Once and a while we do help....

[Ace844]

(Acad Emerg Med Volume 13 @ Number 1 84-89, published online before print December 19, 2005, doi: 10.1197/j.aem.2005.07.042 © 2006 Society for Academic Emergency Medicine, Prehospital 12-lead Electrocardiography Impact on Acute Myocardial Infarction Treatment Times and Mortality: A Systematic Review

Laurie J. Morrison, MD, FRCPC, MSc, Steven Brooks, MD, Bruce Sawadsky, MD, CCFP-EM, Andrew McDonald, MD, FRCPC, MHSc and P. Richard Verbeek, MD, FRCPC

From the Department of Emergency Services, Sunnybrook and Women's College Health Sciences Center, (LJM, BS, AM, PRV), Toronto, Canada; Division of Emergency Medicine, Department of Medicine (LJM, AM, PRV), and Division of Emergency Medicine, Department of Family and Community Medicine (BS), University of Toronto, Toronto, Canada; Faculty of Health Sciences, School of Medicine, Queen's University (SB), Kingston, Canada; and Division of Emergency Medicine, Department of Surgery, University of British Columbia (SB), Vancouver, Canada; Ontario Air Ambulance Base Hospital Program (BS), Toronto, Canada. Address for correspondence and reprints: Laurie J. Morrison, MD, FRCPC, MSc, Prehospital and Transport Medicine Research Program, Sunnybrook and Women's College Health Sciences Center, Suite B1 03, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada. Fax: 416-480-5558; e-mail: laurie.morrison@sw.ca)

Objectives: Prehospital 12-lead electrocardiogram (PHECG) interpretation and advance emergency department (ED) notification may improve time-to-treatment intervals for a variety of treatment strategies to improve outcome in acute myocardial infarction. Despite consensus guidelines recommending this intervention, few emergency medical services (EMS) employ this. The authors systematically reviewed the literature to report whether mortality or treatment time intervals improved when compared with standard care.

Methods: The authors used the Cochrane strategy to search MEDLINE, EMBASE, Current Contents, Dissertation Abstracts, Cochrane Library, and Index of Scientific and Technical Proceedings. Bibliographies and grant-agency Websites were reviewed, and primary investigators and industry were contacted for published and unpublished studies. Inclusion criteria included PHECG and advance ED notification versus standard EMS care; controlled trials; English only; and evaluation of treatment time intervals, all-cause mortality, or both. Study selection was hierarchical, blinded, and independent. Agreement at each level of review was evaluated by using a kappa statistic. Study quality was measured with a validated scale and was interpreted by two independent reviewers.

Results: A total of 1,283 citations were identified, and five studies met the inclusion criteria. The weighted kappa for selection was 0.61 (standard error [sE], 0.045) for titles, 0.63 (SE, 0.051) for abstracts, and 0.79 (SE, 0.146) for full articles. Mean study quality measures by two independent reviewers were 6.0/15 and 5.5/15 (correlation coefficient, 0.85; p = 0.06). PHECG and advance ED notification increased the weighted mean on-scene time by 1.2 minutes (95% confidence interval [95% CI] = –0.84 to 3.2). The weighted mean door-to-needle interval was shortened by 36.1 minutes (95% CI = 9.3 to 63.0: range of means, 22–48 minutes vs. 50–97 minutes). One study reported all-cause mortality, with a statistically nonsignificant reduction from 15.6% to 8.4%.

Conclusions: For patients with AMI, the literature would suggest that PHECG and advanced ED notification reduces in hospital time to fibrinolysis. One controlled trial found no difference in mortality with this out-of-hospital intervention.

Or do we..seeing as this was a retrospective review...wat do you think..?

out here,

ACE844

[AZCEP]

It all depends on the receiving facility's ability to believe what the prehospital folks are telling them. Then of course, they have to relay the information to the cath lab in a way that information isn't lost.

