The nurse caring for a patient with cardiovascular disease is aware of the many types of pharmacologic therapy used of treat CAD that decrease the oxygen demand of the myocardium and increase the oxygen supply

Question

The doctor has ordered Norvasc, a calcium channel blocking agent, for this patient. The nurse knows that calcium channel blockers have a variety of effects. One of the therapeutic effects is:
A) Decrease in sinoatrial node and atrioventricular node conduction and decrease in workload of the heart
B) Prevention of platelet aggregation and subsequent thrombosis
C) Reduction of myocardial oxygen consumption by blocking beta-adrenergic stimulation to the heart
D) Reduction of myocardial oxygen consumption, thus decreasing ischemia and relieving pain

Answer 1

Ans: A
Feedback: Calcium channel blocking agents decrease sinoatrial node automaticity and atrioventricular node conduction resulting in a slower heart rate and a decrease in the strength of the heart muscle contraction. These effects decrease the workload of the heart. They are also used to prevent and treat vasospasm. Antiplatelet and anticoagulation medications are administered to prevent platelet aggregation and subsequent thrombosis which impeded blood flow. Beta-blockers reduce myocardial consumption by blocking beta-adrenergic sympathetic stimulation to the heart. The result is reduced myocardial contractility (force of contraction) to balance the myocardium oxygen needs and supply. Nitrates reduce myocardial oxygen consumption, which decreases ischemia and relieves pain by dilating the veins and, in higher doses, the arteries.