Is He Having The Big One? Sirous Partovi, M.D. Department of Emergency Medicine TTUHSC, El Paso ECG #1- 68 year old with chest pain for 3 days ECG #2- 66 year old man with 1 hour history of chest pressure ECG #3- 39 year old AAM with chest pain, PMH HTN ECG #4 - 62 year old with profuse diaphoresis and vomiting ECG #5-72 year old male- PMH: CRF,a-fib presents with generalized weakness for 1 hour. ECG #6- 45 year old female with onset of chest discomfort 2 hours ago – PMH ?Cancer ECG #7 – 50 year old man with crushing substernal chest pain for 30 minutes ECG #8- 72 year old female with history of HTN found unconscious ECG #9- 67 year old man with PMH of MI in respiratory failure due to acute CHF ECG #10- Chest pain radiating to the jaw in a 41 year old woman Objectives Understand the etiology of chest pain Distinguish between Acute Coronary events requiring thrombolysis and those that do not. Recognize the more common conditions that may cause a pseudo-infarction pattern on ECG. Chest Pain 2% of all ED visits 10-20% are diagnosed with AMI 1.7 million admissions to hospitals annually $5 Billion spent on admitted patients which AMI was subsequently ruled out in Chest Pain- AMI 1.1 million cases of AMI annually 50% present to EDs 2%-8% rate of misdiagnosis 11,000 missed diagnosis of MI per year 20% of money awarded in malpractice cases Differential Diagnosis of Chest Pain Cardiac Non-ischemic Ischemic Pericarditis Angina Unstable AMI angina Aortic dissection Valvular Myositis Differential Diagnosis of Chest Pain Non-cardiac Gastroesophageal Causes GERD Esophageal spasm PUD Boerhaave’s Syndrome Cholecystitis Differential Diagnosis of Chest Pain Non-cardiac Non-gastroesophageal Pneumothorax Pulmonary embolism Musculoskeletal Somatoform disorders Chest Pain-Diagnosis History and Physical ECG Cardiac serum markers AMI- World Health Organization (WHO) Definition A combination of two of three characteristics: Typical symptoms (i.e., ischemic-type chest discomfort) A rise and fall in serum cardiac markers Typical ECG pattern involving the development of Q waves Acute MI - History 70%-80% present with ischemic type CP Less than 25% of patients admitted to hospital with ischemic-type CP are diagnosed with AMI Unusual symptoms for AMI Elderly Women Diabetics Features of H&P That Increase the Probability of AMI Panju et al, JAMA. 1998;280:1256-1263 History and Physical Chest pain radiating to both arms Third heart sound Hypotension Chest pain radiating to right shoulder LR 7.1 3.2 3.1 2.9 Likelihood Ratio Positive LR Odds that a patient with a positive test result has the target disorder Pos LR= Sensitivity/(1-Specificity) Negative LR Odds that a patient with a negative test result has the target disorder Neg LR= (1-Sensitivity)/Specificity Historical Features That Decrease the Probability of AMI Panju et al, JAMA. 1998;280:1256-1263 Quality of Chest Pain Pleuritic Sharp or stabbing Positional Reproduced by palpation LR 0.2 0.3 0.3 0.2-0.4 ECG evolution in Q-wave Myocardial Infarction Tall peaked T-waves ST-segment elevation Appearance of abnormal Q wave Decrease of ST-segment elevation with the beginning of T-wave inversion Isoelectric ST-segment with symmetrical T-wave inversion Tall T- Waves The earliest sign of AMI Due to subendocardial ischemia Within minutes or hours after the onset of chest pain Transient Most ECGs fail to show this pattern ECG evolution in Q-wave Myocardial Infarction Tall peaked T-waves ST-segment elevation Appearance of abnormal Q wave Decrease of ST-segment elevation with the beginning of T-wave inversion Isoelectric ST-segment with symmetrical T-wave inversion ST-Segment Elevation The most common early ECG sign STE - specificity 91% , sensitivity 46% Mortality increases with the number of ECG leads showing ST elevation STE decreases in the first 7-12 hours STE resolves within 2 weeks in 90% of IWMI, but only in 40% of anterior MI Reciprocal ST-Segment Depression Seen in up to 82% Marked early, 50% resolve within 24 hours Due to reciprocal electrical alteration Increases specificity of AMI to 99% Seen in 72% of IWMI Indicative of: Larger AMI Lower ventricular ejection fraction Higher mortality ECG evolution in Q-wave Myocardial Infarction Tall peaked T-waves ST-segment elevation represents a stage beyond ischemia -i.e. injury Appearance of abnormal Q-wave