[Ace844]

(American Heart Journal

Volume 152 @ Issue 1 , July 2006, Pages 11-18

doi:10.1016/j.ahj.2005.11.007

Copyright © 2006 Mosby, Inc. All rights reserved.

Curriculum in Cardiology

The 12-lead electrocardiogram as a predictive tool of mortality after acute myocardial infarction: Current status in an era of revascularization and reperfusion

Mircea Petrina MDa, b, , , Shaun G. Goodman MD, MScc, d, e, and Kim A. Eagle MD, FACCa,

aUniversity of Michigan Medical Center, Ann Arbor, MI

bUniversity of Illinois at Chicago Michael Reese Hospital Program, Chicago, IL

cUniversity of Toronto, Toronto, Ontario, Canada

dCanadian Heart Research Centre, Toronto, Ontario, Canada

eSt Michael's Hospital, Toronto, Ontario, Canada

Received 5 April 2005; accepted 11 November 2005. Available online 13 July 2006.)

Many recently published studies established the admission electrocardiogram as an excellent source of prognostic information in patients presenting with acute myocardial infarction. Using our search criteria, we identified a large number of articles but selected only the most relevant in each category. The best predictors of increased short-term mortality are ventricular tachycardia (odds ratio [OR] 6.1, 95% CI 4.6-8.3), ST-segment deviations (OR 5.1, 95% CI 4.6-8.3), high-degree atrioventricular block (OR 5.1, 95% CI 2.1-11.9), and long QRS duration (OR 4.2, 95% CI 1.8-10.4). For increased long-term mortality, the best predictors were ST-segment depression (OR 5.7, 95% CI 2.8-11.6), ST-segment elevation (OR 3.3, 95% CI 2.1-5.1), and left bundle-branch block (OR 2.8, 95% CI 1.8-4.3). In addition, our review discusses electrocardiographic markers of poor outcome that were not independent risk factors on multivariate analysis, conflicting findings, and knowledge gaps that can help plan future research efforts.

There are multiple studies assessing the predictive power of different electrocardiographic (ECG) parameters in patients presenting with suspected acute myocardial infarction (AMI). The most commonly reported abnormalities are conduction blocks and ST-segment changes. To our knowledge, there are no review articles or meta-analyses published recently on the subject and only a few original studies performed multivariate analysis to assess the potential prognostic value of multiple ECG parameters simultaneously. This review identifies, critically appraises, and summarizes the best available evidence correlating both traditional and more recently studied ECG predictors of mortality after AMI.

Methods

A MEDLINE search performed with the search terms AMI, mortality, and ECG identified 424 articles. The following inclusion criteria were then applied: admission for AMI, at least 500 patients per study, and modern revascularization era (ie, 1990 to present), resulting in 103 selected articles. When similar studies were found on the same ECG parameter and follow-up length pair, the studies presenting general inclusion criteria and the most robust statistical methods were included in the final revision. The level of statistical significance (P value) for study reports to be considered in our review was .05.

The reviewed articles were sorted based on the ECG phase of interest in the normal sequence from cardiac depolarization to repolarization and by the duration of patient follow-up, with short term defined as <6 months and longer term defined as ≥6 months. Whenever available, for each ECG variable included, the estimated prevalence, the impact, and the independence after multivariate analysis were reported.

Results

Normal presentation ECG

Welch et al1 reported in a study of 391 208 patients diagnosed with AMI that normal (odds ratio [OR] 0.59, 95% CI 0.56-0.63) or nonspecific ECG (OR 0.70, 95% CI 0.68-0.72) conferred lower inhospital mortality risk compared with diagnostic ECG defined as ST-segment elevation (STE) or ST-segment depression (STD) or new left bundle-branch block (LBBB). Patients discharged with missed diagnosis, however, had a high mortality rate (10.5%).

Normal or nonspecific admission ECG in the setting of AMI is thus protective for short-term mortality, and long-term mortality studies were not identified.

