CC: Undifferentiated CP
But what if the chest pain (CP) isn’t myocardial infarction???
Thus far we have reviewed the STEMI and NSTEMI, each of which both have clear EKG findings and elevated markers of myocardial injury, usually troponin. There are also many other causes of “chest pain” with very obvious findings, like a stab wound to the chest. I have seen several times, herpes zoster on the chest wall triaged as “chest pain” in patients with communication impairments like dementia.
In textbooks, there are huge lists of potential causes of chest pain that attempt to be exhaustive.
Fairly exhaustive list, but somewhat impractical to clinical application with causes such as trauma and food impaction not likely to be missed with an actual history and exam.
I don’t find these huge lists helpful clinically. While CP may be part of the presenting complaint, many of the diagnoses above have other obvious features, such as trauma or excessive vomiting. Rib fractures and esophageal rupture usually have historical clues that do not obscure the diagnosis. Similarly, without trauma or rash several diagnoses below can be excluded.
In other words, you don’t need an exhaustive list such as this in every CP case, as many times there will be an obvious cause.
Instead, I would like to focus on…
UN-differentiated CP.
That is to say, there is no OBVIOUS cause of CP on the initial history, exam, EKG, and labs (all of which we will get to separately).
It is the "undifferentiated" patient that takes careful thought and documentation before discharging home. Anyone can admit a patient with undifferentiated CP for further work-up, but this is becoming increasingly rare with widespread use of accelerated diagnostic protocols (like the HEART pathway discussed later) and higher sensitivity troponins. The danger here is not in missing an MI, but in only looking for an MI and missing other important diagnoses.
“It is forgivable to miss a rare, devastating diagnosis. It is not forgivable to not think about, and document, it.”
This is why I so strongly believe in creating templates for your patient care. I use them as a reminder to consider potential dangerous causes of a patient’s presenting symptoms, and a shortcut in my documentation, having already laid out the rationale for testing or not testing. I also find it much faster to erase irrelevant diagnostic considerations, such as in the case of CP proven to be an MI by a positive troponin, than to dictate into my documentation all potential dangerous causes in a patient I am planning to discharge home.
Back to the matter at hand, however, and let's discuss ways to create a template or smart phrase to easily import into your notes of every undifferentiated CP patient to remind you of dangerous dx to consider and speed up your documentation to discharge. What conditions should be included in your MDM? Think about it for a second and try to list 10 diagnoses that cause "non-obvious" CP including all life-threatening causes.
(I'll wait)
What did you come up with? According to UpToDate here are the acute Life-threatening conditions that you should consider on EVERY CP patient.
Acute coronary syndrome
Acute aortic dissection
Pulmonary embolism
Tension pneumothorax
Pericardial tamponade
Mediastinitis
Thankfully, some of these have fairly obvious presenting features making them hard to miss. Yet, as we can see from litigation data, sometimes immediate life-threats are missed. I suggest considering these every CP visit.
From the list above, I don't consider the last 3 to be in the "undifferentiated" CP category because these patients are likely ill-appearing. It is debatable if they even need to be included in my MDM of patients that I discharge, but after reflection, I think they are worth mentioning as considered but not pursued because they are of minimal suspicion due to lack of risk factors or exam findings.
Of course, there are other possible causes of CP that are not immediate life threats and are listed here...
Cardiac causes:
An infection/inflammation process like pericarditis should be considered if symptoms support it.
Myocarditis would be accompanied by troponin elevation.
Endocarditis usually has other stigmata of septic emboli on examination.
Valvular disorder such as MVP could cause a brief CP sensation and aortic stenosis might cause chest discomfort (possibly through demand ischemia) with acute severe obstruction or aortic or mitral regurgitation which would likely cause pulmonary edema and poor perfusion.
Pulmonary cause:
Infections (pneumonia, tracheitis, and bronchitis) should have accompanying symptoms like fever, cough, etc.
Chest tightness is a common complaint with asthma exacerbations.
Pulmonary malignancy can cause chest pain particularly if there is pleural involvement. Chest heaviness or discomfort may be noted with pleural effusions
GI causes:
Gastroesophageal reflux and esophageal spasm, rupture (Boerhaave syndrome), or inflammation can all present as chest discomfort.
A sliding hiatal hernia may result in chest pain. Pain from pancreatitis can be referred to the chest.
MSK:
Rib contusions and fractures would have a history of trauma
Intercostal muscle strains probably would have an inciting event like coughing
Costochondritis should be associated with chest pain with palpation, but this should not be used to exclude other diagnoses, only to support a suspicion of MSK etiology.
Derm: herpes zoster, cellulitis, abscess, and dermatitis all have obvious skin findings (usually in a patient that can't communicate the nature of pain)
Depending on your experience and preference, you may or may not want to include reminders in your own CP template to look for signs and symptoms of the above diagnoses, but we’ll get to that…
