Acute Ischemic Coronary Artery Disease and Ischemic Stroke: Similarities and Differences

Common and specific proteins and pathways in heart and cerebral ischemia

OBJECTIVE

To understand the similarities and differences between acute ischemic stroke and acute myocardial infarction (AMI) to help in the development of specific or common treatment strategies.

METHODS

Using an aptamer-based proteomic array, we measured and compared 1310 circulating proteins in the blood of 40 patients with AIS, 9 patients with AMI, and 31 healthy controls. Pathway enrichment analysis was performed using GSEA and g:profiler.

RESULTS

Ninety-four proteins were differentially expressed in AIS, and 284 were differentially expressed in AMI. Of these, 8 were specific to cerebral ischemia, and 197 were specific to myocardial infarction. Forty-two proteins were altered in both ischemia processes. Most altered pathways in AIS could be classified as immune response, cell cycle processing, molecular transport, or signaling. Pathways altered in AMI were mostly related to lipid metabolism and transport, highlighting cholesterol metabolic processes and estrogen signaling. In both types of ischemia, we found pathways related to metabolism, specifically purine metabolism, and signaling processes, such as TNF signaling or MAPK1/3.

CONCLUSIONS

The present study revealed proteins and pathways that were specifically altered in cerebral ischemia, in cardiac ischemia, or in both diseases, providing information on the similarities and differences of ischemic conditions. The role of common and specific proteins and pathways should be explored in detail to find possible therapeutic targets.

Sex-dependent effects of finerenone on hemostasis in normoglycemic and streptozotocin-induced diabetic mice

Diabetes is associated with aldosterone excess and the overactivation of its mineralocorticoid receptor (MR) which leads to the development of many cardiovascular dysfunctions. Therefore, MR antagonists have been found to exert favorable effects on the cardiovascular system. Finerenone is a new nonsteroidal MR antagonist approved for the treatment of chronic kidney disease associated with type 2 diabetes. Clinical studies have demonstrated that finerenone improves cardiovascular outcomes. However, its influence on hemostasis in the cardioprotective effect is unknown. Therefore, the main aim of our study was to evaluate the effects of finerenone (10 mg/kg, p.o.) on selected hemostasis parameters in streptozotocin (180 mg/kg, i.p.)-induced diabetes. Since regulation of the MR activity is sex-dependent, the study was conducted in both female and male mice. The most beneficial effects of finerenone were observed in diabetic female mice which included a decrease in thrombus formation, attenuation of platelet activity, inhibition of the coagulation system, and activation of fibrinolysis. In contrast, in male diabetic mice only an attenuation of the coagulation system was observed. Furthermore, finerenone also exerted unfavorable effects, but only in normoglycemic mice, manifested as a slight increase in platelet activity in males and an enhancement of the coagulation system activity in females. Our study is the first to show the sex-dependent and glycemia-dependent effects of finerenone on hemostasis in diabetes. The occurrence of beneficial effects only in female diabetic mice requires in-depth study.

Protocol of the Berlin Long-term Observation of Vascular Events (BeLOVE): a prospective cohort study with deep phenotyping and long-term follow up of cardiovascular high-risk patients

INTRODUCTION

The Berlin Long-term Observation of Vascular Events is a prospective cohort study that aims to improve prediction and disease-overarching mechanistic understanding of cardiovascular (CV) disease progression by comprehensively investigating a high-risk patient population with different organ manifestations.

