Early noninvasive identification of failed reperfusion after intravenous thrombolytic therapy in acute myocardial infarction.
OBJECTIVE
This study sought to evaluate a biochemical approach to the early noninvasive assessment of reperfusion.


BACKGROUND
In patients with an acute myocardial infarction, a rapid noninvasive method of detecting failure of intravenous thrombolytic therapy to restore early Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in the infarct-related artery (IRA) is needed.


METHODS
Serial blood samples were collected to assay creatine kinase-MB fraction (CKMB mass), cardiac troponin T and myoglobin concentrations in 105 patients with a myocardial infarction who underwent early angiography after intravenous streptokinase. The ratios of the 60- and 90-min concentrations to prethrombolytic values were used to determine an index that could identify failure to achieve TIMI grade 3 flow in the IRA at 90 min.


RESULTS
Significant increases in serum concentrations of markers at 60 min were more likely with TIMI grade 3 flow (59 patients) than with TIMI grade 0 to 2 flow (46 patients). Ratios < or = 5 at 60 min after thrombolysis detected failure to achieve 90-min TIMI grade 3 flow with 92% to 97% sensitivity, 43% to 60% specificity and 63% to 76% positive and 86% to 94% negative predictive values. Ratios < or = 10 at 90 min showed 88% to 95% sensitivity, 49% to 65% specificity and 61% to 69% positive and 86% to 94% negative predictive values for TIMI flow grade < 3. The overall predictive values were thus similar for all three markers.


CONCLUSIONS
In acute myocardial infarction treated with intravenous streptokinase, a simple measurement of increased serum concentrations of CKMB mass, cardiac troponin T or myoglobin at 60 and 90 min can accurately predict failure to achieve TIMI grade 3 flow in the IRA at 90 min.
Stewart
J T
JT
Department of Cardiology, Green Lane Hospital, Auckland, New Zealand. Jims@ahsl.co.nz
French
J K
JK
Théroux
P
P
Ramanathan
K
K
Solymoss
B C
BC
Johnson
R
R
White
H D
HD
D000368:Aged; D015415:Biomarkers; D003402:Creatine Kinase / Q000097:blood; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy*; D015425:Myocardial Reperfusion; D009211:Myoglobin / Q000097:blood; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013300:Streptokinase / Q000627:therapeutic use*; D013997:Time Factors; D017211:Treatment Failure; D014336:Troponin / Q000032:analysis; D020107:Troponin T
D015415:Biomarkers; D005343:Fibrinolytic Agents; D007527:Isoenzymes; D009211:Myoglobin; D014336:Troponin; D020107:Troponin T; D003402:Creatine Kinase; D013300:Streptokinase