What is the treatment for open-angle glaucoma in a patient with bradycardia (abnormally slow heart rate) and first-degree atrioventricular (AV) block?

From the Guidelines

For a patient with open-angle glaucoma who also has bradycardia and first-degree AV block, prostaglandin analogs are the preferred first-line treatment. Medications such as latanoprost 0.005% (one drop in the affected eye(s) once daily at bedtime), travoprost 0.004%, or bimatoprost 0.01% are recommended 1. These medications lower intraocular pressure by increasing uveoscleral outflow without affecting heart rate or cardiac conduction.

Key Considerations

• Beta-blockers like timolol should be avoided as they can worsen bradycardia and AV block, as noted in a study on individualized beta-blocker treatment 1.
• If additional IOP lowering is needed, consider adding a carbonic anhydrase inhibitor such as dorzolamide 2% (one drop three times daily) or brinzolamide 1%, or a selective alpha-2 agonist like brimonidine 0.1-0.2% (one drop two to three times daily) 1.
• However, brimonidine should be used cautiously as it may rarely cause bradycardia.

Monitoring and Follow-up

• Regular monitoring of intraocular pressure every 3-4 months is essential, with a target reduction of at least 20-30% from baseline.
• The patient should also have periodic cardiac evaluation to ensure the glaucoma treatment isn't adversely affecting their cardiac condition. This approach prioritizes effective glaucoma management while minimizing the risk of exacerbating the patient's underlying cardiac conduction abnormalities.

From the FDA Drug Label

The dosage employed in the treatment of chronic simple (open-angle) glaucoma ranges from 250 mg to 1 g of acetazolamide per 24 hours, usually in divided doses for amounts over 250 mg. There is no direct information in the provided drug labels regarding the treatment of open-angle glaucoma in a patient with bradycardia (abnormally slow heart rate) and first-degree atrioventricular (AV) block.

• The labels do provide dosage information for open-angle glaucoma, but do not address the specific conditions of bradycardia and first-degree AV block 2.
• Therefore, no conclusion can be drawn regarding the treatment of open-angle glaucoma in this specific patient population.

From the Research

Treatment Options for Open-Angle Glaucoma

The treatment for open-angle glaucoma in a patient with bradycardia (abnormally slow heart rate) and first-degree atrioventricular (AV) block involves the use of medications that reduce intraocular pressure (IOP) without exacerbating the patient's cardiac condition.

• Prostaglandin analogues: Latanoprost is a prostaglandin analogue that has been shown to be effective in reducing IOP in patients with open-angle glaucoma or ocular hypertension 3. It does not produce the cardiopulmonary adverse effects associated with beta-blockers, making it a suitable option for patients with bradycardia and first-degree AV block.
• Alpha 2-agonists: Brimonidine is an alpha 2-agonist that has been shown to be effective in lowering IOP in patients with open-angle glaucoma 4. It has a peak IOP-lowering efficacy comparable to that of timolol, but without timolol's adverse cardiopulmonary side effects.
• Other medications: Other medications such as bimatoprost, travoprost, and tafluprost have also been shown to be effective in reducing IOP in patients with open-angle glaucoma 5. However, the choice of medication should be based on the individual patient's needs and medical history.

Considerations for Patients with Bradycardia and First-Degree AV Block

When treating patients with open-angle glaucoma who also have bradycardia and first-degree AV block, it is essential to consider the potential effects of the medication on the patient's cardiac condition.

• Avoidance of beta-blockers: Beta-blockers, such as timolol, can exacerbate bradycardia and should be avoided in patients with this condition 3, 4.
• Monitoring of heart rate and blood pressure: Patients with bradycardia and first-degree AV block should be monitored closely for changes in heart rate and blood pressure when starting a new medication for open-angle glaucoma.