Helping our ER Doctors

What can our Emergency Room Doctors do to be able to quickly diagnose an aortic dissection?

The diagnosis of aortic dissection is a particularly difficult one, since it is still relatively rare, yet the consequences of a delay in diagnosis can be disastrous. The frequency of heart attack is still much higher than the frequency of aortic dissection, so thinking of a heart attack in someone with chest pain is still the first instinct. I think the most important thing for the treating physician and what I teach all my residents is to always consider the 3 diagnoses that can kill the patient suddenly which present with chest pain, myocardial infarction, aortic dissection and pulmonary embolus. The physician should, consciously, go over why he/she would exclude each of those diagnoses.

The things that point toward an aortic dissection would be:

1. Very abrupt onset of pain

2. Loss of pulses/perfusion in any extremity

3. Family history of dissection/Marfan syndrome

4. Lack of evidence of the other diagnoses on initial examination in a patient who appears ill.

Unfortunately, these features are far from universally present, which leads to frequent delays in diagnosis of aortic dissection. A CT scan or a transesophageal echocardiogram would certainly have made the diagnosis in John Ritter's case, however doing a scan in every patient with chest pain would not be appropriate for reasons of procedural morbidity, patient discomfort and cost.

One step I would propose would be to increase the use of transthoracic echocardiography in the emergency room. Although, the transthoracic echo is far from definitive in ruling in or ruling out an aortic dissection, it probably does a better job than any of the other available inexpensive noninvasive tests. A transtoracic echocardiogram can also help to confirm one of the others of the 3 diagnosis allowing the physician to be more effective in using CT and TEE in evaluating the remaining patients without firm diagnoses.

With this there will still be missed or delayed diagnoses of aortic dissection. Perhaps a day will come when we can do a 3 minute MRI scan from head to toe. That may be what will be necessary to reach 100% accuracy in the diagnosis of aortic dissection. In the meantime keeping aortic dissection in the minds of emergency physicians is probably the most important step. The important message is that not all chest pain is either a heart attack or it is nothing, the two acutely life threatening diagnoses should always be considered,

David