Onset Of Acute Myocardial Infarction Symptoms Research Articles

The impact of systemic changes on quality of care providing in acute myocardial infarction in Ukraine

For the past 5 years, the system of providing medical care to patients with acute myocardial infarction (AMI) has radically changed in Ukraine. The accession of our country to the European initiative "Stent for Life" contributed to the creation of the national reperfusion network. It ensured the wide availability of medical care for patients with AMI due to the fastest delivery of patients to clinics that provide a 24-hour emergency coronary artery stenting. Nowadays in Ukraine, 42 reperfusion centers are successfully operating 24/7/365 care delivery and more than 50% of patients with AMI undergo primary percutaneous coronary intervention (PCI). Almost 70% of patients are delivered to clinics within the first 6 hours after the onset of AMI symptoms, which corresponds to the obligatory “therapeutic window” for emergency PCI. The average number of primary PCI performed in AMI increased by 4 times in 2018 compared to 2012, reaching 286 procedures per 1 million population. The structure of reperfusion therapy has qualitatively changed in 2016. The total number of reperfusion procedures increased due to a decrease of thrombolytic therapy cases and an increase in the frequency of using the most effective method – primary coronary stenting in patients with STEMI. Systemic changes in the structure of medical care providing to patients with AMI contributed to a decrease in hospital lethality in patients with AMI - from 14,1% in 2012 to 13,81% in 2019.

Fe2O3@SiO2@Eu-MOF@Tb-MOF Core/Multishell Nanoparticles for the Fluorescence Sensing of Aspirin and Acute Myocardial Infarction Biomarkers

As a dangerous cardiovascular disease, acute myocardial infarction (AMI) has taken the lives of countless patients. Symptom onset of AMI is accompanied by a high amount of AMI biomarkers, including creatine kinase isoenzyme (CK-MB), troponin I (CTn I), and myoglobin (Mb). On the other hand, aspirin is an effective curing drug for AMI. Herein, we applied the layer-by-layer (LBL) synthesis strategy to form stratified magnetic core/multishell lanthanide metal–organic framework (Ln-MOF) Fe2O3@SiO2@Eu-MOF@Tb-MOF (MagMOF) nanoballs. Further, target mRNA sequence and antibodies (NH2-mRNA, anti-CTn, and anti-Mb) for AMI biomarkers are combined with MagMOF, respectively. They can be utilized as a hybrid sensing platform for the detection of CK-MB, Mb, and CTn I with high sensitivity (the limit of detection (LOD) for CK-MB is 174.98 U L–1, for CTn I is 0.16 mg L–1, and for Mb is 0.94 mg L–1). The detection ranges of MagMOF toward CK-MB, Mb, and CTn I in human serum have covered their maximum normal range in the human body, respectively. Further, MagMOF was applied in the ratiometric detection of aspirin with high sensitivity and low limit detection (LOD = 0.43 μM). As a result, MagMOF is the first example of realizing stable, susceptible, fast, and convenient detection of these AMI biomarkers and curing drug aspirin.

Non-optimum temperature increases risk and burden of acute myocardial infarction onset: A nationwide case-crossover study at hourly level in 324 Chinese cities.

