The pre-hospital electrocardiogram and time to reperfusion in patients with acute myocardial infarction, 2000-2002: findings from the National Registry of Myocardial Infarction-4

The enigma of the 'smoker's paradox': Results from a single-center registry of patients with STEMI undergoing primary percutaneous coronary intervention

BACKGROUND

Smoker's paradox usually refers to the observation of a favorable outcome of smoking patients in acute myocardial infarction.

METHODS

From April 2006 to December 2018 a population of 2456 patients with ST segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI) were prospectively enrolled in the MATRIX registry. Ischemic time, clinical, demographics, angiographic data, and 1-year follow-up were collected.

RESULTS

Among 2546 patients admitted with STEMI, 1007 (41 %) were current smokers. Smokers were 10 years younger and had lower crude in-hospital and 1-year mortality (1.5 % vs 6 %, p < 0.0001 and 5 % vs 11 %, p < 0.0001), shorter ischemic time (203 [147-299] vs 220 [154-334] minutes, p = 0.002) and shorter decision time (60 [30-135] vs 70 [36-170] minutes, p = 0.0063). Smoking habit [OR:0.37(95 % CI:0.18-0.75)-p < 0.01], younger age [OR 1.06 (95%CI:1.04-1.09)-p < 0.001] and shorter ischemic time [OR:1.01(95%CI:1.01-1.02)-p < 0.05] were associated to lower in-hospital mortality. Only smoking habit [HR:0.65(95 % CI: 0.44-0.9)-p = 0.03] and younger age [HR:1.08 (95%CI:1.06-1.09)-p < 0.001] were also independently associated to lower all-cause death at 1-year follow-up. After propensity matching, age, cardiogenic shock and TIMI flow <3 were associated with in-hospital mortality, while smoking habit was still associated with reduced mortality. Smoking was also associated with reduced mortality at 1-year follow-up (HR 0.54, 95 % CI [0.37-0.78]; p < 0.001).

CONCLUSIONS

Smoking patients show better outcome after PCI for STEMI at 1-year follow-up. Although "Smoking paradox" could be explained by younger age of patients, other factors may have a role in the explanation of the phenomenon.

Feasibility of patch-type wireless 12-lead electrocardiogram in laypersons

Various efforts have been made to diagnose acute cardiovascular diseases (CVDs) early in patients. However, the sole option currently is symptom education. It may be possible for the patient to obtain an early 12-lead electrocardiogram (ECG) before the first medical contact (FMC), which could decrease the physical contact between patients and medical staff. Thus, we aimed to verify whether laypersons can obtain a 12-lead ECG in an off-site setting for clinical treatment and diagnosis using a patch-type wireless 12-lead ECG (PWECG). Participants who were ≥ 19 years old and under outpatient cardiology treatment were enrolled in this simulation-based one-arm interventional study. We confirmed that participants, regardless of age and education level, can use the PWECG on their own. The median age of the participants was 59 years (interquartile range [IQR] = 56-62 years), and the median duration to obtain a 12-lead ECG result was 179 s (IQR = 148-221 s). With appropriate education and guidance, it is possible for a layperson to obtain a 12-lead ECG, minimizing the contact with a healthcare provider. These results can be used subsequently for treatment.

Temporal Trends in Reperfusion Delivery and Clinical Outcomes Following Implementation of a Regional STEMI Protocol – a 12 Year Perspective

Background

The Vancouver Coastal Health (VCH) ST-elevation myocardial infarction (STEMI) program aimed to increase access to primary percutaneous coronary intervention (PPCI) and reduce first-medical-contact-to-device times (FMC-DTs). We evaluated the long-term program impact on PPCI access and FMC-DT, and overall and reperfusion-specific in-hospital mortality.

Methods

We analyzed all VCH STEMI patients between June 2007 and November 2019. The primary outcome was the proportion of patients receiving PPCI over 4 program implementation phases over 12 years. We also evaluated overall changes in median FMC-DT and the proportion of patients achieving guideline-mandated FMC-DT, in addition to overall and reperfusion-specific in-hospital mortality.

Results

A total of 3138 of 4305 VCH STEMI patients were treated with PPCI. PPCI rates increased from 40.2% to 78.7% from 2007 to 2019 (P < 0.001). From phase 1 to 4, median FMC-DT improved from 118 to 93 minutes (percutaneous coronary intervention [PCI]-capable hospitals, P < 0.001) and from 174 to 118 minutes (non-PCI-capable hospitals, P < 0.001), with a concomitant increase in those achieving guideline-mandated FMC-DT (35.5% to 66.1%, P < 0.001). Overall in-hospital mortality was 9.0% (P = 0.20 across phases), with mortality differing significantly by reperfusion strategy (4.0% fibrinolysis, 5.7% PPCI, 30.6% no reperfusion therapy, P < 0.001). Mortality significantly decreased from phase 1 to phase 4 at non-PCI-capable centres (9.6% to 3.9%, P = 0.022) but not at PCI-capable centres (8.7% vs 9.9%, P = 0.27).

Conclusions

A regional STEMI program increased the proportion of patients who received PPCI and improved reperfusion times over 12 years. Although no statistically significant decrease occurred in overall regional mortality incidence, mortality incidence was decreased for patients presenting to non-PCI-capable centres.

The Telecardiology Revolution: From Emergency Management to Daily Clinical Practice

AIMS

Telecardiology is one of the most widespread applications of telemedicine. We aimed to report the design and development of a telecardiology system in the sanitary district of Cosenza, one of the largest in Italy, with a complex orography, and healthcare reorganization needs, for the management of the emergency network and daily clinical practice.

METHODS

Our telecardiology network connects 8 hospitals, 9 first aid centers, 20 local 118-EMS stations, 1 helicopter station, 8 hospital emergency departments, 59 hospital departments, and 3 catheterization laboratories. All data are centralized on a dedicated server, accessible from any location for real-time assessment. The quality, source, and timing of the electrocardiograms transmitted were evaluated.

RESULTS

From October 2015 to December 2019, a total of 389,970 ECGs were transmitted. The quality of ECGs was optimal in 52%, acceptable in 42%, and poor in 6% of the cases. The number of poor-quality ECGs was only 3% in the last 2 years. Out of the total, 145,097 (37.2%) were transmitted from the emergency departments and 5318 (1.4%) from the 118-EMS. Of interest, a sizable part of the ECG was related to routine clinical practice, comprising 110,556 (28.3%) from the cardiology department and 79,256 (20.3%) from other noncardiovascular departments. Finally, the average reporting time was significantly decreased compared to reporting times without a telecardiology system (5-10 vs. 45-90 min).

CONCLUSION

Our telecardiology system provides efficient cardiology assistance for all types, settings, and phases of cardiovascular diseases.

