Relationship of TIMI Myocardial Perfusion Grade to Mortality After Administration of Thrombolytic Drugs

Abstract

Background-Although improved epicardial blood flow (as assessed with either TIMI flow grades or TIMI frame count) has been related to reduced mortality after administration of thrombolytic drugs, the relationship of myocardial perfusion (as assessed on the coronary arteriogram) to mortality has not been examined. Methods and Results-A new, simple angiographic method, the TIMI myocardial perfusion (TMP) grade, was used to assess the filling and clearance of contrast in the myocardium in 762 patients in the TIMI (Thrombolysis In Myocardial Infarction) 10B trial, and its relationship to mortality was examined. TMP grade 0 was defined as no apparent tissue-level perfusion (no ground-glass appearance of blush or opacification of the myocardium) in the distribution of the culprit artery; TMP grade 1 indicates presence of myocardial blush but no clearance from the microvasculature (blush or a stain was present on the next injection); TMP grade 2 blush clears slowly (blush is strongly persistent and diminishes minimally or not at all during 3 cardiac cycles of the washout phase); and TMP grade 3 indicates that blush begins to clear during washout (blush is minimally persistent after 3 cardiac cycles of washout). There was a mortality gradient across the TMP grades, with mortality lowest in those patients with TMP grade 3 (2.0%), intermediate in TMP grade 2 (4.4%), and highest in TMP grades 0 and 1 (6.0%; 3-way Pϭ0.05). Even among patients with TIMI grade 3 flow in the epicardial artery, the TMP grades allowed further risk stratification of 30-day mortality: 0.73% for TMP grade 3; 2.9% for TMP grade 2; 5.0% for TMP grade 0 or 1 (Pϭ0.03 for TMP grade 3 versus grades 0, 1, and 2; 3-way Pϭ0.066). TMP grade 3 flow was a multivariate correlate of 30-day mortality (OR 0.35, 95% CI 0.12 to 1.02, Pϭ0.054) in a multivariate model that adjusted for the presence of TIMI 3 flow (PϭNS), the corrected TIMI frame count (OR 1.02, Pϭ0.06), the presence of an anterior myocardial infarction (OR 2.3, Pϭ0.03), pulse rate on admission (PϭNS), female sex (PϭNS), and age (OR 1.1, PϽ0.001). Conclusions-Impaired perfusion of the myocardium on coronary arteriography by use of the TMP grade is related to a higher risk of mortality after administration of thrombolytic drugs that is independent of flow in the epicardial artery.

Possible Participation of Endothelial Cell Apoptosis of Coronary Microvessels in the Genesis of Takotsubo Cardiomyopathy

“…The Thrombolysis in Myocardial Infarction (TIMI) myocardial perfusion grade was examined using angiograms obtained before and after acetylcholine administration. The grading was as follows: grade 0, minimal or no myocardial blush by intracoronary contrast material; grade 1, contrast material stains the myocardium, and this stain persists on the next injection; grade 2, contrast material enters the myocardium but washes out slowly; and grade 3, normal entrance and exit of contrast material 12 in the ballooning apical segment.…”

Relationship of Admission QRS Duration and Changes in QRS Duration With Myocardial Reperfusion in Patients With Acute ST Segment Elevation Myocardial Infarction (STEMI) Treated With Fibrinolytic Therapy

“…13 TIMI myocardial perfusion (TMP) grade was determined on angiogram by 2 blinded experienced interventional cardiologists based on the visual assessment of contrast opacification of the myocardial territory subtended by the IRA or the vessel supplying collateral channels to the IRA, in the cases when occluded IRA was present, as previously described. 10 If discordance regarding TMP grade was present, a third reader's opinion was sort. TMP grade was defined as follows: (0) no myocardial blush or contrast density; (1) minimal myocardial blush or contrast density; (2) moderate myocardial blush or contrast density but less than that obtained during angiography of a contralateral or ipsilateral non-IRA; and (3) normal myocardial blush comparable with that obtained during angiography of a contralateral or ipsilateral non-IRA.…”

“…TMP grades 0 and 1 were taken as indicators of injured microvasculature and TMP grades 2 and 3 were taken as indicators of preserved microvasculature, as previously described. 10 …”

“…As the surrogate of tissue level reperfusion, we used angiographic myocardial blush grade, which was shown to be a reliable index of microvascular integrity in previous reports. [8][9][10][11] …”

Coronary Thermodilution Waveforms After Acute Reperfused ST‐Segment–Elevation Myocardial Infarction: Relation to Microvascular Obstruction and Prognosis

“…Standard measures of myocardial reperfusion, including TIMI (Thrombolysis in Myocardial Infarction) Myocardial Perfusion Grade and corrected frame count, or ST‐segment resolution on the ECG, lack sensitivity and reproducibility 6, 7, 8, 9. CMR is the reference noninvasive technique for detection of microvascular pathology3, 5, 10; however, CMR is neither feasible acutely nor widely available1 and is not routinely recommended in contemporary practice guidelines 1, 11…”