Heart rate

In a study by Granger et al2 on 11 389 patients enrolled with acute coronary syndrome (ACS) in the GRACE registry, an increased heart rate (HR) was an independent risk factor for higher inhospital mortality (OR 1.2, 95% CI 1.15-1.24). In 2 GUSTO-I substudies of 34 166 patients with St-segment elevation acute myocardial infarction (STEMI, the median HR in patients who died within 30 days was 80 beat/min (vs overall median 74 beat/min)3 and tachycardia (84 vs 60 beat/min)4 was reported as an independent predictor of 30-day mortality (OR 1.49, 95% CI 1.41-1.59). The authors3 also described increased 30-day mortality in patients with bradycardia (OR not reported).

In a study on 1807 patients with AMI, Hjalmarson et al5 also reported that a higher admission HR predicted a higher inhospital and 1-year mortality. The total mortality (day 2 to 1 year) was reported to increase with increased HR from 15% (for an admission HR 50-60 beat/min) to 41% (HR >90 beat/min) and 48% (HR ≥110 beat/min). In another study from GRACE by Eagle et al6, 15 007 patients with ACS had higher 6-month mortality with progressive increases in baseline HR; thus, an average increase of 30 beat/min was an independent risk factor for increased mortality (OR 1.3, 95% CI 1.16-1.43).

The mortality reported by Hjalmarson et al5 was higher than in the GRACE registry, possibly because of secular trends and different inclusion criteria (only patients with AMI were studied in the former, all ACS in the latter). All studies thus demonstrate a U-shape relation between HR and mortality, both bradycardia and tachycardia being independent predictors of mortality.

Atrial fibrillation

Newly diagnosed atrial fibrillation (AF) was found to be an independent predictor of inhospital adverse events in a study by Sakata et al7 and in the GRACE registry by Mehta et al8 (OR 1.65, 95% CI 1.3–2.1). The GUSTO-I trial9 of 40 890 patients with AMI reported that AF developed after admission was an independent predictor for 30-day mortality (OR 1.4, 95% CI 1.3-1.5) in contrast to baseline AF, which was not (OR 1.1, 95% CI 0.88-1.30).

Behar et al10 found an incidence of 9.9% of paroxysmal AF among 5803 study patients, and it was a significant independent predictor for 1- and 5-year mortality (relative risk [RR] 1.28, 95% CI 1.12-1.46). Sakata et al7 reported both early- and late-onset AF (first or after 24 hours) as independent predictors of 8-year mortality (OR not available).

In conclusion, new-onset AF in the setting of AMI is a strong predictor of poor long- and short-term outcome.

Sustained monomorphic ventricular tachycardia

Mont et al11 reported that sustained monomorphic ventricular tachycardia (SMVT) occurred in 1.9% of 1120 patients in the early phase of AMI (first 48 hours) and predicted an increased inhospital mortality (43% vs 11% without SMVT) even after multivariate adjustment (OR 5.0, 95% CI 1.63-15.3). An analysis of 16 189 patients with AMI from GISSI-3 registry12 assessed the incidence and short-term prognosis of SMVT with later onset (patients surviving the first 48 hours after AMI). The incidence of late-onset SMVT was 1% and predicted higher 6-week mortality (35% vs 5% without SMVT), even after adjustments using a proportional hazards regression model (hazard ratio 6.13, 95% CI 4.56-8.25).

A very large ischemic area and mechanical stretching are considered possible causes of early SMVT, whereas after the first 48 hours, the presence of infarct scar tissue is the likely mechanism.

In conclusion, both early and late SMVT are thus markers of extensive myocardial damage and independent predictors of short-term mortality. No long-term mortality studies were identified.

Atrioventricular conduction blocks

Haim et al13 find an incidence of 7.4% of high-degree atrioventricular conduction block (HAVB), defined as second or third degree atrioventricular conduction block, in 5839 patients with non–Q wave acute myocardial infarction (NQMI) from the SPRINT registry. High-degree atrioventricular conduction block conferred higher 24-hour mortality (15.5% vs 4%) and overall inhospital mortality (42% vs 10% without HAVB) and remained independent predictor of inhospital mortality (OR 5.1, 95% CI 2.1-11.9) after multivariate analysis. Similar conclusions were reported also by Berger et al14 in TIMI II trial, by Abidov et al15 in ARGAMI-2 trial, and for 2-year mortality as reported by Archbold et al16 in a study of 1225 patients.

