Why do we keep missing left circumflex artery myocardial infarctions?

BACKGROUND: Diagnosis of left circumflex artery (LCx) myocardial infarctions via 12­lead electrocardiogram (ECG) has posed a challenge to healthcare professionals for many years. METHODS AND RESULTS: A retrospective observational study was performed to analyze patients admitted with myocardial infarction. The study used electronic medical records and specific ICD-10 codes to identify eligible patients, resulting in 2032 encounters. After independent adjudication of cardiac biomarkers, coronary angiography, and electrocardiographic changes, a final patient population of 58 encounters with acute occlusion myocardial infarction (OMI) with a culprit LCx lesion was established. OMI was defined as a lesion with either thrombolysis in myocardial infarction flow (TIMI) 0-2 or TIMI 3 with Troponin I > 1 ng/mL (Reference range 0.00-0.03 ng/mL). ECGs of these patients were then independently evaluated and grouped into 8 different classifications based on the presence or absence of ST elevation and/or depression in corresponding leads. ECG patterns and anatomical characteristics (proximal or distal to the first obtuse marginal artery) of the LCx lesions were then correlated. The appropriateness of triage and delay in reperfusion therapy were also assessed. Those with a left dominant or codominant circulation, and with LCx lesions proximal to the first obtuse marginal artery, were more likely to present with no or subtle ST-segment changes that led to delays in reperfusion therapy. CONCLUSIONS: Patients with left or codominant coronary artery circulation, with OMI proximal to the first obtuse marginal artery, may be less likely to have "classic" findings of ST-segment elevation on ECG due to cancellation forces in the limb leads.

1-Year Mortality Prediction through Artificial Intelligence Using Hemodynamic Trace Analysis among Patients with ST Elevation Myocardial Infarction.

Background and Objectives: Patients presenting with ST Elevation Myocardial Infarction (STEMI) due to occlusive coronary arteries remain at a higher risk of excess morbidity and mortality despite being treated with primary percutaneous coronary intervention (PPCI). Identifying high-risk patients is prudent so that close monitoring and timely interventions can improve outcomes. Materials and Methods: A cohort of 605 STEMI patients [64.2 ± 13.2 years, 432 (71.41%) males] treated with PPCI were recruited. Their arterial pressure (AP) wave recorded throughout the PPCI procedure was analyzed to extract features to predict 1-year mortality. After denoising and extracting features, we developed two distinct feature selection strategies. The first strategy uses linear discriminant analysis (LDA), and the second employs principal component analysis (PCA), with each method selecting the top five features. Then, three machine learning algorithms were employed: LDA, K-nearest neighbor (KNN), and support vector machine (SVM). Results: The performance of these algorithms, measured by the area under the curve (AUC), ranged from 0.73 to 0.77, with accuracy, specificity, and sensitivity ranging between 68% and 73%. Moreover, we extended the analysis by incorporating demographics, risk factors, and catheterization information. This significantly improved the overall accuracy and specificity to more than 76% while maintaining the same level of sensitivity. This resulted in an AUC greater than 0.80 for most models. Conclusions: Machine learning algorithms analyzing hemodynamic traces in STEMI patients identify high-risk patients at risk of mortality.

Identification of Cx43 variants predisposing to ventricular fibrillation in the acute phase of ST-elevation myocardial infarction.

AIMS: Ventricular fibrillation (VF) occurring in the acute phase of ST-elevation myocardial infarction (STEMI) is the leading cause of sudden cardiac death worldwide. Several studies showed that reduced connexin 43 (Cx43) expression and reduced conduction velocity increase the risk of VF in acute myocardial infarction (MI). Furthermore, genetic background might predispose individuals to primary VF (PVF). The primary objective was to evaluate the presence of GJA1 variants in STEMI patients. The secondary objective was to evaluate the arrhythmogenic impact of GJA1 variants in STEMI patients with VF. METHODS AND RESULTS: The MAP-IDM prospective cohort study included 966 STEMI patients and was designed to identify genetic predisposition to VF. A total of 483 (50.0%) STEMI patients with PVF were included. The presence of GJA1 variants increased the risk of VF in STEMI patients [from 49.1 to 70.8%, P = 0.0423; odds ratio (OR): 0.40; 95% confidence interval: 0.16-0.97; P = 0.04]. The risk of PVF decreased with beta-blocker intake (from 53.5 to 44.8%, P = 0.0085), atrial fibrillation (from 50.7 to 26.4%, P = 0.0022), and with left ventricular ejection fraction >50% (from 60.2 to 41.4%, P < 0.0001). Among 16 GJA1 variants, three novel heterozygous missense variants were identified in three patients: V236I, H248R, and I327M. In vitro studies of these variants showed altered Cx43 localization and decreased cellular communication, mainly during acidosis. CONCLUSION: Connexin 43 variants are associated with increased VF susceptibility in STEMI patients. Restoring Cx43 function may be a potential therapeutic target to prevent PVF in patients with acute MI. CLINICAL TRIAL REGISTRATION: Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT00859300.

