TOPICS IN EMERGENCY MEDICINE SEMI-FINAL

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1 RISK ASSESSMENT IN PATIENTS WITH CHEST PAIN Nora Goldschlager, M.D. FACP, FACC, FAHA, FHRS Cardiology - San Francisco General Hospital UCSF Disclosures: None 1 CHEST PAIN NOT DUE TO MYOCARDIAL ISCHEMIA Pericarditis Aortic dissection Esophageal spasm/rupture/reflux Peptic ulcer disease Cervical spine disease Pulmonary embolism Musculoskeletal Mediastinitis/pneumomediastinum 2 MYOCARDIAL ISCHEMIA NOT DUE TO CORONARY ARTERY DISEASE Aortic valve disease (aortic stenosis) Hypertrophic cardiomyopathy (obstructive and nonobstructive) Dilated cardiomyopathy Tachycardia Hypertension Coronary artery embolism Syndrome X (chest pain, and positive treadmill, normal coronary arteries on angiography) Coronary artery dissection (e.g., Ao dissection, cocaine) Coronary arteritis Tako-tsubo cardiomyopathy 3 ASSESSMENT OF RISK FOR CORONARY ARTERY DISEASE Is CAD known to be present (past angina, MI)? If CAD is not known to be present, what is the risk profile? (lipids, blood pressure, diabetes, family history, smoking) What are the symptoms and what brings them on? Are there physical findings of acute ischemia? of past MI? Are there ECG abnormalities, and are they reversible? What is the response to sublingual nitroglycerin? 4 5 ISCHEMIC CHEST PAIN SYNDROMES Stable effort angina Crescendo angina Acute coronary syndromes - Unstable angina - Acute MI: ST elevation, non ST elevation 6 1

2 WOMEN: PROBLEMS IN MANAGEMENT OF CHD Significant gender gap in MI mortality Women, particularly younger women, have a more adverse CHD prognosis than men Adjustment for disease severity, comorbidity and treatment does not fully account for the gap Women with normal or minimal CAD have an adverse prognosis that is comparable to diabetics PATHOPHYSIOLOGY OF MYOCARDIAL ISCHEMIA IN WOMEN Outcomes Following Normal/Minimal CAD at Cath 29% perfusion abnormality 65% persistent symptoms at 5 years despite conventional med Rx 10% required rehospitalization for symptoms Outcomes Following Significant CAD at Cath Less obstructive stenoses More myocardial ischemia More unstable angina and fewer transmural infarcts More adverse prognosis compared to men WHY DO WOMEN HAVE A MORE ADVERSE CHD PROGNOSIS? Not due to atypical presentation Not due to age Not due to comorbitidy Not due to gender gap in medical therapy Not due to more advanced angiographic CAD Differences in physiological vascular function (endothelial and microvascular reactivity) are likely (?partial) explanations WISE STUDY: WOMEN S ISCHEMIA SYNDROME EVALUATION 10 SHORT-TERM RISK OF DEATH OR NONFATAL MI IN PATIENTS WITH UNSTABLE ANGINA - 1 HIGH INTERMEDIATE LOW Hx Acclerating Prior MI, peripheral or tempo of cerebrovascular disease, ischemic sx or CABG/PCI, prior ASA use in 48 h Pain Prolonged Prolonged (> 20 min) rest New onset or progressive ongoing (> angina, resolved, with Class III or IV angina in 20 min) rest moderate or high 2 wks, with moderate or pain likelihood of CAD high likelihood of CAD Rest angina (<20 min) or relieved with rest or SL NTG Clinical Pulmonary Age 70 yrs edema, new or worsening MR, S 3 or new/ worsening rales, hypotension, bradycardia, tachycardia Age > 75 yrs 11 SHORT-TERM RISK OF DEATH OR NONFATAL MI IN PATIENTS WITH UNSTABLE ANGINA - 2 HIGH INTERMEDIATE LOW ECG Angina at rest T-wave inversion Normal or unchanged with transient during chest discomfort ST-segment changes Pathological Q- > 0.05 mv waves BBB, new or presumed new Sustained VT Cardiac Elevated Slightly elevated Normal markers 12 2

