UA and NSTEMI comprise part of the spectrum of ACS.
Rest angina, generally lasting longer than 20 minutes
●New onset angina that markedly limits physical activity
●Increasing angina that is more frequent, lasts longer, or occurs with less exertion than previous angina
ECG [12]:
●Any patient over 30 with chest pain
●Any patient over 50 with any of the following: dyspnea, altered mental status, upper extremity pain, syncope, or weakness
●Any patient over 80 with abdominal pain, nausea, or vomiting
close attention to older patients, diabetics, and women with symptoms consistent with ACS and using a low threshold for obtaining an ECG in such patients.
ECGs should be repeated at frequent intervals until the patient's chest pain resolves or a definitive diagnosis is made.at least every 20 to 30 minutes
ST elevation myocardial infarction (STEMI): New ST elevation at the J point in two anatomically contiguous leads using the following diagnostic thresholds: ≥0.1 mV (1 mm) in all leads other than V2-V3, where the following diagnostic thresholds apply: ≥0.2 mV (2 mm) in men ≥ 40 years; ≥0.25 mV (2.5 mm) in men <40 years, or ≥0.15 mV (1.5 mm) in women.
Non ST elevation myocardial infarction or unstable angina: New horizontal or down-sloping ST depression ≥0.05 mV (0.5 mm) in two anatomically contiguous leads and/or T inversion ≥0.1 mV (1 mm) in two anatomically contiguous leads with prominent R wave or R/S ratio >1.
●Anterior wall ischemia – Two or more of the precordial leads (V1-V6) (waveform 2A-B)
●Anteroseptal ischemia – Leads V1 to V3 (waveform 3)
●Apical or lateral ischemia – Leads aVL and I, and leads V4 to V6 (waveform 4)
●Inferior wall ischemia – Leads II, III, and aVF (waveform 1)
●Right ventricular ischemia – Right-sided precordial leads (waveform 1)
●Posterior wall ischemia – Septal precordial leads (V1-V2) (waveform 5) and posterior precordial leads
LBBB or pacemaker — Both left bundle branch block (LBBB), which is present in approximately 7 percent of patients with an acute MI, and pacing can interfere with the electrocardiographic diagnosis of coronary ischemia. Another problem is that approximately one-half of patients with LBBB and an acute MI do not have chest pain as a symptom of their ischemia. clinical history and cardiac enzymes are of primary importance in diagnosing an ACS in this setting.
NSTEMI is distinguished from UA by the presence of elevated serum biomarkers
Thrombolytic therapy should NOT be administered t
High-risk patient — The patient has a high-risk ACS if ST segment depression (≥0.05 mV [0.5 mm]) is present in two or more contiguous leads, elevated serum biomarkers, and/or the TIMI risk score is ≥5.
> reperfusion using PCI
Low and moderate risk patient — The management, including methods for risk assessment
MISSED DIAGNOSIS —
●Women less than 55 years of age
●Nonwhite
●Shortness of breath as the major presenting symptom
●Normal or nondiagnostic ECG
Rest imaging tests, including radionuclide myocardial perfusion imaging (rMPI) and echocardiography,