Prognostic Impact of Prehospital Simple Risk Index in Patients With ST-Elevation Myocardial Infarction.

BACKGROUND: The simple risk index recorded in the emergency room (ER-SRI), which is calculated using the formula (heart rate × [age / 10]2) / systolic blood pressure, was shown to be able to stratify the prognosis in ST-elevation myocardial infarction (STEMI) patients. However, the prognostic impact of the prehospital simple risk index (Pre-SRI) remains unknown.Methods and Results: This study enrolled 2,047 STEMI patients from the Mie Acute Coronary Syndrome (ACS) registry. Pre-SRI was calculated using prehospital data and ER-SRI was calculated using emergency room data. The primary endpoint was 30-day all-cause mortality. The cut-off values of Pre-SRI and ER-SRI for predicting 30-day mortality were 34.8 and 34.1, with accuracies of 0.816 and 0.826 based on receiver operating characteristic analyses (P<0.001 for both). There was no difference in the accuracy of the 2 indices. Multivariate Cox regression analysis demonstrated that a High Pre-SRI (≥34) was a significant independent predictor of 30-day mortality. With combined Pre-SRI and ER-SRI assessment, patients with High Pre-SRI/High ER-SRI showed significantly higher mortality than those with High Pre-SRI/Low ER-SRI, Low Pre-SRI/High ER-SRI, and Low Pre-SRI/Low ER-SRI (P<0.001). The addition of High Pre-SRI to High ER-SRI showed incremental prognostic value of the Pre-SRI. CONCLUSIONS: Pre-SRI can identify high-risk STEMI patients at an early stage and combined assessment with Pre-SRI and ER-SRI could be of incremental prognostic value for risk stratification in STEMI patients.

Characterization of prehospital time delay in primary percutaneous coronary intervention for acute myocardial infarction: analysis of geographical infrastructure-dependent and -independent components.

BACKGROUND: Prehospital delay in reaching a percutaneous coronary intervention (PCI) facility is a major problem preventing early coronary reperfusion in patients with ST-elevation myocardial infarction (STEMI). The aim of this study was to identify modifiable factors that contribute to the interval from symptom onset to arrival at a PCI-capable center with a focus on geographical infrastructure-dependent and -independent factors. METHODS: We analyzed data from 603 STEMI patients who received primary PCI within 12 h of symptom onset in the Hokkaido Acute Coronary Care Survey. We defined onset-to-door time (ODT) as the interval from the onset of symptoms to arrival at the PCI facility and we defined door-to-balloon time (DBT) as the interval from arrival at the PCI facility to PCI. We analyzed the characteristics and factors of each time interval by type of transportation to PCI facilities. In addition, we used geographical information system software to calculate the minimum prehospital system time (min-PST), which represents the time required to reach a PCI facility based on geographical factors. We then subtracted min-PST from ODT to find the estimated delay-in-arrival-to-door (eDAD), which represents the time required to reach a PCI facility independent of geographical factors. We investigated the factors related to the prolongation of eDAD. RESULTS: DBT (median [IQR]: 63 [44, 90] min) was shorter than ODT (median [IQR]: 104 [56, 204] min) regardless of the type of transportation. However, ODT was more than 120 min in 44% of the patients. The min-PST (median [IQR]: 3.7 [2.2, 12.0] min) varied widely among patients, with a maximum of 156 min. Prolongation of eDAD (median [IQR]: 89.1 [49, 180] min) was associated with older age, absence of a witness, onset at night, no emergency medical services (EMS) call, and transfer via a non-PCI facility. If eDAD was zero, ODT was projected to be less than 120 min in more than 90% of the patients. CONCLUSIONS: The contribution of geographical infrastructure-dependent time in prehospital delay was substantially smaller than that of geographical infrastructure-independent time. Intervention to shorten eDAD by focusing on factors such as older age, absence of a witness, onset at night, no EMS call, and transfer via a non-PCI facility appears to be an important strategy for reducing ODT in STEMI patients. Additionally, eDAD may be useful for evaluating the quality of STEMI patient transport in areas with different geographical conditions.

