Chagas CardiomyopathyTrypanosoma cruziTrypanocidal AgentsChagas DiseaseChronic DiseaseHeartHeart DiseasesTriatomaTriatominaeHeart RateHeart Defects, CongenitalCoronary DiseaseBoliviaInsect ControlRhodniusRheumatic Heart DiseaseNitroimidazolesHeart FailureNifurtimoxInsect VectorsMyocardial IschemiaRisk Factors