Use of emergency medical services in acute myocardial infarction and subsequent quality of care: observations from the National Registry of Myocardial Infarction 2

Use of emergency medical service transport among patients with ST-segment-elevation myocardial infarction: findings from the National Cardiovascular Data Registry Acute Coronary Treatment Intervention Outcomes Network Registry-Get With The Guidelines

BACKGROUND

Activation of emergency medical services (EMS) is critical for the early triage and treatment of patients experiencing ST-segment-elevation myocardial infarction, yet data regarding EMS use and its association with subsequent clinical care are limited.

METHODS AND RESULTS

We performed an observational analysis of 37 634 ST-segment-elevation myocardial infarction patients treated at 372 US hospitals participating in the National Cardiovascular Data Registry Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines between January 2007 and September 2009, and examined independent patient factors associated with EMS transportation versus patient self-transportation. We found that EMS transport was used in only 60% of ST-segment-elevation myocardial infarction patients. Older patients, those living farther from the hospital, and those with hemodynamic compromise were more likely to use EMS transport. In contrast, race, income, and education level did not appear to be associated with the mode of transport. Compared with self-transported patients, EMS-transported patients had significantly shorter delays in both symptom-onset-to-arrival time (median, 89 versus 120 minutes; P<0.0001) and door-to-reperfusion time (median door-to-balloon time, 63 versus 76 minutes; P<0.0001; median door-to-needle time, 23 versus 29 minutes; P<0.0001).

CONCLUSIONS

Emergency medical services transportation to the hospital is underused among contemporary ST-segment-elevation myocardial infarction patients. Nevertheless, use of EMS transportation is associated with substantial reductions in ischemic time and treatment delays. Community education efforts are needed to improve the use of emergency transport as part of system-wide strategies to improve ST-segment-elevation myocardial infarction reperfusion care.

Differences in admitting hospital characteristics for black and white Medicare beneficiaries with acute myocardial infarction

BACKGROUND

Racial disparities in acute myocardial infarction treatment may be due to differences in admitting hospitals. Little is known about factors associated with hospital selection for black and white acute myocardial infarction patients.

METHODS AND RESULTS

We identified black and white Medicare beneficiaries with acute myocardial infarction in 63 hospital referral regions with at least 50 black admissions during 2005 (n=65,633). We calculated distance from patient home to hospital referral region hospitals using ZIP code centroids. We assessed hospital quality using a composite score made up of hospital risk-adjusted 30-day mortality and acute myocardial infarction performance measures. Hospitals with a score in the top 20% were categorized as high quality, and those in the lowest 20% as low quality. We used conditional multinomial logit models to examine differences in hospital selection for blacks and whites. On average, blacks lived closer to revascularization hospitals (mean, 3.8 versus 6.8 miles; P<0.001) and to high-quality hospitals (mean, 5.6 versus 9.7 miles; P<0.001). After distance was accounted for, blacks were relatively less likely (P<0.001) to be admitted to revascularization hospitals (risk ratio [RR], 0.87; 95% confidence interval [CI], 0.80 to 0.95) and to high-quality hospitals (RR, 0.88; 95% CI, 0.801 to 0.95) but more likely (P<0.001) to be admitted to low-quality hospitals (RR, 1.17; 95% CI, 1.05 to 1.29). In analyses matched by home ZIP code, differences in admissions to revascularization (RR, 0.92; 95% CI, 0.80 to 1.05), high-quality (RR, 0.94; 95% CI, 0.81 to 1.07), and low-quality (RR, 1.15; 95% CI, 0.94 to 1.35) hospitals were not significant.

CONCLUSIONS

Differences in admissions to revascularization and high-quality hospitals may contribute to disparities in acute myocardial infarction care. These differences may be due in part to residential ZIP code characteristics.

Transfer travel times for primary percutaneous coronary intervention from low-volume and non-percutaneous coronary intervention-capable hospitals to high-volume centers in Florida

STUDY OBJECTIVE

Current guidelines recommend that ST-elevation myocardial infarction (STEMI) patients receive percutaneous coronary intervention less than or equal to 90 minutes from first medical contact, preferably at high-volume percutaneous coronary intervention centers (≥400 percutaneous coronary interventions annually). Because many patients present to low-volume or non-percutaneous coronary intervention-capable STEMI referral hospitals, timely percutaneous coronary intervention treatment requires effective transfer systems, which include interfacility transport times of less than 30 minutes. We investigate the geographic feasibility of achieving timely interfacility transport from STEMI referral hospitals to percutaneous coronary intervention hospitals in Florida.

METHODS

Using 2006 Florida hospital discharge data, we calculated driving times between STEMI referral hospitals and the nearest medium-/high-volume percutaneous coronary intervention centers. We plotted transfer travel time cumulative proportion survival curves for hospitals and patients to assess the feasibility of transfer within 30 minutes to higher-volume facilities. Differences by geographic location (rural versus urban) and patient race/ethnicity were examined.

RESULTS

In 2006, 77% of STEMI referral hospitals had transfer travel times within 30 minutes; 90th percentile for interhospital driving time was 56 minutes. For patients at STEMI referral hospitals, 85.6% were at facilities within a 30-minute drive of a high-/medium-volume percutaneous coronary intervention center; 90th percentile was 31 minutes. We found marked rural/urban disparities, with longer average driving times for patients in rural and small metropolitan counties. Significant racial/ethnic disparities in transfer travel times were not observed, although 90th percentile driving times were highest for blacks.

CONCLUSION

Driving times do not pose a major geographic barrier to transfer of STEMI patients in Florida. A majority of STEMI patients could be transferred from STEMI referral hospitals to high-volume percutaneous coronary intervention centers within 30 minutes.

Prehospital evaluation and economic analysis of different coronary syndrome treatment strategies--PREDICT--rationale, development and implementation

BACKGROUND

A standard of prehospital care for patients presenting with ST-segment elevation myocardial infarction (STEMI) includes prehospital 12-lead and advance Emergency Department notification or prehospital bypass to percutaneous coronary intervention centres. Implementation of either care strategies is variable across communities and neither may exist in some communities. The main objective is to compare prehospital care strategies for time to treatment and survival outcomes as well as cost effectiveness.

METHODS/DESIGN

PREDICT is a multicentre, prospective population-based cohort study of all chest pain patients 18 years or older presenting within 30 mins to 6 hours of symptom onset and treated with nitroglycerin, transported by paramedics in a number of different urban and rural regions in Ontario. The primary objective of this study is to compare the proportion of study subjects who receive reperfusion within the target door-to-reperfusion times in subjects obtained after four prehospital strategies: 12-lead ECG and advance emergency department (ED) notification or 3-lead ECG monitoring and alert to dispatch prior to hospital arrival; either with or without the opportunity to bypass to a PCI centre.