Decrease of ST-segment elevation with the beginning of T-wave inversion Isoelectric ST-segment with symmetrical T-wave inversion Abnormal Q-Waves Most commonly presents while STsegment still elevated 12-20% of Q-waves do not persist CHF is more common with persistent Q-waves ECG evolution in Q-wave Myocardial Infarction Tall peaked T-waves ST-segment elevation Appearance of abnormal Q wave Decrease of ST-segment elevation with the beginning of T-wave inversion Isoelectric ST-segment with symmetrical T-wave inversion ECG evolution in Q-wave Myocardial Infarction Tall peaked T-waves ST-segment elevation represents a stage beyond ischemia -i.e. injury Appearance of abnormal Q wave Decrease of ST-segment elevation with the beginning of T-wave inversion Isoelectric ST-segment with symmetrical T-wave inversion Criteria for Thrombolysis ST elevation (greater than 1 mm in two or more contiguous leads), time to therapy 12 hours or less, age less than 75 years. Bundle branch block (obscuring ST-segment analysis) and history suggesting acute MI. AMI Diagnosis- ECG Factors Influencing ECG Interpretation Clinical observation of the patient Knowledge of clinical data Training and experience of interpreter AMI Diagnosis- ECG Gjorup et al, J Intern Med. 1992; 231: 407-412 16 IM residents read 107 ECGs Looking for signs indicative of AMI Disagreement in 70% of the cases AMI Diagnosis- ECG Willems et al, NEJM. 1991; 325:1767-1773 8 cardiologists interpreted 1220 ECGS High interobserver agreement - of 0.67 125 ECGs read twice Different diagnosis for 10%-23% of ECGs AMI Diagnosis- ECG Massel et al. Am Heart J. 2000;140:221-6 3 cardiologists - 75 ECGs 2 occasions (within 7 days) First reading: Presence or absence of thrombolysis eligibility criteria Second reading: criterion 1 plus the subjective opinion that the changes represented acute transmural injury AMI Diagnosis- ECG Interobserver variability in thrombolytic therapy eligibility Is there 1 mm ST elevation? Does this represent an AMI? Agreement kappa Agreement kappa Rater 1 vs 2 93.3 86.2 94.7 88.2 Rater 2 vs 3 88.0 75.8 94.7 88.0 Rater 1 vs 3 86.7 72.9 94.7 88.2 Overall 78.2 88.5 Errors in AMI ECG of a patient who is otherwise eligible may be incorrectly interpreted as being nondiagnostic ST-segment elevation may be erroneously interpreted as suggesting an AMI, resulting in the inappropriate overuse of thrombolysis Errors in AMI – Missed Diagnosis ECG of a patient who is otherwise eligible may be incorrectly interpreted as being nondiagnostic ST-segment elevation may be erroneously interpreted as suggesting an AMI, resulting in the inappropriate overuse of thrombolysis Errors in AMI - Missed Diagnosis McCarthy et al, Ann Emerg Med.1993;22:5795-82 Rate of missed AMI among 6 NE hospitals 1050 patients with AMI 1.9% misdiagnosed 25% of the patients with missed AMI had STE of at least 1 mm Death or severe complications in 25% of pts Errors in AMI - Missed Diagnosis Pope et al, NEJM 2000;342:1163-70 10,689 patients, 10 hospitals (ACI-TIPI trial) 17% had acute cardiac ischemia (ACI) 8% AMI 9% UA 6% stable angina 21% other cardiac diagnosis 55% noncardiac diagnosis Errors in AMI – Missed Diagnosis Pope et al Of 894 AMI patients, 19 (2.1%) was missed 8 (47%) had one of the following ECG readings: LVH, LBBB, BER, pericarditis 7 (41%) minor ST segment abnormality with <1mm of ST segment deviation 14 of 19 had NQWMI Errors in AMI – Missed Diagnosis Brady et al, AEM, April 2001 11 ECGs with STE 45 yo male with HTN, DM and chest pain 458 EPs Errors in AMI – Missed Diagnosis Brady et al, AEM, April 2001 Overall rate of correct Errors in AMI ECG of a patient who is otherwise eligible may be incorrectly interpreted as being nondiagnostic ST-segment elevation may be erroneously interpreted as suggesting an AMI, resulting in the inappropriate overuse of thrombolysis Errors in AMI - Over Diagnosis Lee et al, Ann Int Med 1989;110:957-62. No AMI in 25% of patients with acute chest pain and ST-segment elevation For every 8 patients appropriately treated with a thrombolytic agent 1 or 2 will be treated unnecessarily Errors in AMI-Over Diagnosis Sharkey et al, Am J Cardiol 1994;73:550-3 93 patients with chest pain receiving thrombolytic therapy, AMI did not occur in 10 (11%) LVH- 30% BER- 30% IVCD- 30% Impact of Errors Bleeding consequences Life-threatening