Title:Empirical Antimicrobial Therapy and QTc Interval Prolongation in Emergency
Medicine
Volume: 17
Issue: 1
Author(s): Marianna Suppa and Luca Marino*
Affiliation:
- Mechanical and Aerospace Engineering Department and Emergency Department, Policlinico “Umberto I”, University “La Sapienza”, Rome, Italy
Keywords:
QTc prolongation, risk factors, antibiotic therapy, arrhythmia, drug safety, emergency medicine.
Abstract:
Background: QTc prolongation is common in dangerous clinical conditions, associated
with an increased risk of life-threatening arrhythmia torsades de pointes. The goal of this short communication
is to evaluate the principal causes of risk of QTc prolongation that are observed in an
emergency department and discuss the differences between drug- and non-drug-associated factors.
Methods: The retrospective analysis was carried out on 130 patients that presented a QTc prolongation
(>480 ms for man and >470 for female, respectively), admitted to the emergency department
of a single Italian hospital. Patients with pace-maker (22) were excluded from this study. For each
patient, a minimum of 3 ECGs (12 leads) were recorded. Attention was paid on electrolytes disturbances
and to the pharmacotherapy, with a particular emphasis to the use of antibiotics.
Results: Mean age of the patients was 79.6 years (SD=11.3) and females and males were almost
equally present (46.6% F, 53.7% M). The average QTc value was 492.2 ms (493.3 ms F, 492.8 M).
The patients were divided in those with electrolytes disturbances (24.0%), antimicrobial therapy
(35.2%), both antimicrobial therapy and electrolytes disturbances (24.1%), and other causes of
QTc prolongation (16.7%).
Conclusion: This analysis shows the relevance of the empirical therapy established at the admission,
in particular for infective diseases, as an important risk factor for the prolongation of QTc.
Other factors that can increase the risk are electrolytes alterations, advanced age, cardiovascular diseases,
and drug-drug interaction.
