{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T06:35:42Z","timestamp":1771655742684,"version":"3.50.1"},"reference-count":40,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,9,16]],"date-time":"2021-09-16T00:00:00Z","timestamp":1631750400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001807","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de S\u00e3o Paulo","doi-asserted-by":"publisher","award":["Grant 2016\/25403-9"],"award-info":[{"award-number":["Grant 2016\/25403-9"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001807","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de S\u00e3o Paulo","doi-asserted-by":"publisher","award":["Grant 2018\/22093-4"],"award-info":[{"award-number":["Grant 2018\/22093-4"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cardiovasc. Med."],"abstract":"<jats:p><jats:bold>Background:<\/jats:bold> Chronic Chagas disease (CChD), one of the infectious parasitic diseases with the greatest social and economic impact upon a large part of the American continent, has distinct clinical manifestations in humans (cardiac, digestive, or mixed clinical forms). The mechanisms underlying the development of the most common and ominous clinical form, the chronic Chagas cardiomyopathy (CCC) have not been completely elucidated, despite the fact that a high intensity of parasite persistence in the myocardium is deemed responsible for an untoward evolution of the disease. The present study aimed to assess the parasite load CCC and its relation to left ventricular ejection fraction (LVEF), a definite prognostic marker in patients with CCC.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> Patients with CCC were clinically evaluated using 12-lead-electrocardiogram, echocardiogram, chest X-ray. Peripheral blood sampling (5 ml of venous blood in guanidine\/EDTA) was collected from each patient for subsequent DNA extraction and the quantification of the parasite load using real-time PCR.<\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> One-hundred and eighty-one patients with CCC were evaluated. A total of 140 (77.3%) had preserved left ventricular ejection fraction (of \u226540%), and 41 individuals had LV dysfunction (LVEF of &amp;lt;40%). A wide variation in parasite load was observed with a, mean of 1.3460 \u00b1 2.0593 (0.01 to 12.3830) par. Eq.\/mL. The mean \u00b1 SD of the parasite load was 0.6768 \u00b1 0.9874 par. Eq.\/mL and 3.6312 \u00b1 2.9414 par. Eq.\/mL in the patients with LVEF \u2265 40% and &amp;lt;40%, respectively.<\/jats:p><jats:p><jats:bold>Conclusion:<\/jats:bold> The blood parasite load is highly variable and seems to be directly related to the reduction of LVEF, an important prognostic factor in CCC patients.<\/jats:p>","DOI":"10.3389\/fcvm.2021.741347","type":"journal-article","created":{"date-parts":[[2021,9,16]],"date-time":"2021-09-16T04:40:56Z","timestamp":1631767256000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["Parasitic Load Correlates With Left Ventricular Dysfunction in Patients With Chronic Chagas Cardiomyopathy"],"prefix":"10.3389","volume":"8","author":[{"given":"Maykon Tavares","family":"de Oliveira","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andr\u00e9","family":"Schmidt","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria Cl\u00e1udia","family":"da Silva","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eduardo Ant\u00f4nio","family":"Donadi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jo\u00e3o Santana","family":"da Silva","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9 Ant\u00f4nio","family":"Marin-Neto","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2021,9,16]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"159","DOI":"10.1590\/S0074-02761909000200008","article-title":"Nova tripanozomiase humana. Estudos sobre a morfolojia e o ciclo evolutivo do Schizotrypanum cruzi n. gen., n. sp., ajente etil\u00f3gico de nova entidade morbida do homem","volume":"1","author":"Chagas","year":"1909","journal-title":"Mem Inst Oswaldo Cruz."