Predictors of hospital prenotification for STEMI and association of prenotification with outcomes

BACKGROUND

Delay to reperfusion in ST-elevation myocardial infarction (STEMI) is detrimental, but can be minimised with prehospital notification by ambulance to the treating hospital. We aimed to assess whether prenotification was associated with improved first medical contact to balloon times (FMC-BT) and whether this resulted in better clinical outcomes. We also aimed to identify factors associated with use of prenotification.

METHODS

This was a retrospective study of prospective Victorian Cardiac Outcomes Registry data for patients undergoing primary percutaneous coronary intervention for STEMI from 2013-2018. Postcardiac arrest were excluded. Patients were grouped by whether they arrived by ambulance with prenotification (group 1), arrived by ambulance without prenotification (group 2) or self-presented (group 3). We compared groups by FMC-BT, incidence of major adverse cardiac and cerebrovascular events (MACCE), mortality and factors associated with the use of prenotification.

RESULTS

2891 patients were in group 1 (79.3% male), 1620 in group 2 (75.7% male) and 1220 in group 3 (82.9% male). Patients who had prenotification were more likely to present in-hours (p=0.004) and self-presenters had lowest rates of cardiogenic shock (p<0.001). Prenotification had shorter FMC-BT than without prenotification (104 min vs 132 min, p<0.001) Self-presenters had superior clinical outcomes, with no difference between ambulance groups. Groups 1 and 2 had similar 30-day MACCE outcomes (7.4% group 1 vs 9.1% group 2, p=0.05) and similar mortality (4.6% group 1 vs 5.9% group 2, p=0.07). In multivariable analysis, male gender, right coronary artery culprit and in-hours presentation independently predicted use of prenotification (all p<0.05).

CONCLUSION

Differences in clinical characteristics, particularly gender, time of presentation and culprit vessel may influence ambulance prenotification. Ambulance cohorts have high-risk features and worse outcomes compared with self-presenters. Improving system inequality in prehospital STEMI diagnosis is recommended for fastest STEMI treatment.

Impact of Pre-Hospital Activation of STEMI on False Positive Activation Rate and Door to Balloon Time

BACKGROUND

Pre-hospital identification of ST-segment elevation myocardial infarction (STEMI) by paramedical staff reduces reperfusion time. However, the impact of this approach on the rate of unnecessary activation of coronary catheterisation lab (CCL) remains unclear.

METHODS

The study reviewed consecutive STEMI patients over 3 years (July 2015 to June 2018) from all primary percutaneous coronary intervention (PPCI) centres and inter-hospital transfers (IHT) from non-PPCI capable centres in Western Australia. Out-of-hospital cardiac arrests (OOHCA) and STEMI calls for in-patients receiving treatment for other medical reasons were excluded.

RESULTS

During the 3 years study period, 1,736 STEMI cases were recorded. Pre-hospital (PH) activation occurred in 799 (46%) cases. Median door to balloon time (D2BT) was 68 minutes (IQR 63 mins). D2BT for PH activation (40 min [IQR 25 min]) was significantly lower than both the PPCI centre emergency department (ED) activation (86 min [IQR 55 min]) and IHT activation groups (108 min [IQR 55 min]), p-value <0.00001. In PH activation group 98% patients received primary PCI in less than 90 minutes compared to 54% and 26% patients in the ED and the IHT activation groups, respectively. False positive STEMI activation rate was lower in the PH activation group (2.75%) compared to ED activation (5.4%) and IHT group (6%), p-value 0.0115. The false positive rate did not vary significantly between working hours and out-of-hour calls (5% vs 4%, p-value=0.304). Pericarditis, coronary artery disease other than STEMI, atypical chest pain, and stress induced cardiomyopathy were the common diagnoses in false positive activations.

CONCLUSION

Pre-hospital activation of STEMI leads to reduced door to balloon times without a significant increase in inappropriate procedures, though false positive activation rates are unclear. The majority of STEMI patients transferred from non-PPCI centres failed to receive reperfusion therapy within 90 minutes of initial hospital presentation. Further studies are required to assess the benefits of thrombolysis in selected patients in inter-hospital transfer group.

Present and Future Status of Cardiovascular Emergency Care System in Urban Areas of Japan - Importance of Prehospital 12-Lead Electrocardiogram

Acute cardiovascular disease, such as acute myocardial infarction and aortic disease, can lead to a serious life-threatening state within minutes to hours, so early accurate diagnosis, and appropriate treatment without delay are essential. To provide high-quality and timely treatment, 24-h availability of medical staff and cardiologists, as well as a cardiac catheterization laboratory are needed. In Japan, the number of patients with acute cardiovascular disease is increasing with the aging population and westernization of lifestyle; however, workstyle reforms for physicians, including a policy to limit overtime work, have been legislated. Under these conditions, it is necessary to centralize hospitals that treat cardiovascular emergency diseases as high-volume centers and build a patient triage system for allocating patients before hospital arrival. The prehospital 12-lead electrocardiogram (ECG) plays a central role in prehospital diagnosis and triage, and its importance will increase in future. We discuss the current and future state of the cardiovascular emergency medical care system utilizing prehospital 12-lead ECG in urban areas of Japan.

Prehospital Evaluation, ED Management, Transfers, and Management of Inpatient STEMI

ST elevation myocardial infarction diagnoses have reduced in number over the past 10 years; however, associated morbidity and mortality remain high. Societal guidelines focus on early diagnosis and timely access to reperfusion, preferably percutaneous coronary intervention (PCI), with fibrinolytics reserved for those who cannot receive timely PCI. Proposed algorithms recommend emergency department bypass in stable patients with a clear diagnosis to reduced door-to-balloon time. Emergency providers should limit their evaluation, focusing on life-threatening comorbidities, unstable vitals, or contraindications to a catheterization laboratory. In-hospital patients prove diagnostically challenging because they may be unable to express symptoms, and reperfusion strategies can complicate other diagnoses.

