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Guide to the TIMI Myocardial Blush 1. Blush should be assessed distal to the culprit lesion. 2. Views should be chosen to minimize superimposition of non-infarcted territories in the assessment of the culprit artery’s TMP Grade. 3. The duration of cinefilming should exceeded 3 cardiac cycles in the washout phase to assess the washout of the myocardial blush. This would require filming for approximately 5 to 6 cardiac cycles (5 to 6 seconds). 4. Care should be taken not to mistake filling of the venous system such as the great cardiac vein as blush. This appears as a linear vascular structure rather than as a diffuse or round collection of dye. 5. Blush should be assessed during the same phase of the cardiac cycle as it may be less intense during diastole. 6. Wait at least 30 seconds after you take test injections or "puffs" of the artery on fluoroscopy before cinefilming the injection used to assess the blush. If you film immediately after a "puff", there may be dye retention, and you may overestimate the incidence of TMPG 1. Definitions of TIMI Myocardial Perfusion GradesWe would recommend that you watch movies of the TIMI myocardial blush grades in the following order (most apparent blush to least apparent): Click here to view TIMI myocardial blush grade 1 Click here to view TIMI myocardial blush grade 2 Click here to view TIMI myocardial blush grade 3 Click here to view TIMI myocardial blush grade 0
TIMI Myocardial Perfusion Grade 0: Failure of dye to enter the microvasculature. Either minimal or no ground glass appearance (“blush”) or opacification of the myocardium in the distribution of the culprit artery indicating lack of tissue level perfusion. Click here to watch a movie of TIMI Myocardial Perfusion Grade 0. TIMI Myocardial Perfusion Grade 1: Dye slowly enters but fails to exit the microvasculature. There is the ground glass appearance (“blush”) or opacification of the myocardium in the distribution of the culprit lesion that fails to clear from the microvasculature, and dye staining is present on the next injection (approximately 30 seconds between injections). Click here to watch a movie of TIMI Myocardial Perfusion Grade 1. TIMI Myocardial Perfusion Grade 2: Delayed entry and exit of dye from the microvasculature. There is the ground glass appearance (“blush”) or opacification of the myocardium in the distribution of the culprit lesion that is strongly persistent at the end of the washout phase (i.e. dye is strongly persistent after 3 cardiac cycles of the washout phase and either does not or only minimally diminishes in intensity during washout). Click here to watch a movie of TIMI Myocardial Perfusion Grade 2. TIMI Myocardial Perfusion Grade 3: Normal entry and exit of dye from the microvasculature. There is the ground glass appearance (“blush”) or opacification of the myocardium in the distribution of the culprit lesion that clears normally, and is either gone or only mildly/moderately persistent at the end of the washout phase (i.e. dye is gone or is mildly/moderately persistent after 3 cardiac cycles of the washout phase and noticeably diminishes in intensity during the washout phase), similar to that in an uninvolved artery. Blush that is of only mild intensity throughout the washout phase but fades minimally is also classified as grade 3. Click here to watch a movie of TIMI Myocardial Perfusion Grade 3.
What view should I use to assess the blush? We have found the LAO view with cranial angulation to be the optimal view for the RCA. If the RAO view is used, then the heart muscle will be viewed on end and will appear much brighter than in the LAO views. In general, do not use this view unless you have a sufficient visual library to know that the blush will be brighter in this view !!!! If you use this view you will tend to overestimate the incidence of TMPG 2! By far, the best view to assess the LAD and the circumflex in is the left lateral projection on 9 inch mode. Otherwise, in the RAO caudal view, there can be overlap of the LAD blush by that in the diagonal. It is for this reason that we prefer the RAO cranial view with extreme cranial angulation to minimize overlap by the circumflex. The blush will be seen lying below the LAD in the septal branches and above the LAD in the diagonals. Because of a lack of overlap, the RAO cranial view of the LAD is often the optimal view of the LAD. The LAO cranial view can also be used. In this view the blush is often brightest to the left of the LAD in the distribution of the septal branches. The LAD blush will often appear brighter in this view because of superimposition of the myocardium. In the spider view (the LAO caudal), the blush in the LAD can be compared to that in the circumflex. However, be aware that the blush of both arteries will be brighter than in other views because you are "looking down the barrel" of the heart, and there is a large amount of superimposition of myocardium in this view. This view is good for comparing the relative blush in the LAD and the Circumflex, but it is not optimal for assessing the absolute brightness of the LAD or Circumflex blush because you are looking at the heart muscle on end. Do not use this view as you will overestimate the incidence of TMPG 2. The Circumflex: Otherwise, the optimal view of the circumflex is the RAO caudal. Be certain that there is minimal overlap by blush in the LAD or diagonals. In the spider view (the LAO caudal), the blush in the Circumflex can be compared to that in the LAD. However, be aware that the blush of both arteries will be brighter than in other views because you are "looking down the barrel" of the heart, and there is a large amount of superimposition of myocardium in this view. This view is good for comparing the relative blush in the LAD and the Circumflex, but it is not optimal for assessing the absolute brightness of the LAD or Circumflex blush because you are looking at the heart muscle on end. Do not use this view as you will overestimate the incidence of TMPG 2. |
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Last updated and edited 11/20/2004