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Endotoxin Activity Assay for the Detection of Whole Blood Endotoxemia in Critically Ill Patients
Published on: June 24, 2019
Lethal and edema toxins of anthrax induce distinct hemodynamic dysfunction
Linley E Watson1, Jonathan Mock, Hind Lal
1Division of Cardiology, Scott and White Memorial Hospital, Scott, Sherwood and Brindley Foundation and Cardiovascular Research Institute, Texas A & M University System, Health Science Center College of Medicine, Temple, TX 76502, USA.
Summary
Anthrax toxins, lethal toxin (LeTx) and edema toxin (EdTx), impact cardiovascular function differently. LeTx impairs heart contractility, while EdTx reduces blood volume without directly affecting the heart muscle.
Area of Science:
- Cardiovascular Physiology
- Microbiology
- Toxicology
Background:
- Bacillus anthracis toxins, lethal toxin (LeTx) and edema toxin (EdTx), are implicated in severe hypotension during anthrax infection.
- Understanding the specific cardiovascular effects of these toxins is crucial for developing targeted treatments.
Purpose of the Study:
- To investigate and characterize the distinct cardiovascular effects of LeTx and EdTx.
- To differentiate the hemodynamic dysfunction caused by each toxin.
Main Methods:
- Echocardiography was employed to assess cardiac function in response to LeTx and EdTx exposure.
- Key echocardiographic parameters including ejection fraction, ventricular volumes, cardiac output, and myocardial velocities were measured.
Main Results:
- LeTx significantly reduced ejection fraction, diastolic function, and contractility, indicating impaired left ventricular systolic function.
- EdTx significantly decreased left ventricular volumes and cardiac output (reduced stroke volume) but did not alter ejection fraction or contractility, suggesting preload reduction without direct myocardial toxicity.
- LeTx induced left ventricular dilation, while EdTx did not.
Conclusions:
- LeTx directly impairs left ventricular systolic function.
- EdTx primarily affects cardiac preload without direct myocardial toxicity.
- LeTx and EdTx induce distinct patterns of hemodynamic dysfunction in anthrax infection.
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