Cardiovascular Journal of Africa: Vol 26 No 6 (November/December 2015)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 26, No 6, November/December 2015

210

AFRICA

Management and outcome of topical beta-blocker-

induced atrioventricular block

Kazım Serhan Özcan, Barı

Güngör, Damirbek Osmonov, Ahmet

lker Tekke

in, Servet Altay, Ahmet

Ekmekçi, Ercan Toprak, Ersin Yıldırım, Nazmi Çalık, Ahmet Taha Alper, Kadir Gürkan,

zzet Erdinler

Abstract

Background:

Topical beta-blockers have a well-established

role in the treatment of glaucoma. We aimed to investigate the

outcome of patients who developed symptomatic atrioven-

tricular (AV) block induced by topical beta-blockers.

Methods:

All patients admitted or discharged from our insti-

tution, the Siyami Ersek Training and Research Hospital,

between January 2009 and January 2013 with a diagnosis of

AV block were included in the study. Subjects using ophthal-

mic beta-blockers were recruited and followed for permanent

pacemaker requirement during hospitalisation and for three

months after discontinuation of the drug. A permanent pace-

maker was implanted in patients in whom AV block persisted

beyond 72 hours or recurred during the follow-up period.

Results:

A total of 1 122 patients were hospitalised with a

diagnosis of AV block and a permanent pacemaker was

implanted in 946 cases (84.3%) during the study period.

Thirteen patients using ophthalmic beta-blockers for the

treatment of glaucoma and no other rate-limiting drugs were

included in the study. On electrocardiography, eight patients

had complete AV block and five had high-degree AV block.

The ophthalmic beta-blockers used were timolol in seven

patients (55%), betaxolol in four (30%), and cartelol in two

cases (15%). The mean duration of ophthalmic beta-blocker

treatment was 30.1

15.9 months. After drug discontinuation,

in 10 patients the block persisted and a permanent pacemaker

was implanted. During follow up, one more patient required

pacemaker implantation. Therefore in total, pacemakers were

implanted in 11 out of 13 patients (84.6%). The pacemaker

implantation rate did not differ according to the type of topi-

cal beta-blocker used (

0.37). The presence of infra-nodal

block on electrocardiography was associated with higher rates

of pacemaker implantation.

Conclusion:

Our results indicate that topical beta-blockers

for the treatment of glaucoma may cause severe conduction

abnormalities and when AV block occurs, pacemaker implan-

tation is required in a high percentage of the patients.

Keywords:

beta-blockers, glaucoma, drug-induced block, pace-

maker implantation

Submitted 17/1/15, accepted 16/3/15

Cardiovasc J Afr

2015;

: 210–213

www.cvja.co.za

DOI: 10.5830/CVJA-2015-030

Topical beta-blockers have a well-established role in the treatment

of glaucoma and are frequently used as first-line therapy for the

reduction of associated ocular hypertension.

1,2

While systemic

concentration after administration of topical beta-blockers is

low in comparison to that achieved with oral beta-blockers,

cardiovascular, respiratory, central nervous system and metabolic

side effects may still occur.

Topical beta-blockers have been

shown to decrease heart rate and blood pressure in comparison

to placebo.

Cardiovascular effects may be augmented with

systemic combination therapy with other heart rate-blocking

agents, such as beta-blockers and calcium channel blockers.

In the literature, there are several case reports indicating

the possible relationship between topical beta-blockers and the

development of severe bradyarrhythmias, such as third-degree

atrioventricular (AV) block and sick sinus syndrome.

6-9

However,

little is known about the incidence and prognosis of severe

bradyarrhythmias induced by topical beta-blockers. In this

trial, we aimed to investigate the outcome of patients who were

hospitalised with a diagnosis of symptomatic AV block while

receiving topical beta-blockers.

Methods

All patients who were hospitalised in our institution, the Siyami

Ersek Training and Research Hospital, between January 2009

and January 2013 with a diagnosis of AV block or symptomatic

bradyarrhythmia were reviewed. The site of AV block was

diagnosed by surface electrocardiography, as previously

described

10-13

(Table 1). Patients who had symptomatic (fatigue,

faintness, dyspnoea and syncope) type II second- or third-degree

AV block, 2:1 AV block, atrial fibrillation with bradycardia

(average heart rate

≤

40 beats/min on 24-hour Holter monitoring)

were included in this study. Patients with vasovagal syncope,

concomitant myocardial infarction, electrolyte abnormalities or

digitalis toxicity were excluded.

Department of Cardiology, Derince Training and Research

Hospital, Kocaeli, Turkey

Kazım Serhan Özcan, MD,

serhandr@gmail.com

; serhan_oz@

yahoo.com

Department of Cardiology, Siyami Ersek Cardiovascular

and Thoracic Surgery Centre, Istanbul, Turkey

Barı

Güngör, MD

Ahmet

lker Tekke

in, MD

Servet Altay, MD

Ahmet Ekmekçi, MD

Ercan Toprak, MD

Ersin Yıldırım, MD

Nazmi Çalık, MD

Ahmet Taha Alper, MD

Kadir Gürkan, MD

zzet Erdinler, MD

Department of Cardiology, Almaty Sema Hospital, Almaty,

Kazakhstan

Damirbek Osmonov, MD