Abstract 9512: Postconditioning With Lactate-Enriched Blood Potentiates the Protective Effect of Postconditioning Alone in Patients With Acute Myocardial Infarction
Objective: The infarct-limiting effect of postconditioning (PC) could not be shown in recent clinical trials. We tested the hypothesis that modification of the original protocol to increase the delay in recovery from intracellular acidosis would potentiate the protective effect of PC.
Methods: Consecutive 7 patients with acute MI in various stages of the condition underwent primary PCI by using the modified PC protocol in which the duration of each brief reperfusion was prolonged from 10 s to 60 s in a stepwise manner. Lactated Ringer’s solution (20-30 mL) containing 28 mM lactate was injected directly into the culprit coronary artery at the end of each brief reperfusion and the balloon was quickly inflated at the site of the lesion, whereby lactate could be trapped inside the ischemic myocardium. Each brief ischemic period lasted 60 s. After 7 cycles of balloon inflation and deflation, full reperfusion was performed. The aim of this protocol was to achieve controlled reperfusion with tissue oxygenation and minimal lactate washout. After these procedures, stenting was performed.
Results: All patients were successfully reperfused and experienced neither worsening of chest pain nor worsening of ST deviation during reperfusion. Reperfusion arrhythmia, including bradycardia, was not evoked by reperfusion in any of the 7 patients. TIMI grade flow III was achieved in all patients. Moreover, marked myocardial staining with contrast medium (area surrounded by white arrows) and/or early visualization of venous drainage (black arrows) were observed in all patients, indicating unimpaired microcirculation. The peak CK value (1074±1082 IU/L) was lower than expected in each situation. Radioisotope imaging revealed well-preserved myocardial viability in all patients.
Conclusion: PC with lactate-enriched blood consistently suppresses the various detrimental effects of reperfusion and potentiates the protective effect of postconditioning alone in patients with acute MI.
- © 2012 by American Heart Association, Inc.