 In the chronic stage , treatment involves managing the clinical manifestations of the disease . For example , <unk> and <unk> for irregular <unk> , such as the anti @-@ <unk> drug <unk> , may be life saving for some patients with chronic cardiac disease , while surgery may be required for <unk> . The disease cannot be cured in this phase , however . Chronic heart disease caused by Chagas disease is now a common reason for heart transplantation surgery . Until recently , however , Chagas disease was considered a <unk> for the procedure , since the heart damage could recur as the parasite was expected to seize the opportunity provided by the <unk> that follows surgery . 