DISCUSSION

We anticipate four challenges to successful study implementation and have developed strategies for each: 1) diversity in the interpretation of the ethical and privacy issues across 47 research ethics boards/committees covering 71 hospitals, 2) remote oversight of data guardian abstraction, 3) timeliness of implementation, and 4) potential interference in the study by concurrent technological advances. Research ethics approvals from academic centres were obtained initially and submitted to non academic centre applications. Data guardians were trained by a single investigator and data entry is informed by a detailed data dictionary including variable definitions and abstraction instructions and subjected to error and logic checks. Quality oversight provided by a single investigator. The window of the trial in each community has been confirmed with the base-hospital medical director to correspond to the planned technological advances of the system of care. We hope this comparative analysis across treatment strategies for clinical outcomes and cost will provide sufficient evidence to implement the superior strategy across all communities and improve outcomes for all STEMI patients.

Effect of time to electrocardiogram on time from electrocardiogram to fibrinolysis in acute myocardial infarction patients

OBJECTIVE

The American Heart Association (AHA) recommends a benchmark door-to-electrocardiogram (ECG) time of 10 minutes for acute myocardial infarction patients, but this is based on expert opinion (level of evidence C). We sought to establish an evidence-based benchmark door-to-ECG time.

METHODS

This retrospective cohort study used a population-based sample of patients who suffered an ST elevation myocardial infarction (STEMI) in Ontario between 1999 and 2001. Using cubic smoothing splines, we described (1) the relationship between door-to-ECG time and ECG-to-needle time and (2) the proportion of STEMI patients who met the benchmark door-to-needle time of 30 minutes based on their door-to-ECG time. We hypothesized nonlinear relationships and sought to identify an inflection point in the latter curve that would define the most efficient (benefit the greatest number of patients) door-to-ECG time.

RESULTS

In 2,961 STEMI patients, the median door-to-ECG and ECG-to-needle times were 8.0 and 27.0 minutes, respectively. There was a linear increase in ECG-to-needle time as the door-to-ECG time increased, up to approximately 30 minutes, after which the ECG-to-needle time remained constant at 53 minutes. The inflection point in the probability of achieving the benchmark door-to-needle time occurred at 4 minutes, after which it decreased linearly, with every minute of door-to-ECG time decreasing the average probability of achievement by 2.2%.

CONCLUSIONS

Hospitals that are not meeting benchmark reperfusion times may improve performance by decreasing door-to-ECG times, even if they are meeting the current AHA benchmark door-to-ECG time. The highest probability of meeting the reperfusion target time for fibrinolytic administration is associated with a door-to-ECG time of 4 minutes or less.

The influence of emergency medical services transport on Emergency Severity Index triage level for patients with abdominal pain

OBJECTIVES

The Emergency Severity Index (ESI) is a prospectively validated, five-level emergency department (ED) triage system designed to match triage acuity to both patient acuity and appropriate resource allocation. The study hypothesis was that, in practice, there exists an inappropriate bias toward triaging patients with abdominal pain to a higher ESI level based solely upon their mode of arrival to the ED.

METHODS

The authors performed a retrospective case-control study of patients presenting with abdominal pain. Patients were matched on sex, age (± 5 years), and date of arrival. Cases were those patients triaged to a Level 2, and controls were those triaged as Level 3. Conditional multiple variable logistic regression was used to evaluate the effect of the following variables on the odds of being triaged as Level 2: mode of arrival, systolic blood pressure (<90 mm Hg; normal, >140 mm Hg), heart rate, severe pain score (≥ 8 of 10), fever, race, history of cancer, and previous abdominal surgery. Age was also included in the regression modeling to confirm that matching was adequate. One-hundred cases and 100 controls were necessary to provide adequate sample size. A backward modeling technique was used, requiring a p < 0.05 for retention.

RESULTS

Of the 200 subjects, 52 arrived by emergency medical services (EMS) and 148 walked in. After matching for sex, age, and date of arrival, and after adjusting for heart rate, cancer diagnosis, and severe pain, the odds ratio (OR) for being triaged ESI Level 2 was 7.19 (95% confidence interval [CI] = 2.75 to 18.8, p < 0.0001) for EMS patients compared to walk-in patients. The admission rate for Level 2 patients was not different from that of Level 3 patients (49% vs. 35% of Level 3 patients, p = 0.06), but EMS patients were more likely to be admitted, regardless of ESI level assignment (65% vs. 34%, p < 0.001).

CONCLUSIONS

After adjusting for covariates, EMS patients with abdominal pain were more likely to be triaged to a higher acuity level. Triage level was not associated with admission, but patients arriving by EMS were more likely to be admitted. This may indicate that the effect of EMS arrival on triage level assignment is actually appropriate. Further research is necessary to validate whether mode of arrival should be incorporated in the initial ESI triage acuity assignment.

Investigation of disparities in geographic accessibility to emergency stroke and myocardial infarction care in East tennessee using geographic information systems and network analysis

PURPOSE

Stroke and myocardial infarction (MI) require timely geographic accessibility to emergency care. Historically, studies used straight line distances as measures of geographic accessibility. Recently, travel time has been recognized as a better indicator of accessibility because travel impedances can be considered. This study used finer grained transportation data and network analysis to investigate neighborhood disparities in travel time to emergency stroke and MI care.

METHODS

Travel times to stroke and cardiac centers were computed using network analysis, while considering distance, speed limit, road connectivity, and turn impedances. Neighborhoods within 30, 60, or 90 minutes travel were identified. Travel time by air ambulance was calculated and adjusted for flying speed and some delays.

RESULTS

Approximately 8% and 15% of the study population did not have timely geographic accessibility to emergency stroke and MI care, respectively. Populations with poor access were located in rural areas. The entire study population had timely access by air ambulance.

CONCLUSIONS

This study identified disparities in geographic accessibility to emergency stroke and MI care in East Tennessee. Use of air ambulance or telemedicine could play a vital role in addressing these disparities. This information is important for evidence-based health planning and resource allocation.

Delays in presentation with acute coronary syndrome in people with coronary artery disease in Australia and New Zealand

OBJECTIVES

To report time from the onset of symptoms to hospital presentation in Australian and New Zealand patients with subsequently confirmed acute coronary syndrome, and to identify factors associated with prehospital delay time in these patients.

