Korean J Med.  2009 Aug;77(Suppl 1):S249-S253.

Successful pharmacotherapy for asthma exacerbation in an asthmatic patient with long QT syndrome

• Kim HK
• Cho DK
• Lee WJ
• Myung DS
• Han ER
• Choi IS
• Koh YI

Abstract

beta -Blockers can cause bronchospasm in asthma. beta 2-agonists prolong the QT interval and alter the clinical course of long QT syndrome (LQTS). We report a case of asthma exacerbation treated cautiously with beta 2-agonists in a patient with LQTS, while LQTS was controlled with low-dose beta 1-antagonists. A 31-year-old woman with LQTS visited the emergency room for asthma exacerbation. FEV1 was 0.5 L (18%) and QTc interval was 520 ms. Low doses of salbutamol or salmeterol were used and gradually increased, while monitoring the QT interval. Simultaneously, a low dose of atenolol was maintained. FEV1 was increased to 2.2 L (83%) without further QT prolongation or cardiac events. The case suggests that lower doses of beta 1-antagonists can be tried for cardiac diseases, even in the presence of asthma exacerbations. beta 2-Agonists may be initiated at lower doses and, if tolerated, the dose can be increased in asthmatic patients with a risk for QT prolongation.

Keyword

Asthma; Long QT syndrome; Adrenergic beta-agonists; Adrenergic beta-antagonists

MeSH Terms

Adrenergic beta-Agonists
Adrenergic beta-Antagonists
Adult
Albuterol
Asthma
Atenolol
Bronchial Spasm
Emergencies
Female
Heart Diseases
Humans
Long QT Syndrome
Salmeterol Xinafoate
Adrenergic beta-Agonists
Adrenergic beta-Antagonists
Albuterol
Atenolol