PIK3C2A and cardiac arrhythmia: Some previous studies (Pulignano et al. 1998, Akyildiz et al. 2009, Rajabi 2014) have reported increasing in cardiovascular enzymatic markers such as CPK, CK-MB and LDH after black widow spider venom injection, which are the indicators of myocardial injury, heart muscle inflammation and arrhythmia.