3 TIMI RISK SCORE for UA/NSTEMI Historical POINTS Age CAD risk factors 1 14-DAY RISK OF CARDIAC EVENTS (%) (FHx, HTN, chol, DM, smoker) Known CAD (stenosis 50%) 1 RISK DEATH/MI ASA use in past 7 days 1 SCORE DEATH/MI URGENT REVASC Presentation 0/1 3 5 Recent ( 24 h) severe angina cardiac markers mm ST RISK SCORE: Total Points (0-7) TIMI RISK SCORE for STEMI Historical POINTS Age DM, HTN or angina 1 RISK SCORE 30-DAY MORTALITY (%) Exam SBP < 100 mmhg HR > 100 bpm Killip II-IV Weight < 67 kg Presentation Anterior STE or LBBB Time to Rx > 4 hrs 1 >8 36 RISK SCORE EVALUATION AND MANAGEMENT OF PATIENTS WITH SX SUGGESTIVE OF ACS Possible ACS Definite ACS No ST ST Nondiagnostic ECG ST and/or T wave changes Normal initial cardiac Ongoing pain Evaluate for markers + cardiac markers reperfusion Observe FU at 4-8 hours ECG, cardiac markers No recurrent pain Recurrent ischemic pain - FU studies or + FU studies: Dx confirmed Stress study to provoke ischemia Evaluate LV function if ischemia - : Potential diagnoses: nonischemic +: Dx confirmed Admit CP, low-risk ACS Rx for ACS Total points (0-14) OP FU ACC/AHA Guidelines BIOCHEMICAL CARDIAC MARKERS FOR THE EVALUATION AND MANAGEMENT OF PATIENTS SUSPECTED OF HAVING AN ACS - 1 Marker: Troponin Advantages: Powerful tool for risk stratification Greater sensitivity and specificity than CK-MB Detection of MI up to 2 weeks after onset Disadvantages: Low sensitivity in very early phase of MI (< 6 h after symptom onset) Limited ability to detect late minor reinfarction Recommendation: Useful as a single test to diagnose NSTEMI 16 BIOCHEMICAL CARDIAC MARKERS FOR THE EVALUATION AND MANAGEMENT OF PATIENTS SUSPECTED OF HAVING AN ACS - 2 Marker: CK-MB Advantages: Rapid, cost-efficient, accurate assays Ability to detect early reinfarction Disadvantages: specificity in setting of skeletal muscle disease or injury Low sensitivity during very MI (< 6 h after sx onset or later (> 36 h) and for minor myocardial damage detectable by troponins Recommendation: Prior standard still acceptable in most clinical circumstances. 17 MI patients (n) STENOSIS SEVERITY PRIOR TO MI Stenosis prior to MI > 70% 50-70% < 50% 0 Ambrose Little Nobuyoshi Giroud All

4 PATHOPHYSIOLOGY OF ACUTE CORONARY SYNDROMES 2006 Plaque Disruption / Erosion Atherosclerosis: Traditional vs. Contemporary Model Coronary remodeling concealing extensive disease Thrombus formation & Embolization Unstable Angina Non-ST Elevation MI ST Elevation MI Traditional Contemporary Nissen, S. E. J Am Coll Cardiol 2003;41:103S-112S Copyright 2003 American College of Cardiology Foundation. Restrictions may apply. 21 CLINICAL PRESENTATION OF MYOCARDIAL ISCHEMIA Chest pain/pressure/burning/ fullness/squeezing Epigastric discomfort/fullness/burning Jaw/throat/tooth pain Shoulder/back discomfort Breathlessness Fatigue Acute or worsening peripheral vascular insufficiency Dizziness, syncope THE OLDER THE PATIENT THE LESS PHYSICAL EXAMINATION DURING ACUTE MYOCARDIAL ISCHEMIA / INFARCTION S 3 gallop Paradoxically split S 2 Soft S 1 (PR interval, dp/dt) Mitral regurgitation murmur (transient) Hypotension Alterations in pulse volume Pallor, diaphoresis, anxiety, tachycardia (nonspecific) CLASSIC THE PRESENTATION ECG FINDINGS IN ACS ST-T abnormalities - ST elevation - ST depression - Pseudonormalization Intraventricular conduction delay Transient Q waves 24 4

