A case report of QT prolongation with glycopyrronium bromide in a patient with chronic tamoxifen use.
BACKGROUND
Glycopyrronium bromide has recently been approved as a once daily maintenance inhalation therapy for moderate to severe chronic obstructive pulmonary disease (COPD). Efficacy and safety trial data have found rare cases of significant QT prolongation. To our knowledge, we describe the first case report of QT prolongation >600 ms with initiation of glycopyrronium bromide in a real world setting.


METHODS
A 78-year-old female with moderate COPD recently started on glycopyrronium bromide, presented to Emergency Department (ED) with syncope. Her past medical history was significant for a left total mastectomy and she had been on Tamoxifen for 9 months. One day prior to her presentation, she had visited a naturopathic clinic for a vitamin infusion resulting in emesis. The following day she continued to feel dizzy and had a witnessed syncopal episode without any reported cardiac or neurological symptoms preceding the event or after regaining consciousness. In the emergency department, she reported dizziness and was found to be hypotensive. Her symptoms completely resolved with intravenous fluids. Lab work was normal however her electrocardiogram (ECG) demonstrated a QTc interval of 603 and 631 ms (Friderica and Bazett's respectively) with a normal QT interval on her baseline ECG prior to initiating Tamoxifen. She was admitted to the Cardiology service for further work-up of QT prolongation. Her syncope was felt to be due to orthostatic hypotension and the QT prolongation secondary to medications, which were both discontinued during her admission. After 2 days, her QT interval normalized consistent with the half-life of Glycopyrronium bromide (13-57 h) compared to Tamoxifen (8-14 days).


CONCLUSIONS
Glycopyrronium bromide is guideline recommended as first line therapy for prevention of exacerbation in moderate to severe COPD however safety data had been limited to select populations. This case report highlights the need for future studies to identify high-risk populations at potential risk of life-threatening arrhythmias who may benefit from periodic ECG surveillance.
Division of Cardiology, Libin Cardiovascular Institute, University of Calgary, Calgary, AB, Canada.
Michael H
MH
Chiu
Division of Cardiology, University of Alberta, Edmonton, AB, Canada.
Nawaf S
NS
Al-Majed
Department of Internal Medicine, Faculty of Medicine, University of Alberta, Edmonton, AB, Canada.
Ryan
R
Stubbins
Department of Pharmacy, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, AB, Canada.
Dylan
D
Pollmann
Division of Cardiology, University of Alberta, Edmonton, AB, Canada. rsandhu2@ualberta.ca.
Roopinder K
RK
Sandhu
D000280:Administration, Inhalation; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006024:Glycopyrrolate / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D008133:Long QT Syndrome / Q000139:chemically induced / Q000175:diagnosis*; D018727:Muscarinic Antagonists / Q000008:administration & dosage / Q000009:adverse effects; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy; D020845:Selective Estrogen Receptor Modulators / Q000009:adverse effects; D013575:Syncope / Q000139:chemically induced / Q000175:diagnosis*; D013629:Tamoxifen / Q000009:adverse effects*
D018727:Muscarinic Antagonists; D020845:Selective Estrogen Receptor Modulators; D013629:Tamoxifen; D006024:Glycopyrrolate
Chronic obstructive pulmonary disease; Glycopyrronium bromide (Seebri); NVA237; QT prolongation