Hi Mona,

Generally speaking, the typical manifestations of myocardial infarction usually come with chest pain, whereas, an a typical presentation of myocardial infarction includes the absence of chest pain and the presence of non-chest pain, particularly localized in the neck, back, jaw, or head, followed by non-pain symptoms such as weakness, sweating, nausea, dyspnoea, or cough. Women seem to be another subgroup with a greater likelihood of atypical presentation pattern (Am Heart J 2002;144:1012-1017) which agrees with a greater presence of unrecognized infractions among them compared with men (Eur Heart J 2006;27:729-736). A typical myocardial infractions are also increased in incidence in patients aged 55 and older. The underlying mechanisms is uncleared and that may be due, at least in part, to the gender difference in neurocontrol of circulation and reflex function. Hope this would help with your question.

Dear Mona. I think that you question not have a brief and total answer. Myocardial infarction during my clinical residence was a very different patology. The progress in the knowledge about coronary heart disease allowed the diagnosis of myocardial infarction with many different symptoms, and including the asymptomatic infarction. So, I think that is necessary the cardiologist or general doctor remember the possibility of myocardial infarction as the most frequent cause of mortality, and include it in the routine investigation in the emergency service and in his office.

Hi,

I don't know of any hard and fast definitions of 'atypical' either. Your textbook definition of an MI would of course be central crushing chest pain radiating to the arms/neck, with breathlessness, pallor and an impending sense of doom (love that terminology). Sometimes there is dizziness/loss of consciousness if circulation to the brain is compromised. But of course we know that MIs can also be silent with no pain and so sometimes those other symptoms can be very helpful. The overall presentation of an MI like this might be termed atypical as its relatively uncommon and could be mistaken for another condition serious or not. Certainly breathlessness itself is a typical symptom of MI sufferers, its just atypical on its own without chest pain.

After a quick search I found this article helpful about 'atypical chest pain', which is something cardiology clinicians have to deal with fairly regularly:

http://drsvenkatesan.wordpress.com/2008/09/14/what-do-we-mean-by-atypical-chest-pain/

In these cases we have to decide whether we are convinced by the pain as atypical cardiac pain ie. we think the patient indeed has a cardiac problem but the symptoms aren't textbook. Usually if the pain is 'atypical' in every way and the patient has no other risk factors eg. history of coronary arterial disease, smoking, family history, diabetes, hypertension, hypercholesterolaemia, advanced age, abnormal ECG etc. then we can reassure the patient. Often we're not sure and we end up doing further tests eg. stress echo/SPECT, coronary angio for a more definitive answer.

Certainly atypical presentations of MIs can catch out the best. Hope this helps.

The answer is more complex than has been discussed. There is usually chest pain, but the nature of the chest pain is variable, and elusive. My grandfather was perfectly healthy walking every day, but when he went to Case-Westyrn Reserve ER, he was sent home because maybe he had tightness in the chest. My aunt knew that that was really atypical and he was brought back. Lee Goldman somewhat resolved the problem in his algorithm - STABBING excludes MI (not always). Crushing, tightness, difficulty breathing, are in, and radiation to the left arm is additionally helpful. It may present as a "gallbladder attack" because of the innervation by the vagus nerve.

The second feature that is important, but not always helpful is the EKG. ST elevation is diagnostic. Q-wave is pathognomonic if not preiously known. ST depression is a red flag, and T-wave inversion can't be discarded. Normal sinus rhythm might exclude MI, and perhaps atypical EKG abnormalities that are not the above.

The third part of the discussion is the use mof cardiac biomarkers. The original test was SGOT (AST) that was introduced by Arthur Karmen, a medical student at Albert Einstein. There may also be a neutrophil elevation because of the inflammatory response. Then came LAH and CK, followed by LD isonzyme 1 and CK isoenzyme MB. They have a characteristic rise to peak and decline. The introduction of troponins T and then I, changed the landscape. Then the troponins were made ultrasensitve, so that minor elevations were identified from ischemia, but then we have type 1 and type 2 infarcts. The type 1 infarct is associated with plaque rupture. It is a slam dunk. The type 2 is below level of the original diagnostic cutoff based on ROC curve analysis. A major confounder can be chroni kidney disease.

It is my personal opinion that a careful analysis of the warning signs that change, even if only slightly, the previous state of well being of a person can help to predict the possible occurrence of an acute myocardial infarction even before the onset of the classical chest pain syndromes and, therefore, allowing intervention to reduce its intensity. By so doing, the gap existing between typical and atypical forms of myocardial infarction could be reduced. It is , however, worthy to be emphasized that atypical forms of myocardial infarction without chest pain, sometimes accompanied with symptoms similar to those of the acute heart failure, may occur in elderly patients and those with diabetes for a reduced perception of pain in this group of individuals due to altered autonomic nervous system responses, and , increasingly documented observations, in male subjects chronic heavy smokers.

Hi

I think doctors should consider the possibility ACS for any symptomatic patient with CV risk factor no matter typical or atypical manifestations. EKG is a simple and effective tool especially two measurements with 2h interval.

Hi Mona

I think ,we should correct the question to "typical and atypical Angina instead of MI".

In cardiology view IM AMI patients we have a severe retrosternal pain with ECG changes and biomarker elevation that documented the diagnosis .Only presence of acute chest pain didn't approve AMI but we have atypical presentations of AMI without symptom(silent MI) that detect incidentally in ECG and atypical chest pain like presence of weakness ,sweating , dyspnea, dizziness associated with ECG and biomarker changes.

Any pain from mandible to epigastria may be due to angina as a marker of MI ,but typical angina is a tightness , burning ,pressing and pain in retrosternal position that aggravated with walking and relieved with NTG (except in AMI) and atypical angina may be asymptom other than pain such as dyspnea dizziness ,.. or a pain in another location for example in both arms or both wrists or mandible, epigastria and...

There are certain gender differences in clinical manifestation of ACS. Females often present with atypical chest or abdominal pain, dyspnea, nausea or unmotivated fatigue as equivalents of ACS. Some authors define so called 'female pattern' of CHD symptoms. As women develop CHD later in time continuum than men, they usually have associated diseases that frequently mask signs of myocardial ischemia, besides women often present with painless (silent) myocardial ischemia.

hello everybody

I would like to add that atypical chest has many features, including plueritic pain that is often variable and increases over time, and this might be a psychosomatic or an ischemia related pain; both are possible. Although plueritic pain might sometime include pulmonary conditions to the list of possibilities, but the vague history of the patient accompanied by previous undefined complaints of chest discomfort and feeling sick during the previous periods would, in a manner, provide you with a sense of direction. I do believe that positive personal and family history would provide a strong evidence of the presence of ACS as a highly possible condition accompanied by atypical chest pain.

I had seen symptoms like abdominal discomfort and other hard-to-relate symptoms behind MI, specifically those involving the inferior wall. Not to forget that we express our feeling of pain based on many variables, including our culture, education and the impact of the person who is performing the assessment. It is more objective to provide patients with a paper and a pen and let them write what and how they felt when they were experiencing pain.