},{"key":"B2","article-title":"Fact Sheet N\u00b0340","year":"2018"},{"key":"B3","doi-asserted-by":"publisher","first-page":"247","DOI":"10.1016\/j.idc.2004.01.005","article-title":"The discovery of Chagas disease: progress and prejudice","volume":"18","author":"Miles","year":"2004","journal-title":"Infect Dis Clin North Am"},{"key":"B4","doi-asserted-by":"publisher","first-page":"312","DOI":"10.1006\/expr.1998.4289","article-title":"Biological characterization of Trypanosoma cruzi stocks from Chilean insect vectors","volume":"89","author":"Solari","year":"1998","journal-title":"Exp Parasitol"},{"key":"B5","doi-asserted-by":"publisher","first-page":"201","DOI":"10.1590\/S0102-311X1993000200012","article-title":"[Chagas' disease and its control in Latin America: an analysis of possibilities]","volume":"9","author":"Dias","year":"1993","journal-title":"Cad Saude Publ"},{"key":"B6","doi-asserted-by":"publisher","first-page":"286","DOI":"10.1590\/S0037-86822012000300002","article-title":"Chagas disease. What is known and what should be improved: a systemic review","volume":"45","author":"Coura","year":"2012","journal-title":"Rev Soc Bras Med Trop"},{"key":"B7","first-page":"481","article-title":"Megacolon chag\u00e1sico.","volume-title":"Cl\u00ednica das Doen\u00e7as Intestinais","author":"Rezende","year":"1997"},{"key":"B8","doi-asserted-by":"publisher","first-page":"1388","DOI":"10.1016\/S0140-6736(10)60061-X","article-title":"Chagas disease","volume":"375","author":"Rassi","year":"2010","journal-title":"Lancet"},{"key":"B9","doi-asserted-by":"publisher","first-page":"1383","DOI":"10.1093\/europace\/eut092","article-title":"Another disappointing result with implantable cardioverter-defibrillator therapy in patients with Chagas disease","volume":"15","author":"Rassi","year":"2013","journal-title":"Europace"},{"key":"B10","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/978-3-030-44054-1_1","article-title":"Chagas disease: an unknown and neglected disease.","volume-title":"Chagas Disease","author":"de Oliveira","year":"2020"},{"key":"B11","doi-asserted-by":"crossref","DOI":"10.1007\/978-3-030-44054-1","volume-title":"Chagas Disease: A Neglected Tropical Disease","author":"Delgado","year":"2020"},{"key":"B12","doi-asserted-by":"publisher","first-page":"377","DOI":"10.1111\/pim.12107","article-title":"Immunoregulatory networks in human Chagas disease","volume":"36","author":"Dutra","year":"2014","journal-title":"Parasite Immunol"},{"key":"B13","doi-asserted-by":"publisher","first-page":"43","DOI":"10.1590\/S0102-311X2000000800005","article-title":"Epidemiological surveillance of Chagas disease","volume":"16","author":"Dias","year":"2000","journal-title":"Cad Sa\u00fade Publ."},{"key":"B14","doi-asserted-by":"publisher","first-page":"1109","DOI":"10.1161\/CIRCULATIONAHA.106.624296","article-title":"Pathogenesis of chronic Chagas heart disease","volume":"115","author":"Marin-Neto","year":"2007","journal-title":"Circulation"},{"key":"B15","doi-asserted-by":"publisher","first-page":"224","DOI":"10.1590\/0074-02760160334","article-title":"Chronic Chagas cardiomyopathy: a review of the main pathogenic mechanisms and the efficacy of aetiological treatment following the BENznidazole Evaluation for Interrupting Trypanosomiasis (BENEFIT) trial","volume":"112","author":"Rassi","year":"2017","journal-title":"Mem Inst Oswaldo Cruz"},{"key":"B16","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.echo.2014.10.003","article-title":"Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging","volume":"28","author":"Lang","year":"2015","journal-title":"J Am Soc Echocardiogr"},{"key":"B17","doi-asserted-by":"publisher","first-page":"286","DOI":"10.1016\/j.echo.2018.09.006","article-title":"Effects of trypanocidal treatment on echocardiographic parameters in Chagas cardiomyopathy and prognostic value of wall motion score index: a BENEFIT trial echocardiographic substudy","volume":"32","author":"Schmidt","year":"2019","journal-title":"J Am Soc