Which anti-hypertensive class is contraindicated in patients with heart blocks?

Beta-blockers are the correct answer because they are known to have a direct effect on the electrical conduction system of the heart. They work by blocking beta-adrenergic receptors, which can slow down heart rate and decrease conduction through the atrioventricular (AV) node. In patients with existing heart blocks, especially first-degree AV block or higher, the use of beta-blockers may exacerbate the condition, making it more difficult for electrical impulses to travel from the atria to the ventricles. This can increase the risk of more severe bradycardia or even more advanced blocks, which can be life-threatening.

While calcium channel blockers can also affect heart rate and AV conduction, they are generally used under careful monitoring and are not as strictly contraindicated as beta-blockers. Diuretics and angiotensin receptor blockers (ARBs) do not significantly impact the heart’s conduction system and are not contraindicated in patients with heart blocks. Therefore, beta-blockers represent the class of anti-hypertensive agents that should be used with caution or avoided in patients with heart block due to their potential to worsen the condition.