On the other hand, Haim et al13 reported no difference in 1-year mortality (8% in all patients) and no significant statistical difference at 5 years (35% vs 27% without HAVB). The difference between the report from Haim et al13 versus the reports from Berger et al,14 Abidov et al,15 and Archbold et al16 can be explained by the use of different selection criteria (Q-wave acute myocardial infarction (QMI) vs STEMI).

In conclusion, HAVB has been demonstrated as an independent risk factor for short-term mortality, whereas its influence on long-term mortality is controversial.

Bundle-branch blocks

Of the 297 832 patients with AMI from the NRMI,17 6.7% presented with LBBB and 6.2% with right bundle-branch block (RBBB). The authors noted that the patients with bundle-branch block (BBB) received less evidence-based treatment (aspirin and β-blockers), whereas they were older and had more comorbidities (including congestive heart failure). The inhospital mortality after multivariate analysis was increased in both patients with LBBB (OR 1.34, 95% CI 1.28-1.39) and patients with RBBB (OR 1.64, 95% CI 1.57-1.71). New-onset BBB, with an overall incidence of 23.6%, was also evaluated in 681 patients from TAMI-9 and GUSTO-I trials, and the authors18 concluded that persistent, rather than transient, BBB remains predictive of higher 30-day mortality (19.4% vs 5.6%).

A study of 932 patients with Q-wave anterior AMI and poor ejection fraction by Ricou et al19 and another study of 681 patients with AMI by Moreno et al20 reported that new-onset nontransient RBBB was an independent predictor for both inhospital (22.9% vs 7.9% without RBBB) and 1-year mortality (40.5% vs 12.3% without RBBB) after multivariate analysis (OR not reported). An independent association was not found by Archbold et al16 for 6-month mortality (hazard ratio 1.18, 95% CI 0.63-2.21) in all RBBB in a nonselected population.

Three studies on LBBB have reported a higher mortality after multivariate analysis: GRACE registry2 (11 389 patients with ACS) for inhospital (OR 1.6, 95% CI 1.1-2.31), Archbold et al16 (1220 patients with AMI) for 6-month (hazard ratio 2.89, 95% CI 1.63-5.11), and Cannon et al21 et al from TIMI II (1416 patients with unstable angina or (NQMI) for 1-year mortality (OR 2.8, 95% CI 1.81-4.32).

In conclusion, both RBBB and LBBB independently predict poor short-term outcome; whereas LBBB is also an independent risk factor for increased long-term mortality, RBBB is not, with the exception when new onset and persistent.19

Q-wave AMI

In a multicenter study of 4202 patients, Chow et al22 reported higher inhospital mortality with QMI, and similar reports were provided by Behar et al23 in 580 patients with NQMI representing 14% of total patients with AMI from the SPRINT registry. Birnbaum et al24 reported the presence of abnormal Q waves in at least 2 leads with STE among 38.9% of 2370 patients with AMI, a finding associated with higher age and multiple comorbidities. It independently predicted higher inhospital mortality (OR 1.61, 95% CI 1.04-2.49), similar to reports from GRACE registry2 (OR 1.3, 95% CI 1.1-1.63) in patients with ACS.

Both Behar et al23 and Birnbaum et al24 report that QMI was not found to be a predictor of 1-, 5-, or 10-year mortality.

In conclusion, the presence of Q waves leads to higher short-term mortality but no independent influence on longer-term outcome.

QRS duration

Hathaway et al4 determined that QRS duration (QRSD) ≥100 milliseconds (OR 1.08, 95% CI 1.03-1.13) and QRS <50 milliseconds (OR 0.61, 95% CI 0.43-0.86) were independent predictors of 30-day mortality in 34 166 patients with STEMI from GUSTO-I.