METHODS

Patients with coronary artery disease enrolled in a randomized clinical trial testing an intervention to reduce delay in responding to acute coronary syndrome symptoms had been followed for 24 months. In cases of admission to the ED for possible acute coronary syndrome, medical records were reviewed to determine the diagnosis, prehospital delay time, mode of transport to the hospital and aspirin use before admission. Clinical and demographic data were taken from the trial database.

RESULTS

Patients (n= 140) had an average (SD) age of 67.3 (11.5) years; 36% were female. Two-thirds of patients went to hospital by ambulance and 89.3% had a final diagnosis of unstable angina. The median time from onset of symptoms to arrival at the ED was 2 h and 25 min (interquartile range 1:25-4:59); 12.1% arrived ≤ 1 h and 66% within 4 h. Multiple linear regression analysis showed that use of ambulance (Beta = 0.247, P= 0.012) and younger age (Beta = 0.198, P= 0.043) were independent predictors of shorter delay times.

CONCLUSION

The time from the onset of symptoms to hospital presentation was too long for maximal benefit from treatment in most patients. Further efforts are needed to reduce treatment-seeking delay in response to symptoms of acute coronary syndrome.

Comparison of impact of mortality risk on the survival benefit of primary percutaneous coronary intervention versus facilitated percutaneous coronary intervention

Available data suggest that thrombolytic therapy facilitated percutaneous coronary intervention (FPCI) is not beneficial, and recent analyses have shown a correlation between mortality risk and outcomes of patients with ST elevation myocardial infarctions treated with FPCI. The aim of this study was to analyze the impact of the mortality risk on the survival benefit of primary percutaneous coronary intervention (PPCI) compared to FPCI. A total of 13 trials enrolling 5,789 patients were pooled for analyses. PPCI survival benefit was calculated as the 30-day mortality after FPCI minus the 30-day mortality after PPCI, and the mortality rate of FPCI was interpreted as a proxy for mortality risk. A weighted metaregression was used to test the relation between mortality risk and explanatory variables. A fixed-effect linear regression analysis modeling the log odds ratio (PPCI/FPCI) as a linear function of the log odds of FPCI mortality was used to estimate the mortality risk that nullified the 30-day survival benefit of PPCI over FPCI. Across all studies, the absolute survival benefit ranged from -5.6 (favoring FPCI) to +7.2 (favoring PPCI). According to the slope of the regression line (-0.7, x-axis intercept -2.1) for the patients with baseline mortality risk > 4.2%, it is unlikely to obtain a survival benefit by FPCI compared to PPCI. In conclusion, the higher the mortality risk of patients with ST elevation myocardial infarctions, the higher the likelihood of a survival advantage of PPCI over FPCI.

Pain to hospital times after myocardial infarction in patients from Dalmatian mainland and islands, southern Croatia

AIM

To analyze pre-hospital delay in patients with myocardial infarction from mainland and islands of Split-Dalmatian County, southern Croatia.

METHODS

The study included all patients with myocardial infarction transported by ambulance to the University Hospital Split in 1999, 2003, and 2005. Pre-hospital delay was analyzed in the following intervals: pain-to-call, call-to-ambulance, ambulance-to-door, and door-to-coronary care unit interval. Patients were categorized according to the location from which they were transported: Split, mainland >15 km from Split, and islands.

RESULTS

There were 1314 patients (62.9% men) transported and hospitalized for myocardial infarction. Total pre-hospital delay (pain-to-hospital) was significantly reduced from 1999 to 2005 (5.2 hours vs 4.3 hours, P=0.011). Seventy-five patients (5.7%) were admitted to the coronary care unit within the recommended time-frame of less than 90 minutes, none of which was from the islands, while 248 patients (18.9%) were admitted more than 12 hours from the onset of pain.

CONCLUSION

Pre-hospital delay in patients with myocardial infarction in southern Croatia is still too long, especially in patients coming from outside of Split. Prognosis and survival of such patients may be improved by introducing changes to the health care system in remote areas, such as out-of-hospital thrombolysis, greater use of telemedicine, training of lay persons and paramedics in defibrillation, introduction of quality assessment mechanisms, and improved patient transport.

Is quality of cardiac hospital care a public or private good?

BACKGROUND

There are many studies examining the effects of financial pressure from different payment sources on hospital quality of care, but most have assumed that quality of care is a public good in that payment changes from one payer will affect all hospital patients rather than just those directly associated with the payer. Although quality of hospital care can be either a public or private good, few studies have tested which of these scenarios are more likely to hold.

OBJECTIVES

To examine whether the change in the magnitude of in-hospital mortality for Medicare and managed care patients is different based on financial pressure resulting from the Balanced Budget Act and growing managed care market penetration; and to examine what role hospital competition may play in affecting these changes.

DATA AND METHODS

The unit of analysis for the study was the hospital. Multiple data sources were used including the Agency for Healthcare Research and Quality State Inpatient Databases, American Hospital Association Annual Surveys, Area Resource File, and health maintenance organization data from InterStudy. A difference-in-difference-in-difference model was applied for a 2-period panel design.

RESULTS

In general, Balanced Budget Act financial pressure and managed care market share did not magnify the difference in in-hospital mortality rates between Medicare and managed care patients. The results suggest that quality of cardiac care in the hospital setting is more likely to be a public good; however, more investigation using other quality indicators and the role of hospital competition under different payment systems is recommended.

Improving use of prehospital 12-lead ECG for early identification and treatment of acute coronary syndrome and ST-elevation myocardial infarction

BACKGROUND

Performance of prehospital ECGs expedites identification of ST-elevation myocardial infarction and reduces door-to-balloon times for patients receiving reperfusion therapy. To fully realize this benefit, emergency medical service performance must be measured and used in feedback reporting and quality improvement.

METHODS AND RESULTS

This quasi-experimental design trial tested an approach to improving emergency medical service prehospital ECGs using feedback reporting and quality improvement interventions in 2 cities' emergency medical service agencies and receiving hospitals. All patients age > or =30 years, calling 9-1-1 with possible acute coronary syndrome, were included. In total, 6994 patients were included: 1589 patients in the baseline period without feedback and 5405 in the intervention period when there were feedback reports and quality improvement interventions. Mean age was 66+/-17 years, and women represented 51%. Feedback and quality improvement increased prehospital ECG performance for patients with acute coronary syndrome from 76% to 93% (P=<0.0001) and for patients with ST-elevation myocardial infarction from 77% to 99% (P=<0.0001). Aspirin administration increased from 75% to 82% (P=0.001), but the median total emergency medical service run time remained the same at 22 minutes. The proportion of patients with door-to-balloon times of < or =90 minutes increased from 27% to 67% (P=0.006).

