1 DIAGNOSTICS OF Acute Coronary Syndromes At the end of this self study the participant will: Verbalize meanings of specific ECG changes: –ST Elevation –ST Depression Describe common tests used for patients with suspected Acute Coronary Syndromes

2 Abbreviations: ACS = Acute Coronary Syndrome STEMI = ST Elevation Myocardial Infarction AMI = Acute Myocardial Infarction PCI = Percutaneous Coronary Intervention (e.g., angioplasty, stents)

3 Time is Still Muscle! 4 D’s of Timely Reperfusion Door to Data (ECG) Goal < 10 min. Door to Decision Goal < 20 min. Door to Drug Goal < 30 min. Door to Dilatation Goal < 90 min. Door can be time of patient arrival, or time the patient tells nursing staff of possible ACS signs and symptoms

4 Door to Data: 10 minutes INITIAL DIAGNOSIS –12-LEAD ECG ST Elevation –ST elevation MI (STEMI) – All High Risk No ST elevation –Acute Coronary Syndrome OR Non ST elevation MI (Non STEMI) »High, Intermediate or Low Risk

5 Lead Placement to obtain a 12- lead. V lead (chest lead) placement must be exact.

6 Normal 12 Lead EKG Configurations In order to more easily recognize abnormalities in the 12 lead ECG one must first be able to recognize the normal 12 lead ECG Look for: Flat baseline Little to no artifact (waveforms are clear)

7 12-lead changes seen in ACS 1.4 MM Non-ST elevation ACS 0.6 MM ST-elevation MI ~ 2.0 MM patients admitted to CCU or telemetry annually ST ElevationST depressionT wave inversion

8 Ischemia

9 Injury

10 ECG Progression in AMI From Garcia, et.al. (2001). 12 Lead ECG. The Art of interpretation, pg Used by permission. ST-segment elevation may occur within the first few hours of infarction. ST-segment elevation is indicative of injury that is leading to infarction. When ST-segment elevation is seen, time is limited and the healthcare provider must act quickly to initiate a reperfusion strategy in order to salvage the most myocardium.

11 Non-diagnostic ECGs According to the National Registry of Myocardial Infarction, only 39% of Acute MI patients have STEMI on admit Subsequent STEMI occurs within 12 hrs of symptoms Acute MI patients who present & maintain normal or nonspecific ECGs have lower mortality rates; Increased mortality risk associated with development of STEMI Fesmire, FM, et al. Ann Emerg Med. 1998: 31: Littrell, KA, et al. JACC. 2001: 37 Suppl A p French, WJ, et al. NRMI 4 Special Report, June 2001 Welch, RD, et al. JAMA, 2001: 286:

12 Door to decision: 20 minutes Based on ECG and patient presentation Does not require lab data nor advanced assessments such as angiography (cardiac catheterization) If decision is AMI, treatment planned –Door to Drug 30 minutes –Door to Dilatation (PCI) 90 minutes If decision is not AMI, further evaluation is required

13 ACS DIAGNOSIS CARDIAC ENZYMES –Negative Unstable Angina Non-cardiac? –Positive MI

14 Serum Enzyme Changes OnsetPeak TimeDuration CPK-MB4-6 hours12-24 hours2-3 days Troponin-I4-6 hours12-24 hoursUp to 10 days Myoglobin1-2 hours4-6 hours24 hours

15 Diagnostic Tests Echocardiogram evaluates: Wall motion and valve function Ejection fraction (EF) –% of blood pumped out of ventricle with each beat –normal = 60-70%; –failure = < 40% –The greater the damage, the greater the muscle loss, the lower the EF

16 Diagnostic Tests Stress Testing: only performed if enzymes are negative. ECG Perfusion Studies (indicate capillary perfusion = better predictor) –Exercise Thallium –Dobutamine Stress Echo –Adenosine Thallium

17 Cardiac Catheterization (Angiography) Access: radial, brachial or femoral arteries If we can upload from YouTube, there’s a terrific video (no audio) of a cath v=yzxSrLa1d0g

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19 Possible Post-Cath Complications Hypotension Active Bleeding Limb Ischemia Recurrent Ischemia/MI Arrhythmias: Ventricular and Bradycardia Contrast Reaction Contrast Nephropathy Congestive Heart Failure Neuro Deficits

20 Post Cath Care Sheaths are used with all PCI’s –Assess for bleeding at site, and under the site; outline ecchymotic areas –Note any perfusion changes around site –Palpate abdomen for firmness or distention –Be alert to changes in oxygenation assessment and hemodynamic status If bleeding is seen at site, place immediate manual pressure Monitor peripheral pulses

21 Next: ACS Treatments