Brilakis et al25 reported that in patients with non-ST segment elevation myocardial infarction, inhospital, 1-, 3-, and 5-year mortality were higher with a QRSD ≥ 100 milliseconds (16% vs 5%, 25% vs 11%, 34% vs 17%, 48% vs 26%, respectively), whereas patients with STEMI had similar survival curves regardless of their QRSD. After adjustment for age, sex, Killip class, and HR, a QRSD of ≥100 milliseconds remained an independent risk factor for both inhospital (RR 4.22, 95% CI 1.81-10.39) and long-term mortality (RR 1.63, 95% CI 1.11-2.40).

The authors suggested that a long QRSD adversely affected survival possibly because of its coexistence with a higher incidence of heart failure, a larger number of stenosed coronaries, an increased arrhythmia risk, or a combination of the previous.

In conclusion, a long QRSD is an independent predictor of both short- and long-term outcome.

ST-segment elevation

The following ST-segment changes present on the baseline ECG in the patients with ACS from GRACE registry2 were independent risk factors for higher inhospital mortality: any ST-segment deviation (OR 1.8, 95% CI 1.33-2.40), anterior STE (OR 1.7, 95% CI 1.3-2.2), and anterior STD (OR 1.5, 95% CI 1.1-1.92). The same findings were reported in a study correlating outcome with the number of leads showing STE in 7755 patients from GISSI-2 registry26 (Figure 1), in a report from GUSTO-IIb27 on 12 142 patients on 30-day mortality in patients with STE (OR 2.59, 95% CI 1.47-2.92), and by Chow et al.22

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Figure 1. A, Inhospital mortality (n = 7755).26 B, Six-month mortality (n = 2719).28 C, Thirty-day mortality (n = 12 142).27 D, One-year mortality (n = 1588).33

Six-month mortality was studied in 2719 patients recruited for in the InTIME II study28 (Figure 1). Patients had maximum STE measured at 90 minutes postthrombolysis and were stratified into 3 risk groups based on the amount of STE and the presence or absence of BBB, showing higher mortality with higher degree of STE.

In conclusion, a higher STE confers a higher short-term mortality, but for long-term outcome, only STE of >2 mm associated with BBB was an independent predictor.

ST-segment depression

In 9461 patients with ACS from PURSUIT,29 the presence of STD conferred higher 30-day mortality (5.1% vs 2.1% no STD), which remained significant after multivariate analysis (OR 1.80, 95% CI 1.40-2.33), and similar findings were reported in GUSTO-IIb27 (OR 2.07, 95% CI 1.82-3.69) and by Mahon et al.30 Birnbaum et al31 reported on 1321 patients (77% males) enrolled in GUSTO-I that patients with a higher sum of STD in the lateral leads (V4-V6) had higher inhospital mortality (OR 2.78, 95% CI 1.26-6.13) after multivariable adjustment. Peterson et al32 examined 16 521 GUSTO-I patients with inferior AMI finding that the sum of STD remained the most significant independent ECG predictor for 30-day mortality (OR not reported).

Kaul et al33 assessed the impact of STD on long-term mortality in 1588 patients from the PARAGON-A trial and validated the predictive model on the GUSTO-IIb population. Patients with greater depths of STD (present in at least 2 continuous leads) had higher 1-year mortality rates (Figure 1).

In conclusion, both STD and sum of STD remain strong independent predictors of both short- and long-term mortality, possibly stronger than STE.

ST-segment resolution

Corbalan et al39 reported in a study of 967 patients that early (within 2 hours after thrombolysis) ST-segment resolution (STR) of >50% of the initial deviation is a strong but not independent predictor of inhospital mortality (univariate OR 0.33, 95% CI 0.21-0.50). In study of 2719 patients from the InTIME II trial, Schroeder et al28 reported similar findings for inhospital mortality but states that any level of the sum of STR (low, partial, or complete) independently predicts 6-month mortality compared with no STR (OR not reported).

