BACKGROUND:

1. 209 STEMI PATIENTS (FROM EMR) EKG CHANGES EARLY DETECTION? PROCEDURAL SUCCESS Q WAVES STE DEGREE LEADS INVOLVED MORPHOLOGY EKG CHANGES EARLY DTBTIME? ED TO CATH TIME >250 STEMI PTS (2004-2005) TRANSFERPATIENTS 209 STEMI PATIENTS (FROM EMR) NOT DIRECTLY TO CATH LAB FROM ED COMPARATIVE ANALYSIS OF MORPHOLOGICAL EKG CHANGES AND DOOR-TO-BALLOON TIME IN STEMI Mercy P. Chandrasekaran, Jeffrey Cook, Raj Marok, Carlos Arrieta-Garcia, Kathleen Magurany, Peter Stecy, Lloyd W. Klein Departments of Internal Medicine & Cardiology BACKGROUND: RESULTS: RESULTS: RESULTS: • Presence of reciprocal changes on EKG resulted in earlier mean DTB (110 vs 143 mins, p<.001) as well as earlier mean door-to-cath (DTC) times (66 vs 104 mins, p=.0001). • The involvement of >1 ischemic distribution resulted in earlier DTB (82 vs 106 mins, p= 0.046) and DTC (71 vs 88 mins, p=0.0001). • Pts presenting with inferior/posterior MI compared with other distribution had earlier DTC (77 vs 87 mins, p=0.0001). • Pts with DTB<90 min demonstrated greater mean STE than those with DTB>90, 3.0 +/- 1.5 vs 2.4 +/- 1.4, (p<0.01). • Pts with DTB<90 were also more likely to have had inferior/posterior MI than those with DTB>90, (67.2% vs 45.1%, p=.01), and reciprocal depression (71.6% vs 43.7%, p<.01). • When adjusted for other variables, reciprocal depression remained a strong predictor of DTB<90, HR 3.4 (1.76-6.98, p=.001) [SEE MULTIVARIATE TABLE] • History, clinical presentation, and EKG should be used in combination for earliest possible detection of STEMI (1) . • Early detection is crucial to decrease mortality in by decreasing door-to-balloon (DTB) time (2). • Rapid and accurate EKG diagnosis of MI is a challenge (3) is often reader dependent, especially as changes may be dynamic. • Reciprocal ST segment depression, convex morphology, and degree/ number leads elevated, have been reported to assist in the differentiation of non infarction causes of STE from AMI-related STE (4). Graph 2: Inferior MI and Reciprocal Depression by DTB Group Key: Green bars indicate inferior MI, blue dots indicate reciprocal depression and *Asterisk indicates statistical significance when compared with group DTB>90 Graph 1: DTB Time and Mortality Rathore S S et al. BMJ 2009;338:bmj.b1807 CONCLUSIONS: • Earlier DTB were achieved in patient with EKG’s presenting with: • 1. reciprocal changes • 2. inferior/posterior MI • 3. greater degrees of ST elevation and distribution • This indicates that some EKG morphologies increase early recognition of STEMI. • On the other hand, Anterior MI was not as quickly recognized. • These findings raise the questions: • 1. What is the value of EKGs in early detection of STEMI ? • 2. How much do physician deficiencies in interpretation compromise early detection of STEMI? • 3. What steps can be taken to improve interpretation? METHODS: REFERENCES: 1.Braunwald E, et al. Unstable angina: diagnosis and management. 2. Rathore S, et al BMJ 2009;338: b1807 3. Brady WJ et al Acad Emerg Med. 2001 Apr;8(4):349-60. Electrocardiographic ST-segment elevation: correct identification of acute myocardial infarction (AMI) and non-AMI syndromes by emergency physicians. 4. Brady WJ et al Electrocardiographic ST segment elevation: a comparison of AMI and non-AMI ECG syndromes. 5. www.projectupstart.com 6. Zimetbaum PJ, Josephson ME., 935. Use of the electrocardiogram in acute myocardial infarction. N Engl J Med 2003;348:934 7. IC Rokos et al Am Heart J. 2010 Dec;160(6):995-1003, 1003.e1-8 8. ACC/AHA STEMI guidelines 9. Jacobs A, et al. Circulation. 2007;116:217.