Echocardiogr"},{"key":"B18","doi-asserted-by":"publisher","first-page":"11","DOI":"10.1016\/0166-6851(91)90116-N","article-title":"Polymerase chain reaction amplification of Trypanosoma cruzi kinetoplast minicircle DNA isolated from whole blood lysates: diagnosis of chronic Chagas' disease","volume":"48","author":"Avila","year":"1991","journal-title":"Mol Biochem Parasitol"},{"key":"B19","doi-asserted-by":"publisher","first-page":"171","DOI":"10.1590\/S0074-02761993000100030","article-title":"A simple protocol for the physical cleavage of Trypanosoma cruzi kinetoplast DNA present in blood samples and its use in polymerase chain reaction (PCR)-based diagnosis of chronic Chagas disease","volume":"88","author":"Britto","year":"1993","journal-title":"Mem Inst Oswaldo Cruz"},{"key":"B20","doi-asserted-by":"publisher","first-page":"53","DOI":"10.1016\/S0166-6851(03)00093-8","article-title":"Rapid quantitation of Trypanosoma cruzi in host tissue by real-time PCR","volume":"129","author":"Cummings","year":"2003","journal-title":"Mol Biochem Parasitol"},{"key":"B21","doi-asserted-by":"publisher","first-page":"e931","DOI":"10.1371\/journal.pntd.0000931","article-title":"International study to evaluate PCR methods for detection of Trypanosoma cruzi DNA in blood samples from Chagas disease patients","volume":"5","author":"Schijman","year":"2011","journal-title":"PLoS Negl Trop Dis"},{"key":"B22","doi-asserted-by":"publisher","first-page":"195","DOI":"10.1016\/j.actatropica.2007.05.019","article-title":"Development of a real-time PCR assay for Trypanosoma cruzi detection in blood samples","volume":"103","author":"Piron","year":"2007","journal-title":"Acta Trop"},{"key":"B23","doi-asserted-by":"publisher","first-page":"122","DOI":"10.1590\/S0074-02762009000900018","article-title":"Usefulness of PCR-based assays to assess drug efficacy in Chagas disease chemotherapy: value and limitations","volume":"104","author":"Britto","year":"2009","journal-title":"Mem Inst Oswaldo Cruz"},{"key":"B24","doi-asserted-by":"publisher","first-page":"e0003765","DOI":"10.1371\/journal.pntd.0003765","article-title":"Multiplex real-time PCR assay using TaqMan probes for the identification of Trypanosoma cruzi DTUs in biological and clinical samples","volume":"9","author":"Cura","year":"2015","journal-title":"PLoS Negl Trop Dis"},{"key":"B25","doi-asserted-by":"publisher","first-page":"240","DOI":"10.1016\/j.meegid.2011.12.009","article-title":"The revised Trypanosoma cruzi subspecific nomenclature: rationale, epidemiological relevance and research applications","volume":"12","author":"Zingales","year":"2012","journal-title":"Infect Genet Evol"},{"key":"B26","doi-asserted-by":"publisher","first-page":"23","DOI":"10.1016\/j.actatropica.2012.08.020","article-title":"Towards the establishment of a consensus real-time qPCR to monitor Trypanosoma cruzi parasitemia in patients with chronic Chagas disease cardiomyopathy: a substudy from the BENEFIT trial","volume":"125","author":"Moreira","year":"2013","journal-title":"Acta Trop."},{"key":"B27","doi-asserted-by":"publisher","first-page":"1899","DOI":"10.1056\/NEJMoa1313122","article-title":"Randomized trial of posaconazole and benznidazole for chronic Chagas' disease","volume":"370","author":"Moreira","year":"2014","journal-title":"N Engl J Med."},{"key":"B28","doi-asserted-by":"publisher","first-page":"82","DOI":"10.1007\/978-0-387-78267-6_6","article-title":"Trypanosoma cruzi: parasite and host cell signaling during the invasion process","volume":"47","author":"Yoshida","year":"2008","journal-title":"Subcell Biochem"},{"key":"B29","doi-asserted-by":"publisher","first-page":"620","DOI":"10.1186\/s13071-016-1907-5","article-title":"Untangling the transmission dynamics of primary and secondary vectors of Trypanosoma cruzi in Colombia: parasite infection, feeding sources and discrete typing units","volume":"9","author":"Hern\u00e1ndez","year":"2016","journal-title":"Parasit Vectors"},{"key":"B30","doi-asserted-by":"publisher","first-page":"e0208133","DOI":"10.1371\/journal.pone.0208133","article-title":"Monitoring the parasite load in chronic Chagas disease patients: comparison between blood culture and quantitative real time PCR","volume":"13","author":"D'\u00c1vila","year":"2018","journal-title":"PLoS One"},{"key":"B31","doi-asserted-by":"publisher","first-page":"e2000","DOI":"10.1371\/journal.pntd.0002000","article-title":"Analytical performance of a multiplex Real-Time PCR assay using TaqMan probes for quantification of Trypanosoma cruzi satellite DNA in blood samples","volume":"7","author":"Duffy","year":"2013","journal-title":"PLoS Negl Trop Dis."