IABP implantation
The patients were punctured in the right or left femoral artery, which were placed a 40mL IABP catheter through the 8F sheath with air drained in the 2cm below the opening of the left subclavian artery. At the same time, the catheter was connected to the IABP (IABP System 98; Datascope; Fairfield, NJ) machine. The ratio of counter pulsation frequency and heart rate ranged from 1:1 to 1:2. The IABP might be removed for those with urine volume> 30 mL/h, heart rate < 100 times /min, ventricular prephase contraction < 6 times /min.