Statistical analysis and power calculation: Sample size: assuming an absolute difference (delta) of 4 mm in the change of ST-segment shift from the first to the second balloon inflation between the 2 groups, we calculated that 30 patients per group will be required to have an 80% power to detect a statistically significant difference between groups at p < 0.05. Standard deviation (SD) of the primary endpoint is expected to be ~ 5,4 mm in each treatment group. A total of 66 patients will be enrolled considering a total drop-out rate of 10%.