Final answer:
Procainamide and diltiazem are used for managing atrial fibrillation. Diltiazem helps to slow the heart rate by blocking calcium channels while procainamide, a potassium channel blocker, is used when other treatments fail to alleviate symptoms.
Step-by-step explanation:
Procainamide and diltiazem are medications that are utilized in the context of cardiac dysrhythmias, particularly atrial fibrillation (a fib). When it comes to atrial fibrillation, diltiazem, which is a calcium channel blocker, is used to slow down the heart rate and thus can help in managing the symptoms. It works by inhibiting the flow of calcium ions within the heart, leading to a decrease in heart rate and an improvement in the efficiency of the heart's pumping action.
On the other hand, procainamide, which is a potassium channel blocker, is commonly used when other medications, such as ACE inhibitors and diuretics, have been ineffective in relieving heart failure symptoms associated with a fib. Potassium channel blockers impede the movement of potassium ions through voltage-gated K+ channels, affecting the repolarization phase of the cardiac action potential, which can help to restore a normal rhythm in the heart.