METHODS AND ANALYSIS

A total of 8000 adult patients will be recruited who have either suffered an acute CV event (CVE) requiring hospitalisation or who have not experienced a recent acute CVE but are at high CV risk. An initial study examination is performed during the acute treatment phase of the index CVE or after inclusion into the chronic high risk arm. Deep phenotyping is then performed after ~90 days and includes assessments of the patient's medical history, health status and behaviour, cardiovascular, nutritional, metabolic, and anthropometric parameters, and patient-related outcome measures. Biospecimens are collected for analyses including 'OMICs' technologies (e.g., genomics, metabolomics, proteomics). Subcohorts undergo MRI of the brain, heart, lung and kidney, as well as more comprehensive metabolic, neurological and CV examinations. All participants are followed up for up to 10 years to assess clinical outcomes, primarily major adverse CVEs and patient-reported (value-based) outcomes. State-of-the-art clinical research methods, as well as emerging techniques from systems medicine and artificial intelligence, will be used to identify associations between patient characteristics, longitudinal changes and outcomes.

ETHICS AND DISSEMINATION

The study was approved by the Charité-Universitätsmedizin Berlin ethics committee (EA1/066/17). The results of the study will be disseminated through international peer-reviewed publications and congress presentations.

STUDY REGISTRATION

First study phase: Approved WHO primary register: German Clinical Trials Register: https://drks.de/search/de/trial/DRKS00016852; WHO International Clinical Registry Platform: http://apps.who.int/trialsearch/Trial2.aspx?TrialID=DRKS00016852. Recruitment started on July 18, 2017.Second study phase: Approved WHO primary register: German Clinical Trials Register DRKS00023323, date of registration: November 4, 2020, URL: http://www.drks.de/ DRKS00023323. Recruitment started on January 1, 2021.

Sex-dependent effects of canagliflozin and dapagliflozin on hemostasis in normoglycemic and hyperglycemic mice

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are antihyperglycemic drugs that decrease mortality from cardiovascular diseases. However, their effects on hemostasis in the cardioprotective effects have not been evaluated. Therefore, the effects of canagliflozin (CANA, 100 mg/kg, p.o.) and dapagliflozin (DAPA, 10 mg/kg, p.o.) on the parameters of hemostasis were investigated in female and male normoglycemic and streptozotocin (180 mg/kg, i.p.)-induced diabetic mice. CANA and DAPA reduced platelet activity in thrombus in male and female mice both normoglycemic and diabetic. CANA decreased thrombus formation in diabetic male mice, and platelet activation to ADP in diabetic female and male mice. Activation of fibrinolysis was observed in female mice, both normoglycemic and diabetic. DAPA reduced thrombus formation in diabetic male and female mice, and decreased platelet activation to ADP and fibrin formation in diabetic male mice. DAPA increased fibrin formation in normoglycemic female mice and activated fibrinolysis in diabetic female mice. CANA and DAPA exerted sex-specific effects, which were more pronounced in hyperglycemia. The antithrombotic effect of CANA and DAPA was more noticeable in male mice and could be due to platelet inhibition. The effect on coagulation and fibrinolysis was not clear since an increased coagulation and fibrinolysis were observed only in female mice.

Diffuse idiopathic skeletal hyperostosis is associated with incident stroke in patients with increased cardiovascular risk

OBJECTIVES

Earlier retrospective studies have suggested a relation between diffuse idiopathic skeletal hyperostosis [DISH] and cardiovascular disease, including myocardial infarction. The present study assessed the association between DISH and incidence of cardiovascular events and mortality in patients with high cardiovascular risk.

METHODS

In this prospective cohort study, we included 4624 patients (mean age 58.4 years, 69.6% male) from the Second Manifestations of ARTerial disease cohort. The main end point was major cardiovascular events [MACE: stroke, myocardial infarction, and vascular death]. Secondary endpoints included all-cause mortality and separate vascular events. Cause specific proportional hazard models were used to evaluate the risk of DISH on all outcomes, and subdistribution hazard models were used to evaluate the effect of DISH on the cumulative incidence. All models were adjusted for age, sex, body mass index, blood pressure, diabetes, non-HDL cholesterol, packyears, renal function, and C-reactive protein.

