<0.001), steeper DDT (r = -0.64, p<0.001), lower CFR (r = -0.43, p = 0.004) and higher CWP (r = 0.77, p<0.001).

CONCLUSION

Absolute and relative neutrophilia and higher MPV on admission were independently associated with impaired microvascular perfusion in patients with anterior AMI treated with pPCI. It is possible that neutrophilia and high MPV are simple surrogate markers of worse microvascular injury in patients with AMI.

Usefulness of combined white blood cell count and plasma glucose for predicting in-hospital outcomes after acute myocardial infarction

Admission white blood cell (WBC) count and plasma glucose (PG) have been associated with adverse outcomes after acute myocardial infarction (AMI). This study investigated the joint effect of WBC count and PG on predicting in-hospital outcomes in patients with AMI. WBC count and PG were measured at the time of hospital admission in 3,665 patients with AMI. Patients were stratified into tertiles (low, medium, and high) based on WBC count and PG. Patients with a high WBC count had a 2.0-fold increase in in-hospital mortality compared with those with a low WBC count. Patients with a high PG level had a 2.7-fold increase in mortality compared with those with a low PG level. When a combination of different strata for each variable was analyzed, a stepwise increase in mortality was seen. There was a considerable number of patients with a high WBC count and low PG level or with a low WBC count and high PG level. These patients had an intermediate risk, whereas those with a high WBC count and high PG level had the highest risk, i.e., 4.8-fold increase in mortality, compared with those with a low WBC count and low PG level. Multivariate analysis was performed to assess the predictor for in-hospital mortality using WBC count and PG level as continuous variables and showed that WBC count and PG level were independently associated with in-hospital mortality. These findings suggested that a simple combination of WBC count and PG level might provide further information for predicting outcomes in patients with AMI.

Successful reperfusion for acute ST elevation myocardial infarction is associated with a decrease in WBC count

BACKGROUND

Elevated white blood cell (WBC) count on admission in patients with ST segment elevation myocardial infarction (STEMI) has been associated with an adverse prognosis. Whether successful reperfusion by primary percutaneous coronary intervention (PCI) is associated with a decrease in WBC count is unknown.

METHODS

In this subanalysis of the On-TIME trial, WBC count was measured on admission and 6 h and 24 h after primary PCI for STEMI (n = 364). Angiographic measurements of reperfusion, including TIMI-flow and myocardial blush grade, were compared with changes in WBC count.

RESULTS

Restoration of TIMI 3 flow by primary PCI was associated with a significant decrease in median WBC count (11.5 (9.7-14.2), 10.7 (9.0-12.5), 9.9 (8.5-11.5) at baseline, 6 h and 24 h), whereas after unsuccessful PCI (TIMI < 3 flow) WBC count remained elevated (12.5 (9.5-14.6), 12.1 (9.9-14.4), and 11.4 (9.2-15.2)). Improved myocardial blush was also related to a decrease in WBC count. After multivariate analysis, improved myocardial perfusion (TIMI 3 flow and myocardial blush grade 3) was an independent predictor of a decrease of WBC count after PCI.

CONCLUSION

Impaired myocardial reperfusion after primary PCI for STEMI is associated with persistent WBC elevation.

Association of white blood cell count with systolic blood pressure within the normotensive range

Hypertension and inflammation promote cardiovascular disease (CVD). Even high normal systolic blood pressure (SBP) is associated with increased CVD risk. We assessed the relationship of elevated SBP within the normotensive range and white blood cell (WBC) count. This is a cross-sectional study of 3484 white asymptomatic individuals (mean age: 43+/-8 years, 79% males) without hypertension with SBP<140 mm Hg. White blood cell count >or=75th percentile (8.35 x 10(9) cells/l) was considered cutoff for elevated WBC. Subjects were classified into three levels of SBP (first: <120 mm Hg, n=1,176, 34%; second: 120-129 mm Hg, n=1,654, 47%; third: 130-139 mm Hg, n=654, 19%). Mean WBC count increased linearly across SBP categories (first: 6.14+/-1.54, second: 6.20+/-1.52, third: 6.41+/-1.62, P=0.02 for trend). There was a linear increase in prevalence of elevated WBC across higher SBP categories (22, 24 and 28%, P=0.02). As compared to those with SBP<120 mm Hg, in multivariate linear regression analyses (adjusting for age, gender, smoking status, diabetes, body mass index, physical activity, cholesterol/high-density lipoprotein cholesterol ratio) WBC count was significantly higher among participants with SBP 130-139 mm Hg (regression coefficient: 2.64, 95% confidence interval: 1.04-4.24, P=0.001). Odds ratio for prevalence of elevated WBC with SBP<120 mm Hg as reference group was 1.14 (0.92-1.41) for SBP 120-129 mm Hg and 1.50 (1.15-1.92) for SBP 130-139 mm Hg. In conclusion, Higher SBP within the normotensive range is also associated with elevated WBC count. Further studies are needed to clarify the role of inflammation in high normal SBP and associated CVD risk.

