Influence of balloon pressure inflation in patients undergoing primary coronary stent implantation during acute myocardial infarction. A quantitative coronary angiography analysis.

OBJECTIVE To verify the influence of moderate- or high-pressure balloon inflation during primary coronary stent implantation for acute myocardial infarction. METHODS After successful coronary stent implantation, 82 patients were divided into 2 groups according to the last balloon inflation pressure: group 1 (> or = 12 to < 16 atm) and group 2 (> or = 16 to 20 atm), each with 41 cases. All patients underwent late coronary angiography. RESULTS In group 1, the mean stent deployment pressure was 13.58 +/- 0.92 atm, and in the group 2 it was 18.15 +/- 1.66 atm. Stents implanted with moderate pressures (> or = 12 to < 16 atm) had a significantly smaller post-procedural minimal lumen diameter, compared to with those with higher pressure, with lesser acute gain (2.7 +/- 0.4 mm vs 2.9 +/- 0.4 mm; p = 0.004), but the late lumen loss (0.9 +/- 0.8 mm vs 0.9 +/- 0.6 mm) and the restenosis (22% vs. 17.1%) and target-vessel revascularization rates (9.8% vs 7.3%) were similar between the groups. CONCLUSION During AMI stenting, the use of high pressures (> or = 16 atm) did not cause a measurable improvement in late outcome, either in the late loss, its index, and the net gain, or in clinical and angiographic restenosis rates.