Facilitating assessment of QT interval duration during ventricular pacing

John A Chiladakis, Andreas Kalogeropoulos, Fani Zagkli, Nikolaos Koutsogiannis, Konstantinos Chouchoulis, Dimitrios Alexopoulos
Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology 2013, 15 (6): 907-14

AIMS: We aimed to facilitate the assessment of the QT interval duration during conventional right ventricular pacing (VP) by uncovering relationships with the underlying QT interval during intrinsic atrioventricular conduction (IC).

METHODS AND RESULTS: The study patients (n = 122, age 68 ± 11 years) were dual-chamber device recipients with preserved IC and narrow QRS complexes. Patients were classified into either 'normal-QT' (n = 70) or 'prolonged-QT' (n = 52) group. Incremental atrial pacing rates were exercised to record serial QT/JT intervals over 5 min periods in IC mode and then in VP mode. Six different QT correction methods for heart rate were applied to assess the effect (i) of pacing mode (IC vs. VP) and (ii) of heart rate on the derived QT(c)/JT(c) intervals by mixed-effects linear models. Following VP, the uncorrected QT/JT intervals as well as the JTc intervals shortened (P < 0.001), whereas the QTc intervals prolonged (P < 0.001). In both patient groups, the Framingham and Nomogram methods demonstrated the optimal balance to assess QTc, with low heart rate dependence during VP and minimal interaction between pacing mode and heart rate. The Rautaharju formula provided excellent correction for the QT changes induced by VP, but the QTc interval responded differently to rate changes in IC vs. VP mode. Bazett's formula exaggerated QTc/JTc rate dependency during VP.

CONCLUSION: The Framingham and Nomogram correction methods perform most reliably in assessing the underlying QT interval during IC from the ventricular paced QT interval.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"