There are no electrocardiographic changes considered pathognomonic of chronic Chagas cardiomyopathy. The main findings are related to the disease's predilection for the cardiac conduction system, as well as to the myocardial fibrosis associated with incipient chronic myocarditis.

Electrocardiographic Changes

  • Varying degrees of AV block
  • Bundle branch blocks, far more commonly RBBB, with or without LAFB
  • Manifestations of sinus node dysfunction, such as sinus bradycardia, AF, and sinoatrial block
  • Low QRS voltage in the frontal plane leads
  • Electrically inactive areas may be present in up to 40% of cases
  • Ventricular arrhythmias

ECG in Chagas Disease

Electrocardiogram in Chagas disease

Chronic Chagas cardiomyopathy. Patient diagnosed with Chagas disease whose ECG shows right bundle branch block (RBBB) associated with left anterior fascicular block (LAFB). This combination of blocks is very common, though not pathognomonic, in this form of cardiomyopathy.

References

  1. Scheffer MK, De Marchi MFN, de Alencar Neto JN, Felicioni SP. Eletrocardiograma de A a Z. São Paulo: Manole, 2024.
  2. Dias JCP, Ramos AN, Gontijo ED, Luquetti A, et al. II Consenso Brasileiro em Doença de Chagas, 2015. Epidemiol Serv Saúde. 2016;25:7–86.
  3. Marin-Neto JA, Simões MV, Sarabanda ÁVL. Cardiopatia chagásica. Arq Bras Cardiol. 1999;72(3):247–63.