Search

Background: Chagas heart disease (CHD) is characterized by progressive myocardial inflammation associated with myocardial fibrosis and segmental abnormalities that may lead to malignant ventricular arrhythmia and sudden cardiac death. This arrhythmia might be related to the persistence of parasitemia or inflammation in the myocardium in late-stage CHD. Positron emission tomography/computed tomography (PET/CT) has been used to detect myocardial inflammation in non-ischemic cardiomyopathies, such as sarcoidosis, and might be useful for risk prediction in patients with CHD., Methods and Results: Twenty-four outpatients with chronic CHD were enrolled in this prospective cross-sectional study between May 2019 and March 2022. The patients were divided into two groups: those with sustained ventricular tachycardia and/or aborted sudden cardiac death who required implantable cardioverter-defibrillators, and those with the same stages of CHD and no complex ventricular arrhythmia. Patients underwent 18 F-fluorodeoxyglucose ( 18 F-FDG) and 68 Ga-DOTATOC PET/CT, and blood samples were collected for qualitative parasite assessment by polymerase chain reaction. Although similar proportions of patients with and without complex ventricular arrhythmia showed 18 F-FDG and 68 Ga-DOTATOC uptake, 68 Ga-DOTATOC corrected SUV max was higher in patients with complex arrhythmia (3.4 vs 1.7; P = .046), suggesting that inflammation could be associated with the presence of malignant arrhythmia in the late stages of CHD. We also detected Trypanosoma cruzi in both groups, with a nonsignificant trend of increased parasitemia in the group with malignant arrhythmia (66.7% vs 33.3%)., Conclusion: 18 F-FDG and 68 Ga-DOTATOC uptake on PET/CT may be useful for the detection of myocardial inflammation in patients with Chagas cardiomyopathy, and 68 Ga-DOTATOC uptake may be associated with the presence of malignant arrhythmia, with potential therapeutic implications., (© 2023. The Author(s) under exclusive licence to American Society of Nuclear Cardiology.)

Background: Sudden cardiac death (SCD) can be the first clinical event of Chagas heart disease (CHD). However, current guidelines contain no clear recommendation for early cardioverter-defibrillator implantation. Using imaging modalities, we evaluated associations among autonomic denervation, myocardial hypoperfusion, fibrosis and ventricular arrhythmia in CHD., Methods and Results: Twenty-nine patients with CHD and preserved left ventricular function underwent 123I-metaiodobenzylguanidine (MIBG) scintigraphy, 99mTc-methoxyisobutylisonitrile (MIBI) myocardial perfusion and cardiac magnetic resonance imaging (MRI). They were divided into arrhythmic (≥ 6 ventricular premature complexes/h and/or non-sustained ventricular tachycardia on 24-hour Holter, n = 15) and non-arrhythmic (< 6 ventricular premature complexes/h and no ventricular tachycardia; n = 14) groups. The arrhythmic group had higher denervation scores from MIBG imaging (23.2 ± 18.7 vs 5.6 ± 4.9; P < .01), hypoperfusion scores from MIBI SPECT (4.7 ± 6.8 vs 0.29 ± 0.6: P = .02), innervation/perfusion mismatch scores (18.5 ± 17.5 vs 5.4 ± 4.8; P = .01) and fibrosis by late gadolinium enhancement on MRI (14.3% ± 13.5% vs 4.0% ± 2.9%; P = .04) than the non-arrhythmic group., Conclusion: These imaging parameters were associated with ventricular arrhythmia in early CHD and may enable risk stratification and the implementation of primary preventive strategies for SCD., (© 2023. The Author(s) under exclusive licence to American Society of Nuclear Cardiology.)