Differential Entrainment Distinguishes Atrioventricular Nodal Reentry Tachycardia from Atrioventricular Reentrant Tachycardia
ABSTRACT Entrainment from the right ventricular (RV) apex and the base has been used to distinguish atrioventricular reentrant tachycardia (AVRT) from atrioventricular nodal reentry tachycardia (AVNRT). The difference in the entrainment response from the RV apex in comparison with the RV base has not been tested.
Fifty-nine consecutive patients referred for ablation of supraventricular tachycardia (SVT) were included. Entrainment of SVT was performed from the RV apex and base, pacing at 10-40-ms faster than the tachycardia cycle length. SA interval was calculated from stimulus to earliest atrial electrogram. Ventricle to atrium (VA) interval was measured from the RV electrogram (apex and base) to the earliest atrial electrogram during tachycardia. The SA-VA interval from apex and base was measured and the difference between them was calculated.
Thirty-six AVNRT and 23 AVRT patients were enrolled. Mean age was 44 ± 12 years; 52% were male. The [SA-VA]apex-[SA-VA]base was demonstrable in 84.7% of patients and measured -9.4 ± 6.6 in AVNRT and 10 ± 11.3 in AVRT, P < 0.001. The difference was negative for all AVNRT cases and positive for all septal accessory pathways (APs).
The difference between entrainment from the apex and base is readily performed and is diagnostic for all AVNRTs and septal APs.
SourceAvailable from: sciencedirect.com[Show abstract] [Hide abstract]
ABSTRACT: Introduction Right ventricular entrainment represents a useful tool for differentiating atrioventricular nodal re-entrant tachycardia (AVNRT) from orthodromic re-entrant tachycardia (ORT) using an accessory pathway. However, inability to entrain PSVT by pacing can be observed in some patients. Aim of study Assessing whether the resetting response to SVT by single or double right ventricular extra-stimuli is a useful maneuver to differentiate AVNRT from OAVRT by calculating the difference between the stimulus-atrial interval during resetting of SVT and the VA interval during SVT (SA–VA). Methods Electrophysiological study was conducted with a calculation of the SA–VA interval after resetting of the tachycardia by ventricular extra stimulus and differential entrainment from RV apex and base, then comparing the two methods regarding sensitivity and specificity in differentiating AVNRT from OAVRT conducted on 25 patients. Results Measuring the SA–VA interval after resetting of the tachycardia by an extra stimulus during the His refractoriness during the tachycardia showed in AVNRT a mean of 145.76 ± 31.53 and in OAVRT a mean ± SD of 91.52 ± 12.79 with a high statistical significance, with a cutoff point of 107 ms above which the SVT is expected to be AVNRT, and below which OAVRT. Using this technique could differentiate AVNRT from OAVRT with an overall sensitivity of 100% and specificity of 76.47%, in comparison to a specificity of 81.8% when using the technique of differential entrainment from RV apex and base. Conclusion Resetting of SVT by ventricular extra-stimuli is a useful maneuver for differentiating AVNRT from ORT and is applicable even when entrainment is impossible.12/2013; 65(4):271–274. DOI:10.1016/j.ehj.2013.02.003
[Show abstract] [Hide abstract]
ABSTRACT: Objectives: The purpose of this study was to prospectively evaluate the feasibility and diagnostic value of right ventricular overdrive pacing (RVOP) during supraventricular tachycardia (SVT) using a 2-catheter approach with automatic pacing from the right ventricular inflow (RVIT) and outflow tract (RVOT). Methods: One hundred and thirty-six consecutive patients (with 138 arrhythmias, mean age 36 ± 20 years, range 4-95) were enrolled in this study. Only coronary sinus and ablation catheters were used. RVOP was delivered from RVIT and then from RVOT. Each attempt consisted of 10 synchronized beats delivered at a cycle length of 10-40 ms longer than the tachycardia cycle length. Results: RVOP was sufficient to confirm the transition zone within the first 9 beats in the majority of SVTs. Atrial perturbation (acceleration, delayed) in the transition zone was detected in all patients with orthodromic atrioventricular (AV) reentry. Patients with typical AV nodal reentry, atypical AV nodal reentry and atrial tachycardia did not show atrial timing perturbation during fusion complexes of RVOP. Conclusions: Synchronized RVOP from RVIT or RVOT is an easy and accurate method for the quick and reliable differential diagnosis of SVT in various clinical settings, particularly when only a limited number of catheters are used. © 2014 S. Karger AG, Basel.Cardiology 09/2014; 129(2):93-102. DOI:10.1159/000362786 · 2.04 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: This paper is the second part of a review of the phenomena of resetting and entrainment of reentrant arrhythmias. It describes the practical and clinical uses of resetting and entrainment, including the results of a variety of studies for these purposes. Given the amount of information generated, it is out of the scope of this review to comment in detail about each of the published studies. We rather present the basis for each described clinical use and for each type of arrhythmia in which these phenomena have been used with illustrative examples. The review covers: resetting response patterns; resetting/entrainment and termination; resetting/entrainment, fusion, and reentry; analysis of the postpacing interval; concealed entrainment; resetting/entrainment as an aid in the differential diagnosis among different arrhythmic mechanisms; usefulness of these phenomena in arrhythmic mechanisms other than macrorreentry. Finally, we make some comments about the recent use of these phenomena and propose two new criteria for entrainment recognition.Pacing and Clinical Electrophysiology 01/2013; DOI:10.1111/pace.12075 · 1.75 Impact Factor