CONCLUSIONS

Feedback reports and quality improvement improved prehospital ECG performance for patients with acute coronary syndrome and ST-elevation myocardial infarction and increased aspirin administration without prehospital transport delays. Improvements in door-to-balloon times were also seen.

Impact of 24-hr in-hospital interventional cardiology team on timeliness of reperfusion for ST-segment elevation myocardial infarction

OBJECTIVE

We studied the effect of 24 hr a day, 7 days a week interventional cardiology staff on door-to-balloon (D2B) time and mortality in patients undergoing primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Any delay in PPCI in acute STEMI is associated with higher mortality and, therefore, time to treatment should be as short as possible. Despite the use of several strategies, goal D2B time of <90 min remains elusive.

METHODS

The study examined 790 consecutive STEMI patients treated with PPCI as the reperfusion therapy of choice. Patients were grouped into a pre-24 x 7 and post-24 x 7 cohort to study the impact of the new protocol on D2B time and major adverse cardiovascular events (MACE) and mortality.

RESULTS

Median D2B time decreased from 99 min in the pre-24 x 7 group to 55 min in the post-24 x 7 group (P = 0.001) and was not influenced by time of day or day of week. Adjusted for patient and clinical characteristics, the pre-24 x 7 group had increased in-hospital cardiovascular mortality (odds ratio 1.94, 95% confidence interval 0.95-3.94; P = 0.048) and MACE (odds ratio 1.66, 95% confidence interval 1.10-2.49; P = 0.009) compared with the post-24 x 7 group. Prolonged D2B time was also associated with higher 1-year overall mortality in the pre-24 x 7 group compared with the post-24 x 7 group (12.8% vs. 8.1%; hazard ratio 1.17, 95% confidence interval 1.04-2.66; P = 0.044).

CONCLUSIONS

Round-the-clock, in-hospital interventional cardiology team consistently and significantly reduces D2B time, in-hospital cardiovascular mortality, MACE, and 1-year mortality in patients with STEMI.

Early identification and delay to treatment in myocardial infarction and stroke: differences and similarities

Background

The two major complications of atherosclerosis are acute myocardial infarction (AMI) and acute ischemic stroke. Both are life-threatening conditions characterised by the abrupt cessation of blood flow to respective organs, resulting in an infarction. Depending on the extent of the infarction, loss of organ function varies considerably.

In both conditions, it is possible to limit the extent of infarction with early intervention. In both conditions, minutes count.

This article aims to describe differences and similarities with regard to the way patients, bystanders and health care providers act in the acute phase of the two diseases with the emphasis on the pre-hospital phase.

Method

A literature search was performed on the PubMed, Embase (Ovid SP) and Cochrane Library databases.

Results

In both conditions, symptoms vary considerably. Patients appear to suspect AMI more frequently than stroke and, in the former, there is a gender gap (men suspect AMI more frequently than women).

With regard to detection of AMI and stroke at dispatch centre and in Emergency Medical Service (EMS) there is room for improvement in both conditions. The use of EMS appears to be higher in stroke but the overall delay to hospital admission is shorter in AMI. In both conditions, the fast track concept has been shown to influence the delay to treatment considerably.

In terms of diagnostic evaluation by the EMS, more supported instruments are available in AMI than in stroke. Knowledge of the importance of early treatment has been reported to influence delays in both AMI and stroke.

Conclusion

Both in AMI and stroke minutes count and therefore the fast track concept has been introduced. Time to treatment still appears to be longer in stroke than in AMI. In the future improvement in the early detection as well as further shortening to start of treatment will be in focus in both conditions. A collaboration between cardiologists and neurologists and also between pre-hospital and in-hospital care might be fruitful.

Comparative effectiveness of ST-segment-elevation myocardial infarction regionalization strategies

BACKGROUND

Primary percutaneous coronary intervention (PCI) is more effective on average than fibrinolytic therapy in the treatment of ST-segment-elevation myocardial infarction. Yet, most US hospitals are not equipped for PCI, and fibrinolytic therapy is still widely used. This study evaluated the comparative effectiveness of ST-segment-elevation myocardial infarction regionalization strategies to increase the use of PCI against standard emergency transport and care.

METHODS AND RESULTS

We estimated incremental treatment costs and quality-adjusted life expectancies of 2000 patients with ST-segment-elevation myocardial infarction who received PCI or fibrinolytic therapy in simulations of emergency care in a regional hospital system. To increase access to PCI across the system, we compared a base case strategy with 12 hospital-based strategies of building new PCI laboratories or extending the hours of existing laboratories and 1 emergency medical services-based strategy of transporting all patients with ST-segment-elevation myocardial infarction to existing PCI-capable hospitals. The base case resulted in 609 (95% CI, 569-647) patients getting PCI. Hospital-based strategies increased the number of patients receiving PCI, the costs of care, and quality-adjusted life years saved and were cost-effective under a variety of conditions. An emergency medical services-based strategy of transporting every patient to an existing PCI facility was less costly and more effective than all hospital expansion options.

CONCLUSION

Our results suggest that new construction and staffing of PCI laboratories may not be warranted if an emergency medical services strategy is both available and feasible.

The Strategic Reperfusion Early After Myocardial Infarction (STREAM) study

BACKGROUND

Primary percutaneous coronary intervention (PCI) has emerged as the preferred therapy for acute ST-elevation myocardial infarction (STEMI) provided it is performed in a timely fashion at an expert 24/7 facility. Fibrinolysis is a well-accepted alternative, especially in patients presenting early after symptom onset. The STREAM study will provide novel information on whether prompt fibrinolysis at first medical contact, followed by timely catheterization or rescue coronary intervention in STEMI patients presenting within 3 hours of symptom onset, represents an appropriate alternative strategy to primary PCI.

METHODS

Acute STEMI patients presenting early after symptom onset are eligible if PCI is not feasible within 60 minutes of first medical contact. This is an open-label, prospective, randomized, parallel, comparative, international multicenter trial. Patients are randomized to fibrinolysis combined with enoxaparin, clopidogrel, and aspirin, and cardiac catheterization within 6 to 24 hours or rescue coronary intervention if reperfusion fails within 90 minutes of fibrinolysis versus PCI performed according to local guidelines. Composite efficacy end points at 30 days include death, shock, heart failure, and reinfarction. Safety end points include ischemic stroke, intracranial hemorrhage, and major nonintracranial bleeding. Follow-up is extended to 1 year and includes all-cause mortality.