The impact of pre-hospital 12-lead electrocardiogram and first contact by cardiologist in patients with ST-elevation myocardial infarction in Kanagawa, Japan

Background pre-hospital 12-lead electrocardiogram (ECG) by emergency medical service (EMS) personnel at the site of first medical contact (FMC) and the physician of first contact both play important roles in managing patients with ST-elevation myocardial infarction (STEMI). However, in Japan, pre-hospital 12-lead ECG is not routinely performed by EMS personnel at the site of FMC and the physician of first contact is not always a cardiologist. Methods from October 2015 to October 2019, 2035 consecutive STEMI patients transported from the field by ambulance were analyzed from the K-ACTIVE registry. Based on the presence (+) or absence (-) of pre-hospital 12-lead ECG / first contact by cardiologist, patients were divided into 4 groups (+/+, +/-, -/+, -/-). Patient characteristics, FMC to door time, door to device time and in-hospital mortality were compared. Results the numbers of patients in each group were as follows (+/+, n = 987; +/-, n = 211; -/+, n = 610; -/-, n = 227). For patient characteristics, there were significant differences in the prevalence of dyslipidemia and the presence of chest pain. The FMC to door time was similar (median value, +/+, 24 min; +/-, 25 min; -/+, 24 min; -/-, 24 min; p = 0.23). The door to device time was the shortest in the +/+ group (median value, +/+, 65 min; +/-, 80 min; -/+, 69 min; -/-, 88 min; p < 0.0001). Crude in-hospital mortality was the highest in the -/- group (+/+, 3.9%; +/-, 2.4%; -/+, 5.8%; -/-, 11.9%; p < 0.0001). After adjustment for age and sex, the adjusted odds ratios for in-hospital mortality were as follows [odds ratio (with 95% confidence interval) +/+, 0.33 [0.19-0.57]; +/-, 0.19 [0.07-0.52]; -/+, 0.49 [0.29-0.86]; -/-, 1 [reference)]. Conclusion pre-hospital 12-lead ECG and the physician of first contact had a significant impact on the door to device time and in-hospital mortality. Continuous efforts should be made to improve acute management of STEMI.

Assessment of quality of care of patients with ST-segment elevation myocardial infarction

Aims:

The 2017 European Society of Cardiology guidelines for the management of ST-elevation myocardial infarction recommended assessing quality of care to establish measurable quality indicators in order to ensure that every ST-elevation myocardial infarction patient receives the best possible care. We investigated the quality indicators of healthcare services in Poland provided to ST-elevation myocardial infarction patients.

Methods and results:

The Polish Registry of Acute Coronary Syndromes is a nationwide, multicentre, prospective study of acute coronary syndrome patients in Poland. For the purpose of assessing quality indicators, we included 8279 patients from the Polish Registry of Acute Coronary Syndromes hospitalised with ST-elevation myocardial infarction in 2018. Four hundred and eight of 8279 patients (4.9%) arrived at percutaneous coronary intervention centre by self-transport, 4791 (57.9%) arrived at percutaneous coronary intervention centre by direct emergency medical system transport, and 2900 (37.2%) were transferred from non-percutaneous coronary intervention facilities. Whilst 95.1% of ST-elevation myocardial infarction patients arriving in the first 12 h received reperfusion therapy, the rates of timely reperfusion were much lower (ranging from 39.4% to 55.0% for various ST-elevation myocardial infarction pathways). The median left ventricular ejection fraction was 46% and was assessed before discharge in 86.0% of patients. Four hundred and eighty-nine of 8279 patients (5.9%) died during hospital stay. Optimal medical therapy is prescribed in 50–85% of patients depending on various clinical settings. Only one in two ST-elevation myocardial infarction patients is enrolled in a cardiac rehabilitation program at discharge. No patient-reported outcomes were recorded in the Polish Registry of Acute Coronary Syndromes.

Conclusions:

The results of this study identified areas of healthcare system that require solid improvement. These include direct transport to percutaneous coronary intervention centre, timely reperfusion, guidelines-based medical therapy (in particular in patients with heart failure), referral to cardiac rehabilitation/secondary prevention programs. Also, there is a need for recording quality indicators associated with patient-reported outcomes.

The effect of prehospital telecardiology on the mortality and morbidity of ST-segment elevated myocardial infarction patients undergoing primary percutaneous coronary intervention: A cross-sectional study

OBJECTIVES

The sooner the primary percutaneous coronary intervention (PPCI) is performed, the better prognosis is expected in patients with acute myocardial infarction. The objective is to evaluate the effect of prehospital triage based on electrocardiogram (ECG) and telecardiology on the mortality and morbidity of ST-segment elevated myocardial infarction (STEMI) patients undergoing PPCI.

METHODS

This cross-sectional study was conducted based on the data extracted from the hospital information system (HIS) of one general hospital, which had the capability of performing PPCI 24 h a day, 7 days a week. All patients with STEMI who undergone PPCI during 1 year, transferred by emergency medical service (EMS) and their data were registered in the HIS were eligible. Besides the baseline characteristics, first medical contact (FMC)-to-balloon time was recorded. Morbidity based on predischarge left ventricular ejection fraction (LVEF) and mortality based on Global Registry of Acute Cardiac Events (GRACE) score were also recorded. Patients who were referred to the hospital by EMS with prehospital ECG and telecardiology were compared with those without prehospital ECG.

RESULTS

Totally, 298 patients with STEMI were enrolled, of whom 183 patients (61.4%) had prehospital ECG (telecardiology), and 115 patients (38.6%) had not. The means of predischarge LVEF of the patients in the first and the second groups were 40.7 ± 10.4 and 40.6 ± 11.2, respectively (P = 0.946). The mean of the probability of 6-month mortality based on GRACE score in the first group was significantly less than that of the second group (P = 0.004). Analyses of multivariable ordinal logistic regression showed that 6-month mortality severity risk in the second group was 1.5 times more than the first group (95% confidence interval 0.8-2.6), although this difference was not statistically significant (P = 0.199).

CONCLUSIONS

It is likely that prehospital telecardiology, with shortening FMC to balloon time result in reducing probability 6-month mortality in STEMI patients who undergone PPCI. However, the process of telecardiology had no effect on predischarge LVEF in the current study.

Reducing Delay to Treatment of ST-Elevation Myocardial Infarction With Software Electrocardiographic Interpretation and Transmission (SCINET)

BACKGROUND

Prehospital diagnosis of ST-elevation myocardial infarction (STEMI) has resulted in improved outcomes. However, many patients still walk in to the emergency department (ED) with STEMI, experiencing delays and worse outcomes. Software electrocardiogram (ECG) diagnosis of STEMI and electronic transmission to a cardiologist may result in improved door-to-device (D2D) times.

METHODS

We retrospectively identified all patients presenting with STEMI from January 2015 to September 2016. Components of delay in D2D, ED variables, and the patients' ECGs were extracted from our regional database. All ECGs performed for suspected myocardial infarction in the region were extracted over the study period. We assessed the accuracy of the software 12SL in diagnosing STEMI, ED contributors to delays in D2D, and the potential reduction in D2D if software diagnosis of STEMI resulted in activation of the cardiac catheterization laboratory.

RESULTS

A total of 379 patients presented to an ED in our region and received primary percutaneous coronary intervention over the study period. In the 143,574 ECGs performed over the study period for suspected STEMI, the overall sensitivity and specificity of 12SL were 90.5% and 99.98%, respectively. We estimated a potential 17-minute reduction in D2D in the 90.5% of patients correctly identified as having STEMI, with a false activation rate of 4%. Female patients and older patients experienced an even larger potential benefit, with 24- and 25-minute reductions in D2D, respectively.

