Remote preconditioning, perconditioning, and postconditioning: a comparative study of their cardio-protective properties in rat models

OBJECTIVE: Ischemia reperfusion injury is partly responsible for the high mortality associated with induced myocardial injury and the reduction in the full benefit of myocardial reperfusion. Remote ischemic preconditioning, perconditioning, and postconditioning have all been shown to be cardioprotective. However, it is still unknown which one is the most beneficial. To examine this issue, we used adult male Wistar rat ischemia reperfusion models to compare the cardioprotective effect of these three approaches applied on double-sided hind limbs. METHODS: The rats were randomly distributed to the following five groups: sham, ischemia reperfusion, remote preconditioning, remote perconditioning, and remote post-conditioning. The ischemia/reperfusion model was established by sternotomy followed by a 30-min ligation of the left coronary artery and a subsequent 3-h reperfusion. Remote conditioning was induced with three 5-min ischemia/5-min reperfusion cycles of the double-sided hind limbs using a tourniquet. RESULTS: A lower early reperfusion arrhythmia score (1.50 + 0.97) was found in the rats treated with remote perconditioning compared to those in the ischemia reperfusion group (2.33 + 0.71). Meanwhile, reduced infarct size was also observed (15.27 + 5.19% in remote perconditioning, 14.53 + 3.45% in remote preconditioning, and 19.84+5.85% in remote post-conditioning vs. 34.47 + 7.13% in ischemia reperfusion, p<0.05), as well as higher expression levels of the apoptosis-relevant protein Bcl-2/Bax following global (ischemia/reperfusion) injury in in vivo rat heart models (1.255 + 0.053 in remote perconditioning, 1.463 + 0.290 in remote preconditioning, and 1.461 +0.541 in remote post-conditioning vs. 1.003 + 0.159 in ischemia reperfusion, p<0.05). CONCLUSION: Three remote conditioning strategies implemented with episodes of double-sided hind limb ischemia/reperfusion have similar therapeutic potential for cardiac ischemia/reperfusion injury, and remote perconditioning has a greater ability to prevent reperfusion arrhythmia.

Percutaneous closure of a post-traumatic ventricular septal defect with a patent ductus arteriosus occluder

OBJECTIVE: Ventricular septal defects resulting from post-traumatic cardiac injury are very rare. Percutaneous closure has emerged as a method for treating this disorder. We wish to report our experience in three patients who underwent percutaneous closure of a post-traumatic ventricular septal defect with a patent ductus arteriosus occluder. METHODS: We treated three patients with post-traumatic ventricular septal defects caused by stab wounds with knives. After the heart wound was repaired, patient examinations revealed ventricular septal defects with pulmonary/systemic flow ratios (Qp/Qs) of over 1.7. The post-traumatic ventricular septal defects were closed percutaneously with a patent ductus arteriosus occluder (Lifetech Scientific (Shenzhen) Co., LTD, Guangdong, China) utilizing standard techniques. RESULTS: Post-operative transthoracic echocardiography revealed no residual left-to-right shunt and indicated normal ventricular function. In addition, 320-slice computerized tomography showed that the occluder was well placed and exhibited normal morphology. CONCLUSION: Our experiences indicate that closure of a post-traumatic ventricular septal defect using a patent ductus arteriosus occluder is feasible, safe, and effective.