Objectives These studies sought to investigate the impact on mortality of coronary flow after passage
of the wire through the culprit vessel in patients with ST-segment elevation myocardial infarction
(STEMI) undergoing mechanical reperfusion.
Background Reduced spontaneous coronary flow before percutaneous coronary intervention influences
mortality in patients with STEMI. Response to vessel wiring in patients with an occluded coronary artery before
intervention might further discriminate outcomes irrespective of pre- and post-intervention coronary flow.
Methods Data from the STRATEGY (Single High-Dose Bolus Tirofiban and Sirolimus-Eluting Stent Versus Abciximab
and Bare-Metal Stent in Acute Myocardial Infarction) and MULTISTRATEGY (Multicenter Evaluation of
Single High-Dose Bolus Tirofiban Versus Abciximab With Sirolimus-Eluting Stent or Bare-Metal Stent in Acute
Myocardial Infarction Study) trials were pooled: of 919 index procedures, 902 films (98%) were technically adequate
for core laboratory TIMI (Thrombolysis In Myocardial Infarction) flow determination.
Results TIMI flow grade 0 was present before percutaneous coronary intervention in 59% of infarct vessels,
TIMI flow grade 1 to 2 was found in 21%, whereas the remainder of infarct arteries presented with
TIMI flow grade 3. In 49% of patients who showed persistent TIMI flow grade 0 after wire insertion (AWI),
mortality was higher at 30 days (5.3%) and 1 year (9.4%) compared with patients in whom TIMI flow
grade before percutaneous coronary intervention was either
0 (0.8%; p  0.003 and 3.6%, p  0.008)
or improved from 0 AWI (1.5%, p  0.04 and 3.6%, p  0.02). After correcting for multiple imbalances,
including baseline and final flow, persistent TIMI flow grade 0 AWI remained associated at 30 days to
2-fold (risk ratio [RR]: 2.1, 95% confidence interval [CI]: 1.08 to 5.00; p  0.038) and at 1 year to almost
3-fold increases of mortality (RR: 2.7, 95% CI: 1.3 to 5.6; p  0.008).
Conclusions STEMI patients displaying persistent no-flow AWI have a lower survival rate despite an apparently
successful mechanical intervention. As an early marker for high residual mortality risk, persistent
no-flow AWI may qualify STEMI patients for dedicated pharmacomechanical treatment strategies. (J Am
Coll Cardiol Intv 2011;4:51–62) © 2011 by the American College of Cardiology Foundation