RESULTS

DISH was present in 435 (9.4%) patients. After a median follow-up of 8.7 (IQR 5.0-12.0) years, 864 patients had died and 728 patients developed a MACE event. DISH was associated with an increased cumulative incidence of ischaemic stroke.After adjustment in cause specific modelling, DISH remained significantly associated with ischaemic stroke (HR 1.55; 95%CI : 1.01-2.38), but not with MACE (HR 0.99; 95%CI : 0.79-1.24), myocardial infarction (HR 0.88; 95%CI : 0.59-1.31), vascular death (HR 0.94; 95%CI : 0.68-1.27), or all-cause mortality (HR 0.94; 95%CI : 0.77-1.16).

CONCLUSION

The presence of DISH is independently associated with an increased incidence and risk for ischaemic stroke, but not with MACE, myocardial infarction, vascular death, or all-cause mortality.

Carotid arterial wall MRI of apolipoprotein e-deficient mouse at 7 T using DANTE-prepared variable-flip-angle rapid acquisition with relaxation enhancement

PURPOSE

To optimize a sequence combining the delay alternating with nutation for tailored excitation (DANTE) preparative module with the variable-flip-angle rapid acquisition with relaxation enhancement (VF-RARE) sequence (DANTE-VF-RARE) and to investigate its feasibility for vessel wall imaging in Apolipoprotein E-Deficient (ApoE^-/-) mouse at 7 Tesla (T).

MATERIALS AND METHODS

Specific T1/T2 values were used for producing a sharper vessel wall in the variable-flip-angle optimization scheme. The DANTE RF pulse flip angle and pulse train length were optimized for maximizing the wall-lumen contrast. ApoE^-/- (fed high fat diet for 20/40/ 60 weeks, n = 9/4/4) and wild-type mice (controls, n = 3) were imaged at 7 T using VF-RARE, DANTE-VF-RARE, time-of-flight (TOF) angiography, and multi-slice T1-weighted 2D RARE coupled with inflow outflow saturation bands (IOSB-RARE). Wall-lumen contrast-to-noise-ratio efficiency (CNR_eff), lumen area (LA), and wall area (WA) were compared between DANTE-VF-RARE and 2D IOSB-RARE sequences. Additionally, linear regression analysis was conducted between MR measurements and histomorphometric planimetry results.

RESULTS

Residual blood signal was observed in the four out of eighteen carotids on VF-RARE images, whereas it was significantly suppressed on DANTE-VF-RARE images. Compared with IOSB-RARE, DANTE-VF-RARE offered significantly improved CNR_eff (P < 0.001). The LA and WA were both comparable (P = 0.085 and 0.112, respectively) and showed excellent agreement between DANTE-VF-RARE and IOSB-RARE (ICC = 0.96 and 0.95, respectively). The luminal stenosis identified by DANTE-VF-RARE was in consistent with the results of TOF. Strong correlations were found between MR measurements and histopathological analysis for both WA (DANTE-VF-RARE: r = 0.92, slope = 0.94, P < 0.001; IOSB-RARE: r = 0.93, slope = 0.94, P < 0.001) and LA (DANTE-VF-RARE: r = 0.82, slope = 0.54, P < 0.001; IOSB-RARE: r = 0.78, slope = 0.50, P < 0.001).

CONCLUSION

DANTE-VF-RARE achieves effective blood signal suppression and is a feasible approach for the 3D carotid arterial wall imaging of ApoE^-/- mouse at 7 T.

LncRNA RMRP accelerates hypoxia-induced injury by targeting miR-214-5p in H9c2 cells

OBJECTIVE

To elucidate the function of lncRNA RMRP in hypoxia-induced acute myocardial infarction (AMI) in vitro and explore its underlying mechanism.

METHODS

Hypoxic injury was confirmed by measurement of cell viability, LDH release, migration, invasion, and apoptosis in H9c2 cells. The interactions between RMRP and miR-214-5p as well as miR-214-5p and p53 were also investigated.