Peak early diastolic strain rate improves prediction of adverse cardiovascular outcomes in patients with ST-elevation myocardial infarction.

BACKGROUND: The prognostic role of diastolic dysfunction measured by the circumferential peak early diastolic strain rate (PEDSR) on ST-elevation myocardial infarction (STEMI) is not completely established. OBJECTIVES: We aimed to investigate the prognostic value of diastolic function by measuring PEDSR within 1 week after STEMI. METHODS: The cardiac magnetic resonance (CMR) pictures of 420 subjects from a clinical registry study (NCT03768453) were analyzed and the composite major adverse cardiac events (MACEs) were followed up. RESULTS: The PEDSR of patients was significantly lower compared with that of control subjects (P < 0.001). Within the median follow-up period of 52 months, PEDSR of patients who experienced MACEs deceased more significantly than that of patients without MACEs (P < 0.001). After adjusting with clinical or CMR indexes, per 0.1/s reduction of PEDSR increased the risks of MACEs to 1.402 or 1.376 fold and the risk of left ventricular (LV) remodeling to 1.503 or 1.369 fold. When PEDSR divided by best cutoff point, significantly higher risk of MACEs (P < 0.001) and more remarkable LV remodeling (P < 0.001) occurred in patients with PEDSR ≤ 0.485/s. Moreover, when adding the PEDSR to the conventional prognostic factors such as LV ejection fraction and infarction size, better prognostic risk classification models were created. Finally, aging, tobacco use, remarkable LV remodeling, and a low LV ejection fraction were factors related with the reduction of PEDSR. CONCLUSIONS: Diastolic dysfunction has an important prognostic effect on patients with STEMI. Measurement of the PEDSR in the acute phase could serve as an effective index to predict the long-term risk of MACEs and cardiac remodeling.

ST-elevation myocardial infarction among cardiac amyloidosis patients; a national readmission database study.

Literature regarding recent trends, mortality outcomes of ST-elevation myocardial infarction (STEMI) in cardiac amyloidosis (CA) patients is limited.To study coronary interventions, and trends in prevalence and mortality outcomes among CA patients with STEMI.Data from the national readmissions database (NRD) sample that constitutes 49.1% of the stratified sample of all hospitals in the USA, representing more than 95% of the national population, were analyzed for hospitalizations associated with CA with STEMI. A linear p-trend was used to assess the trends.Out of the total 4252 adult patients (mean age 73.3 ± 11.7 years, 40.2% females) with diagnosis of CA, 439 (10.3%) had STEMI while 3813 (89.7%) had no STEMI. STEMI-CA patients had higher rates of multi-organ manifestations including VT/VF (12% vs 8.5%; p-value < 0.001), cardiogenic shock (12.7% vs 7.3%; p < 0.001), AKI requiring dialysis (5.3% vs 4%; p < 0.001), and ICU admissions (25.2% vs 15.3%; p < 0.001) compared to CA without STEMI. CA-STEMI had increased mortality rates (23.7% vs 16.1%, p < 0.001) compared to CA without STEMI. On multivariate logistic regression analysis, coronary interventions including PCI (OR 0.6, CI 0.4-1.1; p = 0.3) and CABG (OR 0.7, CI 0.3-1.8; p = 0.2) had no association with mortality among CA patients. The absolute yearly trends for prevalence and mortality associated with STEMI in CA patients remained steady over the study years (linear p-trends 0.2 and 0.6, respectively).CA-STEMI is associated with significant complications and mortality. Coronary interventions may not have significant mortality benefits. Thus, more research will be needed to improve mortality rates among these patients.

Endovascular therapeutic hypothermia adjunctive to percutaneous coronary intervention in acute myocardial infarction: realistic simulation as a game changer.