SummaryBackgroundThe associations of ambient temperature with acute myocardial infarction (AMI) have seldom been examined based on the time of symptom onset.MethodsWe conducted a time-stratified case-crossover study among 1,046,773 eligible AMI patients from 2,093 hospitals in 324 Chinese cities from January 1, 2015 to June 30, 2021, after excluding those transferred from other hospitals or having not reported the time of symptom onset. Hourly exposure to ambient temperature was calculated as multiple moving 24-h averages (days) before hourly onset of AMI symptoms. Conditional logistic regression and distributed lag non-linear models with a duration of 0–21 days were used to estimate the cumulative associations of non-optimum temperature with AMI onset and the corresponding disease burden nationally. Subgroup analyses by region and period were conducted. Specifically, cities with and without centralized heating system were classified into heating and non-heating regions, respectively. The whole year in heating region was divided into heating and non-heating periods based on the duration of centralized heating in each city.FindingsAlmost monotonically increasing risks were observed for both overall AMI and its two subtypes when ambient temperature declined. The effects of extremely low temperature occurred immediately on the concurrent day, and lasted up to almost 3 weeks. The excess risks of AMI onset associated with non-optimum ambient temperatures were observed during the whole year in the non-heating region and non-heating period in the heating region, but not during heating period. Specifically, odds ratios of AMI onset associated with extremely low temperature cumulated over 0–21 days were 1.24 (95% CI: 1.13–1.37), 1.46 (95% CI: 1.20–1.76), and 1.62 (95% CI: 1.46–1.81) in the heating region during non-heating period, in the non-heating region during winter and non-winter period, respectively. The heat effects on AMI onset were very modest and transient. Totally, 13.26% of AMI cases could be attributable to non-optimum temperatures nationally. The burden of AMI attributable to non-optimum temperature was much smaller in heating region than in non-heating region. Somewhat stronger effects were observed in females and patients aged older than 65.InterpretationThis nationwide study provided robust evidence that non-optimum ambient temperature may significantly trigger AMI onset, and for the first time estimated the disease burden after accounting for spatial and seasonal heterogeneity. Centralized heating might substantially mitigate AMI burden due to non-optimum temperature.FundingShanghai International Science and Technology Partnership Project, National Natural Science Foundation of China, Talent Training Program of Zhongshan Hospital, Fudan University.

Transition from Syringe to Autoinjector Based on Bridging Pharmacokinetics and Pharmacodynamics of the P2Y12 Receptor Antagonist Selatogrel in Healthy Subjects

Selatogrel is a potent, reversible, and selective antagonist of the platelet P2Y12 receptor currently developed for the treatment of acute myocardial infarction(AMI). In the completed Phase I/II studies, selatogrel was subcutaneously(s.c.) administered as a lyophilizate-based formulation by syringe by a healthcare professional. In the Phase III study, selatogrel will be self-administered s.c. as a liquid formulation with an autoinjector at the onset of AMI symptoms to shorten treatment delay. This clinical bridging study compared the pharmacokinetics(PK) of selatogrel between the different formulations. This was a single-center, randomized, open-label, three-period, cross-over Phase I study in 24 healthy subjects. In each period, a single subcutaneous dose of 16 mg selatogrel was administered as (1) a Phase III liquid formulation by autoinjector (Treatment A), (2) a Phase III liquid formulation by prefilled syringe (Treatment B), or (3) a Phase I/II reconstituted lyophilizate-based formulation by syringe (Treatment C). PK parameters including area under the plasma concentration-time curve from zero to infinity (AUC0-∞), maximum plasma concentration (Cmax), time to reach Cmax(tmax), and terminal half-life(t1/2) were determined using noncompartmental analysis. Pharmacodynamic(PD) parameters were estimated using PK/PD modeling, including the time of first occurrence of inhibition of platelet aggregation(IPA) ≥80% (tonset), duration of IPA above 80% (tduration), and responder rate defined as the percentage of subjects with tonset ≤30min and tduration ≥3h. Safety and tolerability were also assessed. Comparing Treatment A to Treatment C, the exposure (AUC0-∞) was bioequivalent with a geometric mean ratio(GMR) (90% confidence interval) of 0.95 (0.92-0.97) within the bioequivalence range (0.80-1.25). Absorption following Treatment A was slightly slower with atmax occurring approximately 30min later and a 20% lower Cmax. The autoinjector itself had no impact on the PK of selatogrel, as similar values of Cmax and AUC0-∞ were determined after administration as a Phase III liquid formulation by autoinjector or by prefilled syringe (i.e., GMR [90% confidence interval] of 1.06 [0.97-1.15] and 0.99 [0.96-1.03] for Cmax and AUC0-∞, respectively). PK/PD modeling predicted that the median tonset will occur slightly later for Treatment A (7.2min) compared to Treatment C (4.2 min), while no relevant differences in tduration and responder rate were estimated between the two treatments. Selatogrel was safe and well tolerated following all three treatments. PK and simulated PD effects of selatogrel were similar across treatments. NCT04557280.