CONCLUSIONS

Patients who walk in to an ED with STEMI experience significant system-related delays in recognition and treatment. Automated software diagnosis of STEMI is accurate and could result in significant improvements in D2D times.

Use and impact of the prehospital 12-lead ECG in the primary PCI era (PHECG2): protocol for a mixed-method study

Introduction

Use of the prehospital 12-lead ECG (PHECG) is recommended in patients presenting to emergency medical services (EMS) with suspected acute coronary syndrome (ACS). Prior research found that although PHECG use was associated with improved 30-day survival, a third of patients (typically women, the elderly and those with comorbidities) under EMS care did not receive a PHECG.

The overall aim of the PHECG2 study is to update evidence on care and outcomes for patients eligible for PHECG, specifically addressing the following research questions: (1) Is there a difference in 30-day mortality, and in reperfusion rate, between those who do and those who do not receive PHECG? (2) Has the proportion of eligible patients who receive PHECG changed since the introduction of primary percutaneous coronary intervention networks? (3) Are patients that receive PHECG different from those that do not in terms of social and demographic factors, or prehospital clinical presentation? (4) What factors influence EMS clinicians’ decisions to perform PHECG?

Methods and analysis

This is an explanatory, mixed-method study comprising four work packages (WPs). WP1 is a population-based, linked-data analysis of a national ACS registry (Myocardial Ischaemia National Audit Project). WP2 is a retrospective chart review of patient records from three large regional EMS. WP3 comprises focus groups of EMS personnel. WP4 will synthesise findings from WP1–3 to inform the development of an intervention to increase PHECG uptake.

Ethics and dissemination

The study has been approved by the London-Hampstead Research Ethics Committee (ref: 18LO1679). Findings will be disseminated through feedback to participating EMS, conference presentations and publication in peer-reviewed journals.

Trial registration number

NCT03699137

Dopamine and cAMP-regulated phosphoprotein 32 kDa (DARPP-32) and survival in breast cancer: a retrospective analysis of protein and mRNA expression

Dopamine and cAMP regulated phosphoprotein 32 kDa (DARPP-32) also known as phosphoprotein phosphatase-1 regulatory subunit 1B and encoded by the PPP1R1B gene is an inhibitor of protein phosphatase-1 and protein kinase A. DARPP-32 is expressed in a wide range of epithelial cells and some solid tumours; however, its role in breast cancer is only partially defined. DARPP-32 expression was determined using immunohistochemistry in two independent cohorts of early stage invasive breast cancer patients (discovery n = 1352; validation n = 1655), and 112 HER2 positive breast cancer patients treated with trastuzumab and adjuvant chemotherapy. PPP1R1B mRNA expression was assessed in the METABRIC cohort (n = 1980), using artificial neural network analysis to identify associated genes. In the discovery cohort, low nuclear expression of DARPP-32 was significantly associated with shorter survival (P = 0.041), which was independent of other prognostic variables (P = 0.019). In the validation cohort, low cytoplasmic and nuclear expression was significantly associated with shorter survival (both P = 0.002), with cytoplasmic expression independent of other prognostic variables (P = 0.023). Stronger associations with survival in oestrogen receptor (ER) positive disease were observed. In patients treated with trastuzumab, low nuclear expression was significantly associated with adverse progression-free survival (P = 0.031). In the METABRIC cohort, low PPP1R1B expression was associated with shortened survival of ER positive patients. Expression of CDC42 and GRB7, amongst others, were associated with PPP1R1B expression. This data suggests a role for DARPP-32 as a prognostic marker with clinical utility in breast cancer.

Cancellation of the Cardiac Catheterization Lab After Activation for ST-Segment-Elevation Myocardial Infarction

BACKGROUND

Prehospital ECG-based cardiac catheterization laboratory (CCL) activation for ST-segment-elevation myocardial infarction reduces door-to-balloon times, but CCL cancellations (CCL^X) remain a challenging problem. We examined the reasons for CCL^X, clinical characteristics, and outcomes of patients presenting as ST-segment-elevation myocardial infarction activations who receive emergent coronary angiography (EA) compared with CCL^X.

METHODS AND RESULTS

We reviewed all consecutive CCL activations between January 1, 2012, and December 31, 2014 (n=1332). Data were analyzed comparing 2 groups stratified as EA (n=466) versus CCL^X (n=866; 65%). Reasons for CCL^X included bundle branch block (21%), poor-quality prehospital ECG (18%), non-ST-segment-elevation myocardial infarction ST changes (18%), repolarization abnormality (13%), and arrhythmia (8%). A multivariate logistic regression model using age, peak troponin, and initial ECG findings had a high discriminatory value for determining EA versus CCL^X (C statistic, 0.985). CCL^X subjects were older and more likely to be women, have prior coronary artery bypass grafting, or a paced rhythm ( P<0.0001 for all). All-cause mortality did not differ between groups at 1 year or during the study period (mean follow-up, 2.186±1.167 years; 15.8% EA versus 16.2% CCL^X; P=0.9377). Cardiac death was higher in the EA group (11.8% versus 3.0%; P<0.0001). After adjusting for clinical variables associated with survival, CCL^X was associated with an increased risk for all-cause mortality during the study period (hazard ratio, 1.82; 95% CI, 1.28-2.59; P=0.0009).

CONCLUSIONS

In this study, prehospital ECG without overreading or transmission lead to frequent CCL^X. CCL^X subjects differ with regard to age, sex, risk factors, and comorbidities. However, CCL^X patients represent a high-risk population, with frequently positive cardiac enzymes and similar short- and long-term mortality compared with EA. Further studies are needed to determine how quality improvement initiatives can lower the rates of CCL^X and influence clinical outcomes.

Paramedic versus physician-staffed ambulances and prehospital delays in the management of patients with ST-segment elevation myocardial infarction

BACKGROUND

Time delays to reperfusion therapy in ST-segment elevation myocardial infarction (STEMI) still remain a considerable drawback in many healthcare systems. Emergency medical service (EMS) has a critical role in the early management of STEMI. Under investigation herein, was whether the use of physician-staffed ambulances leads to shorter pre-hospital delays in STEMI patients.

METHODS

This was an observational and retrospective study, using data from the registry of the Silesian regional EMS system in Katowice, Poland and the Polish Registry on Acute Coronary Syndromes (PL-ACS) for a study period of January 1, 2013 to December 31, 2016. The study population (n = 717) was divided into two groups: group 1 (n = 546 patients) - physician-staffed ambulances and group 2 (n = 171 patients) - paramedic-staffed ambulances.

