Background: Tissue perfusion during acute myocardial infarction (AMI) may be assessed by means of the angiographic method -- TIMI myocardial perfusion (TMP). We hypothesised that TMP grade (TMPG) after primary coronary angioplasty (PCI) implicates immediate and long-term clinical outcomes.
Methods: We studied 588 consecutive patients (mean age 58.7+/-10.8 years) with ST-segment elevation AMI treated with PCI. Infarct-related TMPG was evaluated before and after PCI. Myocardial injury was expressed as an area under the curve (AUC) of CK-MB release in the first 48 hours of reperfusion. Left ventricular ejection fraction (LVEF) was assessed by 2-dimensional echocardiography one day after PCI. Clinical end-points during a 12-month follow-up included death, recurrent MI and repeated revascularisation or hospitalisation. At the end of the follow-up, NYHA functional class was evaluated in all patients.
Results: Before PCI, TMPG -3, -2 and -0/1 values were observed in 52 (8.8%), 77 (13.1%) and 459 (78.1%) patients, respectively. After PCI, TMPG-3, -2 and -0/1 were achieved in 196 (33.3%), 174 (29.6%) and 218 (37.1%) patients, respectively. Patients with TMPG-3, -2, and -0/1 had AUC of 10341+/-1194, 12330+/-1272 and 16718+/-1860 (U/l x h) (p<0.01) and LVEF of 53.6+/-8.6%, 45.5+/-9.5% and 41.7+/-10.4% (p<0.001), respectively. In-hospital mortality rate in patients with TMPG-3, -2 and -0/1 was 0%, 4% and 11.9%, respectively (p<0.001), and after 12-months - 2%, 6.3% and 16.5%, respectively (p<0.001). The event-free survival rate after 1-year was 83.2%, 74.1% and 65.1% respectively (p<0.001). The percentage of patients in NYHA class > or =2 was 10.2%, 16.1% and 20.6% (p=0.003), respectively.
Conclusions: The TIMI myocardial perfusion grade after primary coronary angioplasty in acute myocardial infarction effects left ventricular injury and function as well as early and long-term clinical outcome.