Cardiogenic Shock Among Patients with and without Acute Myocardial Infarction in a Latin American Country: A Single-Institution Study.

Background:Latin America has limited information about the full spectrum cardiogenic shock (CS) and its hospital outcome. This study sought to examine the temporal trends, clinical features and outcomes of patients with CS in a coronary care unit of single Mexican institution.Methods:This was a retrospective study of consecutive patients hospitalized with CS in a Mexican teaching hospital between 2006–2019. Patients were classified according to the presence or absence of acute myocardial infarction (AMI).Results:Of 22,747 admissions, 833 (3.7%) exhibited CS. Among patients with AMI (n = 12,438), 5% had AMI–CS, and in patients without AMI (n = 10,309), 2.3% developed CS (non-AMI–CS). Their median age was 63 years and 70.5% were men. Cardiovascular risk factors were more frequent among the AMI–CS group, whereas a history of heart failure was greater in non-AMI–CS patients (70.1%). In AMI-CS patients, the median delay time was 17.2 hours from the onset of AMI symptoms to hospital admission. Overall, the median left ventricular ejection fraction (LVEF) was 30%. Patients with CS at admission showed end-organ dysfunction, evidenced by lactic acidosis, renal impairment, and elevated liver transaminases. Of the 620 AMI–CS patients, the main cause was left ventricular dysfunction in 71.3%, mechanical complications in 15.2% and right ventricular infarction in 13.5%. Among the 213 non-AMI–CS patients, valvular heart disease (49.3%) and cardiomyopathies (42.3%) were the most frequent etiologies. In-hospital all-cause mortality rates were 69.7% and 72.3% in the AMI–CS and non-AMI–CS groups, respectively. Among AMI–CS patients, renal dysfunction, diabetes, older age, depressed LVEF, absence of revascularization and the use of mechanical ventilation were independent predictors of in-hospital mortality. However, in the non-AMI–CS group, only low LVEF and high lactate levels proved significant.Conclusions:This study demonstrates differences in the epidemiology of CS compared to high-income countries; the high mortality reflects critically ill patients and the lack of contemporary effective therapies in the population studied.

5232Inhibition of platelet aggregation after subcutaneous administration of a single-dose of selatogrel, a novel P2Y12 antagonist, in acute myocardial infarction: a randomised open-label phase 2 study

Abstract Background Oral P2Y12 receptor antagonists exhibit a delayed onset of platelet inhibition in patients experiencing acute myocardial infarction (AMI). Selatogrel is a potent, reversible, and highly selective P2Y12 receptor antagonist with a rapid onset and offset of action when administered subcutaneously. Purpose To assess inhibition of platelet aggregation (IPA) after subcutaneous (s.c.) single-dose administration of selatogrel in patients with AMI receiving standard concomitant therapy. Methods Male and postmenopausal female adults (≤85 years) presenting with type 1 AMI (ST-elevation MI [STEMI] or non-STEMI [NSTEMI]) and onset of AMI symptoms >30 min to <6 h were randomised (1:1) to receive a single s.c. dose of either 8 mg or 16 mg selatogrel. Blood samples were collected at baseline and at 15, 30, and 60 min post-dose and evaluated for ADP-induced platelet aggregation (expressed as P2Y12 reaction units [PRU]) using VerifyNow. The primary endpoint was the response to treatment (defined by PRU <100) at 30 min post-dose. Safety was assessed up to 48 h post-dose. Results Forty-seven patients (median age 69 y; 72% male; 62% STEMI; 94% Killip class 1) received 8 mg (N=24) or 16 mg (N=23) selatogrel. Study-treatment concomitant medications included acetylsalicylic acid (98%), P2Y12 inhibitors (96%), heparins (94%), statins (94%), nitrates (68%) and morphine (38%). Oral ticagrelor (92%) with corresponding loading doses was only administered after selatogrel. The proportion of patients meeting the primary endpoint (responders) 30 min post-dose was 91% (95% CI: 72, 99) and 95% (95% CI: 77, 100) with 8 and 16 mg, respectively (p<0.001 for both doses). Response rates were independent from STEMI/NSTEMI diagnosis, age and sex. A response was observed as early as 15 min (8 mg: 75% of patients [95% CI: 53, 90]; 16 mg: 91% of patients [95% CI: 72, 99]), and sustained up to 60 min post-dose (8 mg: 75% of patients [95% CI: 53, 90]; 16 mg: 96% of patients [95% CI: 78, 100]). Platelet reactivity was decreased following selatogrel administration (Figure; interquartile range [box], min and max [whiskers], median and mean [horizontal line and symbol, respectively, within the box]). Overall, 43% of patients had ≥1 treatment-emergent adverse event (TEAE), which were mainly of mild/moderate intensity. Ventricular tachycardia ([VT] 8 mg: 5/24; 16 mg: 3/23) was the most frequent TEAE. Treatment-emergent serious AEs of VT were reported in two patients receiving 8 mg (one patient also experienced ventricular fibrillation) and one patient receiving 16 mg selatogrel. Post-procedural haemorrhage (mild) occurred in one patient: bleeding at radial access after percutaneous coronary intervention (∼1 h after selatogrel 8 mg). Conclusion Single-dose administration of s.c. selatogrel (8 mg and 16 mg) induced a rapid IPA response in patients with AMI at 30 min (as early as 15 min and maintained at 60 min post-dose) and was well-tolerated with no major bleeding events. Acknowledgement/Funding Fully funded by Idorsia Pharmaceuticals Ltd

