Answer:
Beta-blockers are contraindicated in clients with known heart block because they can further slow down the heart rate and worsen the conduction disorder. Beta-blockers work by blocking the action of adrenaline on the heart, which reduces the heart rate and blood pressure.
In patients with heart block, the electrical conduction of the heart is impaired, leading to a slower heart rate. Beta-blockers can exacerbate this by decreasing the heart rate even further and potentially causing symptoms such as dizziness, fainting, and low blood pressure.
Furthermore, beta-blockers may worsen the heart block by slowing down the electrical impulses that regulate the heart rhythm. This can lead to the development of more serious arrhythmias, such as bradycardia or heart block.
Therefore, in patients with heart block, beta-blockers should be used with caution or may be contraindicated depending on the severity of the heart block and other individual patient factors. Other medications or treatment options may be more appropriate for managing the underlying heart condition.