The calculation of the corrected QT interval (QTc) is particularly problematic in patients during atrial fibrillation (AF). The aims of this study were to compare the QTc calculated using Bazett's formula in AF and sinus rhythm (SR) and determine whether alternative methods for QT correction were superior to Bazett's, in an effort to define the optimal method for QT correction in patients with AF. We evaluated consecutive patients with persistent AF admitted for initiation of dofetilide. The QT interval was corrected according to the following formulas: Bazett's, Fridericia, and Framingham. We compared the QTc interval on the last electrocardiogram in AF to the first electrocardiogram in SR. The cohort included 54 patients (age 60 ± 10 years, 80% men) with persistent AF for a median of 36 months. Bazett's overestimated QTc during AF compared with SR (464 ± 34 vs 445 ± 38 ms, p = 0.008); in contrast, Framingham underestimated it (385 ± 48 vs 431 ± 40 ms, p <0.001, respectively). However, there was no significant difference between the QTc interval in AF and SR when assessed by Fridericia (435 ± 33 vs 440 ± 35 ms, p = 0.46). There were 24 dofetilide dose reductions based on Bazett's QTc; this would have been avoided in 33% of patients had Fridericia been used. In conclusion, the commonly used Bazett's formula leads to an overestimation of the QTc during AF. This may result in unnecessary reduction in antiarrhythmic doses and thus drug efficacy. These data suggest that the Fridericia most closely approximates the QTc during AF to QTc during SR.
Pharmacology, Toxicology and Pharmaceutical Science
4
9%
Neuroscience
2
4%
Engineering
2
4%
Computer Science
1
2%
Other
0
0%
Unknown
13
28%
Attention Score in Context
Attention Score in Context
This research output has an Altmetric Attention Score of 10. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 12 February 2021.
All research outputs
#4,842,857
of 34,410,315 outputs
Outputs from American Journal of Cardiology
#2,487
of 15,871 outputs
Outputs of similar age
#35,631
of 244,014 outputs
Outputs of similar age from American Journal of Cardiology
#32
of 172 outputs
Altmetric has tracked 34,410,315 research outputs across all sources so far. Compared to these this one has done well and is in the 85th percentile: it's in the top 25% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 15,871 research outputs from this source. They typically receive more attention than average, with a mean Attention Score of 7.6. This one has done well, scoring higher than 84% of its peers.
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We're also able to compare this research output to 172 others from the same source and published within six weeks on either side of this one. This one has done well, scoring higher than 80% of its contemporaries.