BACKGROUND: Endovascular therapeutic hypothermia (ETH) reduces the damage by ischemia/reperfusion cell syndrome in cardiac arrest and has been studied as an adjuvant therapy to percutaneous coronary intervention (PCI) in ST-elevation myocardial infarction (STEMI). New available advanced technology allows cooling much faster, but there is paucity of resources for training to avoid delays in door-to-balloon time (DTB) due to ETH and subsequently coronary reperfusion, which would derail the procedure. The aim of the study was to describe the process for the development of a simulation, training & educational protocol for the multidisciplinary team to perform optimized ETH as an adjunctive therapy for STEMI. METHODS AND RESULTS: We developed an optimized simulation protocol using modern mannequins in different realistic scenarios for the treatment of patients undergoing ETH adjunctive to PCI for STEMIs starting from the emergency room, through the CathLab, and to the intensive care unit (ICU) using the Proteus® Endovascular System (Zoll Circulation Inc™, San Jose, CA, USA). The primary endpoint was door-to-balloon (DTB) time. We successfully trained 361 multidisciplinary professionals in realistic simulation using modern mannequins and sham situations in divisions of the hospital where real patients would be treated. The focus of simulation and training was logistical optimization and educational debriefing with strategies to reduce waste of time in patient's transportation from different departments, and avoiding excessive rewarming during transfer. Afterwards, the EHT protocol was successfully validated in a trial randomizing 50 patients for 18 minutes cooling before coronary recanalization at the target temperature of 32 ± 1.0 ∘C or PCI-only. A total of 35 patients underwent ETH (85.7% [30/35] in 90 ± 15 minutes), without delays in the mean door-to-balloon time for primary PCI when compared to 15 control group patients (92.1 minutes versus 87 minutes, respectively; p = 0.509). CONCLUSIONS: Realistic simulation, intensive training and educational debriefing for the multidisciplinary team propitiated feasible endovascular therapeutic hypothermia as an adjuvant therapy to primary PCI in STEMI. CLINICALTRIALS: gov: NCT02664194.

Left Ventricular Thrombus Management After Acute Myocardial Infarction in Clinical Practice: Results from LEVITATION Survey and Narrative Review.

PURPOSE: Left ventricular thrombus (LVT) after ST-elevation myocardial infarction still presents diagnostic and therapeutic challenges. The LEVITATION survey was designed to take a picture of LVT management in current clinical practice. METHODS: The survey covered diagnostic, therapeutic, and prophylactic issues and was completed by 104 European cardiac centers. Most of them (59%) were university or tertiary centers. RESULTS: The survey showed anterior apical a-/dyskinesia, large MI, spontaneous echo-contrast, late presentation with delayed PCI, and TIMI flow 0-1 as the most important perceived risk factors for LVT formation. Serial ultrasound imaging is the most used tool to diagnose LVT (88% of the centers), with contrast-enhanced ultrasound and cardiac MR performed in case of poor apex visualization or spontaneous echo-contrast. One third (34%) of the centers uses prophylactic anticoagulation to prevent LVT formation. In the presence of LVT, low molecular weight heparin is the most used in-hospital therapy. At discharge, vitamin K antagonist and direct oral anticoagulants are used in 67 and 32% of the cases, respectively. Triple antithrombotic therapy with aspirin plus clopidogrel and VKA is the most used strategy at discharge (55%), whereas a single antiplatelet therapy is preferred only in the case of moderate-to-high risk of bleeding. To assess LVT total regression, half of the centers use contrast-enhanced ultrasound and/or cardiac-MR. The duration of anticoagulation is usually 3-6 months (55%), with long-term prolongation in case of LVT persistence or recurrence. CONCLUSION: The survey has depicted for the first time the current real-world management of this neglected topic and has highlighted several grey zones that are still present and not supported by evidence.

COVID-19 lockdown impact on quality of treatment and outcomes of STEMI and stroke patients in a large tertiary medical center: an observational study.

BACKGROUND: The coronavirus 2019 (COVID-19) pandemic affected health-care systems worldwide, leading to fewer admissions and raising concerns about the quality of care. The objective of this study was to investigate the early effects of the COVID-19 pandemic on quality of care among stroke and ST-elevation myocardial infarction (STEMI) patients, focusing on clinical outcomes and direct treatment costs. METHOD: This retrospective, observational study was based on the 10-week period that included the first wave of the COVID-19 pandemic in Israel (15 February 2020-30 April 2020). Emergency department admissions for stroke and STEMI were compared with parallel periods in 2017-2019, focusing on demographics, risk and severity scores, and the effect of clinical outcomes on hospitalization costs. RESULTS: The 634 stroke and 186 STEMI cases comprised 16% and 19% fewer admissions, respectively, compared to 2019. No significant changes were detected in demographics, most disease management parameters, readmission and mortality outcomes. The mean door-to-balloon time increased insignificantly by 33%, lowering the health quality indicator (HQI) for treatment in <90 min from 94.7% in 2017-2019 to 83% in 2020 (P = 0.022). Among suspected stroke patients, 97.2% underwent imaging, with 28% longer median time from admission (P = 0.05). Consequently, only 24.3% met the HQI of imaging in <29 min, compared to 45.5% in 2017-2019 (P < 0.01). Increased length of stay and more intensive care unit admissions were the leading causes of 6.5% increased mean cost of STEMI patients' initial hospitalization, which totaled $29 300 in the COVID-19 period (P = 0.008). CONCLUSION: The initial pandemic period caused a decline in HQIs linked to diagnostic and treatment protocols, without changes in outcomes, but with increased hospitalization costs. Medical information and awareness of life-threatening conditions among patients and caregivers should be increased to enable proper diagnosis and management.

