St Segment Elevated Myocardiac Infarction

of 17
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
for medical student reference
  ST SEGMENT ELEVATED MYOCARDIAC INFARCTION (STEMI) Objectives These guidelines are intended to provide awareness and education in Early recognition of STEMI Evidence-based practice for the management of STEMI Secondary prevention following STEMI with the intention of reducing the morbidity and mortality associated with MANAGEMENT OF ACUTE ST SEGMENT ELEVATIORDIAL INFARCTION (STEMI) Clinical Questions ã Diagnosis   ã Treatment strategy   ã Risk reduction   ã Special group  - Elderly - Diabetics - Women ELEVATION TERMINOLOGY Acute coronary syndrome (ACS) is a clinical syndrome of IHD ranging from unstable angina, NSTEMI to STEMI depending upon the degree and acuteness of coronary occlusion. STEMI: Myocardial infarction due to acute TOTAL occlusion of the coronary artery NSTEMI: Myocardial infarction due to acute SUB-TOTAL occlusion of the coronary artery Pathogenesis of STEMI STEMI is necrosis of heart muscle due to inadequate blood supply following an acute total coronary occlusion. This occlusion is usually due to atherosclerotic plaque rupture, fissuring or ulceration with superimposed thrombosis and coronary vasospasm. Rarely, it may result from nonatherosclerotic arterial disease such as coronary vasospasm alone, coronary embolism or vasculitis. MANA GEMENT OF ACUTE ST SE GMENT ELE VATI ON Diagnostic approach of STEMI   1) Clinical hx of ischaemic type chest pain 2) ECG 3) Serum cardiac biomarkers (myocardial injury or necrosis) Hx 1) Chest pain  –  retrosternal, severe, crushing, squeezing or pressing in nature, pain may radiate to the jaw or down the left upper limb (pain may be burning in nature and of lesser severity.) 2) Lasting > 30 min, 3) Associated with profuse sweating, nausea, vomiting and SOB. It is sometimes described as chest tightness only. 4) It may be in the epigastric region and be misinterpreted as indigestion or heart burn. 5) Rarely may it be localized to the back in the interscapular region only resulting in a misdiagnosis. 6) Other  –  unexplained nausea and vomiting, weakness, dizziness, light-headedness and syncope, which may occur in the presence or absence of chest pain. 7) Diabetics, the elderly and females may not present with typical chest pains dyspnoea and atypical chest pains. 8) PMH: Previous history of IHD, PCI or CABG Risk factors for atherosclerosis Symptoms suggestive of previous TIA or other forms of CVS disease Symptoms suggestive of peripheral vascular disease ECG 1) Hyperacute changes of a tall peaked T-wave, ST segment elevation followed by the development of Q-wave, return of the ST segment to isoelectric and T-wave inversion. 2) The cut off points for new or presumed new ST segment elevation ≥ 0.2mV in V1/V2/V3 and ≥ 0.1m V in other leads. This should be present in ≥2 contiguous leads.  3) The presence of new onset or presumably new LBBB in a patient with typical type chest pain indicates an INFARCT. Inferior STEMI  **However in early MI, the ECG may be normal or equivocal. Patients with continuous chest pain and in whom the clinical index of suspicion of STEMI is high, 12 lead ECG tracings repeated at close intervals of at least 15 min might show evolving changes. Comparison with previous ECG’s may also be helpfu l in such situations. In patients with an inferior infarct, one should look for associated posterior, lateral and RV infarct. The latter requires right sided chest leads for diagnosis. Serum Cardiac Biomarkers Confirm the diagnosis of STEMI. One should not, however, wait for the results of these biomarkers before initiating reperfusion therapy. Cardiac biomarkers: a) Cardiac troponins (cTnT and cTnI) b) Creatine kinase-Myocardial Band (CK-MB) c) Creatine kinase (CK) d) Myoglobin e) Fatty Acid Binding Proteins CT and CK-MB are the most specific cardiac biomarkers. It takes about 3-8 hrs after STEMI for them to rise. Thus, too early a measurement may result in a misleadingly low level. Diagnosis STEMI  –  CK-MB should be 2X the upper limit of normal. Persistently elevated values of CK-MB are almost never due to myocardial necrosis. CK-MB rises early and falls early. Hence, CKMB measurements are useful for the diagnosis of reinfarction. CK is not as sensitive or as specific as CK-MB. Nevertheless, it is also useful for the diagnosis of STEMI and reinfarction. CTnT / CTnI  –  sufficient to indicate myocardial necrosis. They are useful in detecting MI in patients presenting with atypical histories and non- diagnostic ECG’s.  Troponin levels are more important for the diagnosis of NSTEMI than STEMI. Troponins may remain elevated for up to 14 days. Not useful for the diagnosis of reinfarction. It is recommended that measurement of cardiac biomarkers be done at periodic intervals, at hospital admission and again at 12-24 hours. This would help to establish or exclude the diagnosis and may be useful for an estimation of infarct size. AST and LDH levels are not sensitive or specific for AMI with frequent false positive elevations. GMENT ELE VATI ON   Other Diagnostic Modalities CXR, Echocardiography  –  useful bedside imaging technique in difficult diagnostic situations. multislice computed tomography (MSCT) and radionuclide techniques TRO or confirm the presence of acute infarction or ischaemia. Identify non-ischaemic conditions causing chest pain such as valvular heart disease, pulmonary embolism, aortic dissection and pneumothorax. Identify mechanical complications of acute infarction. Provide prognostic information. Difficult Diagnosis?? ≈2 -8% of patients presenting with chest pains to the ED have been misdiagnosed and sent home. The morbidity and mortality in these patients is high. To reduce this misdiagnosis, we suggest the following measures be taken in all patients presenting with chest pains: They should be given priority in the emergency department and attended to urgently. Myocardial ischemia or infarction should be excluded in all these patients. Clinical suspicion should be high in all patients with predisposing risk factors for atherosclerosis. A careful history will often help in making the diagnosis. An ECG should be done as soon as possible in all patients with chest pains especially when the clinical suspicion of AMI is high. The threshold for doing an ECG in a patient presenting with chest pain should be low. Where the initial ECG is non- diagnostic, it should be repeated and compared with old ECG’s.  Cardiac biomarkers especially the troponins, are helpful in ruling in or ruling out a MI. Where the diagnosis is unclear but the clinical suspicion is high, these patients should be observed in the ED for a few hours and the resting ECG and cardiac biomarkers repeated to look for serial changes. If these remain stable, then the patient may be sent home but asked to return for an early review in the outpatient clinic. In addition, the hospital needs to: Educate all medical staff on the importance of early detection and treatment of AMI because this results in myocardial salvage and improved patient outcomes. Have regular refresher courses on ECG interpretation. Implement critical pathways for patients presenting with chest pains to the ED MANA GEMENT OF ACUTE ST SE GMENT ELE VATI ON MYOCARDIAL IN FAR CTI ON (STE MI) PRE-HOSPITAL MANAGEMENT Immediate measures to be taken in suspected cases of STEMI For the general public: Seek immediate medical attention at the nearest hospital. Call for an ambulance (dial 991 or hospital direct line if known) or get someone to take you immediately to the nearest hospital. Do not drive yourself.

j 236069

Jul 23, 2017
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks