Temporal changes in TIMI myocardial perfusion grade in relation to epicardial flow, ST-resolution and left ventricular function after primary percutaneous coronary intervention.

BACKGROUND

Myocardial perfusion at the end of reperfusion therapy assessed angiographically with thrombolysis in myocardial infarction (TIMI) myocardial perfusion grade (TMPG) has been associated with recovery of left ventricular (LV) function and survival. The aim of this analysis was to study the evolution of TMPG within the first week following primary percutaneous coronary intervention (PCI) and its association with ECG-derived ST-segment resolution (STRES) and recovery of LV function.

METHODS

A total of 76 patients with acute myocardial infarction were pretreated with enoxaparine and abciximab and subjected to primary PCI within a prospective study and evaluated with TMPG assessed on coronary angiography at the end of the procedure and after 5-7 days. STRES was evaluated at 120 min post inclusion and global LV function was assessed by echocardiography after 30 days.

RESULTS

Reperfusion (TIMI flow 2-3) was reached in all patients. Forty one percent had 'open myocardium' (i.e. TMPG 2 or 3) after PCI, a number that increased to 61% after 5-7 days (P=0.003). STRES >50% was reached in 73% of the patients and there was a good correlation between TMPG and STRES. Furthermore, those who improved from 'closed' to 'open myocardium' had higher STRES (and similar to those with 'open myocardium' already post-PCI) than those who had 'closed myocardium' at both occasions (80 vs. 52%, P=0.012).

CONCLUSION

A significant increase was found in the number of patients with 'open myocardium' within the first week post-primary PCI and STRES seems to predict this improvement.