Use of Mobile Devices, Social Media, and Crowdsourcing as Digital Strategies to Improve Emergency Cardiovascular Care: A Scientific Statement From the American Heart Association.

Cardiac arrest, acute myocardial infarction (AMI), and stroke affect millions of people in the United States annually.1 Despite significant advances in medical treatments for these conditions, they remain a major public health problem and a leading cause of morbidity and mortality.1 A critical common element in optimizing care and outcomes for these conditions is the timely recognition of symptoms and initiation of treatment. For example, rapid initiation of cardiopulmonary resuscitation (CPR) is associated with improved survival from cardiac arrest.2 Similarly, early recognition and presentation after onset of symptoms of AMI and ischemic stroke enable implementation of critical therapies such as primary angioplasty and thrombolysis, which are known to improve outcomes.1 Indeed, the “Chain of Survival” for emergency cardiovascular and cerebrovascular care (ECCC) starts with prompt identification of the condition and early activation of the healthcare system to rapidly initiate care.3 Unfortunately, despite national efforts that include public education initiatives and clinical practice guideline recommendations from entities such as the American Heart Association (AHA), major gaps remain in the timely identification of symptoms and initiation of ECCC.4–6 As one example, studies of out-of-hospital cardiac arrest (OHCA) have consistently noted delays in the initiation of bystander CPR.7 For AMI, there have been advances in the provision of timely primary angioplasty for ST-segment elevation myocardial infarction (STEMI), as reflected by significant improvements in door-to-balloon times.8 However, the time from patient symptom onset to seeking care for possible myocardial infarction has not improved significantly.9,10 Similarly, for stroke, there continue to be advances in door-to-needle times, but stroke symptom recognition and seeking of treatment by patients and their families remain a major barrier to timely stroke care.11–16 Public and clinician education efforts alone are not sufficient to reduce gaps …

Association of Level of Physical Exertion with Acute Myocardial Infarction in Bangladeshi Population

