Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
The EKG in the Patient Treated with Ca Channel Blockers
Introduction
Electrocardiographic Findings
- In patients with sinus node disease, verapamil and diltiazem may cause severe bradycardia and even sinus arrest.
- Effect on rate depends on the balance between the effect on the conduction system and a reflex increase in the heart rate due to vasodilation.
- Diltiazem and verapamil may prolong the PR interval, nifedipine has no effect.
- No effect on the QRS or the QTc
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]