5 PITFALLS IN THE ECG DIAGNOSIS OF ACUTE MI DURING PAIN AFTER PAIN 25 Pseudonormalization of T-wave inversion during angina 26 Nonspecific ST/T-wave abnormalities Age of Q-waves (may not be known) Early repolarization pattern Paced ventricular rhythm Left bundle branch block Right bundle branch block: secondary ST-T abnormalities in V 1-3 can mimic anterior-wall MI; tall R-waves in V 1-2 can mimic posterior-wall MI Nonspecific intraventricular conduction delay with repolarization abnormalities Atrial flutter with flutter waves pseudo ST or Double standardization 27 PERICARDITIS vs EARLY REPOLARIZATION DIAGNOSIS OF ACUTE MI IN LBBB 1 mm ST segment change in same direction as terminal QRS More than 5 mm ST elevation in direction opposite to QRS Sgarbossa criteria (NEJM 1996;334:481) - ST-elevation > 1 mm in lead with concordant QRS complex 5 points - ST-depression > 1 mm in leads V1, V2 or V3 3 points - ST-elevation > 5 mm in lead with discordant QRS complex 2 points

6 Same patient, baseline ECG obtained 6 months earlier PITFALLS IN THE ECG DIAGNOSIS OF ACUTE MI: MI MIMICS Hyperkalemia Myocarditis Post-defibrillation Pericarditis with PR depression (scooped ST segments) Early repolarization LVH Wide QRS complex tachycardias Left anterior fascicle block (poor R wave progression; q V 2-3, I, avl) Left posterior fascicle block (q II, III, avf) WPW patterns Pneumothorax with mediastinal shift WPW MIMICKING INFEROPOSTERIOR WALL MI 36 6

7 WPW MIMICKING INFERIOR WALL MI HYPERKALEMIA vs ANTERIOR WALL MI vs BRUGADA SYNDROME EFFECT ON OUTCOMES OF MISSING HIGH RISK (ACUTE INJURY MI) ECG IN THE ED Missed Dx 12% (5 15%) Effect on Rx (odds ratio) No ASA 2.13 No β blocker 1.85 Mortality 7.9% ( vs 4.9% in ECG dx made correctly) Correlates of missed Dx Advanced age HF history No chest pain ECG patterns in missed Dx STE 8% ST DEP 18% T inversion 14% Masoudi et al Circulation 2006; 114:1565. N = 1684, 2 yr retrospective multicenter study ESOPHAGEAL PAIN More likely to: - Continue for hours, rather than stuttering - Be retrosternal, without lateral radiation - Be nonexertional - Interrupt sleep - Be meal-related - Be relieved with antacids - Be associated with heartburn, dysphagia, regurgitation 42 7

8 SOME REASONS TO PERFORM ECHO IN PATIENTS WITH CHEST PAIN AND SUSPECTED CAD Suggestive of CAD - Segmental wall motion abnormalities (prior MI/ischemia) - Reduced ejection fraction with WMA (ischemic cardiomyopathy) Not necessarily suggestive of CAD - LVH (hypertension, hypertrophic cardiomyopathy) - Aortic valve stenosis - Intimal flap of aortic dissection - Reduced ejection fraction - no segmental WMA -RVH 43 8