Ver el código de «STEMI equivalents»

==Background==
*STEMI typically defined by<ref>ECC Committee, Subcommittees and Task Forces of the American Heart Association.. 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care — Part 8: Stabilization of the Patient With Acute Coronary Syndromes. Circulation. 2005. 112 (24_suppl):IV–89–IV–110. 2005.</ref>:
**≥1 mm (0.1 mV) ST segment elevation in limb leads
**≥ 2 mm ST segment elevation in precordial leads
**Findings present in at least 2 anatomically contiguous leads
*Several variations from the classic STEMI ECG changes are similarly concerning and considered 'STEMI equivalent'

==STEMI Equivalents==
===Posterior MI===
*RCA (90%), LCA (10%)
*12-Lead ECG findings<ref>Van Gorselen EO, et al. Posterior myocardial infarction: the dark side of the moon. Neth Heart J. 2007; 15:16-21.</ref>
**ST-segment depression (horizontal >> downsloping/upsloping)
**Prominent and broad R wave (>30ms)
**Relative tall R waves in precordial leads (may find R = S amplitude in V1)
**R/S wave ratio >1.0 in lead V2
**Prominent, upright T wave
**Combination of horizontal ST-segment depression with upright T wave
*Posterior ECG or 15-lead ECG may be helpful
**V7: Left posterior axillary line along the 5th ICS
**V8: Tip of the left scapula line along the 5th ICS
**V9: Left paraspinal area line along the 5th ICS
*Posterior ECG findings
**≥0.5 mm ST-segment elevation
[[File:Posterior MI.jpg|350px]]

===LMCA Occlusion===
*Seen with left main artery lesion<ref>Hennings JR and Fesmire FM. A new electrocardiographic criteria for emergent reperfusion therapy. Am J Emerg Med. 2012; 30(6):994–1000.</ref>
*Also reported in proximal LAD lesions and severe multivessel coronary artery disease
*12-Lead ECG findings
**ST elevation in aVR ≥ 1mm
**ST elevation in aVR ≥ V1
**ST depression typically seen in lateral 
[[File:AVR.jpg|350px]]

===[[De Winter’s T Waves]]===
*Suggests proximal LAD lesion
*12-Lead ECG findings<ref>de Winter R, et al. A new ECG sign of proximal LAD occlusion. NEJM. 2008; 359:2071–2073.</ref>
**Precordial ST-segment depression at the J-point
**Tall, peaked, symmetric T waves in the precordial leads
**Lead aVR shows slight ST-segment elevation in most cases
[[File:Dewinter.jpg|350px]]

===[[Sgarbossa's Criteria]]===
*Used to identify STEMI in the setting of LBBB or pacemaker
*Original Criteria<ref>Sgarbossa E, et al.. "Electrocardiographic diagnosis of evolving acute myocardial infarction in the presence of left bundle-branch block. GUSTO-1 (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries) Investigators". NEJM. 1996; 334(8):481-7.</ref>
**≥3 points = 98% probability of STEMI
**ST elevation ≥1 mm in a lead with upward (concordant) QRS complex - 5 points
**ST depression ≥1 mm in lead V1, V2, or V3 - 3 points
**ST elevation ≥5 mm in a lead with downward (discordant) QRS complex - 2 points
*Smith's modification<ref>Smith, S, et al. Diagnosis of ST-Elevation Myocardial Infarction in the Presence of Left Bundle Branch Block With the ST-Elevation to S-Wave Ratio in a Modified Sgarbossa Rule. 60(6):766-776.</ref>
**Changes the 3rd rule of original Sgarbossa's Criteria to be ST depression '''OR''' elevation discordant with the QRS complex and with a magnitude of at least 25% of the QRS increases Sn from 52% to 91% at the expense of reducing Sp from 98% to 90%[
[[File:Sgarbossa.jpg|350px]]

===[[Wellens’ Syndrome]]===
*[[ECG]] findings in absence of chest pain, but with recent cardiac chest pain symptoms
*Represents critical stenosis of the LAD
*Requires PCI in the next 24-48hr (may evolve more rapidly - observe with serial ECGs)
*12-Lead ECG findings<ref>Rhinehardt J, et al. Electrocardiographic manifestations of Wellens' syndrome. Am J Emerg Med. 2002; 20(7):638-43.</ref>
**Deeply-inverted or biphasic T waves in V2-3
**Isoelectric or minimally-elevated ST segment (<1 mm)
**Absent precordial Q waves with preserved R waves
*Two T wave characteristics:
**Type A: Biphasic pattern - 25% - Biphasic T-waves
**Type B: Inversion pattern - 75% - Deeply inverted and symmetric T-waves
[[File:Wellens.jpg|350px]]

==No Longer STEMI Equivalents==
===[[LBBB|New LBBB]]===
*New LBBB alone is no longer a reason to activate the cath lab<ref>Jain  S, et al. Utility of left bundle branch block as a diagnostic criterion for acute myocardial infarction. Am J Cardiol. 2011; 107:1111-1116.</ref>
*However, careful workup for ACS should be taken for symptomatic patients with LBBB
*12-Lead ECG findings
**QRS > 0.12 in limb leads
**Leads
***Large and wide R waves — leads I, aVL, V5, and V6
***Small R wave followed by deep S wave —leads II, III, aVF, V1–V3
[[File:LBBB.jpg|350px]]

==External Links==
*[https://www.youtube.com/watch?v=JxPgcPEqI5k Amal Mattu ECG Case: April 29 2012]

==See Also==
*[[ST-segment elevation myocardial infarction]]
*[[Acute Coronary Syndrome (Main)]]
*[[Chest pain]]
*[[ECG (Main)]]

==References==
<references/>

[[Category:Cardiology]]