Relationship of the TIMI myocardial perfusion grades, flow grades, frame count, and percutaneous coronary intervention to long-term outcomes after thrombolytic administration in acute myocardial infarction.
BACKGROUND
Although 90-minute TIMI flow grades (TFGs), corrected TIMI frame counts (CTFCs), and TIMI myocardial perfusion grades (TMPGs) have been associated with 30-day outcomes, we hypothesized that these indices would be related to long-term outcomes after thrombolytic administration.


RESULTS
As a substudy of the TIMI 10B trial (tissue plasminogen activator versus tenecteplase), 49 centers carried out 2-year follow-up. TIMI grade 2/3 flow (Cox hazard ratio [HR] 0.41, P=0.001), reduced CTFCs (faster flow, P=0.02), and an open microvasculature (TMPG 2/3) (HR 0.51, P=0.038) were all associated with improved 2-year survival. Rescue percutaneous coronary intervention (PCI) of closed arteries (TFG 0/1) at 90 minutes was associated with reduced mortality (P=0.03), and mortality trended lower with adjunctive PCI of open (TFG 2/3) arteries (P=0.11). In a multivariate model correcting for previously identified correlates of mortality (age, sex, pulse, left anterior descending coronary artery infarction, and any PCI during initial hospitalization), patency (TFG 2/3) (HR 0.32, P<0.001), CTFC (P=0.01), and TMPG 2/3 remained associated with reduced mortality (HR 0.46, P=0.02).


CONCLUSIONS
Both improved epicardial flow (TFG 2/3 and low CTFCs) and tissue-level perfusion (TMPG 2/3) at 90 minutes after thrombolytic administration are independently associated with improved 2-year survival, suggesting complementary mechanisms of improved long-term survival. Although rescue PCI reduced long-term mortality, improved microvascular perfusion (TMPG 2/3) before PCI was also related to improved mortality independently of epicardial blood flow and the performance of rescue or adjunctive PCI. Further prospective trials are warranted to re-examine the benefit of early PCI with thrombolysis.
Gibson
C Michael
CM
TIMI Study Group, Department of Medicine, Brigham and Women's Hospital, Boston, Mass 02215, USA. mgibson@perfuse.org
Cannon
Christopher P
CP
Murphy
Sabina A
SA
Marble
Susan J
SJ
Barron
Hal V
HV
Braunwald
Eugene
E
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D017023:Coronary Angiography / Q000379:methods*; D003326:Coronary Circulation / Q000187:drug effects; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D010496:Pericardium / Q000000981:diagnostic imaging; D011379:Prognosis; D015996:Survival Rate; D000077785:Tenecteplase; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D016896:Treatment Outcome
D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator; D000077785:Tenecteplase