Implantable Cardioverter Defibrillators in Patients with Chagas' Disease: Are They Different from Patients with Coronary Disease?

Abstract

Chagas' disease is a parasitic affliction, endemic to certain regions of South America, which may lead to a chronic dilated nonischemic cardiomyopathy. Ten Chagasic patients were compared to 18 coronary patients undergoing transvenous ICD implantation for ventricular tachycardia (VT), ventricular fibrillation (VF), or aborted cardiac arrest. Indications for ICD implantation were either drug intolerance or refractoriness, or no inducible tachyarrhythmia at EPS. There were no statistically significant differences between the Chagas and coronary artery disease groups with respect to age (60.2 vs 62.6 yrs), NYHA Class II (50% vs 62%), ejection fraction (31.1% vs 29.7%), and incidence of cardiac arrest (20% vs 33%), respectively. The following ICD implant and long-term follow-up variables were compared between the two groups: pacing threshold (0.94 V vs 0.95 V), defibrillation threshold (19.5 J vs 19.6 J), number of VT episodes (414 vs 435), number of spontaneous VT terminations (86 vs 187), percent efficacy of antitachycardia pacing (93.9% vs 92.1%), and total number of shocks (112 vs 145). These differences were not statistically significant. We conclude that patients with Chagas' disease, compared with coronary artery disease patients, have similar clinical characteristics leading to ICD implantation. Furthermore, no differences were found with respect to ICD and long-term follow-up characteristics between the two groups.

ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death

“…Amiodarone appears to be effective in treating ventricular tachyarrhythmias, and death occurs as a result of either refractory HF or arrhythmias (485). Device therapy including the ICD is frequently used in the late phase (486). In those with good functional status (e.g., NYHA functional class I and II), SCD is a rare event when patients are treated with amiodarone.…”

I Diretriz Latino-Americana para o Diagnóstico e Tratamento da Cardiopatia Chagásica

“…Pre-and intraoperative electrophysiological mapping has allowed the identification of the site of origin and its relationship to akinesia and dyskinesia areas usually located in the left ventricle 227 . The analysis of biopsy specimens obtained during surgical treatment guided by electrophysiological mapping has confirmed the presence of the scar substrate 228 , showing that the inferior, lateral and basal LV walls were the most frequent sites of origin of SVT, independently of the presence of apical aneurysm 225 . With technological development, the surgical treatment of SVT in CCC has been gradually replaced by the treatment via catheter, being currently rarely recommended, except for highly selected patients (Table 9).…”

“…In addition, SVT can have multiple sites of origin, making the task of eliminating all circuits a challenge 201,207,213,229,230 . In general, the site of origin of well-tolerated recurring SVT can be identified and the SVT interrupted in 60%-80% of the patients, but rapid and poorly tolerated SVT are frequently induced in the final assessment of the procedure 201,213,[227][228][229] . During long-term follow-up, at least 50% of the patients undergoing conventional ablation have clinical relapse, justifying the maintenance of antiarrhythmic drugs or ICD implantation 230 .…”

Ventricular arrhythmias in Chagas disease

“…All of these studies investigated patients for whom ICD was indicated for the prevention of arrhythmias secondary to ChD. Studies by Muratore et al (50), (51) and Fonseca et al (53) found no difference between the populations with and without Chagas disease in the numbers of arrhythmia episodes, shocks, and deaths. In contrast, the studies by Martinelli-Filho et al (44) , Rabinovich et al (51) , Moreira (49) , Cardinalli-Neto et al (54) , Cardinalli-Neto et al (55) , Barbosa et al (52) and the ICD registry for patients with Chagas disease in Latin America, published in 2009 (56) , found differences between the chagasic and non-chagasic populations.…”

“…Studies of ICD implantation in patients with ChD have aimed to evaluate its effi cacy and safety and to identify predictors of appropriate therapy (47), (48) . In addition, several studies have compared the results of ICD implantation in ChD patients with the results of ICD implantation in the non-chagasic population to identify similarities and differences between these populations (44), (49)(50)(51)(52) . All of these studies investigated patients for whom ICD was indicated for the prevention of arrhythmias secondary to ChD.…”