Myocardial Infarction Differential Diagnoses

Updated: Jan 03, 2017
  • Author: A Maziar Zafari, MD, PhD; Chief Editor: Eric H Yang, MD  more...
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DDx

Diagnostic Considerations

Epigastric or chest symptoms from myocardial ischemia may incorrectly be attributed to a gastrointestinal (GI) source. Often, this occurs despite the presence of dyspnea or diaphoresis, symptoms that are difficult to attribute to the GI system. Additionally, patients with myocardial ischemia may report relief or improvement with GI remedies (eg, antacids).

The discomfort of myocardial ischemia may also erroneously be attributed to a musculoskeletal etiology. Tenderness of the chest wall is reported in as many as 5% of patients who are diagnosed with myocardial infarction (MI). If no injury or event is defined that could have led to a soft-tissue injury, the clinician should be reluctant to render a diagnosis of musculoskeletal chest pain.

Younger patients are overly represented in cases of missed MI. Most likely this is because of the inherent bias that MI is a disease of middle-aged and older individuals. Each patient with chest symptoms should be approached as an individual who could have the disease.

Unfortunately, in a series of missed MI, failure to recognize ischemic changes was frequent. The inferior leads, in particular, must be scrutinized carefully for any evidence of ST-segment elevation by using a straight edge across the T-P segments of the electrocardiographic (ECG) tracing. Another common error is to recognize ischemic changes and then discharge the patient without definitively proving that the changes were preexistent. Nonischemic causes of ST-segment elevation include left ventricular hypertrophy, pericarditis, ventricular-paced rhythms, hypothermia, hyperkalemia, and left ventricular aneurysm. Nonischemic causes may lead to overtreatment.

Differential Diagnoses