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Electrophysiological characteristics of Chagas disease
Insights
Chagas disease patients often exhibit abnormal heart conduction and arrhythmias. Low ejection fraction significantly increases the risk of inducible ventricular arrhythmias in these patients.
Area of Science:
- Cardiology
- Infectious Diseases
- Electrophysiology
Background:
- Chagas disease is a growing global health concern due to migration.
- Electrophysiological studies are crucial for evaluating cardiac function in Chagas disease patients.
- Assessing sinus node function, atrioventricular conduction, and His-Purkinje system is vital.
Purpose of the Study:
- To characterize electrophysiological study findings in patients with Chagas disease.
- To correlate baseline characteristics with electrophysiological results.
- To identify risk factors for arrhythmias in Chagas disease.
Main Methods:
- Retrospective descriptive study of 115 Chagas disease patients.
- Electrophysiological studies were conducted over three years in Brazil.
- Data included baseline characteristics, ECG, echocardiogram, and Holter monitoring.
Main Results:
- Abnormalities in sinus node function (6.9%) and atrioventricular conduction (32.2%) were observed.
- Intraventricular conduction defects were present in 33.9% of patients.
- Nearly half (48%) had inducible ventricular arrhythmias, with lower ejection fraction (<40%) increasing risk (OR: 1.94).
Conclusions:
- Low ejection fraction is a significant risk factor for inducible ventricular arrhythmias in Chagas disease.
- Sinus node and conduction system abnormalities are common, affecting about one-third of patients.
- Complex ventricular arrhythmias on Holter monitoring did not predict inducible arrhythmias.
Objective:
Chagas disease has become a global problem due to changing migration patterns. An electrophysiological study is generally indicated for assessing sinus node function, conduction through the atrioventricular node and His-Purkinje system, in addition to evaluating the mechanisms of arrhythmia. The aim of this study was to describe the characteristics of electrophysiological study findings in patients with Chagas disease.
Methods:
A retrospective descriptive study of 115 consecutive patients with Chagas disease undergoing an electrophysiological study over the last three years in a tertiary hospital in Brazil. Baseline characteristics, electrocardiogram, echocardiogram, and 24-hour Holter monitoring findings were recorded and correlated with the electrophysiological study findings.
Results:
The corrected sinus node recovery time and sinoatrial conduction time were abnormal in 6.9% and 26.1% of patients, respectively. Thirty-seven (32.2%) had abnormal atrioventricular conduction. Intraventricular conduction was abnormal in 39 (33.9%). Approximately 48% had induced sustained ventricular arrhythmias, most of which were monomorphic (83.6%). Right bundle branch block was the most common morphology (52.7%). Fifty-one percent were associated with symptoms/hemodynamic instability, 60% required electrical cardioversion, and 27.3% needed overdrive suppression. The most common site of origin was the left ventricular inferoseptal wall (18.2%), followed by the left ventricular posterobasal wall (11%). Patients with an ejection fraction<40% had a 1.94-fold increased risk of ventricular arrhythmias compared to those with an ejection fraction>60% (OR: 1.94; 95%CI: 1.12-3.38; p=0.01). The presence of complex ventricular arrhythmias on Holter did not predict inducible ventricular arrhythmias.
Conclusions:
Chagas patients with a low ejection fraction have an increased risk of inducible ventricular arrhythmias. Sinus node dysfunction, and atrioventricular node and His-Purkinje conduction abnormalities occur in about one-third of patients. Complex ventricular arrhythmias on Holter were not associated with an increased risk of inducible ventricular arrhythmias.
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