Acute Coronary Syndrome
Pathophysiology
Acute coronary syndrome (ACS) is almost always due to rupture of an atherosclerotic plaque with subsequent partial or complete thrombosis of a coronary artery.1 Acute coronary syndrome can also result from artery dissection, catecholamine surge (Takotsubo cardiomyopathy), aortic valve disease, sympathomimetic agents (cocaine).
Classification of presentation
Angina – exercise or stress related chest pain or pressure that resolves with rest or by removing the offending stimulus, or with nitrate therapy
Unstable angina – chest pain or pressure that begins at rest or during only minimal exertion and does not resolve with rest or with the use of nitrate therapy
Acute myocardial infarction – significant interruption of one or more coronary arteries resulting in cardiac cell damage / necrosis. Some patients may develop ECG changes (STEMI) while others may not (non-STEMI)
Clinical Presentation
Classic (patients often present with several/all of the following)
- Male
- > 60 years of age
- Left sided chest pain or pressure
- Radiation to left arm, neck, jaw
- Nausea / vomiting
- Diaphoresis
Atypical (patients often present with one of the following; vague presentation)
- Female
- < 55 years of age
- No chest pain or pressure
- Dyspnea
- Unexplained diaphoresis
- Nausea / vomiting
- Syncope / near syncope
Assessment
History – symptoms that favor ACS
- Pressure
- Burning
- Indigestion
- Similar / worse than previous AMI
- Radiation
- Exertional
- Longer duration
History – symptoms that favor something other than ACS
- Stabbing
- Sharp
- Pleuritic
- Positional
- Brief episode of pain
Physical
Diagnostic tests
ECG – record a 3-lead and 12-lead ECG tracing.
Management
Goals of prehospital therapy
Therapy
Endpoint of therapy
Transport destination
Transport destination decision tool
Pearls and Pitfalls
- Don’t rule out ACS solely based on the history. Patients experiencing ACS can present with right-sided, sharp, stabbing chest pain.
- Coronary artery disease risk factors are not predictive of ACS
- Severity of pain is not predictive of ACS versus something non-cardiac
- Beware of your personal race, gender, and socioeconomic status bias! Cardiovascular disease does not discriminate!
- A normal, non-diagnostic, or non-STEMI ECG does not rule out ACS
Reference
- http://emedicine.medscape.com/article/1910735-overview