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Published on: December 11, 2019
TBC: A simple algorithm to rule out abnormalities in electrocardiograms of patients with pacemakers
Javier Higueras1, Carmen Olmos, Julián Palacios-Rubio
1Hospital Clinico San Carlos, Madrid, Spain. javierhnb@yahoo.es.
Background:
The aim of the study was to create a straightforward method to rule out abnormalities in electrocardiograms (ECGs) performed in patients with pacemakers.
Methods:
The TBC method screens the ECG for any of the following findings: Tachycardia with pacing spikes, Bradycardia without spikes and Chaos with spikes unrelated to QRS-T complexes. T was considered to advise for patient assessment and B and C to require referral for urgent pacemaker evaluation. The diagnostic accuracy of the algorithm was validated using a cohort of 151 ECGs with normal and dysfunctional pacemakers. The effect of the algorithm was then evaluated for diagnostic skills and management of patients with pacemakers by non-cardiologists, comparing their diagnostic accuracy before and after teaching the algorithm.
Results:
The TBC algorithm had a sensitivity of 86% and a specificity of 94% in diagnosing a malfunctioning pacemaker. The diagnostic skills and patient referral were significantly improved (74.8% vs. 89.5%, p < 0.001; and 57.4% vs. 83%, p < 0.001).
Conclusions:
TBC is an easy to remember and apply method to rule out severe abnormalities in ECGs of patients with pacemakers. TBC algorithm has a very good diagnostic capability and is easily applied by non-expert physicians with good results.
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