bleed- 0.4% Moderate bleed- 5% Not treating an eligible thrombolysis candidate Financial consequences Missed AMI is the leading cause of malpractice loss in the ED setting Causes of ST Segment Elevation Cardiac Acute myocardial infarction Variant (Prinzmetal's) angina Acute pericarditis Left ventricular aneurysm Left ventricular hypertrophy Bundle branch blocks Benign Early repolarization Causes of ST Segment Elevation Metabolic Hyperkalemia Hypothermia (Osborne or "J" waves) Hyperventilation Causes of ST Segment Elevation Miscellaneous Acute abdominal disorders (pancreatitis, cholecystitis, peritonitis) Central nervous system hemorrhage Medications (type I anti-arrhythmic agents, isoproterenol) Body habitus Idiopathic Localization of Acute MI LOCATION ECG LEADS INVOLVED Anteroseptal V1, V2 Anterior V2, V4 Anterolateral Extensive Anterior Inferior PROBABLE ARTERY INVOLVED Proximal LAD septal perforator LAD or its branches V4- V6, I, aVL Mid LAD or circumflex V1-V6 Proximal LAD II,II,aVF RCA, circumflex, distal LAD High lateral I, aVL Circumflex or branch of LAD Posterior V1, V2 Posterior descending Right ventricle V1, rV3- rV4 RCA ECG #1- 32 year old with chest pain at a party Anterolateral MI Anterolateral MI - II Anterolateral MI - III 65 year old with acute chest pain Anterior MI Acute Anterior MI Acute Anteroseptal MI Acute Anterior MI Acute Anteroseptal MI 53 year old with severe light headedness, nausea, diaphoresis, and upper abdominal pain. Bloods pressure 85/palp. Acute Inferoposterior MI R R R R R Acute Lateral MI ECG #4 - 62 year old with profuse diaphoresis and vomiting ECG #7 – Acute Posterior MI - Old inferior MI Inferior MI (MR# 866159) -77 year old male with chest pain and palpitation Anterior MI LVH with ST-T Wave Changes Left Ventricular Hypertrophy Definition ECG diagnosis: based on the increase of the QRS voltage Possible LVH - only voltage evidence of LVH Definite LVH - voltage evidence of LVH associated with ST-T wave changes (strain) Strain pattern – characterized by downsloping ST depression with asymmetric, biphasic, or inverted T wave (occurs in 70% of cases) LVH With Strain and CAD 50% prevalence of demonstrated CAD in asymptomatic hypertensive patients with LVH and strain vs. 4% general population 60% of patients with LVH and strain had reversible perfusion defects on Thallium scintigraphy LVH ECG is 93-96% specific and 12-29% sensitive in diagnosing LVH Echocardiography- 86% specificity and 100% sensitivity for diagnosis of LVH LVH Otto LA et al, Ann Emerg Med 1994;23:17-24 Prehospital study of adult chest pain patients with STE Majority did not have AMI LVH and LBBB were most common LVH Brady WJ, J Emerg Med STE resulted from AMI in only 15% LVH was the most frequent cause of this STE (30%) LVH Larsen et al, J Gen Intern Med 1994;9:666-673 10% of patients diagnosed in the ED with acute ischemic heart disease have LVH Only 26% of these patients were found to have unstable angina or AMI Physicians incorrectly interpreted the ECG more than 70% of the time LVH by Voltage Only Cornell Criteria- RaVL+SV3 >24 mm in males >20 mm in female LVH by Voltage Only Other commonly used voltage-based criteria Precordial leads (one or more) RV5 or V6 + SV1 >35 mm if age> 30 years >40 mm if age 20-30 years >60 mm if age 16-19 years Maximum R wave + S wave in precordial leads >45 mm RV5 > 26 mm RV6> 20mm LVH by Voltage Only Other commonly used voltage criteria Limb leads (one or more) RaVL >12 mm RI + SII >26 mm RI >14 mm SaVR >15 mm RaVF >21 mm LVH by Voltage RV5+SV1=43mm RV5= 37mm LVH by Both Voltage and ST-T Segment Abnormalities Voltage criteria for LVH ST-T segment abnormalities ST segment and T wave deviation opposite in direction to the major deflection of QRS ST segment depression in leads I, aVL, III, aVF +/- V4-V6 Subtle ST elevation (1-2 mm) in leads V1-V3 Inverted T waves in leads I, aVL, V4-V6 Prominent or inverted U waves LVH by Both Voltage and ST-T Segment Abnormalities Voltage criteria for LVH ST-T segment abnormalities ST segment and T wave deviation opposite in direction to the major deflection of QRS ST segment depression in leads I, aVL, III, aVF +/- V4-V6 Subtle ST elevation (1-2 mm) in leads V1-V3 Inverted T waves in leads I, aVL, V4-V6 Prominent or inverted U waves LVH by Both Voltage and ST-T Segment Abnormalities Voltage criteria for LVH