Electrocardiographic Abnormalities in Elderly Chagas Disease Patients: 10‐Year Follow‐Up of the Bambuí Cohort Study of Aging

Abstract

BackgroundElectrocardiography has been considered an important tool in the management of Chagas disease (ChD) patients, although its value in elderly infected patients is unknown. This study was designed to investigate the prevalence and prognostic value of electrocardiographic abnormalities in Trypanosoma cruzi infected and noninfected older adults.Methods and ResultsWe studied 1462 participants in Bambuí City, Brazil, with electrocardiogram (ECG) records classified by the Minnesota Code. Follow‐up time was 10 years; the endpoint was mortality. Adjustment for potential confounding variables included age, gender, conventional risk factors, and B‐type natriuretic peptide (BNP). The mean age was 69 years (60.9% women). The prevalence of ChD was 38.1% (n=557). ECG abnormalities were more frequent in ChD patients (87.6% versus 77.7%, P<0.001). Right bundle branch block (RBBB) with left anterior hemiblock (LAH) was strongly related to ChD (OR: 11.99 [5.60 to 25.69]). During the mean follow‐up time of 8.7 years, 556 participants died (253 with ChD), and only 89 were lost to follow‐up. ECG variables of independent prognostic value for death in ChD included absence of sinus rhythm, frequent ventricular and supraventricular premature beats, atrial fibrillation, RBBB, old and possible old myocardial infarction, and left ventricular hypertrophy. The presence of any major ECG abnormalities doubled the risk of death in ChD patients (HR: 2.18 [1.35 to 3.53]), but it also increased the risk in non‐ChD subjects (HR: 1.50 [1.07 to 2.10]); the risk of death increased with the number of major abnormalities in the same patient.ConclusionECG abnormalities are more common among elderly Chagas disease patients and strongly predict adverse outcomes.

Electrocardiographic and Echocardiographic Abnormalities in Chagas Disease: Findings in Residents of Rural Bolivian Communities Hyperendemic for Chagas Disease

“…A Brazilian study from the 1980s found the highest rate of ECG abnormalities in participants 25-44 years old, and interpreted this finding as suggestive of excess mortality due to Chagas cardiomyopathy among older residents [21]. However, more recent studies show steadily increasing prevalence of abnormalities with age, perhaps due to better survival of affected individuals in recent decades [22, 23, 24]. While we found the highest rates of bundle branch blocks and 1 st degree AVB in the oldest age group, 3 rd degree AVBs were found only among participants younger than 50, possibly reflecting premature mortality among those who had high grade AVBs for longer periods of time.…”

“…We may have therefore excluded some individuals with changes due to T. cruzi infection. However, in recent publications from Brazil, low QRS voltage and ST-T wave changes were equally frequent among T. cruzi -infected and uninfected adults [24, 25]. Especially in the absence of a seronegative comparator group, we considered specificity more important than sensitivity.…”

Altered Cardiomyocyte Function and Trypanosoma cruzi Persistence in Chagas Disease

“…2 Clinical studies have described impaired electromechanical properties in chagasic hearts. 3,28,29 A number of hypotheses were proposed to better explain the clinical phenotype observed in chagasic patients. Two of them are generally accepted based on the relationship between parasite and host.…”

Biomarkers and Mortality in Severe Chagas Cardiomyopathy

“…Furthermore, individuals with Chagas cardiomyopathy, even in the absence of systolic dysfunction, had higher BNP levels than healthy controls (26). For those with heart failure due to Chagas cardiomyopathy, BNP has previously been shown to be a strong predictor of mortality (27) (26) (28) (31). NT-pro BNP levels are correlated with severity of LV dysfunction in Chagas disease (32).…”