Impact of prodromal angina pectoris and white blood cell count on outcome of patients with acute myocardial infarction

BACKGROUND

Elevation of white blood cell (WBC) count at admission is associated with adverse outcome after acute myocardial infarction (AMI). Prodromal angina, by the mechanism of ischemic preconditioning, improves left ventricular (LV) function and survival after reperfusion therapy in patients with AMI. Recent experimental studies have reported that preconditioning has anti-inflammatory effect.

METHODS

This study consisted of 598 patients with first anterior wall AMI who underwent coronary angiography within 12 h after symptom onset. WBC count was measured at the time of hospital admission. Prodromal angina was defined as angina occurring within 24 h before the onset of AMI. Serial measurements of LV ejection fraction (EF) were obtained before reperfusion therapy and before discharge in 421 patients (71%).

RESULTS

High WBC count (>10.2 x 103/mm3, n=297) was associated with higher 30-day mortality (8% vs. 4%, p=0.02) and lower predischarge LVEF (51+/-15% vs. 57+/-14%, p<0.001), although there was no significant difference in acute LVEF (47+/-10% vs. 49+/-11%, p=0.07). High WBC count was an independent predictor of 30-day mortality (p=0.009) and predischarge LVEF (p=0.002). Prodromal angina was associated with lower 30-day mortality (3% vs. 7%, p=0.02) and preserved predischarge LVEF (57+/-15% vs. 53+/-14%, p=0.006). Patients with prodromal angina had lower WBC count (10.0+/-3.3 x 10(3)/mm3 vs. 11.0+/-3.9 x 10(3)/mm3, p=0.001) and prodromal angina was an independent predictor of WBC count (p<0.001).

CONCLUSIONS

Elevation of WBC count and lack of prodromal angina were associated with impaired LV function and mortality after reperfusion in patients with AMI. Prodromal angina might have contributed to favorable outcome after AMI through its anti-inflammatory effect.

Relation between white blood cell counts and myocardial reperfusion in patients with recanalized anterior acute myocardial infarction

BACKGROUND

The clinical significance of the white blood cell (WBC) count on admission in relation to the duration of ischemia in acute myocardial infarction (AMI) remains unclear.

METHODS AND RESULTS

The relationship of the WBC count on admission to myocardial reperfusion was examined in 135 patients with recanalization of an anterior AMI within 6 h of symptom onset. Patients were classified according to the WBC count on admission: Group L (n=75), WBC count <12,000 cells/mm(3) and group H (n=60), WBC count >or=12,000 cells/mm(3). Peak creatine kinase (CK) was higher and impaired myocardial reperfusion, defined as a myocardial blush grade of 0/1, was more frequent in group H than in group L. Among the patients in group H, those with early (<or=3 h) recanalization had a lower QRS score before recanalization than those with late (>3 h) recanalization; however, peak CK and the incidence of impaired myocardial reperfusion were similar in these subgroups of patients. Multivariate analysis showed that WBC count >or=12,000 cells/mm(3) on admission was an independent predictor of impaired myocardial reperfusion in patients with early recanalization (odds ratio 7.9, p=0.04), but not in those with late recanalization.

CONCLUSIONS

A higher WBC count may be associated with progression of myocardial damage after recanalization in patients with early recanalization of an anterior AMI.