RESULTS

Hypoxia treatment significantly induced cell damage in H9c2 cells, accompanied with the up-regulation of RMRP expressions. Transfection of RMRP siRNA remarkably attenuated hypoxia-induced injury by enhancing cell viability, migration and invasion, and reducing cell apoptosis and LDH release; whereas, enforced expression of RMRP aggravated hypoxia-induced injury. Furthermore, RMRP served as an endogenous sponge for miR-214-5p, and its expression was negatively regulated by RMRP. The effects of RMRP knockdown on hypoxia-induced injury were further enhanced with miR-214-5p overexpression, but significantly abrogated with miR-214-5p silence. Moreover, p53 was verified as a direct target of miR-214-5p, and functional investigation revealed that RMRP regulated hypoxia-induced injury via modulating p53 signaling pathway, which was partially mediated by miR-214-5p.

CONCLUSION

Our findings demonstrated the novel molecular mechanism of RMRP/miR-214-5p/p53 axis on the regulation of hypoxia-induced myocardial injury in H9c2 cells, which might provide potential therapeutic targets for AMI treatment.

Detecting Myocardial Ischemia With 99mTechnetium-Tetrofosmin Myocardial Perfusion Imaging in Ischemic Stroke

BACKGROUND

To assess the myocardial status in patients with stroke, employing myocardial perfusion imaging (MPI) with ^99mTechnetium-tetrofosmin (^99mTc-TF)-single-photon emission computed tomography (SPECT).

METHODS

Fifty-two patients with ischemic stroke were subjected to ^99mTc-TF-SPECT MPI within 1 month after stroke occurrence. None of the patients had any history or symptoms of coronary artery disease or other heart disease. Myocardial perfusion imaging was evaluated visually using a 17-segment polar map. Myocardial ischemia (MIS) was defined as present when the summed stress score (SSS) was >4; MIS was defined as mild when SSS was 4 to 8, and moderate/severe with SSS ≥9. Patients with SSS >4 were compared to patients with SSS <4. Parameters such as age, body mass index, waist perimeter, smoking habits, and medical history (diabetes mellitus, dyslipidemia, etc) were evaluated according to MPI results.

RESULTS

Myocardial ischemia was present in 32 (62%) of 52 patients with stroke. Among them, 20 (62%) of 32 patients had mild abnormalities and 12 (38%) of 32 had moderate/severe. The age and waist perimeter showed a tendency to relate to severe MIS when patients with SSS >9 were compared to patients with SSS <4. In MPI-positive patients, an age was to be association with SSS, with the oldest age exhibiting the highest SSS (P = .01). The association of age with SSS remained statistically significant in the multivariate analysis (P = .04).

CONCLUSION

The study suggested that more than half of patients with stroke without a history of cardiac disease have MIS. Although most of them have mild MIS, we suggest a thorough cardiological evaluation in this group of patients for future prevention of severe myocardial outcome.

Increased Vascular Disease Mortality Risk in Prediabetic Korean Adults Is Mainly Attributable to Ischemic Stroke

Background and Purpose—

Prediabetes is a known risk factor for vascular diseases; however, its differential contribution to mortality risk from various vascular disease subtypes is not known.

Methods—

The subjects of the National Health Insurance Service in Korea (2002–2013) nationwide cohort were stratified into normal glucose tolerance (fasting glucose <100 mg/dL), impaired fasting glucose (IFG) stage 1 (100–109 mg/dL), IFG stage 2 (110–125 mg/dL), and diabetes mellitus groups based on the fasting glucose level. A Cox regression analysis with counting process formulation was used to assess the mortality risk for vascular disease and its subtypes—ischemic heart disease, ischemic stroke, and hemorrhagic stroke.

