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Influence of thoracic paravertebral block on cardiac repolarization
Aleksander P Remesz1,2, Kamil S Drucis3,4, Radosław Owczuk5,6
1Department of Anesthesiology and Intensive Therapy, Faculty of Medicine, Medical University of Gdańsk, Smoluchowskiego 17, 80-214, Gdańsk, Poland.
Scientific Reports
|July 6, 2026
Summary
Thoracic paravertebral blockade (PVB) on the right side prolonged the QT interval and QTc, impacting cardiac repolarization. Left-sided PVB showed no significant changes, suggesting side-dependent autonomic effects on the heart.
Area of Science:
- Cardiology
- Autonomic Nervous System
- Anesthesiology
Background:
- Autonomic regulation impacts cardiac repolarization, with prolonged QT intervals linked to arrhythmias.
- Pharmacological disruption of autonomic nerves can modify these effects.
- Thoracic paravertebral blockade (PVB) is a regional anesthesia technique affecting sympathetic nerves.
Purpose of the Study:
- To investigate the influence of unilateral thoracic paravertebral blockade (PVB) on cardiac repolarization.
- To assess the effect of PVB on the QT interval and transmural dispersion of repolarization (TDR).
- To determine if these effects differ based on the side of the blockade.
Main Methods:
- Sixty female patients undergoing unilateral breast surgery received PVB at T3 with ropivacaine.
- A 12-lead ECG was recorded pre- and post-blockade (T1-T4 dermatomes).
- Analysis included QT, corrected QT (QTc), Tp-e interval, and Tp-e/QT ratio.
Main Results:
- Right-sided PVB led to significant QT and QTc prolongation, decreased heart rate, and reduced blood pressure.
- Left-sided PVB did not cause significant repolarization or hemodynamic changes.
- No significant changes in Tp-e or Tp-e/QT ratio were observed in either group.
Conclusions:
- Unilateral thoracic paravertebral blockade demonstrates side-dependent effects on cardiac repolarization and hemodynamics.
- Right-sided PVB may influence cardiac repolarization, warranting further investigation.
- Short observation periods necessitate further studies to fully elucidate PVB's cardiac effects.
Keywords:
Cardiac arrhythmiaConduction anesthesiaRegional anesthesiaRopivacaineThoracic paravertebral blockTorsade de pointesMore Related Videos
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