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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following antiarrhythmic drugs mediates its effect by interfering with movement of calcium through the slow channel?
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The correct answer is  The slow channel for calcium assumes considerable importance in the region of the sinus node and AV node. For verapamil, this results in both antiarrhythmic and negative inotropic effects. Different classes of calcium channel blockers have differential effects on these slow channels, explaining the different clinical properties of the various calcium channel blocking drugs.