In GUSTO-III trial,34 complete STR at 90 minutes was found to be strong predictor of 30-day and 1-year mortality (Figure 2) (OR not reported). The ISAM trial35 also reports complete early STR as an independent predictor of both short- and long-term mortality (Figure 3).

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Figure 2. Early and late ST-segment resolution and mortality by Anderson34 (n = 1741).

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Figure 3. Compared mortality in no STR versus complete STR by Schroeder et al37 (n = 1741).

Patients from the GISSI-2 trial36 who reached an STR of >50% by 4-hour postthrombolysis had a lower 30-day (RR 0.46, 95% CI 0.37-0.57) and 6-month mortality (RR 0.58, 95% CI 0.48-0.70). Similar results were reported from the INJECT trial37 where the absence of STR (vs complete STR) was a strong independent predictor of 35-day mortality (OR 6.9, 95% CI 3.8-12.5). In the same article from the ISAM35 trial, Kaplan-Meier survival curves for anterior and inferior AMI showed that patients without STR had a significant increased mortality up to 6 years after AMI, similar to findings by French et al.38

In conclusion, a significant STR, regardless whether early or late, improves both long- and short-term survival after AMI.

T-wave inversion

In a study of 967 patients with new QMI, Corbalan et al39 assessed the presence of early TWI (first 24 hours after thrombolysis) in the infarct-related ECG leads together with other potential predictors for inhospital mortality and found it to be an independent protective factor (OR 0.29, 95% CI 0.11-0.68). In a substudy of 12 142 patients with AMI from GUSTO-IIb,27 the incidence of TWI was 22%; STE, 28%; STD, 35%; and STE with STD, 25%. The multivariate analysis for 30-day and 6-month mortality showed TWI conferring better protection than STE and STD (Figure 4). Herz et al40 used different methods to classify 2853 patients with STEMI based on the presence of negative T waves (NTWs) in patients treated within 2 hours after symptoms onset versus after 2 hours. They reported higher inhospital mortality when patients with NTW were treated after 2 hours compared to no NTW (OR 1.86, 95% CI 1.07-3.25), but not when treated within 2 hours (mortality 0/52 patients).

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Figure 4. Thirty-day (A) and six-month mortality ( (n = 12 142).27

In conclusion, TWI is a strong independent negative risk factor for short-term outcome in STEMI (especially when thrombolysis is given within 2 hours of symptoms onset), whereas in NSTEMI, it is an independent risk factor for both short- and long-term poor outcome.

Myocardial infarction location

In a study on 7755 patients enrolled in GISSI-2, Fresco et al26 found that anterior infarction was an independent risk factor for increased inhospital mortality (OR 2.1, 95% CI 1.5-2.9). Lee et al3 also report higher overall 30-day mortality with anterior versus nonanterior location (OR 1.55, 95% CI 1.43-1.68) in 41 021 patients with STEMI from GUSTO-I study. The lowest 30-day mortality occurred with inferior location versus noninferior (OR 0.67, 95% CI 0.50-0.90) after multivariate analysis.

In a report of 2719 patients by Schroeder et al,28 anterior AMI remained an independent risk factor correlating with increased 180-day mortality (OR not reported). In a study on 610 patients enrolled in SPRINT41 with their first non-QMI, 248 (40.6%) had anterior and 327 (53.6%) had inferior or lateral infarction. Inhospital, 1-year, and 5-year mortality were 15% versus 10% (anterior vs inferior or lateral), 12% versus 6%, and 36% versus 22%, respectively. After correction for age, sex, prior hypertension (HTN), diabetes mellitus and angina, and therapy, anterior infarction location was no longer an independent predictor, but small sample size limits the ability to show this effect.

The only specific AMI locations for which our search found relevant articles are anterior and inferior, the first location reported as independent risk factor and the latter reported as negative risk factor for short-term mortality. For long-term mortality, the reports are not as well documented, but the trend is similar as for short-term mortality.

