Predictors of infarct-related artery patency following combined lytic therapy in patients with ST-segment elevation myocardial infarction treated with immediate percutaneous coronary intervention.

BACKGROUND AND AIM

Patency of infarct-related artery (IRA) before percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) is associated with better outcomes. Little is known of the clinical or angiographic predictors of IRA recanalisation after administration of combined fibrinolytic therapy before PCI.

METHODS

A total of 225 STEMI patients, admitted to remote hospitals with anticipated transfer time to cathlab > 90 min were enrolled. All patients received a half dose of alteplase and a full dose of abciximab at the remote hospital and were immediately transferred for angiography. In angiographic analysis, the culprit lesion (CL) was defined as the minimal lumen diameter (MLD) point in IRA (CLMLD) (in group with occluded IRA, measurement was done after the first pass of the guidewire).

RESULTS

Occluded IRA (TIMI 0+1) was found in 14.2% of patients (n = 32) and patent IRA (TIMI 2+3) in 85.8% (n = 193) at baseline angiography. Baseline and angiographic characteristics were similar in both groups, except for a higher rate of smoking in the TIMI 2+3 group (73.1% vs 50%; p = 0.009) and longer distance from CLMLD point to the nearest proximal side branch in the TIMI 0+1 group (21.2 ± 10.3 mm vs 13.8 ± 11.2 mm; p = 0.002). In multivariate analysis, smoking and distance from CLMLD to the nearest proximal side branch were independent predictors of IRA patency at baseline.

CONCLUSIONS

Angiographic (anatomical) IRA parameter as distance from CLMLD point to nearest proximal side branch may influence the efficacy of combined fibrinolytic therapy before PCI despite the similar clinical characteristics and time delay to angiography. Smoking has a paradoxical beneficial effect on combined thrombolytic therapy effectiveness.