ST-T segment abnormalities ST segment and T wave deviation opposite in direction to the major deflection of QRS ST segment depression in leads I, aVL, III, aVF +/V4-V6 Subtle ST elevation (1-2 mm) in leads V1- V3 Inverted T waves in leads I, aVL, V4-V6 Prominent or inverted U waves LVH by Both Voltage and ST-T Segment Abnormalities Voltage criteria for LVH ST-T segment abnormalities ST segment and T wave deviation opposite in direction to the major deflection of QRS ST segment depression in leads I, aVL, III, aVF +/- V4-V6 Subtle ST elevation (1-2 mm) in leads V1-V3 Inverted T waves in leads I, aVL, V4-V6 Prominent or inverted U waves Romhilt and Estes LVH Point Score System QRS Voltage – 3 points for the presence of any 1 criteria R or S in limb leads 20 mm S in V1 or V2 30 mm R in V5 or V6 30 mm Typical ST-T repolarization abnormality Without digitalis – 3 points With digitalis – 1 point LAD - 30° or more – 2 points QRS duration 0.09 sec – 1 point ID V5-6 0.05 sec – 1 point LAE – 3 points LVH With ST-T Abnormalities S in aVR > 14mm R in I = 15mm RV5>26mm RV5+SV1=65mm R in aVL + S in V3 >24mm LVH With ST-T Abnormalities 34 year old AAM with chest pain-No PMH Benign Early Repolarization First described in 1936 by Shipley A normal variant- 1% general population Common in athletes BER-in adult ED chest pain patients ~13% BER is seen on ECGs 23-48% of adult ED chest pain patients who have used cocaine Benign Early Repolarization Mean age - 39 (16-80) Most commonly less than 50 years of age- older than 70 years(3.5%) Seen in men much more often than women ECG Criteria For BER Elevated take-off of ST segment at the J point Upward concavity of the initial portion of the ST segment Notching or slurring on downstroke of R wave Symmetric, concordant T waves of large amplitude Widespread or diffuse distribution of ST segment elevation on the ECG - most commonly in leads V2-V5, sometimes in inferior leads No reciprocal ST segment change relative temporal stability J point elevation- less than 3.5 mm ST segment appears as if it has been lifted evenly upward STE is less than 2 mm in 80-90% Only 2% of cases STE is greater than 5 mm. J point ECG Criteria For BER Elevated take-off of ST segment at the J point Upward concavity of the initial portion of the ST segment Notching or slurring on downstroke of R wave Symmetric, concordant T waves of large amplitude Widespread or diffuse distribution of ST segment elevation on the ECG - most commonly in leads V2-V5, sometimes in inferior leads No reciprocal ST segment change relative temporal stability Upward concavity ECG Criteria For BER Elevated take-off of ST segment at the J point Upward concavity of the initial portion of the ST segment Notching or slurring on downstroke of R wave Symmetric, concordant T waves of large amplitude Widespread or diffuse distribution of ST segment elevation on the ECG-most commonly in leads V2-V5, sometimes in inferior leads No reciprocal ST segment change relative temporal stability Tall symmetric T wave ECG Criteria For BER Elevated take-off of ST segment at the J point Upward concavity of the initial portion of the ST segment Notching or slurring on downstroke of R wave Symmetric, concordant T waves of large amplitude Widespread or diffuse distribution of ST segment elevation on the ECG - most commonly in leads V2-V5, sometimes in inferior leads No reciprocal ST segment change relative temporal stability Benign Early Repolarization (BER) Acute Pericarditis Acute Pericarditis Stage 1- Concave up ST segment elevation Stage 2- ST segment normal, flattening of the T waves Stage 3- T wave inversion without Q wave formation Stage 4- Normalization of ECG Acute Pericarditis- Other ECG Clues Sinus tachycardia PR depression early Low voltage QRS Electrical alternans if pericardial effusion BER or Pericarditis ST segment elevation in the two syndromes is similar PR segment in pericarditis is often depressed ST segment elevation in acute pericarditis tends to be widespread across the ECG T waves in pericarditis frequently is of normal amplitude and morphology, whereas the T wave in BER is frequently altered The ratio of the ST segment elevation to the height of the T wave (ST/T) is also a helpful guide; a ratio greater than 0.25 in lead V6 strongly suggests pericarditis BER or Pericarditis ST segment elevation in the