RESUMEN
Background: Chagas cardiomyopathy (CC) increases cardiovascular mortality associated with congestive heart failure (CHF), ventricular arrhythmias (VA), and sudden cardiac death (SCD). Different imaging techniques have been tested to assess disease progression and cardiac risk in individuals with Chagas disease (ChD). In this systematic review, we evaluated the accuracy in detecting cardiac complications in CC patients using cardiac magnetic resonance (CMR) and speckle tracking echocardiography (STE). Methods: A search was done on PubMed, Cochrane, and Embase for studies in humans over 18 years of age with ChD. Demographic data, research methodology, imaging parameters, and cardiac outcomes were extracted, and study quality was assessed, resulting in a narrative description. Results: Twelve studies with 1124 patients were analyzed. One study discovered a contractility pattern by STE. Four studies assessed the identification of Early Cardiac Impairment (ECI) and VA risk, respectively, while three studies evaluated the risk of SCD. Global Longitudinal Strain (GLS) identified patients with ECI (-18.5 ± 3.4% non-fibrosis vs -14.0 ± 5.8% fibrosis, p = 0.006 and -18 ± 2% non-fibrosis vs -15 ± 2% fibrosis, p = 0.004). The amount of fibrosis > 11.78% or in two or more contiguous transmural segments were markers for VA risk. GLS and the amount of fibrosis were found to be predictors of SCD. Conclusions: STE may be considered a screening technique for identifying the subclinical status of CHF. CMR using Late Gadolinium Enhancement (LGE) is considered a relevant parameter for stratifying patients with ChD who are at risk of SCD. Fibrosis and GLS can be used as markers to categorize patients at risk for arrhythmias.
RESUMEN
OBJECTIVES: Cardiovascular magnetic resonance (CMR) provides information on myocardial ischemia through stress perfusion studies. In clinical practice, the grading of induced perfusion defects is performed by visual estimation of their extension. The aim of our study is to devise a score of the degree of ischemia and to test its prognostic value. METHODS: Between 2009 and 2011, patients with diagnosed or suspected coronary artery disease underwent stress perfusion CMR. A score of ischemic burden was calculated on the basis of (1) stress-induced perfusion defect, (2) persistence, (3) transmurality, and (4) stress-induced contractile defect. Follow-up was censored after 4 years and primary end-point was defined by a composite of death, heart failure episode, acute coronary syndrome, and ventricular arrhythmias. Univariate and multivariate logistic regressions were used to assess the strength of the association between the CMR ischemic variables, and the composite outcome. RESULTS: Forty-four of the 128 patients (34%) presented with adverse events, while 84 (66%) did not. Sixty-one patients (48%) had negative perfusion studies while 67 (52%) showed perfusion defect. Patients with positive perfusion studies and adverse events (n = 39) had higher number of segments with persistent defect (3.3 vs 1.3, p = 0.001) and highest score (19.6 vs 13.3 p = 0.012) than patients with positive perfusion studies and absence of events (n = 28). The number of segments with persistent defect showed the strongest predictive value of adverse events (OR 1.54; CI 1.19-2.00; p < 0.001). CONCLUSIONS: The score of ischemic burden proposed herein has prognostic value. Persistence of a perfusion defect has the strongest impact on prognosis. KEY POINTS: ⢠Cardiovascular magnetic resonance provides information on myocardial ischemia by visual estimation of the presence of perfusion defects induced by stress. ⢠There is not a standardized method for grading perfusion defects which, in practice, is performed by visual estimation of their extension. ⢠As proven in this study, the integration of several parameters of perfusion defects (in addition to extension) into a semiquantitative score has prognostic value.