DISCUSSION

Continuing delays in achieving timely PCI remain a difficult issue. Many patients fail to achieve the desired reperfusion times of 90 to 120 minutes after first medical contact. The STREAM results will provide useful additional data on which to base informed therapeutic decisions.

Population density and racial differences in the performance of emergency medical services

This paper analyzes the existence and scope of possible racial differences/disparities in the provision of emergency medical services (EMS) response capability (time from dispatch to arrival at the scene and level of training of the responding team) using data on approximately 120,000 cardiac incidents in the state of Mississippi during 1995-2004. The conceptual framework and empirical analysis focus on the likely effects of population density on the efficient production of EMS as a local public good subject to congestion, and on the need to control adequately for population density to avoid bias in testing for racial differences. Models that control for aggregate population density at the county-level indicate "reverse" disparities: faster estimated response times for African-Americans than for whites. When a refined county-level measure of population density is used that incorporates differences in African-American and white population density by Census tract, the reverse disparity in response times disappears. There also is little or no evidence of race-related differences in the certification level of EMS responders. However, there is evidence that, controlling for response time, African-Americans on average were significantly more likely to be deceased than whites upon EMS arrival at the scene. The overall results are germane to the debate over the scope of conditioning variables that should be included when testing for racial disparities in health care.

Utilization of emergency medical services by patients with acute coronary syndromes in the Arab Gulf States

BACKGROUND

Emergency Medical Services (EMS) play a central role in caring for patients with acute coronary syndromes (ACS). To date, no data exist on utilization of EMS systems in the Arab Gulf States.

OBJECTIVE

To examine EMS use by patients with ACS in the Gulf Registry of Acute Coronary Events (Gulf RACE).

METHODS

Gulf RACE was a prospective, multinational study conducted in 2007 of all patients hospitalized with ACS in 65 centers in six Arab countries. Data were analyzed based on mode of presentation (EMS vs. other).

RESULTS

Of 7859 patients hospitalized with ACS through the emergency department (ED), only 1336 (17%) used EMS, with wide variation among countries (2% in Yemen to 37% in Oman). Younger age (odds ratio [OR] 1.09; 95% confidence interval [CI] 1.03-1.15 per 10-year decrement), presence of chest pain (OR 1.73; 95% CI 1.48-2.03), prior myocardial infarction (OR 1.58; 95% CI 1.34-1.86), prior percutaneous coronary intervention (OR 1.27; 95% CI 1.02-1.59), family history of premature coronary disease (OR 1.25; 95% CI 1.09-1.51), and current smoking (OR 1.30; 95% CI 1.13-1.50) were independently associated with not utilizing EMS. Patients with ST-segment elevation myocardial infarction/left bundle branch block myocardial infarction who were transported by EMS were significantly less likely to exhibit major delay in presentation, and were significantly more likely to receive favorable processes of care, including shorter door-to-electrocardiogram time, more frequent coronary reperfusion therapy, and thrombolytic therapy within 30 min of arrival at the ED.

CONCLUSION

Despite current recommendations, fewer than 1 in 5 patients with ACS use EMS in the Arab Gulf States, highlighting a significant opportunity for improvement. Factors causing this underutilization deserve further investigation.

Utilisation of emergency medical service among Singapore patients presenting with ST-segment elevation myocardial infarction: prevalence and impact on ischaemic time

BACKGROUND

Previous studies in Western countries found that the emergency medical service (EMS) was under-used in patients with myocardial infarction.

AIM

We sought to determine the prevalence of immediate EMS utilisation among Singapore patients presenting with ST-segment elevation myocardial infarction (STEMI), and correlated the use of the EMS with the symptom-to-balloon and door-to-balloon times.

METHODS

We studied 252 patients admitted with STEMI to our institution from August 2008 to September 2009. Information regarding demographic characteristics, whether EMS was used, reperfusion procedural details and mortality rates were collected prospectively.

RESULTS

Among the recruited patients, 89 (35.3%) used the EMS (EMS group) and 163 (64.7%) did not use the EMS (non-EMS group). In the latter group, 98 (60.1%) arrived at our institution through their own transport, 56 (34.4%) first consulted general practitioners, and 9 (5.5%) initially consulted another hospital without acute medical services. Among the 245 (out of 252, 97.2%) patients who received percutaneous coronary intervention (PCI), the EMS group was more likely to undergo primary PCI (P= 0.003) while the non-EMS group was more likely to undergo non-urgent PCI (P= 0.002). In patients who underwent primary PCI, the EMS group had a shorter symptom-to-balloon time (average difference 81.6 min, P= 0.002). The door-to-balloon time was similar for both groups.

CONCLUSION

Despite the availability of a centralised EMS, 64.7% of patients with STEMI did not contact EMS at presentation. These patients were less likely to receive primary PCI and had a significantly longer symptom-to-balloon time.

Prehospital delay and its impact on time to treatment in ST-elevation myocardial infarction

PURPOSES

We performed this study to assess the impact of pre-hospital time on the patient's outcome.

PROCEDURES

Starting from the symptoms onset, "total time to treatment" was divided into less than or equal to 120 minutes and more than 120 minutes ("pre-hospital time" of ≤ or > 30 minutes respectively). Adverse patient's outcomes were compared in the two subgroups.

FINDINGS

Our patients had a mean age of 63 (±13) years. On-scene time (17.8 ± 9.4 minutes), was the biggest fraction of "pre-hospital time". Comparing the groups with "Total time to treatment" of >120 minutes vs. ±120 minutes ("pre-hospital time" of >30 vs. ≤30 minutes), mortalities were 4 vs. 0 and transfers to a tertiary care facility were 3 vs.1.

CONCLUSIONS

Most of the pre-hospital time in STEMI was spent on the scene and we suggest "total time to treatment" as a core measure instead of "door to balloon time".

Frequency of non-ST-segment elevation injury patterns on prehospital electrocardiograms

INTRODUCTION

Prehospital electrocardiograms (ECGs) have been recommended to facilitate early diagnosis of ST-segment elevation myocardial infarction (STEMI). However, prehospital ECGs can also be used to triage patients with non-ST-segment elevation acute coronary syndromes, who comprise a majority of patients with ischemic events presenting by ambulance to overcrowded emergency departments.

OBJECTIVE

We assessed the frequency of non-ST-segment elevation injury patterns on prehospital ECGs in patients with a chief complaint of chest pain evaluated by the emergency medical services (EMS) system.