ST-Elevation Myocardial Infarction Outcomes: A United States Nationwide Emergency Departments Cohort Study.

BACKGROUND: Literature regarding trends in incidence and mortality of ST-elevation myocardial infarction (STEMI) in emergency departments (EDs) is limited. OBJECTIVE: To study the trends of incidence and mortality of STEMI. METHODS: Using the National Emergency Department Sample database in the United States, we identified all ED encounters for patients presenting with STEMI using International Classification of Diseases codes. A linear p-trend was used to assess the trends. RESULTS: Out of the 973 million ED encounters represented, 641,762 (65/100,000; mean age 69 [59-81] years, 35.8% female) adult patients were recorded with STEMI. Among the major complications associated with STEMI, a total of 49,401 (7.7%) had cardiac complications, which included acute heart failure (n = 9361, 1.6%), ventricular tachycardia or fibrillation (n = 12,267, 1.91%), conduction block (n = 20,165, 3.1%), and cardiogenic shock (n = 7608, 1.2%). There were 5675 (0.9%) patients recorded with cerebrovascular events, which included acute ischemic stroke among 5205 (0.8%) patients and 470 (0.1%) with transient ischemic attack. Acute kidney injury was recorded for 10,082 (1.6%) patients. The trend for incidence of STEMI in the ED had decreased from 7.76/10,000 in 2011 to 4.07/10,000 in 2018 (linear p-trend 0.0006). However, the yearly mortality of STEMI related to ED encounters had remained relatively steady: 7.56% in 2011 to 7.50% in 2018 (linear p-trend 0.2364). CONCLUSION: Despite the fact that the number of patients presenting to the ED with STEMI has been decreasing, the mortality trends have remained steady. Further research of in-hospital STEMI may yield opportunities to reduce the risk of complications, improve patient outcomes and decrease health care burden.

Renal Dysfunction as a Predictor of Slow-Flow/No-Reflow Phenomenon and Impaired ST Segment Resolution After Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction With Initial Thrombolysis in Myocardial Infarction Grade 0.

BACKGROUND: The slow-flow/no-reflow phenomenon and impaired ST segment resolution (STR) following primary percutaneous coronary intervention (PCI) in ST-elevation myocardial infarction (STEMI) predict unfavorable prognosis and are characterized by obstruction of the coronary microvascular. Several predictors of slow-flow/no-reflow have been revealed, but few studies have investigated predictors of slow-flow/no-reflow and STR exclusively in acute myocardial infarction patients with initial Thrombolysis in Myocardial Infarction (TIMI) Grade 0.Methods and Results:In all, 279 STEMI patients with initial TIMI Grade 0 were enrolled in the study. Slow-flow/no-reflow was defined as TIMI Grade <3 by angiography after PCI, and impaired STR was defined as STR <50% on an electrocardiogram after PCI. Slow-flow/no-reflow was observed in 31 patients. In multivariate analysis, estimated glomerular filtration rate (eGFR; odds ratio [OR] 0.97; P=0.007), a history of cerebrovascular disease (OR 4.65, P=0.007), time to recanalization ≥4 h (OR 2.76, P=0.023), and systolic blood pressure ≤90 mmHg (OR 3.45, P=0.046) were independent predictors of slow-flow/no-reflow. Impaired STR was observed in 102 of 248 patients with TIMI Grade 3. In multivariate analysis, eGFR (OR 0.94, P<0.001) and occlusion of the left anterior descending artery (OR 4.48, P<0.001) were independent predictors of impaired STR; eGFR was the only independent predictor of both slow-flow/no-reflow and impaired STR. CONCLUSIONS: Renal dysfunction may be related to coronary microvascular dysfunction and obstruction.

Dynamic evolvement of the de Winter ECG pattern.

