Acute Coronary Syndrome

Overview

Acute coronary syndrome describes a spectrum of acute myocardial ischemic syndromes caused by disruption of an atherosclerotic coronary plaque with subsequent thrombosis.

The clinical spectrum includes unstable angina and myocardial infarction.

Suspected acute coronary syndrome should be treated as a time-critical cardiovascular emergency.

Clinical Presentation

Patients commonly present with central chest discomfort, pressure, tightness, or heaviness that may radiate to the arm, shoulder, neck, jaw, or epigastrium.

Associated symptoms may include diaphoresis, nausea, dyspnea, weakness, or a sense of impending illness.

Atypical presentations are more common in some patient groups and should not be allowed to exclude the diagnosis prematurely.

Electrocardiography

ECG assessment is central to the early evaluation of suspected acute coronary syndrome.

ST-segment elevation in an appropriate clinical context may indicate acute coronary occlusion requiring urgent reperfusion-focused management.

A normal initial ECG does not completely exclude acute coronary syndrome.

Biomarkers

Cardiac troponins are important biomarkers of myocardial injury and are interpreted together with the patient's symptoms, ECG findings, and serial change over time.

Serial assessment is particularly useful when the initial biomarker result does not establish the diagnosis.

Management

Management depends on the clinical syndrome, ECG findings, haemodynamic stability, and the overall risk of adverse cardiovascular events.

Patients with acute coronary syndrome require rapid assessment, appropriate antithrombotic treatment, anti-ischemic management where appropriate, and timely reperfusion or invasive assessment when indicated.

In acute myocardial infarction, reducing the duration of coronary occlusion is a central determinant of myocardial salvage.

Clinical Pearls