Results—

When adjusted for age, sex, and body mass index, IFG stage 2, but not stage 1, was associated with significantly higher all-cause mortality (hazard ratio [HR], 1.26; 95% confidence interval [CI], 1.18–1.34) and vascular disease mortality (HR, 1.27; 95% CI, 1.08–1.49) compared with normal glucose tolerance. Among the vascular disease subtypes, mortality from ischemic stroke was significantly higher (HR, 1.60; 95% CI, 1.18–2.18) in subjects with IFG stage 2 but not from ischemic heart disease and hemorrhagic stroke. The ischemic stroke mortality associated with IFG stage 2 remained significantly high when adjusted other modifiable vascular disease risk factors (HR, 1.51; 95% CI: 1.10–2.09) and medical treatments (HR, 1.75; 95% CI, 1.19–2.57).

Conclusions—

Higher IFG degree (fasting glucose, 110–125 mg/dL) was associated with increased all-cause and vascular disease mortality. The increased vascular disease mortality in IFG stage 2 was attributable to ischemic stroke, but not ischemic heart disease or hemorrhagic stroke in Korean adults.

Changes in ischemic stroke occurrence following daylight saving time transitions

BACKGROUND

Circadian rhythm disruption has been associated with increased risk of ischemic stroke (IS). Daylight saving time (DST) transitions disrupt circadian rhythms and shifts the pattern of diurnal variation in stroke onset, but effects on the incidence of IS are unknown.

METHODS

Effects of 2004-2013 DST transitions on IS hospitalizations and in-hospital mortality were studied nationwide in Finland. Hospitalizations during the week following DST transition (study group, n = 3033) were compared to expected hospitalizations (control group, n = 11,801), calculated as the mean occurrence during two weeks prior to and two weeks after the index week.

RESULTS

Hospitalizations for IS increased during the first two days (Relative Risk 1.08; CI 1.01-1.15, P = 0.020) after transition, but difference was diluted when observing the whole week (RR 1.03; 0.99-1.06; P = 0.069). Weekday-specific increase was observed on the second day (Monday; RR 1.09; CI 1.00-1.90; P = 0.023) and fifth day (Thursday; RR 1.11; CI 1.01-1.21; P = 0.016) after transition. Women were more susceptible than men to temporal changes during the week after DST transitions. Advanced age (>65 years) (RR 1.20; CI 1.04-1.38; P = 0.020) was associated with increased risk during the first two days, and malignancy (RR 1.25; CI 1.00-1.56; P = 0.047) during the week after DST transition.

CONCLUSIONS

DST transitions appear to be associated with an increase in IS hospitalizations during the first two days after transitions but not during the entire following week. Susceptibility to effects of DST transitions on occurrence of ischemic stroke may be modulated by gender, age and malignant comorbidities.

Imaging of carotid artery vessel wall edema using T2-weighted cardiovascular magnetic resonance

BACKGROUND

Atherothrombosis remains a major health problem in the western world, and carotid atherosclerosis is an important contributor to embolic ischemic strokes. It remains a clinical challenge to identify rupture-prone atherosclerotic plaques before clinical events occur. Inflammation, endothelial injury and angiogenesis are features of vulnerable plaques and may all be associated with plaque edema. Therefore, vessel wall edema, which can be detected by 2D T2-weighted cardiovascular magnetic resonance (CMR), may be used as a dynamic marker of disease activity in the atherosclerotic plaque. However, 2D imaging is limited by low spatial resolution in the slice-select direction compared to 3D imaging techniques. We sought to investigate the ability of novel 3D techniques to detect edema induced in porcine carotid arteries by acute balloon injury compared to conventional 2D T2-weighted black-blood CMR.

METHODS

Edema was induced unilaterally by balloon overstretch injury in the carotid artery of nine pigs. Between one to seven hours (average four hours) post injury, CMR was performed using 2D T2-weighted short-tau inversion recovery (T2-STIR), 3D volumetric isotropic turbo spin echo acquisition (VISTA) and 3D T2 prepared gradient-echo (T2prep-GE). The CMR images were compared in terms of signal-to-noise ratio (SNR) and contrast-to-noise (CNR) ratio. Furthermore, the presence of vessel wall injury was validated macroscopically by means of Evans Blue dye that only enters the injured vessel wall.