RESULTS

Responses during the day and night shifts were similar. Paramedic-led ambulances more often transmitted 12-lead electrocardiogram (ECG) to the percutaneous coronary intervention centers. All EMS time intervals were similar in both groups. The type of EMS dispatched to patients (physicianstaffed vs. paramedic/nurse-only staffed ambulance) was adjusted for ECG transmission, sex had no impact on in-hospital mortality (odds ratio [OR] 1.41; 95% confidence interval [CI] 0.79-1.95; p = 0.4). However, service time exceeding 42 min was an independent predictor of in-hospital mortality (OR 4.19; 95% CI 1.27-13.89; p = 0.019). In-hospital mortality rate was higher in the two upper quartiles of service time in the entire study population.

CONCLUSIONS

These findings suggest that both physician-led and paramedic-led ambulances meet the criteria set out by the Polish and European authorities. All EMS time intervals are similar regardless of the type of EMS unit dispatched. A physician being present on board did not have a prognostic impact on outcomes.

Review article: Impact of 12-lead electrocardiography system of care on emergency medical service delays in ST-elevation myocardial infarction: A systematic review and meta-analysis

To assess the impact of prehospital 12-lead electrocardiography (PH ECG) on emergency medical service (EMS) delay in patients with ST-elevation myocardial infarction (STEMI), we systematically searched five online electronic databases, including MEDLINE, Embase, Emcare, Cochrane Library and CINAHL, between 1990 and August 2017. Controlled trials and observational studies comparing EMS time delays with and without PH ECG in STEMI patients were eligible. Two reviewers independently screened studies for eligibility, extracted data and appraised study quality. The primary outcome was the time elapsed between scene arrival and hospital arrival. The secondary outcomes were response time, scene time, transport time and emergency call-to-hospital arrival time. Random effects models were used to pool weighted mean differences in EMS delay. Seven moderate-quality studies (two controlled trials and five observational) involving 81 005 participants were included in the data synthesis. The primary treatment strategy was in-hospital thrombolysis and percutaneous coronary intervention in four and three studies, respectively. PH ECG was associated with a 7.0 min increase in scene arrival-to-hospital arrival time (three studies; n = 80 628; 95% CI 6.7-7.2; I² = 0.0%) and a 2.9 min increase in scene time (four studies; n = 377; 95% CI 1.2-4.6; I² = 0.0%). PH ECG had no effect on transport or call-to-hospital intervals, although both measures showed evidence of heterogeneity. In patients with STEMI, PH ECG is associated with a modest increase in EMS delays. Measurement and improvement of EMS system delays may help to expedite treatment for STEMI.

Sex Differences in Timeliness of Reperfusion in Young Patients With ST-Segment-Elevation Myocardial Infarction by Initial Electrocardiographic Characteristics

BACKGROUND

Young women with ST-segment-elevation myocardial infarction experience reperfusion delays more frequently than men. Our aim was to determine the electrocardiographic correlates of delay in reperfusion in young patients with ST-segment-elevation myocardial infarction.

METHODS AND RESULTS

We examined sex differences in initial electrocardiographic characteristics among 1359 patients with ST-segment-elevation myocardial infarction in a prospective, observational, cohort study (2008-2012) of 3501 patients with acute myocardial infarction, 18 to 55 years of age, as part of the VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study at 103 US and 24 Spanish hospitals enrolling in a 2:1 ratio for women/men. We created a multivariable logistic regression model to assess the relationship between reperfusion delay (door-to-balloon time >90 or >120 minutes for transfer or door-to-needle time >30 minutes) and electrocardiographic characteristics, adjusting for sex, sociodemographic characteristics, and clinical characteristics at presentation. In our study (834 women and 525 men), women were more likely to exceed reperfusion time guidelines than men (42.4% versus 31.5%; P<0.01). In multivariable analyses, female sex persisted as an important factor in exceeding reperfusion guidelines after adjusting for electrocardiographic characteristics (odds ratio, 1.57; 95% CI, 1.15-2.15). Positive voltage criteria for left ventricular hypertrophy and absence of a prehospital ECG were positive predictors of reperfusion delay; and ST elevation in lateral leads was an inverse predictor of reperfusion delay.

CONCLUSIONS

Sex disparities in timeliness to reperfusion in young patients with ST-segment-elevation myocardial infarction persisted, despite adjusting for initial electrocardiographic characteristics. Left ventricular hypertrophy by voltage criteria and absence of prehospital ECG are strongly positively correlated and ST elevation in lateral leads is negatively correlated with reperfusion delay.

Pre-hospital detection of acute ischemic stroke secondary to emergent large vessel occlusion: lessons learned from electrocardiogram and acute myocardial infarction

Currently, there is no device capable of detecting acute ischemic stroke (AIS) secondary to emergent large vessel occlusion (ELVO) in the pre-hospital setting. The inability to reliably identify patients that would benefit from primary treatment with endovascular thrombectomy remains an important limitation to optimizing emergency medical services (EMS) triage models and time-to-treatment. Several clinical grading scales that rely solely on clinical examination have been proposed and have demonstrated only moderate predictive ability for ELVO. Consequently, a technology capable of detecting ELVO in the pre-hospital setting would be of great benefit. An analogous scenario existed decades ago, in which pre-hospital detection of acute myocardial infarction (AMI) was unreliable until the emergence of the 12-lead ECG and its adoption by EMS providers. This review details the implementation of pre-hospital ECG (PHECG) for the detection of AMI and explores how early experience with PHECG may be applied to ELVO detection devices, once they become available.

Call-to-balloon time dashboard in patients with ST-segment elevation myocardial infarction results in significant improvement in the logistic chain

AIMS

Timely reperfusion with primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI) patients is associated with superior clinical outcomes. Aiming to reduce ischaemic time, an innovative system for home-to-hospital (H2H) time monitoring was implemented, which enabled real-time evaluation of ischaemic time intervals, regular feedback and improvements in the logistic chain. The objective of this study was to assess the results after implementation of the H2H dashboard for monitoring and evaluation of ischaemic time in STEMI patients.

METHODS AND RESULTS

Ischaemic time in STEMI patients transported by emergency medical services (EMS) and treated with pPCI in the Noordwest Ziekenhuis, Alkmaar before (2008-2009; n=495) and after the implementation of the H2H dashboard (2011-2014; n=441) was compared. Median time intervals were significantly shorter in the H2H group (door-to-balloon time 32 [IQR 25-43] vs. 40 [IQR 28-55] minutes, p-value <0.001, FMC-to-balloon time 62 [IQR 52-75] vs. 80 [IQR 67-103] minutes, p-value <0.001, and treatment delay 142 [IQR 103-221] vs. 159 [IQR 123-253] minutes, p-value <0.001). The H2H time dashboard was independently associated with shorter time delays.

CONCLUSIONS

Real-time monitoring and feedback on time delay with the H2H dashboard improves the logistic chain in STEMI patients, resulting in shorter ischaemic time intervals.

