Original articleRare Incidence of Ventricular Tachycardia and Torsades de Pointes in Hospitalized Patients With Prolonged QT Who Later Received Levofloxacin: A Retrospective Study
Section snippets
Patients and Methods
A total of 1004 consecutive hospitalized patients with a prolonged QTc (>450 ms) on the electrocardiogram (ECG) who subsequently received levofloxacin at Mayo Clinic Florida Hospital between October 9, 2009, and June 12, 2012, were included in this retrospective study. Patients were excluded if they were younger than 18 years, had an implanted defibrillator, had a history of sustained ventricular tachycardia, were using antiarrhythmic medications at the time of admission, received levofloxacin
Results
Patient characteristics and comorbid conditions for the 1004 study patients are summarized in Table 1. Patient medications on admission, levofloxacin information, and QTc information are summarized in Table 2. Levofloxacin was administered for a median of 3 days (range, 1-37 days). The QTc at admission was a median of 472 ms (range, 451-708 ms), and the median longest QTc during admission was 478 ms (range, 451-708 ms).
With a median time from the start of levofloxacin use to hospital discharge
Discussion
Levofloxacin is one of the most commonly prescribed antibiotics.6 Although the number of cases of torsades de pointes associated with the use of fluoroquinolones between January 1996 and May 2001 was 5.4 per 10 million prescriptions for levofloxacin,7 concerns about its potential arrhythmogenic effects remain. Manufacturers of levofloxacin have recommended that the medication be avoided in patients with known prolongation of the QT interval, patients with uncorrected hypokalemia, and patients
Conclusion
Levofloxacin administration either orally or intravenously was only rarely associated with short-term risk for ventricular tachycardia in those with prolonged QTc. These results suggest that when fluoroquinolones are deemed the appropriate treatment choice for an infection in a patient with a prolonged QTc, they may be considered a reasonable treatment option. Studies with longer follow-up are needed to assess the long-term risk for ventricular tachycardia in this patient population.
Acknowledgment
We thank Fred Kusumoto, MD, from the Division of Cardiovascular Disease at Mayo Clinic Florida for his review of the manuscript and electrocardiographic tracings.
References (28)
- et al.
Institution-wide QT alert system identifies patients with a high risk of mortality
Mayo Clin Proc
(2013) - et al.
Effects of fluoroquinolones on HERG currents
Eur J Pharmacol
(2000) - et al.
Effects of fluoroquinolones on HERG channels and on pancreatic beta-cell ATP-sensitive K+ channels
Toxicology
(2006) - et al.
Current concepts in the mechanisms and management of drug-induced QT prolongation and torsade de pointes
Am Heart J
(2007) - et al.
Effects of sparfloxacin, grepafloxacin, moxifloxacin, and ciprofloxacin on cardiac action potential duration
Eur J Pharmacol
(2000) - et al.
HRS/EHRA/APHRS expert consensus statement on the diagnosis and management of patients with inherited primary arrhythmia syndromes: document endorsed by HRS, EHRA, and APHRS in May 2013 and by ACCF, AHA, PACES, and AEPC in June 2013
Heart Rhythm
(2013) - et al.
Prescription of QT-prolonging drugs in a cohort of about 5 million outpatients
Am J Med
(2003) - et al.
QT interval prolongation associated with venlafaxine administration
Int J Cardiol
(2006) - et al.
Fluoroquinolones and the risk of serious arrhythmia: a population-based study
Clin Infect Dis
(2012) - et al.
QT prolongation and torsade de pointes induced by fluoroquinolones: infrequent side effects from commonly used medications
Cardiology
(2011)