RESULTS

All three imaging sequences classified the carotid arteries correctly compared to Evans Blue and all sequences demonstrated a significant increase in SNR of the injured compared to the non-injured carotid vessel wall (T2-STIR, p = 0.002; VISTA, p = 0.004; and T2prep-GE, p = 0.003). There was no significant difference between sequences regarding SNR and CNR.

CONCLUSION

The novel 3D imaging sequences VISTA and T2prep-GE perform comparably to conventional 2D T2-STIR in terms of detecting vessel wall edema. The improved spatial coverage of these 3D sequences may facilitate visualization of vessel wall edema to enable detection and monitoring of vulnerable carotid atherosclerotic plaques.

Early time-dependent dynamic changes of TBET and GATA3 mRNA expressions in patients with acute coronary syndrome

Background. T-box expressed in T cells (TBET) and guanine adenine thymine adenine sequence-binding protein 3 (GATA3) play important roles in the differentiation of Th1 and Th2 subsets, which contributes to the progression of acute coronary syndrome (ACS). Objective. This study aimed to investigate the temporal change of TBET/GATA3 mRNA ratio in ACS. Methods. Thirty-three patients suspected of ACS with symptom onset within 24 hours were recruited. Blood samples were taken after arrival at the emergency department and at hourly intervals until the 6th hour. The mRNA expressions of TBET and GATA3 were quantified by a real-time RT-qPCR. Results. The TBET/GATA3 mRNA ratio was elevated dramatically in patients with acute myocardial infarction (AMI) and exhibited biphasic M-shaped release kinetics with two distinct peaks. The ratio was elevated 2 hours after symptom onset, dropped to the lowest level at 10 hours, and rose to the second peak at 14 hours. A similar biphasic M-shaped curve was observed in AMI patients with blood samples taken prior to any intervention. Conclusions. The TBET/GATA3 mRNA ratio was elevated in AMI patients throughout most of the first 20 hours after symptom onset. The biphasic M-shaped release kinetics was more likely to reflect pathophysiological changes rather than treatment effects.

Novel mutations in leukotriene C4 synthase and risk of cardiovascular disease based on genotypes from 50,000 individuals

BACKGROUND

Atherosclerosis is an inflammatory condition where cysteinyl leukotrienes have been identified to play an important role. Furthermore, cysteinyl leukotrienes may also affect thrombus formation. Using prospective, cross-sectional and case-control designs, we tested the hypothesis that hitherto unknown genetic variation, likely to affect the function of leukotriene C(4) synthase, is associated with risk of venous thromboembolism, ischemic stroke and myocardial infarction.

METHODS AND RESULTS

Resequencing the gene coding for leukotriene C(4) synthase in an extreme risk population with more than 1500 individuals revealed 17 new mutations, of which four are likely to change protein function (211G>A (minor allele frequency, 0.0001), IVS3 + 1G>A (0.002), 374G>A (0.0006) and 451_453+10del (0.0007)). Based on genotyping 50,000 individuals, age and sex adjusted odds ratios for venous thromboembolism were 2.0 (95% CI, 1.3-3.5) for IVS3+1G>A heterozygotes vs. wild type, and 1.9 (1.5-2.7) for any mutation heterozygote vs. wild type. Corresponding values were 2.0 (1.3-3.2) and 1.5 (1.1-2.1) for ischemic stroke, and 1.0 (0.8-1.3) and 1.2 (1.0-1.4) for myocardial infarction.

CONCLUSIONS

Four novel mutations that are likely to change the function of leukotriene C(4) synthase were associated with increased risk of venous thromboembolism and ischemic stroke. These findings need confirmation in other independent studies. In addition, the mechanism behind these findings deserves further investigation.

