Aim: To examine whether pulmonary artery balloon pulsation (PABP) could improve circulatory function in acute myocardial infarction (AMI) in pigs.
Methods/results: Ten downsize pigs were sedated and ventilated. AMI was induced by inserting a plug into the left anterior descending artery. A pulsation balloon was placed in the pulmonary artery in all animals. In the treatment group (TG), pulsations began when life-threatening arrhythmia or > 30% drop in mean blood pressure (MBP) or > 40% decrease in cardiac output compared to baseline occurred. Pulsation rate was 120/min, independent of the heartbeat, maintained for 10 min. The control group (CG) received no pulsation. In the TG (n = 5), mean BP after the AMI improved by 7 ± 12 mmHg after 150 min while in the CG, MBP decreased by 17 ± 25 mmHg, P < 0.05; coronary perfusion pressure improved by 8 ± 7 mmHg in the TG but decreased by 15 ± 12 in the CG (P < 0.05). In the CG, cardiac output did not change but in the TG it improved from 3.5 ± 0.9 after the AMI to 4.2 ± 1.1 l/min 150 min after AMI (P < 0.05). The TG required 1.8 ± 0.4 electric shocks for ventricular fibrillation versus 0.8 ± 0.4 in the pulsation group (P < 0.05).
Conclusion: PABP could be useful in the management of AMI due to improved mean arterial BP, coronary perfusion pressure, cardiac output and electrical stability. The mechanism of this effect remains to be determined.
Keywords: Acute myocardial infarction; left ventricular failure; life-threatening arrhythmia; pulmonary artery balloon pulsation.