Implementation of Regional ST-Segment Elevation Myocardial Infarction Systems of Care: Successes and Challenges

Current guidelines recommend that communities create and maintain a regional system of ST-segment elevation myocardial infarction (STEMI) care that includes assessment and continuous quality improvement of emergency medical services and hospital-based activities. Availability and timely access is a challenge in many areas of the United States. This article reviews clinical trial data supporting the use of primary percutaneous coronary intervention as the optimal reperfusion strategy, and fibrinolysis as an option when this is not possible. It then describes the outcomes and benefits of implementing regional systems of STEMI care, and discusses ongoing challenges for STEMI system implementation, including inadequate data collection and feedback, and hospital and physician competition.

False Activations for ST-Segment Elevation Myocardial Infarction

First-medical-contact-to-device (FMC2D) times have improved over the past decade, as have clinical outcomes for patients presenting with ST-elevation myocardial infarction (STEMI). However, with improvements in FMC2D times, false activation of the cardiac catheterization laboratory (CCL) has become a challenging problem. The authors define false activation as any patient who does not warrant emergent coronary angiography for STEMI. In addition to clinical outcome measures for these patients, STEMI systems should collect data regarding the total number of CCL activations, the total number of emergency coronary angiograms, and the number revascularization procedures performed.

Time to Treatment: Focus on Transfer in ST-Elevation Myocardial Infarction

In the modern ST-elevation myocardial infarction (STEMI) system, the use of electrocardiogram by emergency medical services (EMS) personnel and the option to bypass emergency departments on route to a PCI-capable hospital is of particular importance. Through training and a standardized referral process, EMS personnel can now accurately diagnose and refer STEMI patients directly to the catheterization laboratory of a percutaneous coronary intervention-capable hospital. Regional STEMI models have been implemented successfully across North America, resulting in palpable reductions in door-to-balloon time, morbidity, and mortality.

ANMCO/SIT Consensus Document: telemedicine for cardiovascular emergency networks

Telemedicine has deeply innovated the field of emergency cardiology, particularly the treatment of acute myocardial infarction. The ability to record an ECG in the early prehospital phase, thus avoiding any delay in diagnosing myocardial infarction with direct transfer to the cath-lab for primary angioplasty, has proven to significantly reduce treatment times and mortality. This consensus document aims to analyse the available evidence and organizational models based on a support by telemedicine, focusing on technical requirements, education, and legal aspects.

Pre-hospital electrocardiogram triage with telemedicine near halves time to treatment in STEMI: A meta-analysis and meta-regression analysis of non-randomized studies

BACKGROUND

A shorter time to treatment has been shown to be associated with lower mortality rates in acute myocardial infarction (AMI). Several strategies have been adopted with the aim to reduce any delay in diagnosis of AMI: pre-hospital triage with telemedicine is one of such strategies. We therefore aimed to measure the real effect of pre-hospital triage with telemedicine in case of AMI in a meta-analysis study.

METHODS

We performed a meta-analysis of non-randomized studies with the aim to quantify the exact reduction of time to treatment achieved by pre-hospital triage with telemedicine. Data were pooled and compared by relative time reduction and 95% C.I.s. A meta-regression analysis was performed in order to find possible predictors of shorter time to treatment.

RESULTS

Eleven studies were selected and finally evaluated in the study. The overall relative reduction of time to treatment with pre-hospital triage and telemedicine was -38/-40% (p<0.001). Absolute time reduction was significantly correlated to time to treatment in the control groups (p<0.001), while relative time reduction was independent. A non-significant trend toward shorter relative time reductions was observed over years.

CONCLUSIONS

Pre-hospital triage with telemedicine is associated with a near halved time to treatment in AMI. The benefit is larger in terms of absolute time to treatment reduction in populations with larger delays to treatment.

The Emergency Medical Care of Patients With Acute Myocardial Infarction

BACKGROUND

Optimizing the emergency medical care chain might shorten the time to treatment of patients with ST-elevation myocardial infarction (STEMI). The initial care by a physician, and, in particular, correct ECG interpretation, are critically important factors.

METHODS

From 1999 onward, data on the care of patients with myocardial infarction have been recorded and analyzed in the Berlin Myocardial Infarction Registry. In the First Medical Contact Study, data on initial emergency medical care were obtained on 1038 patients who had been initially treated by emergency physicians in 2012. Their pre-hospital ECGs were re-evaluated in a blinded fashion according to the criteria of the European Society of Cardiology.

RESULTS

The retrospective re-evaluation of pre-hospital ECGs revealed that 756 of the 1038 patients had sustained a STEMI. The emergency physicians had correctly diagnosed STEMI in 472 patients (62.4%), and they had correctly diagnosed ventricular fibrillation in 85 patients (11.2%); in 199 patients (26.3%), the ECG interpretation was unclear. The pre-hospital ECG interpretation was significantly associated with the site of initial hospitalization and the ensuing times to treatment. In particular, the time from hospital admission to cardiac catheterization was longer in patients with an unclear initial ECG interpretation than in those with correctly diagnosed STEMI (121 [54; 705] vs. 36 [19; 60] minutes, p <0.001). After multivariate adjustment, this corresponded to a hazard ratio* of 2.67 [2.21; 3.24].

CONCLUSION

Pre-hospital ECG interpretation in patients with STEMI was a trigger factor with a major influence on the time to treatment in the hospital. The considerable percentage of pre-hospital ECGs whose interpretation was unclear implies that there is much room for improvement.

Decade-long trends in the timeliness of receipt of a primary percutaneous coronary intervention

Objectives

The purpose of this study was to examine decade-long trends (2001–2011) in, and factors associated with, door-to-balloon time within 90 minutes of hospital presentation among patients hospitalized with ST-segment elevation myocardial infarction (STEMI) who received a primary percutaneous coronary intervention (PCI).

Methods

Residents of central Massachusetts hospitalized with STEMI who received a primary PCI at two major PCI-capable medical centers in central Massachusetts on a biennial basis between 2001 and 2011 comprised the study population (n=629). Multivariable regression analyses were used to examine factors associated with failing to receive a primary PCI within 90 minutes after emergency department (ED) arrival.

Results

The average age of this patient population was 61.9 years; 30.5% were women, and 91.7% were White. During the years under study, 50.9% of patients received a primary PCI within 90 minutes of ED arrival; this proportion increased from 2001/2003 (17.2%) to 2009/2011 (70.5%) (P<0.001). Having previously undergone coronary artery bypass graft surgery, arriving at the ED by car/walk-in and during off-hours were significantly associated with a higher risk of failing to receive a primary PCI within 90 minutes of ED arrival.

