Remote Ischaemic Preconditioning in Childhood Cancer

Overview

Survival rates of children with cancers have improved significantly in the recent few decades. Nonetheless, the side effect of this class of drugs on heart function remains to be an issue of concern. Exploration of new strategies to protect the heart in the long term is therefore of paramount importance in children undergoing treatment of cancers. Previous cardioprotective interventions hav focused on changing the formulation or rate of administration of anthracyclines but with no observable benefits. While dexrazoxane, an iron chelator, has shown to reduce cardiotoxic outcomes, there remains worries of an association between dexrazoxane use and an increased risk of developing secondary malignancies. Recently, the clinical application of remote ischaemic preconditioning (RIPC) as a non-invasive and an easily applicable non-pharmacological myocardial protective intervention has gained increasing interest. Remote ischaemic preconditioning is the phenomenon in which brief episodes of reversible ischaemia and reperfusion applied to one vascular bed render resistance to ischaemia reperfusion injury of tissues and organs distant away. It can be achieved by repeated 5-minute cycles of inflation and deflation of blood pressure cuff placed over the arm or leg to induce limb ischaemia and reperfusion injury. It is noteworthy that anthracycline cardiotoxicity and myocardial reperfusion injury occur through similar pathways. Hence, the investigators hypothesize that RIPC may reduce myocardial injury in children receiving anthracycline chemotherapy for childhood malignancies. The proposed study aims to conduct a parallel-group blinded randomized controlled trial study to investigate whether RIPC may reduce heart damage in childhood cancer patients undergoing anthracycline-based treatment, and to determine the effect of RIPC on the changes in levels of cardiac troponin T, and on the occurrence of clinical cardiovascular events and echocardiographic indices.

Remote ischemic preconditioning (RIPC) protocol will be induced at baseline and before each dose of anthracycline cardiac surgery and once before induction of anesthesia by 3 cycles of 5-min upper or lower limb ischemia and 5-min reperfusion using a blood-pressure cuff inflated to 15 mmHg above the systolic blood pressure for 5 minutes followed by 5 minutes of cuff deflation to 0 mmHg.