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Myocardial Infarction: Difference between revisions
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===Risk assessment of Cardiovascular disease=== | ===Risk assessment of Cardiovascular disease=== | ||
Narrowing of the coronary artery, leading to a myocardial infarction, usually develops over several years. An increased risk of cardiovascular disease, which may lead to a myocardial infarction or cerebrovascular accident, can be estimated using [http://www.escardio.org/ | Narrowing of the coronary artery, leading to a myocardial infarction, usually develops over several years. An increased risk of cardiovascular disease, which may lead to a myocardial infarction or cerebrovascular accident, can be estimated using [http://www.escardio.org/communities/EACPR/toolbox/health-professionals/Pages/SCORE-Risk-Charts.aspx SCORE system] which is developed by the European Society of cardiology (ESC). | ||
As shown in the figure, the most important risk factors for myocardial infarction are: | As shown in the figure, the most important risk factors for myocardial infarction are: | ||
*Male sex | *Male sex | ||
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| V1-V4, disappearance of septum Q in leads V5,V6 | | V1-V4, disappearance of septum Q in leads V5,V6 | ||
| none | | none | ||
| LAD | | LAD-septal branches | ||
|- | |- | ||
| [[Lateral MI]] | | [[Lateral MI]] | ||
| I, aVL, V5, V6 | | I, aVL, V5, V6 | ||
| II,III, aVF | | II,III, aVF | ||
| | | LCX or MO | ||
|- | |- | ||
| [[Inferior MI]] | | [[Inferior MI]] | ||
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[[Image:AMI_evolutie.png|thumb| The evolution of an infarct on the ECG. ST elevation, Q wave formation, T wave inversion, normalisation with a persistent Q wave]] | [[Image:AMI_evolutie.png|thumb| The evolution of an infarct on the ECG. ST elevation, Q wave formation, T wave inversion, normalisation with a persistent Q wave]] | ||
[[Image:PathoQ.png|thumb| A [[Pathologic_Q_Waves|pathological Q wave]]]] | [[Image:PathoQ.png|thumb| A [[Pathologic_Q_Waves|pathological Q wave]]]] | ||
[[File:DVA1995.jpg|thumb|Wellens syndrome: symmetrical negative T wave in pre-cordial leads without R loss of R waves can regularly be observed in early anterior ischemia. Many patients with Wellens syndrome / sign turn out to have a critical proximal LAD stenosis<cite>WellensSign</cite>.]] | |||
[[Image:anteriorMInegativeT.png|thumb| Typical negative T waves post anterior myocardial infarction. This patient also shows QTc prolongation. Whether this has an effect on prognosis is debated.<cite>Novotny</cite><cite>Jensen</cite><cite>Chevalier</cite>]] | [[Image:anteriorMInegativeT.png|thumb| Typical negative T waves post anterior myocardial infarction. This patient also shows QTc prolongation. Whether this has an effect on prognosis is debated.<cite>Novotny</cite><cite>Jensen</cite><cite>Chevalier</cite>]] | ||
The cardiomyocytes in the ''subendocardial'' layers are especcially vulnerable for a decreased perfusion. Subendocardial ischemia manifests as ST depression and is usually reversible. In a myocardial infarction ''transmural ischemia'' develops. | The cardiomyocytes in the ''subendocardial'' layers are especcially vulnerable for a decreased perfusion. Subendocardial ischemia manifests as ST depression and is usually reversible. In a myocardial infarction ''transmural ischemia'' develops. | ||
In the first hours and days after the onset of a myocardial infarction, several changes can be observed on the ECG. First, '''large peaked T waves''' (or ''hyperacute'' T waves), then '''ST elevation''', then '''negative T waves''' and finally '''[[Pathologic_Q_Waves|pathologic Q waves]]''' develop. | In the first hours and days after the onset of a myocardial infarction, several changes can be observed on the ECG. First, '''large peaked T waves''' (or ''hyperacute'' T waves), then '''ST elevation''', then '''negative T waves''' and finally '''[[Pathologic_Q_Waves|pathologic Q waves]]''' develop. | ||
'''Wellens syndrome''' or sign (see image) can be an early ECG warning sign of critical anterior ischemia before the development of overt mocardial infarction. | |||
{| class="wikitable" | {| class="wikitable" | ||
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#Thygesen pmid=17951284 | #Thygesen pmid=17951284 | ||
#Wong pmid=15992631 | #Wong pmid=15992631 | ||
#WellensSign pmid=6121481 | |||
</biblio> | </biblio> | ||
}} | }} | ||