Chagas cardiomyopathy and implantable cardioverter defibrillator implantation: similarities and differences with dilated cardiomyopathy

Abstract

Chagas' disease causes more deaths in the United States than any other parasitic disease.1 In endemic countries (most of Latin America), vectorial transmission of the disease occurs through haematophagous insects, which become vectors for Trypanosoma cruzi by biting an infected animal or person. In non-endemic countries (such as Europe and the United States), the disease is transmitted through blood transfusions, organ donations, and from mother to child at birth; however, the disease may also develop in individuals who had initially become infected in their native country, and then moved.2,3 The disease has three distinct phases. The initial infection is followed by a long ‘indeterminate phase’ (asymptomatic), in which parasites are sequestered in tissues; at some point, many years after infection, a substantial number of patients develop a phase of overt disease. In total, 20–30% of infected patients will suffer from chronic chagasic cardiomyopathy. Chagas cardiomyopathy is the most serious manifestation of the chronic form of Chagas' disease, and it represents the most common type of chronic myocarditis in the world.4 Chagasic cardiomyopathy shares clinical features of ‘classical’ dilated cardiomyopathy, with LV dilatation, dyssynergic segments, aneurysm of the apex, and dilatation and dysfunction of right ventricle. Patients with chagasic cardiomyopathy have a prognosis similar to or worse than that of patients with dilated cardiomyopathy: they die of progressive heart failure, pulmonary embolism, or sudden death. Indeed, life-threatening arrhythmias occur (and recur) quite often, in spite of antiarrhythmic therapy.5 Thus, deciding whether to implant an implantable cardioverter defibrillator (ICD) would seem to represent a very important aspect of clinical management of these patients. However, thus far ICDs have been used only sporadically in this condition, even for secondary prevention of patients with previous episode of ventricular tachycardia (VT) … *Corresponding author. Tel: +39 075 527 1509, Fax: +39 075 527 1244. Email: giuseppe.ambrosio{at}ospedale.perugia.it