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Haemodynamics during a complete exercise induced atrioventricular block.
A Crisafulli1, F Melis, A C Lai
1Interdepartmental Centre for Sports Environments and Technologies, University of Cagliari, Italy.
An athlete experienced complete atrioventricular block during exercise but showed no cardiac output failure. Increased stroke index, driven by myocardial contractility, maintained normal cardiac output, demonstrating a compensatory mechanism.
Area of Science:
- Cardiology
- Exercise Physiology
- Sports Medicine
Background:
- Complete atrioventricular block (AVB) can impair cardiac function.
- Exercise testing is crucial for evaluating cardiovascular responses in athletes.
Observation:
- An athlete presented with complete AVB during an exercise test.
- No symptoms of cardiac output failure were observed during the event.
Findings:
- Impedance cardiography revealed a continuous increase in stroke index.
- This increase in stroke index compensated for the lack of heart rate response.
- Normal cardiac index values were maintained throughout the exercise due to enhanced myocardial contractility.
Implications:
- This case highlights the heart's adaptive capacity during exercise-induced arrhythmias.
- Myocardial contractility can play a significant role in maintaining cardiac output during complete AVB.
- Understanding these compensatory mechanisms is vital for managing athletes with conduction abnormalities.
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