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β1-Adrenoceptor blocker aggravated ventricular arrhythmia.
Yan Wang1, Dimpi Patel, Dao Wu Wang
1Cardivascular Division, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P. R. China.
Pacing and Clinical Electrophysiology : PACE
|June 12, 2013
Summary
Preprocedural anxiety reduces idiopathic ventricular arrhythmias in some patients. Beta-blockers worsen arrhythmias, while isoprenaline inhibits them, showing a predictable response in these individuals.
Area of Science:
- Cardiology
- Electrophysiology
- Pharmacology
Background:
- Idiopathic ventricular arrhythmias can be influenced by various factors.
- Preprocedural anxiety has been anecdotally observed to decrease arrhythmia incidence.
- Understanding the mechanisms behind anxiety-related arrhythmia modulation is crucial.
Observation:
- Six patients with idiopathic ventricular arrhythmias showed >90% reduction in ectopic beats during preprocedural anxiety.
- This reduction was normalized to baseline (100%) for comparison.
- Ventricular premature beats per hour (VPH) quantified arrhythmia burden.
Findings:
- Beta-1 adrenoceptor blockers (β1-blockers) aggravated arrhythmias (104.6% to 97.9% VPH).
- Isoprenaline infusion rapidly inhibited arrhythmias (97.9% to 1.6% VPH).
- β1-blockers reversed isoprenaline's inhibitory effect, increasing VPH (1.6% to 120.9%).
Implications:
- Patients with idiopathic ventricular arrhythmias may exhibit anxiety-dependent modulation.
- This response involves a predictable sequence of β1-blocker aggravation and catecholamine inhibition.
- Findings suggest distinct adrenergic pathway involvement in specific arrhythmia types.
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