Chagas disease (CD) is considered a typical low-income population sickness of the developing countries in Latin America. Given the historical relevance of CD in individuals in southern Rio Grande do Sul (RS) State, Brazil, the aim of this study was to identify the knowledge of the CD and its vectors by cardiac patients, and the prevalence of anti-T cruzi antibodies in these individuals in Pelotas, city located in Rio Grande do Sul (RS) state, Brazil. The subjects with cardiac disease were submitted to a semi-structured questionnaire as well as two serological tests in order to detect anti-T. cruzi IgG antibodies. Of the individuals that born in municipalities showing the highest triatomine infestation rates in recent decades, 81.8% were able to recognize the vector insect (p = 0.0042; OR = 5.9), and 83.3% reported either themselves or someone in their families to have CD (p = 0.043, OR = 5.2). Of the 54 patients submitted to serological analysis, only 01 patient (1.9%) was positive for anti-T. cruzi antibodies, a 55 year old man from the rural area of Canguçu county. This study provides support for the evaluation to be extended to other cardiology centers, given the importance of Chagas disease in Brazil.