METHODS

We analyzed prehospital ECGs of patients with the chief complaint of chest pain during a nine-month period. The ECGs were divided into three categories: injury pattern; no injury pattern; and technically uninterpretable. Injury pattern criteria were as follows: 1) regional ST depression >or=1.0 mm; 2) regional T-wave inversion (TWI) >or=3 mm; 3) left bundle branch block (LBBB); and 4) regional ST-segment elevation >or=1.0 mm. Descriptive statistics with 95% confidence intervals (CIs) are presented.

RESULTS

Prehospital ECGs were obtained for 322 of 340 chest pain patients: 72% were men; the average age was 60 years (range 18-96 years). Seventy-seven ECGs (24%, 95% CI 19.3-28.9%) met the criteria for injury pattern, 230 (71%) did not show injury, and 15 (5%) were uninterpretable. Of the 77 ECGs that exhibited an injury pattern, 39 (51%) showed ST depression, seven (9%) TWI, seven (9%) LBBB, and 24 (31%) ST-segment elevation. Thus, non-ST-segment elevation injury patterns (ST depression/TWI/LBBB) accounted for 53 (17%, 95% CI 12.6-20.9) of the total 322 prehospital ECGs.

CONCLUSION

Our findings demonstrate a relatively high frequency (17%) of non-ST-segment elevation injury patterns on prehospital ECGs of patients who summon EMS because of chest pain. These results suggest the potential of prehospital ECGs to facilitate early triage in these high-risk chest pain patients who present to overcrowded emergency departments.

Inappropriate dispatcher decision for emergency medical service users with acute myocardial infarction

OBJECTIVES

Current guidelines recommend utilization of prehospital emergency medical services (EMSs) by patients with ST-elevation myocardial infarction (STEMI). The aims of this study were to estimate the percentage of inappropriate initial dispatcher decisions and determine their impact on delays in reperfusion therapy for EMS users with STEMI.

METHODS

As part of a prospective regional registry of patients with STEMI, we analyzed the original data for 245 patients who called a university hospital-affiliated EMS call center in France. The primary study outcome was time to reperfusion therapy calculated from the documented date and time of the first patient call.

RESULTS

The initial EMS dispatcher's decision was appropriate (ie, dispatching a mobile intensive care unit staffed by an emergency or critical care physician) for 171 (70%) patients and inappropriate for 74 (30%) patients. Inappropriate decisions included referring the patient to a family physician (n = 59), providing medical advice (n = 9), and dispatching an ambulance (n = 6). Inappropriate initial decisions resulted in increased median time to reperfusion for 140 patients receiving fibrinolysis (95 vs 53 minutes; P < .001) and 91 patients undergoing primary percutaneous coronary intervention (170 vs 107 minutes; P < .001). In-hospital mortality was not different between the 2 study groups (6.8% vs 9.9%; P = .42).

CONCLUSION

The initial dispatcher's decision is inappropriate for 30% of EMS users with STEMI and results in substantial delays in time to reperfusion therapy. Accuracy of telephone triage should be improved for patients who activate EMSs in response to symptoms suggestive of acute coronary syndrome.

Trends in acute myocardial infarction incidence and mortality over 30 years in Japan: report from the MIYAGI-AMI Registry Study

BACKGROUND

Worldwide, the rate of aging is highest in Japan, especially the female population. To explore the trends for acute myocardial infarction (AMI) in Japan, the MIYAGI-AMI Registry Study has been conducted for 30 years since 1979, whereby all AMI patients in the Miyagi prefecture are prospectively registered.

METHODS AND RESULTS

In 1979-2008, 22,551 AMI patients (male/female 16,238/6,313) were registered from 43 hospitals. The age-adjusted incidence of AMI (/100,000persons/year) increased from 7.4 in 1979 to 27.0 in 2008 (P<0.001). Although control of coronary risk factors remained insufficient, the rates of ambulance use and primary percutaneous coronary intervention (PCI) have increased, and the overall in-hospital mortality (age-adjusted) has decreased from 20.0% in 1979 to 7.8% in 2008 (P<0.0001). However, the in-hospital mortality remains relatively higher in female than in male patients (12.2% vs 6.3% in 2008). Female patients were characterized by higher age and lower PCI rate.

CONCLUSIONS

The MIYAGI-AMI Registry Study demonstrates the steady trend of an increasing incidence, but decreasing mortality, for AMI in Japan over the past 30 years, although the female population still remains at higher risk for in-hospital death, despite improvements in the use of ambulances and primary PCI. (Circ J 2010; 74: 93 - 100).

Mode of arrival does not predict myocardial infarction in patients who present to the ED with chest pain

Aims

This study aims to determine if patients who arrive by ambulance with a chief complaint of chest pain have a higher risk of myocardial infarction (MI) than those who arrive via alternate transportation.

Methods

All patients ages 18–99 who presented to an urban academic ED between January 2006 and July 2006 with a chief complaint that included “chest pain” were eligible for retrospective analysis. Patients who were transferred or who left without being seen or against medical advice were excluded. Myocardial infarction was defined as patients who were admitted and who had elevated troponin I or went urgently to catheterization laboratory and had >90% occlusion of a vessel, with a final clinical impression of MI.

Results

There were 690 visits for chest pain during the study period, representing 4% of total ED census. A total of 39 visits met exclusion criteria, and 37 patients had 52 repeat visits, leaving 599 unique patients included for analysis. Mean age was 48.8 ± 1.4 years (SD 17.7), 44.6% were female, and 35 patients (5.8%) were diagnosed with MI. In all, 157 patients (26.2%) arrived via EMS. Patients who arrived by ambulance did not have a significant difference in rate of MI when compared with alternate transportation [7.0% vs. 5.4%, OR (95% CI) = 1.3 (0.6–2.7), p = 0.469]. Only 31.4% (11/35) of patients who ultimately were diagnosed with MI arrived by ambulance.

Conclusion

We were unable to show a significant difference in rate of MI between patients who arrived via ambulance or private transportation. Equal consideration and urgency should be given to both types of patients when they arrive at the ED.

A randomized clinical trial to reduce patient prehospital delay to treatment in acute coronary syndrome

BACKGROUND

Delay from onset of acute coronary syndrome (ACS) symptoms to hospital admission continues to be prolonged. To date, community education campaigns on the topic have had disappointing results. Therefore, we conducted a clinical randomized trial to test whether an intervention tailored specifically for patients with ACS and delivered one-on-one would reduce prehospital delay time.

