BACKGROUND Timolol Maleate is a non-selective beta-adrenergic blocker that is commonly used to treat open-angle glaucoma. Despite its topical administration, ophthalmic timolol enters systemic circulation and produces a systemic beta-adrenergic blockade. We report a case of long-term timolol use that uncovered and worsened an underlying cardiac conduction defect demonstrated as a third degree atrioventricular (AV) block. CASE PRESENTATION A 62-year old male with a 13-year history of glaucoma was hospitalized due to shortness of breath, dizziness, and amaurosis. Electrocardiography indicated a heart rate (HR) of 29 bpm with complete atrioventricular (AV) block, and the HR was significantly increased with the treatment of isoprenaline. However, the patient experienced bradycardic episodes (- 20 Δbpm) immediately after self-administration of timolol eye drops. The AV block and bradycardia resolved 48-h after timolol cessation. The man was discharged 1 week later with an asymptomatic first-degree A-V block. However, he presented with a worsened A-V block at his one-year checkup. CONCLUSION We conclude that chronic topical timolol administration may aggravate a cardiac conduction defect leading to an AV block that is only temporarily resolved by timolol cessation. Patients taking timolol should be routinely monitored for cardiovascular aberrations and if any detected, immediately discontinue timolol therapy. Individuals experiencing timolol induced cardiovascular side effects should receive long term follow-up even if symptoms resolve, as they may be indicative of an underlying conduction defect.

中文翻译：

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噻吗洛尔滴眼液引起的完全房室传导阻滞：一例病例报告和文献复习。

背景技术马来酸替莫洛尔是一种非选择性的β-肾上腺素能阻滞剂，通常用于治疗开角型青光眼。尽管局部用药，但眼科噻吗洛尔仍进入全身循环并产生全身性β-肾上腺素能阻滞剂。我们报告了长期使用噻吗洛尔的情况，这种情况未发现并加重了潜在的心脏传导缺陷，表现为三度房室（AV）阻滞。病例介绍一名患有青光眼13年病史的62岁男性因呼吸急促，头昏眼花和黑皮肤而住院。心电图检查显示心率（HR）为29 bpm，伴有完全房室（AV）阻滞，并且使用异丙肾上腺素治疗后，HR显着增加。然而，服用噻吗洛尔滴眼液后，患者立即经历了心动过缓发作（-20Δbpm）。噻吗洛尔停药后48小时，房室传导阻滞和心动过缓消失。该名男子在1周后因无症状的一级房室传导阻滞而出院。但是，在一年的检查中，他出现了恶化的房室传导阻滞。结论我们得出的结论是，长期局部使用噻吗洛尔可能会加重心脏传导缺陷，从而导致仅通过噻吗洛尔停止才能暂时解决的房室传导阻滞。服用替莫洛尔的患者应常规监测心血管畸变，如果发现任何异常，应立即停止使用替莫洛尔治疗。出现噻吗洛尔诱发的心血管副作用的患者，即使症状缓解，也应接受长期随访，