Inhibition of IFN regulatory factor-1 down-regulate Th1 cell function in patients with acute coronary syndrome

BACKGROUND

The crucial role of T helper (Th) cells and chronic inflammation in atherosclerosis and coronary artery disease is no longer controversial. Evidence has revealed that Th cell type 1 (Th1) is closely associated with the pathogenesis of acute coronary syndrome (ACS). But the mechanisms involved in the generation of Th1 cells have not been fully elucidated. IFN regulatory factor (IRF)-1 is a pleiotropic transcription factor involved in innate immunity and chronic inflammation disease. The study was undertaken to investigate the potential effect of IRF-1 on the Th1 cell function in patients with ACS in vitro.

METHODS

Patients with clinical presentation of chest pain, stable angina, unstable angina, and acute myocardial infarction were enrolled in this study. Circulating CD4+ T cells were enriched and analyzed for mRNA and protein expression of IRF-1. Silencing IRF-1 gene with small interfering RNA in CD4+ T cells from patients with ACS was performed to explore the possible mechanisms involved in ACS.

RESULTS

The results demonstrated that the expression of IRF-1 in CD4+ T cells was significantly increased in patients with ACS and positively correlated with plasma Th1 cytokine profile. Inhibition of IRF-1 in CD4+ T cells from patients with ACS prevented the induction of the frequencies and cytokines expression of Th1 cells. In addition, this study also revealed that IRF-1 modulate Th1 differentiation through establishing IL-12 responsiveness by acting on IL-12 receptor beta1.

CONCLUSION

The present data demonstrate that inhibition of IRF-1 obviously decrease the function of Th1 cells and may be a novel participator in the progress of ACS.

Causal relationship of susceptibility genes to ischemic stroke: comparison to ischemic heart disease and biochemical determinants

Interrelationships between genetic and biochemical factors underlying ischemic stroke and ischemic heart disease are poorly understood. We: 1) undertook the most comprehensive meta-analysis of genetic polymorphisms in ischemic stroke to date; 2) compared genetic determinants of ischemic stroke with those of ischemic heart disease, and 3) compared effect sizes of gene-stroke associations with those predicted from independent biochemical data using a mendelian randomization strategy. Electronic databases were searched up to January 2009. We identified: 1) 187 ischemic stroke studies (37,481 cases; 95,322 controls) interrogating 43 polymorphisms in 29 genes; 2) 13 meta-analyses testing equivalent polymorphisms in ischemic heart disease; and 3) for the top five gene-stroke associations, 146 studies (65,703 subjects) describing equivalent gene-biochemical relationships, and 28 studies (46,928 subjects) describing biochemical-stroke relationships. Meta-analyses demonstrated positive associations with ischemic stroke for factor V Leiden Gln506, ACE I/D, MTHFR C677T, prothrombin G20210A, PAI-1 5G allele and glycoprotein IIIa Leu33Pro polymorphisms (ORs: 1.11 – 1.60). Most genetic associations show congruent levels of risk comparing ischemic stroke with ischemic heart disease, but three genes—glycoprotein IIIa, PAI-1 and angiotensinogen—show significant dissociations. The magnitudes of stroke risk observed for factor V Leiden, ACE, MTHFR and prothrombin, but not PAI-1, polymorphisms, are consistent with risks associated with equivalent changes in activated protein C resistance, ACE activity, homocysteine, prothrombin, and PAI-1 levels, respectively. Our results demonstrate causal relationships for four of the most robust genes associated with stroke while also showing that PAI-1 4G/5G polymorphism influences cardiovascular risk via a mechanism not simply related to plasma levels of PAI-1 (or tPA) alone.

The hostile neck does not increase the risk of carotid endarterectomy

INTRODUCTION

Hostile neck anatomy is assumed to be associated with increased surgical risk for patients undergoing carotid endarterectomy (CEA) and is often considered a reason to choose carotid stenting or medical management. This retrospective case-control study evaluated whether, and how much, anatomically hostile necks represent a condition of higher surgical risk of early and late mortality and major or minor morbidity.