Conclusion

The likelihood of receiving a timely primary PCI in residents of central Massachusetts hospitalized with STEMI at the major teaching/community medical centers increased dramatically during the years under study. Several groups were identified for purposes of heightened surveillance and intervention efforts to reduce the likelihood of failing to receive a timely primary PCI among patients acutely diagnosed with STEMI.

Clinical management and hospital outcomes of acute coronary syndrome patients in Mexico: The Third National Registry of Acute Coronary Syndromes (RENASICA III)

OBJECTIVE

To describe current management and clinical outcomes in patients hospitalized with an acute coronary syndrome (ACS) in Mexico.

METHODS

RENASICA III was a prospective multicenter registry of consecutive patients hospitalized with an ACS. Patients had objective evidence of ischemic heart disease; those with type II infarction or secondary ischemic were excluded. Study design conformed to current quality recommendations.

RESULTS

A total of 123 investigators at 29 tertiary and 44 community hospitals enrolled 8296 patients with an ACS (4038 with non-ST-elevation myocardial infarction/unstable angina [NSTEMI/UA], 4258 with ST-elevation myocardial infarction [STEMI]). The majority were younger (62±12years) and 76.0% were male. On admission 80.5% had ischemic chest pain lasting >20min and clinical stability. Left ventricular dysfunction was more frequent in NSTEMI/UA than in those with STEMI (30.0% vs. 10.7%, p<0.0001). In STEMI 37.6% received thrombolysis and 15.0% primary PCI. PCI was performed in 39.6% of NSTEMI/UA (early strategy in 10.8%, urgent strategy in 3.0%). Overall hospital death rate was 6.4% (8.7% in STEMI vs. 3.9% in NSTEMI/UA, p<0.001). The strongest independent predictors of hospital mortality were cardiogenic shock (odds ratio 22.4, 95% confidence interval 18.3-27.3) and ventricular fibrillation (odds ratio 12.5, 95% confidence interval 9.3-16.7).

CONCLUSION

The results from RENASICA III establish the urgent need to develop large-scale regional programs to improve adherence to guideline recommendations in ACS, including rates of pharmacological thrombolysis and increasing the ratio of PCI to thrombolysis.

Field triage to primary percutaneous coronary intervention: Factors influencing health-related quality of life for patients aged ≥70 and <70 years with non-complicated ST-elevation myocardial infarction

OBJECTIVE

To examine clinical and health-related quality of life (HRQOL) outcomes and predictors of HRQOL for uncomplicated field triage ST-elevation myocardial infarction (STEMI) patients aged ≥70 years and <70 years after primary percutaneous coronary intervention (PPCI).

BACKGROUND

Pre-hospital field triage for PPCI is associated with lower mortality but the impact of age and other factors on HRQOL remains unknown.

METHODS

77 field triage STEMI patients were assessed for HRQOL using the Short Form-12 (SF-12) and the Seattle Angina Questionnaire (SAQ) at 4 weeks and 6 months after PPCI.

RESULTS

Regression analysis showed improvements in SF-12 domains and angina stability for older people. Age predicted lower physical function (p = 0.001) and better SAQ QOL at 6 months (p = 0.003).

CONCLUSION

Age, length of hospitalization, recurrent angina and hypertension were important predictors of HRQOL with PPCI. Assessment of HRQOL combined with increased support for physical and emotional recovery is needed to improve clinical care for field triage PPCI patients.

Prehospital triage and direct transport of patients with ST-elevation myocardial infarction to primary percutaneous coronary intervention centres: a systematic review and meta-analysis

Objective:

Percutaneous coronary intervention (PCI) appears to be superior to in-hospital fibrinolysis for most patients with ST-elevation myocardial infarction (STEMI). However, few hospitals have PCI capability. The optimal prehospital strategy for facilitating rapid coronary reperfusion in STEMI patients is unclear. We sought to determine whether direct transport of adult STEMI patients by emergency medical services to primary PCI centres improves 30-day all-cause mortality when compared with a strategy of transportation to the closest hospital.

Methods:

We systematically searched MEDLINE, EMBASE, Cochrane “CENTRAL” database (1980-July 2007) and several other electronic databases. Two authors independently assessed citations for relevance. Two authors independently abstracted data from included studies. We included studies that, 1) transported patients directly to a PCI-capable centre for primary PCI, 2) had a control group that was transported to the closest hospital and 3) reported outcomes of treatment time intervals, all-cause mortality, reinfarction rate, stroke rate or the frequency of cardiogenic shock. We used a random effects model to provide pooled estimates of relative risk (RR) when data allowed.

Results:

We identified 2264 citations with the search. Five studies, including 980 STEMI patients, met inclusion criteria, and were clinically heterogeneous and of variable quality. Most studies were European (3/5) and involved physician out-of-hospital care providers. There was a trend toward increased survival with direct transport to primary PCI but this was not statistically significant (RR 0.51, 95% confidence interval [CI] 0.24–1.10). One study reported nonsignificant reductions in reinfarction (RR 0.43, 95% CI 0.11–1.60) and stroke (RR 0.33, 95% CI 0.01–8.06) with direct transport for primary PCI.

Conclusion:

There is insufficient evidence to support the effectiveness of direct transport of patients with STEMI for primary PCI when compared with transportation to the closest hospital.

Pre-hospital versus in-hospital thrombolysis for ST-elevation myocardial infarction

BACKGROUND

Early thrombolysis for individuals experiencing a myocardial infarction is associated with better mortality and morbidity outcomes. While traditionally thrombolysis is given in hospital, pre-hospital thrombolysis is proposed as an effective intervention to save time and reduce mortality and morbidity in individuals with ST-elevation myocardial infarction (STEMI). Despite some evidence that pre-hospital thrombolysis may be delivered safely, there is a paucity of controlled trial data to indicate whether the timing of delivery can be effective in reducing key clinical outcomes.

OBJECTIVES

To assess the morbidity and mortality of pre-hospital versus in-hospital thrombolysis for STEMI.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (OVID), EMBASE (OVID), two citation indexes on Web of Science (Thomson Reuters) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) for randomised controlled trials and grey literature published up to June 2014. We also searched the reference lists of articles identified, clinical trial registries and unpublished thesis sources. We did not contact pharmaceutical companies for any relevant published or unpublished articles. We applied no language, date or publication restrictions. The Cochrane Heart Group conducted the primary electronic search.

SELECTION CRITERIA

We included randomised controlled trials of pre-hospital versus in-hospital thrombolysis in adults with ST-elevation myocardial infarction diagnosed by a healthcare provider.

DATA COLLECTION AND ANALYSIS

Two authors independently screened eligible studies for inclusion and carried out data extraction and 'Risk of bias' assessments, resolving any disagreement by consulting a third author. We contacted authors of potentially suitable studies if we required missing or additional information. We collected efficacy and adverse effect data from the trials.