Background: Evidences suggest that heavy physical exertion can trigger the onset of acute myocardial infarction. But there have been no clean cut data in Bangladesh about the risk of myocardial infarction during and after heavy exertion. To address this question the study was conducted.Methods: It was a multicentre cross sectional study was conducted from July 2012 to June 2013 with patient of diagnosed acute myocardial infarction (AMI) admitted in department of cardiology of National Institute of Cardiovascular Diseases (NICVD), Bangabandhu Sheikh Mujib Medical University (BSMMU) and Dhaka Medical College Hospital (DMCH). From selected samples, two hours activity prior to onset of symptom of AMI was asked according to standard questionnaire. Activities were quantified on a scale from 1 to 8 metabolic equivalents (METs) according to generally accepted values. Collected data were analyzed by SPSS version 16.Results: In this study 246 patients (74 .4 percent of whom were men; mean age [±SD], 64.68 ± 7.63 years) were interviewed. The study showed that 11.38% patients were engaged in strenuous physical exertion (e” 6 METs) within two hours prior to symptom onset of AMI. Strenuous exertion group of AMI patients were all most all sedentary worker [26 (92.86%) of 28]. Most of the patients (82.14 %) of strenuous group had history of less than 8 hours work per day. Strenuous exertion group had history of longtime exertion (72.57%, 1-2 hours) than non-strenuous group (42.66%, <0.5 hours). Moreover, 67.86% AMI patients of strenuous exertion group had experienced irregular exertion whereas most of the patients (64.22%) of non strenuous group had a history of regular exertion.Conclusions: The result of the study indicates that a period of strenuous physical activity is associated with increased risk of having AMI, particularly among patients of sedentary worker who have dyslipidemia and who exercise irregularly. Those who exercise regularly have lower chances of AMI as shown by the negative correlation.Cardiovasc. j. 2016; 8(2): 115-122

Correlation of plasma catestatin level and the prognosis of patients with acute myocardial infarction.

Catestatin is a peptide which is a potent inhibitor of catecholamine secretion and played essential functions in the cardiovascular system. Previous research found that dramatic changes of catestatin were associated with hemodynamics in acute myocardial infarction (AMI) during the first week after the AMI symptoms onset, but whether catestatin is also involved in the pathophysiological progression after AMI and then a predictor for outcomes is not clear. The aim of this study is to determine the correlation of plasma catestatin levels at different time points and the prognosis of AMI. 100 participants recruited were all patients with AMI, all of who received successful primary percutaneous coronary intervention (PCI) within 12h from the AMI symptom onset in our center; the concentrations of plasma catestatin were evaluated from blood samples of those 100 participants. Subsequent 65 months' follow-up was performed after discharging to evaluate cardiac adverse events and the association between catestatin levels and prognosis of AMI was examined. We confirmed the dramatic change of catestatin concentrations in the first week of AMI, and the levels of catestatin on D3 were much higher in adverse events group than those in non-adverse events group (p<0.0001), but the ratio of D7/D3 was significantly lower. In addition, the Kaplan-Meier analysis showed that the groups in which the levels on D3 were higher (p<0.0001) and the ratios of D7/D3 were lower (p<0.0001), patients trended to be more susceptive to adverse events after AMI. Furthermore, according to the analysis, we surmised catestatin level on D3 as an appropriate predictor for outcomes in patients with AMI with good specificity as well as sensitivity. All of the evidence confirmed that catestatin plays an important role in the progress of AMI, and may act as a promising target for prognostic prediction.

Plasma microRNA-133a is a new marker for both acute myocardial infarction and underlying coronary artery stenosis

BackgroundPrevious study demonstrated that miR-133a was released into blood from injured myocardium in cardiovascular diseases. However, the dynamic change of circulating miR-133a level in the early phase of acute myocardial infarction (AMI) and the correlation between miR-133a and severity of coronary stenosis in coronary heart disease (CHD) patients are not clear.Methods and resultsThree different cohorts (including 13 AMI patients, 176 angina pectoris patients and 127 control subjects) were enrolled to investigate the expression levels of circulating miR-133a in patients with myocardial ischemia and also the relationship between plasma miR-133a and severity of coronary stenosis. Plasma miR-133a levels of participants were examined by real-time quantitative PCR. Simultaneously, plasma cardiac troponin I (cTnI) concentrations were measured by ELISA assays. The results showed that circulating miR-133a level was significantly increased in AMI patients in time-dependent manner, and achieved a 72.1 fold peak at 21.6 ± 4.5 hours after the onset of AMI symptoms and exhibited a similar trend to plasma cTnI level. We also found that plasma miR-133a levels were higher in CHD patients than control group. Importantly, the levels of circulating miR-133a positively correlated with the severities of the coronary artery stenosis. Receiver operating characteristic (ROC) analysis revealed that circulating miR-133a had considerable diagnostic accuracy for CHD with an AUC of 0.918 (95% confidence interval 0.877-0.960).ConclusionsCirculating miR-133a may be a new biomarker for AMI and as a potential diagnostic tool. And increased miR-133a level may be used to predict both the presence and severity of coronary lesions in CHD patients.

