Teste ergométrico e o Holter de 24 horas na detecção de arritmias ventriculares complexas em diferentes estádios da cardiopatia chagásica crônica

Clinical, Epidemiological and Demographic Profile of Patients Undergoing Holter (24 h) at a Health Center in Belém do Pará: a Retrospective Study

Introduction: Dynamic electrocardiography by the Holter system can be divided into four major groups: evaluation of clinical manifestations related to the presence of altered heart rhythm; assessment of myocardial ischemia; risk assessment of future cardiac events; and therapeutic assessment. Objective: To identify the clinical, epidemiological and demographic profile that is associated with electrocardiographic changes in the 24-hour Holter in patients seen at the Escola do Marco Health Center in Belém do Pará, Brazil. Methods: We carried out a cross-sectional and retrospective study, with data from patients such as: clinical and electrocardiographic correlation, indications, tachyarrhythmias, bradyarrhythmias, medications in use, provenance, demographic data and behavior modification. All of the information was compiled in a standardized protocol. Results: The main electrocardiographic findings were: supraventricular and ventricular extrasystoles less than 1% (reported in 71 and 57% of patients, respectively). Conclusion: The 24-hour Holter still has an important role in the identification of patients with electrocardiographic changes. The main indications for the examination were to assess the severity of arrhythmia (32%) and palpitation to clarify (23%), and there were uncommon findings, but of great clinical importance and with statistical significance, such as almost three times more frequent nonsustained ventricular tachycardia in patients with heart failure, cardiac, symptomatic frequent extrasystole (> 3%), more frequent atrial fibrillation in the elderly and men (60%) and with underuse of anticoagulant therapy (20%) due to non-diagnosis prior to the exam, and changes in the ST segment with a tendency in patients with systemic arterial.

Exercise tests in Chagas cardiomyopathy: an overview of functional evaluation, prognostic significance, and current challenges

Patients with Chagas cardiomyopathy (ChC) usually progress with fatigue and dyspnea. Exercise tests are valuable for the functional evaluation of these patients. However, information about the applicability of the exercise tests is scattered, and no studies have systematically reviewed the results. Thus, the present review explored the general aspects and prognostic value of exercise tests in patients with ChC. A literature search of the MEDLINE, Web of Science, CINAHL, Scopus, and LILACS databases was performed to identify relevant studies. There were no data restrictions, and articles that met the objective of the study were selected. Articles written in English, Portuguese, and Spanish were considered, and 25 articles were finally included. The peak oxygen uptake (VO2peak) was correlated with demographic and echocardiographic variables. Echocardiographic features of the left ventricular diastolic function and right ventricular systolic function appeared to be determinants of functional capacity, in addition to age and sex. VO2peak was associated with higher mortality, especially in patients with dilated ChC. The minute ventilation/carbon dioxide production slope (VE/VCO2 slope) was a strong predictor of survival; however, more studies are needed to verify this observation. Field tests showed moderate to strong correlation with VO2peak and thus may be inexpensive tools for the functional evaluation of patients with ChC. However, few studies have verified their prognostic significance. While exercise tests are useful tools for functional assessment, information is scarce regarding further considerations, and many of the criteria are based on guidelines for other heart diseases.

Chagas Cardiomyopathy: An Update of Current Clinical Knowledge and Management: A Scientific Statement From the American Heart Association

Background:

Chagas disease, resulting from the protozoan Trypanosoma cruzi , is an important cause of heart failure, stroke, arrhythmia, and sudden death. Traditionally regarded as a tropical disease found only in Central America and South America, Chagas disease now affects at least 300 000 residents of the United States and is growing in prevalence in other traditionally nonendemic areas. Healthcare providers and health systems outside of Latin America need to be equipped to recognize, diagnose, and treat Chagas disease and to prevent further disease transmission.

Methods and Results:

The American Heart Association and the Inter-American Society of Cardiology commissioned this statement to increase global awareness among providers who may encounter patients with Chagas disease outside of traditionally endemic environments. In this document, we summarize the most updated information on diagnosis, screening, and treatment of T cruzi infection, focusing primarily on its cardiovascular aspects. This document also provides quick reference tables, highlighting salient considerations for a patient with suspected or confirmed Chagas disease.

Conclusions:

This statement provides a broad summary of current knowledge and practice in the diagnosis and management of Chagas cardiomyopathy. It is our intent that this document will serve to increase the recognition of Chagas cardiomyopathy in low-prevalence areas and to improve care for patients with Chagas heart disease around the world.

Prognostic value of exercise-induced ventricular arrhythmia in Chagas' heart disease

OBJECTIVE

To determine the prevalence and the prognostic value of exercise-induced ventricular arrhythmia (EIVA) in chronic Chagas' heart disease.

STUDY DESIGN AND SETTING

An open prospective cohort of 130 clinically stable patients at a University Hospital outpatient unit in Rio de Janeiro, Brazil, was followed up at scheduled clinical visits from 1990 through 2007. The endpoint was total cardiovascular mortality. Survival curves (Kaplan-Meier) and a multivariate Cox proportional hazard model were adjusted to determine the association between EIVA and mortality.

RESULTS

The median duration of follow-up was 9.9 years (range, 132 days to 17 years). EIVA prevalence was 43.1% (95% CI: 34.5-51.7). Thirty-three cardiovascular deaths (25.4%) occurred. The hazard ratio of EIVA for cardiovascular death, after adjustment for age, was 1.84 (P = 0.09). An interaction was found between EIVA and cardiomegaly on x-ray. In the group with cardiomegaly, the hazard of dying was four times greater in the presence of EIVA (P for interaction = 0.05).

CONCLUSION

In clinically stable chagasic subjects with cardiomegaly, EIVA is a clinically significant marker of total cardiovascular mortality and may be a useful risk stratification tool in this population.

[Association between left ventricular wall motion abnormalities and ventricular arrhythmia in the indeterminate form of Chagas disease]

INTRODUCTION

Chagas' disease can lead to severe and potentially lethal damage of cardiac function. Thus, the identification of cardiac abnormalities in patients presenting the indeterminate form (IF) can be important for risk stratification. This paper aimed to demonstrate whether IF chagasic patients who presented wall motion abnormalities showed functional and electric disturbances compared to patients with normal echocardiogram and Doppler studies.

METHODS

Thirty eight patients with the IF were studied, including 26 chagasic patients with normal electrocardiographic, radiological and echocardiographic exams and 12 chagasic patients showing segmental wall motion abnormalities in the echocardiographic exam. All the patients were submitted to complete echocardiogram and Doppler study, including tissue Doppler imaging (TDI) and Holter 24h monitoring.

RESULTS

Among the variables evaluated, significant differences among the two groups were verified in relation to: the ejection fraction (p ≤ 0.001); left ventricular systolic dimension (p = 0.029); isovolumic contraction time, measured by TDI in the basal segments of the left ventricle (p < 0.05); and the presence of isolated (p = 0.0005) and paired ventricular extrasystoles (p = 0.003), in the Holter monitoring.

CONCLUSIONS

The indeterminate form of Chagas' disease can present cardiac wall motion abnormality, demonstrating functional and electric damage compared to chagasic patients with normal echocardiogram.