MAIN RESULTS

We included three trials involving 538 participants. We found low quality of evidence indicating uncertainty whether pre-hopsital thrombolysis reduces all-cause mortality in individuals with STEMI compared to in-hospital thrombolysis (risk ratio 0.73, 95% confidence interval 0.37 to 1.41). We found high-quality evidence (two trials, 438 participants) that pre-hospital thrombolysis reduced the time to receipt of thrombolytic treatment compared with in-hospital thrombolysis. For adverse events, we found moderate-quality evidence that the occurrence of bleeding events was similar between participants receiving in-hospital or pre-hospital thrombolysis (two trials, 438 participants), and low-quality evidence that the occurrence of ventricular fibrillation (two trials, 178 participants), stroke (one trial, 78 participants) and allergic reactions (one trial, 100 participants) was also similar between participants receiving in-hospital or pre-hospital thrombolysis. We considered the included studies to have an overall unclear/high risk of bias.

AUTHORS' CONCLUSIONS

Pre-hospital thrombolysis reduces time to treatment, based on studies conducted in higher income countries. In settings where it can be safely and correctly administered by trained staff, pre-hospital thrombolysis may be an appropriate intervention. Pre-hospital thrombolysis has the potential to reduce the burden of STEMI in lower- and middle-income countries, especially in individuals who have limited access to in-hospital thrombolysis or percutaneous coronary interventions. We found no randomised controlled trials evaluating the efficacy of pre-hospital thrombolysis for STEMI in lower- and middle-income countries. Large high-quality multicentre randomised controlled trials implemented in resource-constrained countries will provide additional evidence for the efficacy and safety of this intervention. Local policy makers should consider their local health infrastructure and population distribution needs. These considerations should be taken into account when developing clinical guidelines for pre-hospital thrombolysis.

Real-time, two-way interaction during ST-segment elevation myocardial infarction management improves door-to-balloon times

OBJECTIVES

The study aimed to determine if utilization of the CodeHeart application (CHap) reduces door-to-balloon (DTB) times of ST-segment elevation myocardial infarction (STEMI) patients.

BACKGROUND

A pre-hospital electrocardiogram improves the management of patients with STEMI. Current telecommunication systems do not permit real-time interaction with the initial care providers. Our institution developed a novel telecommunications system based on a software application that permits real-time, two-way video and voice interaction over a secured network.

METHODS

All STEMI system activations after implementation of the CHap were prospectively entered into a database. Consecutive CHap activations were compared to routine activations as controls, during the same time period.

RESULTS

A total of 470 STEMI system activations occurred; CHap was used in 83 cases (17.7%). DTB time was reduced by the use of CHap when compared to controls (CHap 103 minutes, 95% CI [87.0-118.3] vs. standard 149 minutes, 95% CI [134.0-164.8], p<0.0001), as was first call-to-balloon time (CHap 70 minutes, 95% CI [60.8-79.5] vs. standard 92 minutes, 95% CI [85.8-98.9], p=0.0002). The percentage of 'true positive' catheterization laboratory activations was nominally higher with the use of CHap, although this did not reach statistical significance [CHap 47/83 (56.6%) vs. routine 178/387 (45.9%), p=0.103].

CONCLUSION

The implementation of a two-way telecommunications system allowing real-time interactions between interventional cardiologists and referring practitioners improves overall DTB time. In addition, it has the potential to decrease the frequency of false activations, thereby improving the cost efficiency of a network's STEMI system.

Association between prehospital electrocardiogram use and patient home distance from the percutaneous coronary intervention center on total reperfusion time in ST-segment-elevation myocardial infarction patients: a retrospective analysis from the national cardiovascular data registry

BACKGROUND

Current guidelines recommend ≤90 minutes from first medical contact to percutaneous coronary intervention (FMC2B) for ST-segment-elevation myocardial infarction (STEMI) patients. We evaluated the relationship between patient home distance from a percutaneous coronary intervention (PCI) center, prehospital electrocardiogram (ECG) use, and FMC2B time among patients with STEMI.

METHODS

We performed a retrospective cohort study including all STEMI patients in the ACTION-Get With The Guidelines registry from July 1, 2008, to September 30, 2012, who were transported by ambulance to a PCI center. Patient home distance was defined as the driving distance from the patient's home zip code to the PCI center address. Distance was classified into tertiles, and linear regression was used to characterize the interaction between prehospital ECG use and patient home distance with respect to FMC2B time.

RESULTS

Of the 29,506 STEMI patients, 19,690 (67%) received a prehospital ECG. The median patient home distance to the PCI center was 11.0 miles among patients with and 9.9 miles among those without a prehospital ECG. Prehospital ECGs were associated with a 10-minute reduction in the FMC2B time (P < .0001), which was consistent across distance tertiles (11 vs 11 vs 10 minutes). The association between prehospital ECGs and shorter FMC2B was attenuated by 0.8 minute for every 10-mile increase in distance (interaction P = .0002).

CONCLUSIONS

Prehospital ECGs are associated with a 10-minute reduction in the FMC2B time. However, patient home distance from a PCI center does not substantially change this association.

Effects of prehospital 12-lead ECG on processes of care and mortality in acute coronary syndrome: a linked cohort study from the Myocardial Ischaemia National Audit Project

OBJECTIVE

To describe patterns of prehospital ECG (PHECG) use and determine its association with processes and outcomes of care in patients with ST-elevation myocardial infarction (STEMI) and non-STEMI.

METHODS

Population-based linked cohort study of a national myocardial infarction registry.

RESULTS

288 990 patients were admitted to hospitals via emergency medical services (EMS) between 1 January 2005 and 31 December 2009. PHECG use increased overall (51% vs 64%, adjusted OR (aOR) 2.17, 95% CI 2.12 to 2.22), and in STEMI (64% vs 79%, aOR 2.34, 95% CI 2.25 to 2.44). Patients who received PHECG were younger (71 years vs 74 years, P<0.0001); and less likely to be female (33.1% vs 40.3%, OR 0.87, 95% CI 0.86 to 0.89), or to have comorbidities than those who did not. For STEMI, reperfusion was more frequent in those having PHECG (83.5% vs 74.4%, p<0.0001). PHECG was associated with more primary percutaneous coronary intervention patients achieving call-to-balloon time <90 min (27.9% vs 21.4%, aOR 1.38, 95% CI 1.24 to 1.54) and more patients who received fibrinolytic therapy achieving door-to-needle time <30 min (90.6% vs 83.7%, aOR 2.13, 95% CI 1.91 to 2.38). Patients with PHECG exhibited significantly lower 30-day mortality rates than those who did not (7.4% vs 8.2%, aOR 0.94, 95% CI 0.91 to 0.96).

CONCLUSIONS

Findings from this national MI registry demonstrate a survival advantage in STEMI and non-STEMI patients when PHECG was used.