Transesophageal Pacing Cardiac Induces Cardiac Arrest and Subsequent Brain Injury in Rats

BACKGROUNDIt was reported that >356,000 individuals in the United States [1] and 544,000 individuals in China [2] suffer from Out-of-Hospital Cardiac Arrest (OHCA) annually.In the United States only about 11% patients survive to discharge; however, poor neurological outcome is often observed.Additionally, only 1-3% patients who suffer from OHCA in China could survive to discharge.At present, there is no effective treatment for cerebral resuscitation after Cardiac Arrest (CA) other than Target Temperature Management (TTM) which has been reported to have therapeutic effects on cerebral injury following CA in clinical trials [3].TTM during cerebral resuscitation post-CA has been investigated [3-6]; however, opposing findings have been reported [7][8][9].In the past few decades, various models of CA have been employed, including lethal arrhythmia-induced CA types, such as the Ventricular Fibrillation-induced CA (VFCA) model (54%), and the asphyxial CA (25%), potassium chloride-induced CA (8%) and exsanguination CA models [10].As various models of CA are used, there is a high degree of heterogeneity; thus, opposing results may be obtained.It is important to establish a stable and reproducible animal model for investigations into organ injury and protection post-CA.Arrhythmia, particularly VF, is the most common cause of sudden patient mortality in clinical situations [11,12].Therefore, the lethal arrhythmia-induced CA model may be more appropriate for investigations of CA and post-CA syndrome than other models in translational medicine.It is well reported that rat models of CA are advantageous as they are low cost and easy to apply for screening analysis that requires large quantities of animals.Rat models have been widely used in behavioral studies to assess neurological outcome.Thus, rat models of CA induced by electrical stimulation may be more suitable for studying cerebral resuscitation post-CA.Models of induced-CA have been generated via different approaches, including stimulation of the right ventricular endocardium, or esophagus and chest, and transcutaneous electrical stimulation of the epicardium; however, the experimental procedures are difficult to perform [13][14][15][16].