question: Hi thereI need some information regarding a "battery implantation for heart"currently, my auntie has a problem with her heartaccording to doctor in my area, she needs a battery implantation in order to making her heart back functioing normallythe doctor mention that her heart working only 21 percent (I dont have any idea what its mean by this)my auntie seems healthy, but when i heard her heart is working only 21 percent, I start to worry about itcan someone please tell me what is battery implantation?pleasee