Discussion

The best predictors of increased short-term mortality identified by our review are ventricular tachycardia, ST-segment deviations, high-degree atrioventricular block, and long QRSD. For long-term mortality, ST-segment deviations and LBBB are the most significant independent risk factors. A summary of the independent risk factors for short- and long-term mortality is depicted in Figure 5 and Figure 6. For calculating the OR for each ECG parameter, the referent was the absence of the respective parameter from the admission ECG. In the absence of a true comparison of different OR that requires all parameters to be studied in the same population, a simulated head-to-head comparison is offered based on significant similarities among the studied populations due to consistently applied inclusion criteria.

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Figure 5. Short-term mortality overview. AV, Atrioventricular.

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Figure 6. Long-term mortality overview.

Our review also identified several ECG parameters as markers of mortality, which did not reach independent predictor status after multivariate analysis. High-degree atrioventricular block was an independent predictor of increased short-term but controversial on long-term mortality. ST-segment depression and anterior AMI location were both reported as independent risk factors for short-term but not for long-term mortality. For certain ECG parameters included in our review, we were able to identify possible knowledge gaps that could be addressed in future studies. We did not identify any study to assess the predictive power on long-term mortality of the normal admission ECG and baseline AF. It is possible that other ECG parameters have been researched but were not identified at the time of our literature search; some of them could be of important prognostic value.

In conclusion, most of the studied ECG abnormalities that accompanied an AMI presentation, with the exception of TWI and STR, are associated with various levels of increased mortality risk. Their presence should help the clinician identify the patients who are at the highest risk and will benefit most from maximized monitoring and evidence-based therapies. To help further sort out the numerous ECG findings, so far individually researched, a simultaneous analysis on multiple ECG parameters (possibly including novel ones) in a representative population is clearly needed.

Limitations

The current review article has inherent limitations because of its nature; occasionally, the original studies included have slightly different inclusion criteria, the populations researched had different baseline characteristics and treatment, and secular trends could have affected enrollment and management. The authors attempted to overcome these limitations by providing a comprehensive, focused, and distinctive analysis of highly selected original articles from the modern revascularization era of AMI therapy.

The authors thank Dean E. Smith, PhD, University of Michigan, for his timely and broad statistical support.

References

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[AZCEP]

So to get these kinds of results the facilities have to believe that we know what we are doing individually.

What would be the best way to get this message across? We all have worked with providers of all levels that we wouldn't let treat a sick cockroach, much less a human being, so how do we go about convincing the receiving physicians that, as a group, we can make this determination without them?

This is most definitely a serious question, because we are having this issue here locally. Perhaps I'm guilty of thinking locally and acting globally, but if anyone has suggestions, I'm willing to listen.

[Ace844]

So to get these kinds of results the facilities have to believe that we know what we are doing individually.

What would be the best way to get this message across? We all have worked with providers of all levels that we wouldn't let treat a sick cockroach, much less a human being, so how do we go about convincing the receiving physicians that, as a group, we can make this determination without them?

This is most definitely a serious question, because we are having this issue here locally. Perhaps I'm guilty of thinking locally and acting globally, but if anyone has suggestions, I'm willing to listen.

"AZCEP,"

Anecdotally I've found exposure and time together in a clinical environment makes the difference. This usually gets resisitance though from the EMS providers and soemtimes companies-municipalities as it requires them to debate issues like pay vs your own time and actually having to put forth effort above and beyond what time are we getting breakfast at the start of shift. Furthering this thought if you sit down with the docs and work out an outline whereby you all could spend time together clinically, them in the field on calls and you guys in the hospital I think that you'll find once they get to know the knowledge base, experience, etc... that they will be more comfortable with your local EMS clinicians. Food for thought and this is a potentially daunting migraine inducing task which will ultimately be decided by a combo of effort and politics.

ACE844

[AZCEP]

I hope GA is reading.

Yet another way Ace has suggested to improve an EMS system. Let's see, breakfast for 70 physicians, yeah, the budget should cover that. Somebody get IHOP on the phone!