METHODS AND RESULTS

Participants (n=3522) with documented coronary heart disease were randomized to experimental (n=1777) or control (n=1745) groups. Experimental patients received education and counseling about ACS symptoms and actions required. Patients had a mean age of 67+/-11 years, and 68% were male. Over the 2 years of follow-up, 565 patients (16.0%) were admitted to an emergency department with ACS symptoms a total of 842 times. Neither median prehospital delay time (experimental, 2.20 versus control, 2.25 hours) nor emergency medical system use (experimental, 63.6% versus control, 66.9%) was different between groups, although experimental patients were more likely than control to call the emergency medical system if the symptoms occurred within the first 6 months following the intervention (P=0.036). Experimental patients were significantly more likely to take aspirin after symptom onset than control patients (experimental, 22.3% versus control, 10.1%, P=0.02). The intervention did not result in an increase in emergency department use (experimental, 14.6% versus control, 17.5%).

CONCLUSIONS

The education and counseling intervention did not lead to reduced prehospital delay or increased ambulance use. Reducing the time from onset of ACS symptoms to arrival at the hospital continues to be a significant public health challenge.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov. Identifier NCT00734760.

Influence of Ambulance Arrival on Emergency Department Time to Be Seen

OBJECTIVES

For a limited number of presenting complaints, arrival by ambulance has been shown in some emergency departments to decrease time to be seen by a physician. We sought to determine if this time advantage could be demonstrated as a national trend over a variety of presenting complaints.

METHODS

A secondary analysis was performed on the National Hospital Ambulatory Medical Care Survey, a national probability sample of emergency department visits. To compare waiting times between patients arriving by ambulance and those arriving by walk-in, a survival analysis was performed using univariate and multivariate Cox proportional hazards models. Primary variables of interest were mode of arrival, waiting time to see physician, and immediacy to be seen (triage category). The weighted values were utilized to produce national estimates. Patients who left without being seen were treated as right censored data.

RESULTS

A total of 61,130 records, weighted to represent 268.3 million emergency department visits from 1997 to 2000, were included in the analysis. Patients arrived by ambulance in 14.4% of these cases. Median wait time for patients arriving by ambulance was 14.1 minutes (95% confidence interval [CI], 4.3 to 34.2) as compared with 26.0 minutes (95% CI, 11.5 to 55.1) for patients who arrived by walk-in. In the multivariate analysis, arrival by ambulance offered a 25.0% (95% CI, 19.0% to 31.6%) time advantage over walk-in and a 40.8% (95% CI, 23.5% to 58.7%) time advantage over arrival by public service.

CONCLUSIONS

Arrival by ambulance offered a time to be seen advantage for a broad range of presenting complaints in the National Hospital Ambulatory Medical Care Survey across all triage categories.

Path Analysis Modeling Indicates Free Transport Increases Ambulance Use for Minor Indications

INTRODUCTION

Clinically unnecessary ambulance transport is increasing, diverting limited resources from patients needing ambulance transport. It was anecdotally observed that inappropriate ambulance use increased after abolition of a direct patient cost for ambulance transport.

HYPOTHESIS

In July 2003, direct patient fees were abolished in favor of a universally applied ambulance levy, potentially leading to increased ambulance use by patients with low illness acuity and admission rates.

METHODS

The influence of age, illness acuity, and need for admission on ambulance use was assessed for 55,397 emergency department attendances in 2002 and 2004. Ambulance users were compared with nonusers in both years and attendances for 2002 compared with 2004 using chi-square test for two groups. Logistic regression provided a multivariate model leading to ambulance use. Path analysis modeling to assess interrelationships between factors associated with ambulance use was developed.

RESULTS

Ambulance users in both years were older, had more acute illness, and had greater need for admission compared with nonusers. The odds ratio (OR) of arrival by ambulance in 2004 compared with 2002 was 1.14 (95% confidence interval, [CI], 1.12 to 1.17). In 2002, ambulance users were older (OR, 1.42; 95% CI, 1.40 to 1.43), were more likely to need admission (OR, 2.28; 95% CI, 2.16 to 2.4) and had higher illness acuity (OR, 2.02; 95% CI, 1.94 to 2.09). There was a negative correlation between 2004 and illness acuity.

CONCLUSIONS

Ambulance use increased in 2004 after patient transport fees were abolished. Increased use was associated with decreased age, clinical acuity, and admission need. Abolishing direct patient cost stimulates ambulance use, potentially including inappropriate transport. Path analysis to assess the effect of changed funding on ambulance use could be used to the influence of other locally relevant factors contributing to ambulance use.

Use of emergency medical services in patients with acute myocardial infarction in China

BACKGROUND

Although guidelines strongly recommend use of the Emergency Medical Systems (EMS) by patients with acute myocardial infarction (AMI), it remains underutilized in western countries. Information about its current use in China is unclear. The objective of this study was to examine the use of the EMS by patients with AMI in China, and investigate factors affecting its use.

METHODS

A prospective survey study, which included 803 patients with AMI who were admitted to 21 hospitals in China between November 1, 2005 and December 31, 2006.

RESULTS

Only 39.5% of patients called up the EMS at the onset of symptoms (EMS group, n=317), whereas the rest presented to the hospital by some other means (self-transport group, n=486, 60.5%). Predictors of EMS users were older age, symptom onset at evening, unbearable symptoms, having received training and acquired knowledge on heart attack, as well as having a higher income and medical history of heart failure or stroke. Prehospital delay (median 110 min vs. 143 min, p<0.001), door to needle time (median 85 min vs. 93 min, p<0.005) and door-to-balloon time (median 118 min vs. 160 min, p<0.001) were significantly shorter in the EMS group. The early reperfusion rate was also significantly higher in the EMS group (84.8% vs. 78.2%, p=0.019), mainly because of a greater incidence of primary percutaneous coronary intervention (68.1% vs. 61.7%, p=0.046).

CONCLUSIONS

The emergency medical services are underutilized by patients with AMI in China. Use of the EMS may be advantageous in view of greater administration of reperfusion therapy. New public health strategies should be developed to facilitate greater use of the EMS for AMI.

An emergency physician activated protocol, 'Code STEMI' reduces door-to-balloon time and length of stay of patients presenting with ST-segment elevation myocardial infarction

INTRODUCTION

National consensus guidelines recommend that ST-segment elevation myocardial infarction (STEMI) patients achieve a door-to-balloon time of < 90 min. We sought to determine if emergency physician initiated simultaneous activation of the cardiac catheterisation laboratory team and the on-call interventional cardiologist has any impact on reducing door-to-balloon-times at our hospital.

