Chest pain history and the odds of ischaemia

We look at a lot of ECG's and we do a lot of troponins, however the most important thing we are going to do in the patient who presents with chest pain is take a good history. Regardless of a normal troponin or a normal ecg, if the patient has a very good history for acute coronary syndrome, we have to admit that patient, or at least watch them and do serial testing. The low risk group that we clear with rapid rule-out criteria, are just that, low risk on history.

Here is an example of a patient who presents to the emergency department with chest pain. Please rank the following in terms of likelihood for predicting a myocardia infarction, or at least ischaemia.

• Left arm pain
  
• Right arm pain
  
• Indigestion pain

ANSWER

1. Right arm pain (LR 4.7)
2. Indigestion pain (LR 2.8)
3. Left arm pain (LR 2.3)

CASE
A patient presents to the emergency department with chest pain and you put a pre-test probability of x% on that chest pain being ischaemic. How does it change with the following? DOES IT INCREASE OR DECREASE THE CHANCE THAT THIS IS ISCHAEMIC PAIN?

PAIN RADIATES TO RIGHT ARM

ANSWER

INCREASES
PPV 34.6%
​LR 2.31

THE PATIENT HAS VOMITED

ANSWER

INCREASES
PPV 41.4%
​LR 3.09

THE PATIENT IS DIAPHORETIC

ANSWER

INCREASES
PPV 59.3%
​LR 6.39

The table below looks at the PPV and Likelihood ratios of predictors for AMI

Reference
Body R et al. ​The value of symptoms and signs in the emergent diagnosis of acute
coronary syndromes. Resuscitation 81 (2010) 281-286.

Members go to the Chest Pain and Troponin Section of the Course and watch the videos