Symptomatic coronary artery disease can be divided into stable coronary artery disease and acute coronary syndromes. Asymptomatic coronary artery disease seldom present to the primary care physician and is often detected by a routine health check up or pre-operative evaluation. Stable coronary artery disease usually presents in the form of chronic stable angina. Acute coronary syndromes could be either unstable angina or acute myocardial infarction. Acute myocardial infarction can be further subdivided into ST elevation myocardial infarction (STEMI) and non ST elevation myocardial infarction (NSTEMI) depending on the presence or absence of ST segment elevation on the electrocardiogram (ECG). The term non ST segment elevation acute coronary syndromes (NSTEACs) comprise of NSTEMI and unstable angina. The difference between NSTEMI and unstable angina is the presence of evidence of myocardial necrosis in the former, in the form of an elevated biomarker, usually cardiac troponin.
Initial work up in acute coronary syndromes
Acute coronary syndrome usually presents with history of prolonged central chest pain, with or without specific radiation. Radiation of cardiac pain can be anywhere between the lower jaw and the umbilicus. A short history for asssessment of risk factors can be made at the time of initial evaluation. Vital signs are recorded, followed by a quick physical examination. ECG should be obtained the earliest, preferrably within 10 minutes. If there is a reasonable certainty regarding the diagnosis of acute coronary syndrome, initial loading doses of asprinin, clopidogrel and statin, often along pantoprazole are given. Acute coronary syndrome needs rapid hospitalization for further management.
High risk features in acute coronary syndrome
Certain high risk features may be evident in acute coronary syndrome at presentation. They include accelerating symptoms in the last 48 hours, rest pain lasting more than 20 minutes, features of pulmonary edema, new onset mitral regurgitation, tachycardia, bradycardia or hypotension, age above 75 years, angina associated with shift in the ST segment, bundle branch block, sustained ventricular tachycardia and elevated cardiac biomarkers (troponin or creatine kinase myocardial fraction).