The Universal Definition of Myocardial Infarction 3 rd revision, 2012 Joseph S. Alpert, MD Professor of Medicine, University of Arizona College of Medicine, Tucson, AZ; Editor-in-Chief, American Journal of Medicine
Potential Conflicts of Interest: 1. No major conflicts of interest, i.e., all honoraria < $5,000; 2. Consultations - current or previous: Sanofi-Aventis, Merck, Bristol-Myers-Squibb, Pfizer, Astra- Zeneca, McNeill, Organon, Berlex, Novartis, Ciba-Geigy, Exeter CME; North American Center for Continuing Medical Education (NACCME), Servier, Johnson & Johnson, Bayer, Daiichi Sankyo, Omnia CME, Duke Clinical Research Institute, TIMI, Janssen, Boehringer Ingleheim.
HOW DID IT ALL START?
Myocardial Infarction Redefined 1998 Kristian Thygesen, FESC, FACC Aarhus University Hospital Aarhus, Denmark Joseph S. Alpert, FACC, FESC University of Arizona Health Science Center Tucson, AZ, USA
COMPARING APPLES AND ORANGES
Define in Webster s Unabridged Dictionary To determine the essential quality of a thing
The Diagnostic Triad for AMI Pain ECG Serum Markers
The Criteria The Criteria for the diagnosis of acute MI as established by WHO, included 2 of the following 3: History: Chest discomfort or equivalent Diagnostic changes on ECG Elevated cardiac enzymes (or markers)
The WHO Definition from the 1970 s Based on epidemiological principles Non-specific Did not use biomarkers early on; later biomarker use was not standardized Not clinician friendly
Changing Criteria for the Definition of Myocardial Infarction Primarily ECG approach Primarily Biomarker Approach First WHO Def Fifth WHO Def WHO Monica Def ESC-ACC Redef Univ MI Def Third Univ MI Def 1960 1970 1980 1990 2000 2010 2020
Universal Definition of Myocardial Infarction Consensus Documents 2000 2007 2012
Third Universal Definition of Myocardial Infarction Simultaneous Publications European Heart Journal Online 24 August 2012, in print October 2012; 33: 2551-2567 Circulation October 16, 2012; 60:1581-1598 Journal of American College of Cardiology October 16, 2012; 126: 2020-2035 Nature Reviews Cardiology - November 9, 2012; 11: 620-33 Global Heart
Definition of Myocardial Infarction Pathology Acute myocardial infarction is defined as myocardial cell death due to prolonged myocardial isch(a)emia.
Biomarkers for Detection of Myocardial Infarction Preferably Detection of rise and/or fall of cardiac Troponin (I or T) with at least one value above the 99 th percentile of the upper reference limit measured with a coefficient of variation 10%. When cardiac troponin is not available Detection of rise and/or fall of CKMB mass with at least one value above the 99 th percentile of the upper reference limit measured with a coefficient of variation 10%.
Criteria for Acute Myocardial Infarction Detection of a rise and/or fall of cardiac biomarker values (preferably cardiac troponin (ctn) ) with at least one value above the 99 th percentile upper reference limit (URL) and with at least one of the following: Ischemic symptoms ECG changes of new ischemia (new ST-T changes or new LBBB) Development of pathologic Q waves in the ECG Imaging evidence of new loss of viable myocardium or new regional wall motion abnormality Identification of an intracoronary thrombus by angiography or autopsy
Criteria for Prior Myocardial Infarction Pathological Q waves with or without symptoms in the absence of nonischemic causes Imaging evidence of a region of loss of viable myocardium that is thinned and fails to contract in the absence of a non-ischemic cause Pathological findings of a prior myocardial infarction
Elevations of Cardiac Troponin Values Because of Myocardial Injury Injury related to primary myocardial ischemia (MI type 1) Injury related to supply/demand imbalance of myocardial ischemia (MI type 2) Injury not related to myocardial ischemia Multifactorial or indeterminate myocardial injury
A myocardial injury is not an infarct because ischemia was not involved A myocardial injury is diagnosed when an abnormal ctn value is noted but the underlying mechanism of cardiac injury is not ischemia, for example, cardiac trauma. In many cases, for example, chronic renal failure and heart failure, the blood ctn values remain elevated rather than rising and/or falling. Although controversial, many of these troponin abnormalities are the result of myocardial injury and not type 2 MI.
