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A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Symptomatic sick sinus syndrome due to guanethidine. Case report
Hypertension (Dallas, Tex. : 1979)
|September 1, 1979
Summary
Guanethidine medication can cause severe bradycardia (slow heart rate) and sinus arrest (stopped heartbeats). This rare side effect was observed in a patient with underlying heart conduction issues.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Guanethidine is an antihypertensive medication.
- Sinus bradycardia is a known side effect of guanethidine.
Observation:
- A patient developed severe symptomatic sinus bradycardia (20 bpm) and sinus arrest (4.4 seconds) while on guanethidine.
- Symptoms resolved upon drug discontinuation and recurred upon re-challenge.
Findings:
- The patient exhibited prolonged sinus node recovery time (1500 msec) and PR interval (0.28 seconds), indicating intrinsic conduction system disease.
- This extreme bradycardia, while rare, may be linked to pre-existing sinoatrial and atrioventricular node disease.
Implications:
- Clinicians should be aware of guanethidine's potential for severe bradycardia, especially in patients with pre-existing conduction abnormalities.
- This case highlights the importance of careful cardiac monitoring during guanethidine therapy.
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