},{"key":"B32","doi-asserted-by":"publisher","first-page":"1249","DOI":"10.1111\/trf.12989","article-title":"Evidence of meaningful levels of Trypanosoma cruzi in platelet concentrates from seropositive blood donors","volume":"55","author":"Cancino-Faure","year":"2015","journal-title":"Transfusion."},{"key":"B33","doi-asserted-by":"publisher","first-page":"e0006939","DOI":"10.1371\/journal.pntd.0006939","article-title":"Exploring the parasite load and molecular diversity of Trypanosoma cruzi in patients with chronic Chagas disease from different regions of Brazil","volume":"12","author":"Rodrigues-Dos-Santos","year":"2018","journal-title":"PLoS Negl Trop Dis"},{"key":"B34","doi-asserted-by":"publisher","first-page":"e0008311","DOI":"10.1371\/journal.pntd.0008311","article-title":"Quantification of parasite burden of Trypanosoma cruzi and identification of Discrete Typing Units (DTUs) in blood samples of Latin American immigrants residing in Barcelona, Spain","volume":"14","author":"Tavares de Oliveira","year":"2020","journal-title":"PLoS Negl Trop Dis"},{"key":"B35","doi-asserted-by":"publisher","first-page":"1534","DOI":"10.1111\/tmi.13487","article-title":"Circulating Trypanosoma cruzi load and major cardiovascular outcomes in patients with chronic Chagas cardiomyopathy: a prospective cohort study","volume":"25","author":"Echeverr\u00eda","year":"2020","journal-title":"Trop Med Int Health"},{"key":"B36","doi-asserted-by":"publisher","first-page":"757","DOI":"10.1590\/S1516-31801995000200005","article-title":"Autoimmunity in Chagas' heart disease","volume":"113","author":"Cunha-Neto","year":"1995","journal-title":"S\u00e3o Paulo Med J"},{"key":"B37","doi-asserted-by":"publisher","first-page":"555","DOI":"10.1016\/S0020-7519(01)00163-1","article-title":"Autoimmunity in Chagas heart disease","volume":"31","author":"Leon","year":"2001","journal-title":"Int J Parasitol."},{"key":"B38","doi-asserted-by":"publisher","first-page":"918","DOI":"10.1093\/cid\/civ446","article-title":"Sustained domestic vector exposure is associated with increased chagas cardiomyopathy risk but decreased Parasitemia and congenital transmission risk among young women in Bolivia","volume":"61","author":"Kaplinski","year":"2015","journal-title":"Clin Infect Dis."},{"key":"B39","doi-asserted-by":"publisher","first-page":"287","DOI":"10.1097\/QCO.0b013e3282f88b80","article-title":"Current concepts in immunoregulation and pathology of human Chagas disease","volume":"21","author":"Dutra","year":"2008","journal-title":"Curr Opin Infect Dis."},{"key":"B40","doi-asserted-by":"publisher","first-page":"E29","DOI":"10.1111\/j.1399-0012.2009.01202.x","article-title":"Transplantation for Chagas' disease: an overview of immunosuppression and reactivation in the last two decades","volume":"24","author":"Bacal","year":"2010","journal-title":"Clin Transplant"}],"container-title":["Frontiers in Cardiovascular Medicine"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcvm.2021.741347\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,9,16]],"date-time":"2021-09-16T04:41:00Z","timestamp":1631767260000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcvm.2021.741347\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,9,16]]},"references-count":40,"alternative-id":["10.3389\/fcvm.2021.741347"],"URL":"https:\/\/doi.org\/10.3389\/fcvm.2021.741347","relation":{},"ISSN":["2297-055X"],"issn-type":[{"value":"2297-055X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,9,16]]},"article-number":"741347"}}