The de Winter electrocardiograph (ECG) pattern in patients with chest pain is associated with occlusion of the proximal left anterior descending (LAD) artery. These patterns were once considered stable conditions, without dynamic evolution of ECG. Recently, several case reports have indicated that this ECG pattern may evolve into ST-elevation myocardial infarction (STEMI) or may follow the ECG manifestations of STEMI. However, our case report reveals a dynamic evolution from the de Winter pattern to STEMI and then to a normal ECG pattern.

Prognostic Significance of a Combination of QRS Score and E/e' Obtained 2 Weeks After the Onset of ST-Elevation Myocardial Infarction.

BACKGROUND: The early mitral inflow velocity to mitral early diastolic velocity ratio (E/e') and electrocardiogram (ECG) determination of QRS score are useful for risk stratification in patients with ST-elevation myocardial infarction (STEMI).Methods and Results:In this study, 420 consecutive patients (357 male; mean [±SD] age 63.6±12.2 years) with first-time STEMI who successfully underwent primary percutaneous coronary intervention within 12 h of symptom onset were followed-up for 5 years (median follow-up 67 months). Echocardiography, ECG, and blood samples were obtained 2 weeks after onset. Infarct size was estimated by the QRS score after 2 weeks (QRS-2wks) and creatine phosphokinase-MB concentrations (peak and area under the curve). The primary endpoint was death from cardiac causes or rehospitalization for heart failure (HF). During follow-up, 21 patients died of cardiac causes and 62 had HF. Multivariate Cox proportional hazard analysis showed that mean E/e' (hazard ratio [HR] 1.152; 95% confidence interval [CI] 1.088-1.215; P<0.0001), QRS-2wks (HR 1.153; 95% CI 1.057-1.254; P<0.0001), and hypertension (HR 1.702; 95% CI 1.040-2.888; P=0.03) were independent predictors of the primary endpoint. Kaplan-Meier curve analysis showed that patients with QRS-2wks >4 and mean E/e' >14 were at an extremely high risk of cardiac death or HF (log rank, χ2=116.3, P<0.0001). CONCLUSIONS: In patients with STEMI, a combination of QRS-2wks and mean E/e' was a simple but useful predictor of cardiac death and HF.

Prognostic value of fractalkine/CX3CL1 concentration in patients with acute myocardial infarction treated with primary percutaneous coronary intervention.

BACKGROUND: Recent studies demonstrated that fractalkine (FKN) is critically involved in the regulation of inflammation and cardiac function. OBJECTIVE: This study aimed to investigate the prognostic value of circulating FKN in patients with ST-elevated acute myocardial infarction (STEMI) after primary PCI. METHODS: We enrolled ninety consecutive STEMI patients and investigated the association of circulating FKN with myocardial salvage and the occurrence of major adverse cardiac events (MACE) after PCI. RESULTS: During a median follow-up of 387 days, total 15 MACE (16.67%) were registered in the study population. Patients with MACE were more likely to be occurred in elderly patients with 3-vessel disease. Correlation analysis demonstrated the level of FKN at day 1 after PCI (FKN@day-1) not only significantly correlated with the levels of hs-TnT at day 7 after PCI (R2 = 0.06; p = 0.02) but inversely correlated with the measurements of LVEF at 1-month observation (R2 = 0.10; p = 0.00). Kaplan-Meier survival analyses further revealed that patients with the level of FKN@day-1 above the median had a higher incidence of MACE compared with those whose FKN@day-1 levels below the median (log-rank test x2 = 13.29, p < 0.001). In addition, multivariate Cox regression analysis demonstrated that FKN@day-1 was an independent predictor of MACE (hazard ratio: 4.63; 95% confidence interval: 1.53-14.01; p = 0.00), together with WBC count and 3-vessel disease for STEMI patients. CONCLUSIONS: Our study demonstrates that FKN@day-1 is negative correlated with myocardial salvage after acute myocardial infarction and might be a valuable prognostic marker of MACE in patients with STEMI undergone PCI.

Glucose associated NETosis in patients with ST-elevation myocardial infarction: an observational study.