METHODS

The data for 966 homogeneous CEA patients was prospectively entered in a computer database. Seventy-seven had a hostile neck anatomy due to previous oncologic surgery or neck irradiation, restenoses after CEA, high carotid bifurcation, or bull-like and inextensible neck. A case-control matched-pair cohort study considered sex, age (5-year intervals), and year of operation. Regional anesthesia was used for all operations for atherosclerotic stenosis >or=70%, conforming to the European Carotid Surgery Trial (ECST) in symptomatic and asymptomatic patients, at a single center and by one surgeon or under his direct supervision.

RESULTS

The hostile neck patients and the control group were matched for age, sex, carotid-related symptoms, degree of stenoses, and main risk factors for cardiovascular diseases. Intraoperative variables were substantially equivalent in the two groups; however, procedure length and clamping time were, respectively, about 22 minutes (P = .0001) and 7 minutes longer (P = .01) in the hostile neck group. Rates of postoperative mortality and neurologic events were equivalent. Peripheral nerve lesions were multiple and significantly more frequent in the hostile neck patients (21% with >or=1 cranial nerve lesion vs 7% of controls, P = .03), yet all were transient and limited to a few months. The subgroups of patients with hostile neck, restenoses, and bull-like inextensible necks required the longest operative and clamping time, and those with bull-like and high bifurcation had the most frequent cranial nerve dysfunctions. At the respective follow-up of 47 and 45 months, survival curves (P = .48) and the incidence of restenoses and fatal and nonfatal strokes were similar (5 and 4, respectively).

CONCLUSIONS

Hostile necks led to more complex CEA procedures but without substantial consequences in early and late morbidity and mortality. Most patients with hostile neck can undergo CEA at low risk, with the benefit of effective long-lasting stroke prevention similar to standard patients. In our opinion, the more frequent but temporary cranial nerve dysfunctions that occur are not sufficient to consider hostile neck patients noneligible for CEA.

Leukotriene C4 synthase and ischemic cardiovascular disease and obstructive pulmonary disease in 13,000 individuals

Ischemic cardiovascular disease and obstructive pulmonary disease involve inflammation. Leukotrienes may be important pro-inflammatory mediators. We tested the hypothesis that the (-1072)G > A and (-444)A > C promoter polymorphisms of leukotriene C4 synthase confer risk of transient ischemic attack (TIA), ischemic stroke, ischemic heart disease (IHD), asthma, and chronic obstructive pulmonary disease (COPD). We genotyped individuals from the Danish general population, the Copenhagen City Heart Study, and Danish patients with IHD/coronary atherosclerosis, the Copenhagen Ischemic Heart Disease Study. We used prospective (n = 10,386), cross-sectional (n = 10,386), and case-control (n = 2392 + 5012) designs. Allele frequency was 0.07 for (-1072)A and 0.29 for (-444)C. Cumulative incidence for TIA was higher for (-1072)AA versus GG genotype (log-rank: p < 0.001), and lower for (-444)CC versus AA genotype (log-rank: p = 0.03). Cumulative incidence for ischemic stroke was also lower for (-444)CC versus AA genotype (log-rank: p = 0.04). Multifactorially adjusted hazard ratios for TIA were 5.2(95% CI:1.9-14) for (-1072)AA versus GG genotype, and 0.4(0.2-1.0) for (-444)CC versus AA genotype. Corresponding values were 1.9 (0.7-5.2) and 0.7 (0.5-1.0) for ischemic stroke, and 0.8 (0.4-1.6) and 1.0 (0.9-1.2) for IHD. In the case-control study, corresponding multifactorially adjusted odds ratios for IHD/coronary atherosclerosis were 0.5 (0.2-1.3) and 1.2 (1.0-1.5). These genotypes were not associated with risk of asthma or COPD. Leukotriene C4 synthase promoter genotypes influence risk of TIA and ischemic stroke, but not risk of IHD/coronary atherosclerosis, asthma, or COPD.