METHODS

A total of 72 consecutive STEMI patients were evaluated from January 2007 to December 2007. The emergency physician activated Code STEMI required concurrent activation of cardiac catheterisation personnel and the on-call interventional cardiologist by the emergency physician. These patients were compared with our staff cardiologist activated primary angioplasty protocol from January 2006 to December 2006 for 51 consecutive STEMI patients. The primary outcome was to measure median door-to-balloon time between both groups. Secondary end-points included the individual components of door-to-balloon times (i.e. door-to-ECG time), peak troponin-I level within 24 h, length of stay and all-cause in-hospital mortality.

RESULTS

Median door-to-balloon time decreased overall (112 vs. 74 min, p < 0.001). Of the three components of door-to-balloon time analysed, the ECG to cardiac catheterization laboratory time exhibited the largest area of improvement with 16 min absolute reduction in median door-to-balloon time. Median peak troponin levels (50 vs. 25 ng/ml, p < 0.001), and hospital length of stay (4 vs. 3 days, p < 0.01) decreased. We did not see any statistically significant difference in all-cause in-hospital mortality (p = 0.6).

CONCLUSIONS

Emergency physician activation of the Code STEMI significantly reduces door-to-balloon time to within national standards of care, and length of stay in STEMI patients.

Emergency department triage of acute myocardial infarction patients and the effect on outcomes

STUDY OBJECTIVE

More than half of all acute myocardial infarction patients still do not meet benchmark reperfusion times, and the triage assessment that all patients receive when they arrive at an emergency department (ED) is a hospital-level process that has not been studied as a potential contributor to delays. Our objective was to examine the triage of acute myocardial infarction patients (ST-elevation and non-ST elevation myocardial infarction) and determine whether it is associated with subsequent delays in acute myocardial infarction processes of care.

METHODS

We conducted a retrospective cohort analysis of a population-based cohort of acute myocardial infarction patients admitted to 102 acute care hospitals in Ontario, Canada, from July 2000 to March 2001. Main outcome measures were the rate of low-acuity triage (defined as a Canadian Triage and Acuity Scale score of III, IV, or V) among acute myocardial infarction patients and its association with delays in time from ED arrival to initial ECG (door-to-ECG time) and to administration of fibrinolysis (door-to-needle time).

RESULTS

Among 3,088 acute myocardial infarction patients, the rate of low acuity triage was 50.3%. Median door-to-ECG and door-to-needle time was 12.0 and 40.0 minutes, respectively. In adjusted quantile regression analyses, low-acuity triage was independently associated with a 4.4-minute delay in median door-to-ECG time and a 15.1-minute delay in median door-to-needle time. The adjusted odds of achieving benchmark door-to-ECG and door-to-needle times were 0.54 (95% confidence interval 0.46 to 0.65) and 0.44 (95% confidence interval 0.30 to 0.65), respectively, for acute myocardial infarction patients assigned a low-acuity ED triage score.

CONCLUSION

Half of acute myocardial infarction patients were given a low acuity triage score when they presented to an ED in Ontario, which was independently associated with substantial delays in ECG acquisition and to reperfusion therapy. The quality of ED triage may be an important factor limiting performance on key measures of quality of acute myocardial infarction care.

Elapsed time in emergency medical services for patients with cardiac complaints: are some patients at greater risk for delay?

BACKGROUND

In patients with a major cardiac event, the first priority is to minimize time to treatment. For many patients, first contact with the health system is through emergency medical services (EMS). We set out to identify patient-level and neighborhood-level factors that were associated with elapsed time in EMS.

METHODS AND RESULTS

A retrospective cohort study was conducted in 10 municipalities in Dallas County, Tex, from January 1 through December 31, 2004. The data set included 5887 patients with suspected cardiac-related symptoms. The region was served by 29 hospitals and 98 EMS depots. Multivariate models included measures of distance traveled, time of day, day of week, and patient and neighborhood characteristics. The main outcomes were elapsed time in EMS (continuous; in minutes) and delay in EMS (dichotomous; >15 minutes beyond median elapsed time). We found positive associations between patient characteristics and both average elapsed time and delay in EMS care. Variation in average elapsed time was not large enough to be clinically meaningful. However, approximately 11% (n=647) of patients were delayed >or=15 minutes. Women were more likely to be delayed (adjusted odds ratio, 1.52; 95% confidence interval, 1.32 to 1.74), and this association did not change after adjusting for other characteristics, including neighborhood socioeconomic composition.

CONCLUSIONS

Compared with otherwise similar men, women have 50% greater odds of being delayed in the EMS setting. The determinants of delay should be a special focus of EMS studies in which time to treatment is a priority.

Trends in reperfusion strategies, door-to-needle and door-to-balloon times, and in-hospital mortality among patients with ST-segment elevation myocardial infarction enrolled in the National Registry of Myocardial Infarction from 1990 to 2006

BACKGROUND

Among patients with ST-segment elevation myocardial infarction (STEMI), rapid reperfusion is associated with improved mortality. As such, door-to-needle (D2N) and door-to-balloon (D2B) times have become metrics of quality of care and targets for intense quality improvement.

METHODS

The National Registry of Myocardial Infarction (NRMI) collected data regarding reperfusion therapy, its timing and in-hospital mortality among STEMI patients from 1990 through 2006.

RESULTS

Since 1990, NRMI has enrolled 1,374,232 STEMI patients at 2,157 hospitals. Among those, 774,279 (56.3%) were eligible for reperfusion upon arrival. The proportion receiving fibrinolytic therapy fell from 52.5% in 1990 to 27.6% in 2006 (P < .001), while the proportion undergoing primary percutaneous coronary intervention (pPCI) increased from 2.6% to 43.2%. Among reperfusion-eligible patients who received fibrinolytic therapy, there was a nearly linear decline in median D2N time from 59 minutes in 1990 to 29 minutes in 2006 (P < .001 for trend) as well as a decrease in mortality from 7.0% in 1994 to 6.0% in 2006 (P < .001). Among those undergoing pPCI, D2B time among nontransfer patients declined linearly from 111 minutes in 1994 to 79 minutes in 2006 (P < .001) with a decline in mortality from 8.6% to 3.1% (P < .001). The relative improvement in mortality attributable to improvements in D2N time was 16.3% and to D2B time was 7.5%.

CONCLUSIONS

Since 1990, there has been a progressive decline in D2N and D2B time among reperfusion-eligible STEMI patients. These improvements have contributed, at least in part, to a progressive decline in mortality.