Abstract & Commentary
Chagas Disease as a Cause of Dilated Cardiomyopathy in New York City
By Dean L. Winslow, MD, FACP, FIDSA,
Clinical Professor of Medicine and Pediatrics Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Associate Editor of Infectious Disease Alert
Dr. Winslow is a consultant for Siemens Diagnostic.
SYNOPSIS: In a sample of New York City immigrants with dilated cardiomyopathy the point prevalence of infection with Trypanosoma cruzi was found to be 13%.
SOURCE: Kapelusznik L, et al. Chagas disease in Latin American immigrants with dilated cardiomyopathy in New York City. CID 2013; ePub Mar 28, 2014.
A point prevalence study was conducted at the Cardiology clinics of Mount Sinai Medical Center and Elmhurst Hospital Center between 2009-2011. All patients were eligible for inclusion if they were >= 18 years old, did not have evidence of ischemic cardiomyopathy (CM), had left ventricular ejection fraction (LVEF) < 45% and lived for >= 12 months in a Chagas disease (CD) endemic country. Serum samples from patients were sent to the Centers for Disease Control and Prevention for T. cruzi IgG testing. Samples were considered positive if both EIA and IFA tests were positive. If these assays were discordant/indeterminate if an immunoblot assay using trypomastigote excreted-secreted antigens (TESA) were positive, then the individual was judged to be infected.
Forty-four eligible persons were identified and 39 agreed to participate in the study. Mean age of patients was 62 years. Of the 39 patients, 5 (13%) were infected with T. cruzi and none had prior knowledge of infection. Premature ventricular contractions (VPC’s) were more commonly seen on routine 12 lead EKG’s in Chagas disease patients than in the uninfected participants but right bundle branch block (RBBB) prevalence was not significantly different between the two groups.
COMMENTARY
This study confirms the high point prevalence of CD as a cause of CM in patients from CD-endemic areas. A similar study conducted in Los Angeles in immigrants with CM primarily from Mexico and El Salvador found a CD infection rate of 15%.1
It is clear that CD is a common and often overlooked cause of dilated CM in the U.S. While antiparasitic treatment probably has little utility in patients who already chronic dilated CM, it has been shown that patients with CD as a cause of CM have longer survival following cardiac transplantation than patients with idiopathic dilated CM,2 suggesting that these patients should be considered favorably for transplantation.
It is also now apparent that Chagas disease is endemic in Texas. At a recent meeting we had earlier this year in San Antonio where we brought together a wonderful multidisciplinary team of dedicated USAF, US Army, and Texas Department of Public Health professionals I was made aware of the potential threat of CD in Texas. Dr. Thomas (Leo) Cropper and Dr. Bryant Webber (both USAF Public Health officers) are in the process of studying the potential threat of CD to military trainees in the San Antonio area. Chagas disease (including acute Chagasic myocarditis) has been demonstrated in military working dogs, U.S. Customs and Border Protection working dogs and in civilian veterinary practices in Texas (personal communication, Dr. E. Wozniak). This is of significance since early CD in dogs and humans can be effectively treated with antiparasitic agents. It has also been demonstrated that a high percentage of meso-mammal hosts (including white-tail deer, raccoons, striped skunks, opossums, and wood rats, etc.) in Texas are infected with T.cruzi (personal communication, Dr. M. Kramm) and the triatomine vectors show high rates of infection (personal communication, Dr. W. Roachell). Most importantly, several cases of autochthonous transmission to humans of CD have occurred in Texas (personal communication, Dr. C. Tully).
Chagas disease is clearly an under-recognized cause of cardiac disease in the U.S. While we eagerly await the results of the excellent science being done now in Texas by the U.S. military, Texas Department of Public Health and various academic institutions in Texas, I believe it is time that infectious diseases specialists, cardiologists, internists and family practitioners throughout the U.S. should start looking routinely for T.cruzi infection in patients from endemic areas (to include the Southern U.S. in addition to Latin America) who present with either dilated cardiomyopathy or acute myocarditis.
References
- Traina M, et al. Prevalence of Chagas disease in U.S. Latin American immigrant population with cardiomyopathy. 58th Annual Meeting of the ASTMH. November 2009, Washington, DC.
- Bocchi EA, et al. The paradox of survival results after heart transplantation for cardiomyopathy caused by Trypanosoma cruzi. Guidelines Group for Heart Transplantation of the Brazilian Society of Cardiology. Ann Thorac Surg 2001; 71: 1833-8.