two syndromes is similar PR segment in pericarditis is often depressed ST segment elevation in acute pericarditis tends to be widespread across the ECG T waves in pericarditis frequently is of normal amplitude and morphology, whereas the T wave in BER is frequently altered The ratio of the ST segment elevation to the height of the T wave (ST/T) is also a helpful guide; a ratio greater than 0.25 in lead V6 strongly suggests pericarditis BER or Pericarditis ST segment elevation in the two syndromes is similar PR segment in pericarditis is often depressed ST segment elevation in acute pericarditis tends to be widespread across the ECG T waves in pericarditis frequently is of normal amplitude and morphology, whereas the T wave in BER is frequently altered The ratio of the ST segment elevation to the height of the T wave (ST/T) is also a helpful guide; a ratio greater than 0.25 in lead V6 strongly suggests pericarditis BER or Pericarditis ST segment elevation in the two syndromes is similar PR segment in pericarditis is often depressed ST segment elevation in acute pericarditis tends to be widespread across the ECG T waves in pericarditis frequently is of normal amplitude and morphology, whereas the T wave in BER is frequently altered The ratio of the ST segment elevation to the height of the T wave (ST/T) is also a helpful guide; a ratio greater than 0.25 in lead V6 strongly suggests pericarditis Pericardial Effusion Electrical Alternans BER or AMI ST-T wave complex waveform Reciprocal changes Evolutionary changes BER or AMI ST-T wave complex waveform Reciprocal changes Evolutionary changes BER or AMI ST-T wave complex waveform Reciprocal changes Evolutionary changes LBBB LBBB- ECG Criteria QRS duration( 0.12 sec) Delayed onset of intrinsicoid deflection in leads I,V5, V6 Broad monophasic R waves in leads I, V5, V6 Secondary ST & T wave changes opposite in the direction to the major QRS deflection rS or QS complex in right precordial leads LAD may be present Prolonged LBBB- ECG Criteria QRS duration( 0.12 sec) Delayed onset of intrinsicoid deflection in leads I,V5, V6 Broad monophasic R waves in leads I, V5, V6 Secondary ST-T wave changes opposite in the direction to the major QRS deflection rS or QS complex in right precordial leads LAD may be present Prolonged LBBB- ECG Criteria QRS duration( 0.12 sec) Delayed onset of intrinsicoid deflection in leads I,V5, V6 Broad monophasic R waves in leads I, V5, V6 Secondary ST & T wave changes opposite in the direction to the major QRS deflection rS or QS complex in right precordial leads LAD may be present Prolonged QS QS rS LBBB With MI Fulfills criteria for LBBB Three criteria (Sgarbossa criteria) with independent value for diagnosing AMI: ST elevation 1 mm concordant to the major deflection of the QRS ST depression 1 mm in V1, V2, or V3 ST elevation 5 mm discordant with the major deflection of the QRS LBBB with Inferolateral MI ECG #2- 66 year old man with history of LBBB and 1 hour history of chest pressure LBBB and AMI LBBB and AMI Sgarbossa criteria 96% specific Pos LR = 22 Neg LR = 0.8 RBBB RBBB- ECG Criteria duration 0.12 sec Delayed onset of ID Increased amplitude of the R’ in V1-V2 Wide, slurred S wave in leads I,V5,V6 Secondary ST-T abnormality QRS RBBB Most patients with RBBB have CAD Many have no evidence of underlying heart disease In patients with AMI, RBBB is present in 3-7% of cases In uncomplicated RBBB, there usually is little ST-segment displacement AMI in The Presence of RBBB RBBB does not interfere with the recognition of infarcts. Even in presence of RBBB and either LAHB or LPHB, infarcts can be evaluated normally-EXCEPT True posterior MI RBBB, Inferoposterior MI RBBB+LAHB+ Anterolateral MI RBBB+LPHB+ Anteroseptal 30 year old diabetic found unresponsive Hyperkalemia ECG #5-72 year old male, PMH: CRF and a-fib presents with generalized weakness for 1 hour. 72 year old female found unresponsive ECG and ICH Most commonly SAH Altered autonomic tone as a mechanism Abnormalities include ST-segment elevation or depression Large, wide, upright , or inverted T waves Long QT interval Prominent U wave ICH 70 year old asymptomatic man with PMH of MI 75 year old man found unresponsive on a park bench, on New Years Eve, in Fargo… Many causes of STE Features that increase likelihood of AMI New STE New Q waves Any STE New LBBB