BACKGROUND: Neutrophil extracellular traps (NETs) have recently been identified as mediators in atherothrombosis. Although NETosis in general has been suggested to be glucose dependent, the transferability to patients with acute ST-elevation myocardial infarction (STEMI) is unclear. We assessed whether the NETs markers double-stranded deoxyribonucleid acid (dsDNA) and myeloperoxidase-DNA (MPO-DNA) associated with plasma glucose and the glucometabolic status in the acute phase and 3 months after a STEMI. We also explored whether an acute glucose load resulted in upregulated NETosis by assessment of peptidylarginine deiminase 4 (PAD4) gene expression. METHODS: In total, 224 STEMI patients were prospectively enrolled and underwent blood sampling acutely (median 16.5 h after PCI) and after 3 months. Glucometabolic status was defined based on the results of an oral glucose tolerance test (OGTT) as normal glucose regulation (NGR), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or type 2 diabetes (T2DM). dsDNA and MPO-DNA were measured in serum, while PAD4 mRNA was measured in circulating leukocytes by RT-PCR. RESULTS: dsDNA levels were significantly correlated to plasma glucose both acutely and after 3 months (r = 0.12 and r = 0.17, both p < 0.02), whereas MPO-DNA was not. No associations with the glucometabolic status were encountered for dsDNA and MPO-DNA acutely, but after 3 months dsDNA levels were elevated in patients with IFG and T2DM vs. NGR (428 vs. 371 ng/ml and 408 vs. 371 ng/ml, both p < 0.045). During the acute glucose load after 3 months, dsDNA and MPO-DNA remained unchanged while PAD4 mRNA increased significantly (RQ 0.836 vs. 0.920, p = 0.02). CONCLUSIONS: In this cohort of STEMI patients, levels of dsDNA associated with plasma glucose both in the acute and stable condition. The glucometabolic status was not substantially related to the selected NETs markers, however, an acute glucose load by OGTT performed after 3 months resulted in increased PAD4 expression, suggestive of enhanced NETosis in the aftermath of STEMI. TRIAL REGISTRATION: www.clinicaltrials.gov, NCT00926133 . Registered June 23, 2009.

Emergency Medical Services Utilization and Outcomes of Patients with ST-Elevation Myocardial Infarction in Lebanon.

BACKGROUND: Arrival of patients with ST-elevation myocardial infarction (STEMI) by Emergency Medical Services (EMS) results in shorter reperfusion times and lower mortality in developed countries. OBJECTIVES: This study examines EMS use by STEMI patients in Lebanon and associated clinical outcomes. METHODS: A retrospective observational study with chart review was carried out for STEMI patients arriving to the Emergency Department of a tertiary care center in Lebanon between January 1, 2013 and August 31, 2016. A descriptive analysis was done and followed by a bivariate analysis comparing two groups of patients (EMS vs. Non-EMS). RESULTS: A total of 280 patients were included in the study. They were mostly male (71.8%). Mean age was 65.1 years (95% confidence interval [CI] 63.4-66.9). Only 12.5% (95% CI 8.6-16.4) presented by EMS. Chest pain (81.1%) was the most common presenting symptom. Anterior myocardial infarction was the most common electrocardiogram (ECG) diagnosis (51.4%). Most patients were admitted (98.2%), and 72.0% of these patients were treated with primary percutaneous coronary intervention. Cardiogenic shock was the most frequent in-hospital complication (6.2%). The mortality rate was 7.1%. Mean door-to-ECG and door-to-balloon times were 10.8 (95% CI 7.1-14.4) min and 106.2 (95% CI 95.9-116.6) min, respectively. Patients' characteristics, presenting symptoms, outcomes, and performance metrics were similar between the two groups. CONCLUSION: EMS is underutilized by STEMI patients in Lebanon and is not associated with improvement in clinical outcomes. Medical oversight and quality initiatives focusing on outcomes of patients with timely sensitive emergencies are needed to advance the prehospital care system in Lebanon.

Assessment of the longitudinal changes in infarct heterogeneity post myocardial infarction.

BACKGROUND: Infarct heterogeneity, as assessed by determination of the peri-infarct zone (PIZ) by cardiac magnetic resonance imaging, has been shown to be an independent predictor for the development of cardiac arrhythmias and mortality post myocardial infarction (MI). The temporal evolution of the PIZ post MI is currently unknown. Thus, the main objective of our study was to describe the temporal evolution of the PIZ over a 6 month time period in contemporarily managed ST elevation myocardial infarction (STEMI) patients. Further, given the poor prognosis associated with microvascular obstruction (MVO) post STEMI, we sought to compare the temporal evolution of the PIZ in patients with and without MVO. We hypothesized that patients with MVO would show a relative persistence of PIZ over time when compared to those without MVO. METHODS: Twenty-one patients post primary percutaneous coronary intervention were enrolled and treated with evidence based therapy. Each patient had three cardiac MRI scans at 48 h, 3 weeks and 6 months post infarction. Repeated Measures Analysis of Variance (ANOVA) was used to assess the evolution of core infarct size and peri-infarct zone size across the three time frames. RESULTS: The patients in this study were predominantly male, with ~40 % LAD territory infarction and a mean LVEF of 46 ± 7 %. Core infarct size and PIZ size both decreased significantly across the three time frames. The presence of microvascular obstruction (MVO), a known adverse prognostic factor, influenced PIZ size. Both patients with and without MVO had a significant reduction in core infarct size over time. Patients with MVO did not have a significant change in PIZ size over time (11.9 ± 6.8 %, 12.2 ± 7.5 %, 10.7 ± 6.6 % p = 0.77). In contrast, non-MVO patients did have a significant decrease in PIZ size over time (7.0 ± 5.5 %, 7.1 ± 6.5 %, 2.7 ± 2.6 %, p = 0.01). CONCLUSIONS: Peri-infarct zone size, like core infarct size, varies depending upon the timing of measurement. Patients with MVO displayed a persistence of the PIZ over time.