Elevated Troponin in the Absence of Overt Ischemic Heart Disease Cardiac contusion, or other trauma including surgery, ablation, pacing etc Congestive heart failure acute and chronic Aortic dissection Aortic valve disease Hypertrophic cardiomyopathy Tachy- or brady arrhythmias, or heart block Apical ballooning syndrome (takatsubo syndrome) Rhabdomyolysis with cardiac injury Pulmonary embolism, severe pulmonary hypertension Renal failure Acute neurological disease, including stroke, or subarachnoid haemorrhage Infiltrative diseases, e.g., amyloidosis, hemochromatosis, sarcoidosis, and scleroderma Inflammatory diseases, e.g., myocarditis or myocardial extension of endo-/pericarditis Drug toxicity or toxins Critically ill patients, especially with respiratory failure, or sepsis Burns, especially if affecting > 30% of body surface area Extreme exertion
Non-cardiac major procedure Tachy-/bradyarrhythmia Cardiac procedure Heart failure Myocardial Infarction MIM Myocardial Injury Renal failure Myocardial injury with cell death marked by cardiac troponin elevation Clinical evidence of acute myocardial ischemia with rise and/or fall of cardiac troponin
Myocardial Infarction Type 1 Spontaneous myocardial infarction related to atherosclerotic plaque rupture, ulceration, fissuring, erosion, or dissection with resulting intraluminal thrombus in one or more coronary arteries leading to decreased myocardial blood flow or distal platelet emboli with ensuing myocyte necrosis. The patient may have underlying severe CAD but on occasion non-obstructive or no CAD. Third Universal Definition of Myocardial Infarction
Myocardial Infarction Type 2 In instances of myocardial injury with necrosis where a condition other than CAD contributes to an imbalance between myocardial oxygen supply and/or demand, e.g. coronary endothelial dysfunction, coronary artery spasm, coronary embolism, tachybrady-arrhythmia, an(a)emia, respiratory failure, hypotension or hypertension with and without LVH. Third Universal Definition of Myocardial Infarction
Differentiation between MI Types 1 and 2 according to the condition of the coronary arteries Plaque rupture with thrombus MI Type 1 Vasospasm or endothelial dysfunction Fixed atherosclerosis and supply-demand imbalance MI Type 2 MI Type 2 Supply-demand imbalance alone MI Type 2
Myocardial Infarction Type 3 Cardiac death with symptoms suggestive of myocardial ischaemia and presumed new ischaemic ECG changes or new LBBB, but death occurring before blood samples could be obtained, before cardiac biomarkers could rise, or in rare cases cardiac biomarkers were not collected. Third Universal Definition of Myocardial Infarction
Myocardial Infarction Type 4a Myocardial infarction associated with PCI is arbitrarily defined by elevation of ctn values >5 X 99 th percentile URL in patients with normal baseline ( 99 th percentile URL) or rise of ctn values >20% if the baseline values are elevated and stable or falling. In addition, either (i) symptoms suggestive of myocardial ischemia or (ii) new ischemic ECG changes or new LBBB, or (iii) angiographic finding of a procedural complication or (iv) imaging evidence of new loss of viable myocardium or new regional wall motion abnormality are required. Third Universal Definition of Myocardial Infarction R
Myocardial Infarction Type 4b Myocardial infarction related to stent-thrombosis is detected by coronary angiography or autopsy in the setting of myocardial ischemia and with a rise and/or fall of cardiac biomarkers with at least one value >99 th percentile URL. R
Myocardial Infarction type 4c Stent restenosis 50-60% or more with elevated troponin values (similar criteria to type 1) in the blood and clinical criteria.
Myocardial Infarction Type 5 Myocardial infarction associated with CABG is arbitrarily defined by elevation of ctn values >10 X 99 th percentile URL in patients with normal baseline ( 99 th percentile URL). In addition, either (i) new pathological Q waves or new LBBB, or (ii) angiographic documented new graft or new native coronary artery occlusion, or (iii) imaging evidence of new loss of viable myocardium or new regional wall motion abnormality. Third Universal Definition of Myocardial Infarction
Imaging Evidence of Acute Myocardial Infarction Imaging evidence of new loss of viable myocardium or new regional wall motion abnormality in the presence of elevated cardiac troponin values and in the absence of non-ischaemic causes.
Definition of Myocardial Infarction Special Categories Reinfarction An acute MI that occurs 28 days of an incident or a recurrent MI is termed reinfarction. Recurrent Myocardial Infarction An acute MI that occurs >28 days after an incident MI is termed recurrent MI. Silent Myocardial Infarction Asymptomatic patients who develop pathologic Q wave criteria for MI or reveal evidence of MI by cardiac imaging, that cannot be directly attributed to coronary revascularization should be termed silent MI.
Definition of Myocardial Infarction in Various Settings Assessment of myocardial injury or infarction in patients undergoing cardiac procedures, e. g. TAVI, mitral clip, ablation of arrhythmias Myocardial infarction associated with noncardiac procedures Myocardial injury or infarction in an intensive care unit Myocardial injury or infarction associated with heart failure
** Distinguishing myocardial infarction type 1 or type 2 from myocardial injury: Was the injury due to ischemia or another process? **If it is an MI, what was the underlying pathophysiologic mechanism leading to the MI: plaque rupture or a change in MVO2 demand or supply or a non-ischemic injury?
Pathologic entities in the 2012 document where it may be necessary to differentiate between type 1, type 2 MI, and a myocardial injury Heart failure and abnormal blood troponin levels. Renal failure and abnormal blood troponin levels. Critically ill medical patients with abnormal blood troponin levels. Other procedures, cardiac and non-cardiac with abnormal blood troponin levels.
Careful clinical thought and judg(e)ment must be employed if the universal definition is to be used correctly.
Does the patient have to have CAD to be diagnosed with an MI? Suggested diagnostic terminology in patients with or without a high likelihood of having CAD: 1. Myocardial infarction, type 2, with preexisting CAD ; 2. Myocardial infarction, type 2 with likely CAD present ; 3. Myocardial infarction, type 2 with CAD not present or very unlikely.
In summary, there will be a number of changes to the 2007 MI definition document, however, troponin measurement will still be the gold standard for the universal definition.
The End