Relation of Outbursts of Anger and Risk of Acute Myocardial Infarction

The aim of the present study was to explore the association between outbursts of anger and acute myocardial infarction (AMI) risk. Outbursts of anger are associated with an abrupt increase in cardiovascular events; however, it remains unknown whether greater levels of anger intensity are associated with greater levels of AMI risk or whether potentially modifiable factors can mitigate the short-term risk of AMI. We conducted a case-crossover analysis of 3,886 participants from the multicenter Determinants of Myocardial Infarction Onset Study, who were interviewed during the index hospitalization for AMI from 1989 to 1996. We compared the observed number and intensity of anger outbursts in the 2 hours preceding AMI symptom onset with its expected frequency according to each patient's control information, defined as the number of anger outbursts in the previous year. Of the 3,886 participants in the Determinants of Myocardial Infarction Onset Study, 1,484 (38%) reported outbursts of anger in the previous year. The incidence rate of AMI onset was elevated 2.43-fold (95% confidence interval 2.01 to 2.90) within 2 hours of an outburst of anger. The association was consistently stronger with increasing anger intensities (p trend <0.001). In conclusion, the risk of experiencing AMI was more than twofold greater after outbursts of anger compared with at other times, and greater intensities of anger were associated with greater relative risks. Compared with nonusers, regular β-blocker users had a lower susceptibility to heart attacks triggered by anger, suggesting that some drugs might lower the risk from each anger episode.

The impact of successful manual thrombus aspiration on in-stent restenosis after primary PCI

This study sought to investigate the impact of successful manual thrombus aspiration on angiographic in-stent restenosis and clinical outcome in patients treated by bare metal stent implantation for ST-segment elevation acute myocardial infarction. There are very limited data on the impact of manual thrombus aspiration on the occurrence of in-stent restenosis after bare metal stent implantation. This was a prospective, randomized, single-center study. Patients (N=60) presenting within 12 h of ST-segment elevation acute myocardial infarction symptom onset were randomized to primary percutaneous coronary intervention (PCI) with (N=30) or without (N=30) upfront manual thrombus aspiration using the Export aspiration catheter. All patients underwent control coronary angiography after 6 months. Baseline, clinical, and angiographic preprocedural findings did not differ between the two groups. Patients who underwent successful manual thrombus aspiration had significantly higher minimal lumen diameter after 6 months (2.25±0.90 vs. 1.63±0.76, P=0.005), significantly lower percentage diameter stenosis (28.81 vs. 45.03%, P=0.017), and significantly lower late lumen loss (0.73±0.84 vs. 1.18±0.79, P=0.035). There was a trend for lower rate of major adverse cardiocerebrovascular events such as death, myocardial reinfarction, stroke, and target lesion revascularization in the same group of patients (16.67 vs. 26.67%, P=0.347). Successful upfront manual thrombus aspiration during primary PCI showed beneficial effects on the reduction of in-stent restenosis after bare metal stent implantation compared with standard PCI.

CIRCULATING MIR-195, MIR-30A AND LET-7B ASSOCIATED WITH ACUTE MYOCARDIAL INFARCTION

ObjectivesMicroRNAs (miRNAs) play key roles in diverse biological and pathological processes, including the regulation of proliferation, apoptosis and angiogenesis cellular differentiation. Recently, circulating miRNAs have been reported as potential biomarkers...

