Calcium Channel Blockers NCLEX Questions (NCLEX EXAM 2022)

1. Your patient is prescribed a calcium channel blocker. As the nurse you know that these medication works to block calcium channels in what areas of the body? Select all that apply: A. Vagal nerve cells B. Vascular smooth muscle C. Cardiac nodal tissue D. Peripheral nervous cells E. Cardiac myocytes The answers are B, C, and E. Calcium channel blockers work to block the L-type calcium channels in the vascular smooth muscle, cardiac myocytes, and cardiac nodal tissue. When the calcium channels of these areas are blocked they will decrease contraction of these cells, which will provide vasodilation, decrease in heart rate, and decrease in strength of heart contractions. Remember there are different types of calcium channel blockers, and some are more selective to the vascular smooth muscle, while some are more selective to the myocardium. 2. A patient is prescribed Verapamil for treatment of a supraventricular arrhythmia. As the nurse you know that this calcium channel blocker will help control the heart rate and rhythm by causing which of the following changes in the heart? Select all that apply: A. Negative inotropic effect B. Positive inotropic effect C. Negative chronotropic effect D. Positive chronotropic effect E. Negative dromotropic effect F. Positive dromotropic effect The answers are A, C, and E. Verapamil is a calcium channel blocker that is a non-dihydropyridine (phenylalkylamine). It decreases the contractility of the heart muscle cells, which decreases the strength of heart contractions, and this causes a NEGATIVE inotropic effect. In addition, Verapamil decreases the contraction of nodal tissue cells, specifically the SA and AV nodal tissue. Therefore, by decreasing the SA node (pacemaker of the heart), the heart rate will decrease, and this causes a NEGATIVE chronotropic effect. And by decreasing the AV node (gatekeeper), the speed of conduction will decrease, which will cause a NEGATIVE dromotropic effect.