T wave inversions in leads with ST elevations in patients with acute anterior ST elevation myocardial infarction is associated with patency of the infarct related artery.

OBJECTIVES: Following reperfusion therapy, early T wave inversions (TWI) have been shown to be a marker of successful reperfusion. We aimed to evaluate the relationship of TWI on the presenting ECG with spontaneous reperfusion as assessed by coronary angiography in patients with ST elevation (STE) myocardial infarction (STEMI). METHODS: Data of 146 consecutive patients presenting to the St. Luke's Episcopal Hospital Emergency Department with acute STEMI undergoing primary percutaneous coronary intervention (p-PCI) between January, 2007 and October, 2010 were retrospectively analyzed. Clinical data, ECG and angiographic data were reviewed. Patients were dichotomized based on T wave morphology on the presenting ECG into 2 groups - those with TWI and those with positive T waves (PTW). RESULTS: Thirty-one patients (21.2%) had TWI, while 115 (78.8%) had PTW. Sixty-four (43.8%) patients had anterior STE and 75 (51.3%) had inferior STE. Anterior STE was more likely to have TWI than non-anterior (29.7% vs. 14.6; p=0.014). By angiography, infarct related artery (IRA) patency (TIMI 2-3 flow) was seen in 45 (30.8%). TWI was more likely to be associated with IRA patency compared to PTW (51.6% vs. 25.2%; p=0.008). In patients with anterior STEMI and TWI, patent IRA was seen more frequently compared to those with PTW (68.4% vs. 20%; p<0.001). There was no association of T wave morphology and TIMI flow in patients with non-anterior STEMI. Patients presenting with stuttering symptoms were more likely to have TWI (70.4% vs. 10.2%; p <0.001) suggesting recurrent episodes of reperfusion and ischemia. CONCLUSIONS: In anterior STEMI patients, TWI on the presenting ECG is associated with spontaneous reperfusion. This relationship was not found among patients with non-anterior STEMI.

Discovery of plasma proteins associated with ventricular fibrillation during first ST-elevation myocardial infarction via proteomics.

AIMS: The underlying biological mechanisms of ventricular fibrillation (VF) during acute myocardial infarction are largely unknown. To our knowledge, this is the first proteomic study for this trait, with the aim to identify and characterize proteins that are associated with VF during first ST-elevation myocardial infarction (STEMI). METHODS AND RESULTS: We included 230 participants from a Danish ongoing case-control study on patients with first STEMI with VF (case, n = 110) and without VF (control, n = 120) before guided catheter insertion for primary percutaneous coronary intervention. The plasma proteome was investigated using mass spectrometry-based proteomics on plasma samples collected within 24 h of symptom onset, and one patient was excluded in quality control. In 229 STEMI patients {72% men, median age 62 years [interquartile range (IQR): 54-70]}, a median of 257 proteins (IQR: 244-281) were quantified per patient. A total of 26 proteins were associated with VF; these proteins were involved in several biological processes including blood coagulation, haemostasis, and immunity. After correcting for multiple testing, two up-regulated proteins remained significantly associated with VF, actin beta-like 2 [ACTBL2, fold change (FC) 2.25, P < 0.001, q = 0.023], and coagulation factor XIII-A (F13A1, FC 1.48, P < 0.001, q = 0.023). None of the proteins were correlated with anterior infarct location. CONCLUSION: Ventricular fibrillation due to first STEMI was significantly associated with two up-regulated proteins (ACTBL2 and F13A1), suggesting that they may represent novel underlying molecular VF mechanisms. Further research is needed to determine whether these proteins are predictive biomarkers or acute phase response proteins to VF during acute ischaemia.