Triggering of acute myocardial infarction by different means of transportation

Prior studies have reported an association between traffic-related air pollution in urban areas and exacerbation of cardiovascular disease. We assess here whether time spent in different modes of transportation can trigger the onset of acute myocardial infarction (AMI). We performed a case-crossover study. We interviewed consecutive cases of AMI in the KORA Myocardial Infarction Registry in Augsburg, Southern Germany between February 1999 and December 2003 eliciting data on potential triggers in the four days preceding myocardial infarction onset. A total of 1459 cases with known date and time of AMI symptom onset, who had survived 24 hours after the onset, completed the registry's standard interview on potential triggers of AMI. An association between exposure to traffic and AMI onset 1 hour later was observed (odds ratio: 3.2; 95% confidence interval [CI]: 2.7-3.9, p < 0.001). Using a car was the most common source of traffic exposure; nevertheless, times spent in public transport or on a bicycle were similarly associated with AMI onset 1 hour later. While the highest risk for AMI onset was within 1 hour of exposure to traffic, the elevated risk persisted for up to 6 hours. Women, patients aged 65 years or older, patients not part of the workforce, and those with a history of angina or diabetes exhibited the largest associations between times spent in traffic and AMI onset 1 hour later. The data suggest that transient exposure to traffic regardless of the means of transportation may increase the risk of AMI transiently.

Influence of diurnal variation in the size of acute myocardial infarction

ObjectiveTo evaluate whether the size of acute myocardial infarction (AMI) shows circadian variability. DesignAn observational, prospective study. SettingA 12-bed coronary care unit. PatientsConsecutive patients diagnosed with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. InterventionsThe patients were divided into two groups according to the time of onset of AMI symptoms (group A: 0–12h, group B: 12–24h). Main variables of interestAge, sex, cardiovascular risk factors, coronary anatomy, left ventricular ejection fraction, infarct location, time from onset of symptoms to reperfusion, presence of heart failure upon admission, and peak troponin I value. ResultsA total of 108 patients with a diagnosis of STEMI were included. Patients in group A showed a higher troponin I concentration compared to group B (troponin I: 70.85±16.38ng/ml vs 60.90±22.92ng/ml, p=0.003). In the multivariate analysis the onset of AMI between 0 and 12h was identified as an independent predictor of infarct size (OR: 1.133, 95%CI 1.012–1.267, p=0.01). ConclusionsAn onset of AMI between 0 and 12h results in a significantly larger final size of necrosis compared with any other time of presentation.

Influencia de la variabilidad diurna en el tamaño del infarto agudo de miocardio

Objective To evaluate whether the size of acute myocardial infarction (AMI) shows circadian variability. Design An observational, prospective study. Setting A 12-bed coronary care unit. Patients Consecutive patients diagnosed with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. Interventions The patients were divided into two groups according to the time of onset of AMI symptoms (Group A: 0-12 hours, Group B: 12-24 hours). Main variables of interest Age, sex, cardiovascular risk factors, coronary anatomy, left ventricular ejection fraction, infarct location, time from onset of symptoms to reperfusion, presence of heart failure upon admission, and peak troponin I value. Results A total of 108 patients with a diagnosis of STEMI were included. Patients in group A showed a higher troponin I concentration compared to group B (troponin I: 70.85 ± 16.38 versus 60.90 ± 22.92 ng / ml, p = 0.003). In the multivariate analysis the onset of AMI between 0-12 hours was identified as an independent predictor of infarct size (OR: 1.133, 95%CI 1.012-1.267, p = 0.01). Conclusions An onset of AMI between 0-12 hours results in a significantly larger final size of necrosis compared with any other time of presentation.

Factors associated with delayed hospital arrival among patients with acute myocardial infarction: a cross‐sectional study in Greece

It is proven that early admission to hospital contributes significantly to the successful management of acute myocardial infarction (AMI). This study aimed to examine the factors associated with delayed hospital arrival among patients with AMI. A cross-sectional study among 477 AMI patients was conducted during a 2-year period in two large tertiary hospitals in Greece. Structured face-to-face interviews were conducted and information regarding their socio-demographic characteristics, medical history and factors that might be correlated with delayed hospital arrival were collected. The main factors that were found to be correlated with delayed hospital arrival among AMI patients were the absence of companion/attendant/escort present during the AMI [odds ratio (OR) 2.1, 95% confidence interval (CI) 0.98-4.4, P = 0.049], previous medical history of diabetes mellitus (OR 3.4, CI 1.6-7.2, P = 0.002), absence of dyspepsia (OR 9.2, CI 3.6-23.3, P < 0.001) and nausea/vomiting symptoms (OR 16.9, CI 4.1-69.1, P < 0.001), and also being at a distance of more than 10 km from the hospital (OR 19.6, CI 5.4-70.6, P < 0.001). A number of factors that might delay hospital arrival among patients with AMI should be taken into account in healthcare service planning. Health policy actions that will improve the accessibility to healthcare services, the restructuring of the Greek primary healthcare system and the provision of effective patient education by nurses could reduce the pre-hospital delay. The study was conducted in two hospitals which limits the generalization of the findings. Also, the onset of AMI symptoms relied on self-report by the patients.

Circulating MicroRNAs are Promising Novel Biomarkers of Acute Myocardial Infarction

Recent studies have revealed that microRNAs (miRNAs) are involved in the regulation of cardiac development, physiologic, and pathologic processes via post-transcriptional control of gene expression. The stable circulating miRNAs offer unique opportunities for the early diagnosis of several diseases. In this study, we examined the circulating miR-133 and miR-328 levels from patients with acute myocardial infarction (AMI). Twenty-eight control subjects and fifty-one consecutive AMI patients were enrolled. The plasma and whole blood samples from AMI patients were obtained within 24 hours (n=51) and 7 days (n=6) after the onset of AMI symptoms. The circulating miR-133 and miR-328 levels were analyzed using quantitative real-time PCR. The miR-133 levels in plasma from AMI patients exhibited a 4.4-fold increase compared with control subjects (p=0.006). Moreover, the increased miR-133 levels in whole blood were comparable with those in plasma samples. In contrast, the miR-328 levels in plasma and whole blood of AMI patients were markedly increased by 10.9-fold and 16.1-fold, respectively, compared to those in control subjects (p=0.033 and p<0.001). The elevated circulating miR-133 and miR-328 levels were recovered to the control levels at 7 days after AMI. In addition, there was a correlation between circulating miR-133 or miR-328 levels and cardiac troponin I. Furthermore, circulating miR-133 or miR-328 showed no significant changes in AMI patients with tachyarrhythmia (n=24) or bradyarrhythmia (n=26) compared to those in patients without arrhythmias. Receiver operating characteristic curve analysis revealed that the areas under the curve of miR-133 or miR-328 in plasma and whole blood were 0.890, 0.702 and 0.810, 0.872, respectively (all p<0.05). The miR-133 and miR-328 levels in plasma and whole blood in AMI patients were increased compared to those in control subjects. These miRNAs may represent novel biomarkers of AMI.

E0643 Effects of no-reflow phenomenon identified by myocardial blush grades on systolic function and synchrony in patients with acute myocardial infarction after PCI

ObjectiveTo investigate the effect of no-reflow phenomenon after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI).MethodsA total of 128 patients with the first AMI of the anterior...

Intensity of physical exertion and triggering of myocardial infarction: a case-crossover study

Acute myocardial infarction (AMI) can be precipitated or triggered by discrete transient exposures including physical exertion. We evaluated whether the risk of having an AMI triggered by physical exertion exhibits an exposure-response relationship, and whether it varies by ambient temperature or by taking place indoors or outdoors. We conducted a case-crossover study within the Myocardial Infarction Registry in Augsburg, Germany in 1999-2003. One thousand three hundred and one patients reported levels of activity and time spent outdoors on the day of AMI and three preceding days in an interview. The case-crossover analyses showed an association of physical exertion with AMI symptom onset within 2 h, which was strong for strenuous exertion (METs >or= 6) [relative risk (RR) 5.7, 95% confidence interval (CI) 3.6-9.0), and still significant for moderate exertion (METs = 5) (RR 1.6, 95% CI 1.2-2.1) compared to very light or no exertion. Strenuous exertion outside was associated with a four-fold larger RR of AMI symptom onset than exertion performed indoors, which was not explained by temperature. This study confirms previous results and shows a graded exposure-response relationship between physical exertion intensity and triggering of AMI onset. These findings may have implications for behavioural guidance of people at risk of AMI.