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Non-invasive evaluation of ventricular refractoriness and its dispersion during ventricular fibrillation in patients with implantable cardioverter defibrillator.

Luo J, Pripp CM, Hertervig E, Kongstad O, Ljungström E, Olsson SB, Yuan S - BMC Cardiovasc Disord (2004)

Bottom Line: In 6 patients, VERP was also measured during sinus rhythm at the RV apex and outflow tract (RVOT) using conventional extra stimulus technique.The estimated VERPs during induced VF in the RV apex were significantly shorter than that measured during sinus rhythm using extra stimulus technique.The maximal dispersion of the estimated VERPs during induced VF between the RV apex and posterior LV was that of 10 percentile VF interval (40 +/- 27 ms), that is markedly greater than the previously reported dispersion of ventricular repolarization without malignant ventricular arrhythmias (30-36 ms).

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Cardiology, University Hospital, Lund University, Lund, Sweden. Jijian.Luo@kard.lu.se

ABSTRACT

Background: Local ventricular refractoriness and its dispersion during ventricular fibrillation (VF) have not been well evaluated, due to methodological difficulties.

Methods: In this study, a non-invasive method was used in evaluation of local ventricular refractoriness and its dispersion during induced VF in 11 patients with VF and/or polymorphic ventricular tachycardia (VT) who have implanted an implantable cardioverter defibrillator (ICD). Bipolar electrograms were simultaneously recorded from the lower oesophagus behind the posterior left ventricle (LV) via an oesophageal electrode and from the right ventricular (RV) apex via telemetry from the implanted ICD. VF intervals were used as an estimate of the ventricular effective refractory period (VERP). In 6 patients, VERP was also measured during sinus rhythm at the RV apex and outflow tract (RVOT) using conventional extra stimulus technique.

Results: Electrograms recorded from the RV apex and the lower esophagus behind the posterior LV manifested distinct differences of the local ventricular activities. The estimated VERPs during induced VF in the RV apex were significantly shorter than that measured during sinus rhythm using extra stimulus technique. The maximal dispersion of the estimated VERPs during induced VF between the RV apex and posterior LV was that of 10 percentile VF interval (40 +/- 27 ms), that is markedly greater than the previously reported dispersion of ventricular repolarization without malignant ventricular arrhythmias (30-36 ms).

Conclusions: This study verified the feasibility of recording local ventricular activities via oesophageal electrode and via telemetry from an implanted ICD and the usefulness of VF intervals obtained using this non-invasive technique in evaluation of the dispersion of refractoriness in patients with ICD implantation.

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Simultaneous recordings of the bipolar electrograms showing distinct differences of the local ventricular electrical activities between the right ventricular apex and the posterior left ventricle during an induced episode of ventricular fibrillation in a patient (50 mm/sec). The ventricular fibrillation interval was shown in ms. RV = right ventricle, LV = left ventricle.
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Figure 1: Simultaneous recordings of the bipolar electrograms showing distinct differences of the local ventricular electrical activities between the right ventricular apex and the posterior left ventricle during an induced episode of ventricular fibrillation in a patient (50 mm/sec). The ventricular fibrillation interval was shown in ms. RV = right ventricle, LV = left ventricle.

Mentions: Thirty-four episodes of VF were induced, lasted from 8.2 to 14.2 seconds, in the 11 patients. Mean duration of the induced VF episodes was 10.3 ± 2.0 seconds. No complications were observed. During the episodes of the induced VF, electrograms from the endocardium at the RV apex and the lower esophagus behind the posterior LV manifested distinct local ventricular activities (Figure 1).


Non-invasive evaluation of ventricular refractoriness and its dispersion during ventricular fibrillation in patients with implantable cardioverter defibrillator.

Luo J, Pripp CM, Hertervig E, Kongstad O, Ljungström E, Olsson SB, Yuan S - BMC Cardiovasc Disord (2004)

Simultaneous recordings of the bipolar electrograms showing distinct differences of the local ventricular electrical activities between the right ventricular apex and the posterior left ventricle during an induced episode of ventricular fibrillation in a patient (50 mm/sec). The ventricular fibrillation interval was shown in ms. RV = right ventricle, LV = left ventricle.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC425578&req=5

Figure 1: Simultaneous recordings of the bipolar electrograms showing distinct differences of the local ventricular electrical activities between the right ventricular apex and the posterior left ventricle during an induced episode of ventricular fibrillation in a patient (50 mm/sec). The ventricular fibrillation interval was shown in ms. RV = right ventricle, LV = left ventricle.
Mentions: Thirty-four episodes of VF were induced, lasted from 8.2 to 14.2 seconds, in the 11 patients. Mean duration of the induced VF episodes was 10.3 ± 2.0 seconds. No complications were observed. During the episodes of the induced VF, electrograms from the endocardium at the RV apex and the lower esophagus behind the posterior LV manifested distinct local ventricular activities (Figure 1).

Bottom Line: In 6 patients, VERP was also measured during sinus rhythm at the RV apex and outflow tract (RVOT) using conventional extra stimulus technique.The estimated VERPs during induced VF in the RV apex were significantly shorter than that measured during sinus rhythm using extra stimulus technique.The maximal dispersion of the estimated VERPs during induced VF between the RV apex and posterior LV was that of 10 percentile VF interval (40 +/- 27 ms), that is markedly greater than the previously reported dispersion of ventricular repolarization without malignant ventricular arrhythmias (30-36 ms).

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Cardiology, University Hospital, Lund University, Lund, Sweden. Jijian.Luo@kard.lu.se

ABSTRACT

Background: Local ventricular refractoriness and its dispersion during ventricular fibrillation (VF) have not been well evaluated, due to methodological difficulties.

Methods: In this study, a non-invasive method was used in evaluation of local ventricular refractoriness and its dispersion during induced VF in 11 patients with VF and/or polymorphic ventricular tachycardia (VT) who have implanted an implantable cardioverter defibrillator (ICD). Bipolar electrograms were simultaneously recorded from the lower oesophagus behind the posterior left ventricle (LV) via an oesophageal electrode and from the right ventricular (RV) apex via telemetry from the implanted ICD. VF intervals were used as an estimate of the ventricular effective refractory period (VERP). In 6 patients, VERP was also measured during sinus rhythm at the RV apex and outflow tract (RVOT) using conventional extra stimulus technique.

Results: Electrograms recorded from the RV apex and the lower esophagus behind the posterior LV manifested distinct differences of the local ventricular activities. The estimated VERPs during induced VF in the RV apex were significantly shorter than that measured during sinus rhythm using extra stimulus technique. The maximal dispersion of the estimated VERPs during induced VF between the RV apex and posterior LV was that of 10 percentile VF interval (40 +/- 27 ms), that is markedly greater than the previously reported dispersion of ventricular repolarization without malignant ventricular arrhythmias (30-36 ms).

Conclusions: This study verified the feasibility of recording local ventricular activities via oesophageal electrode and via telemetry from an implanted ICD and the usefulness of VF intervals obtained using this non-invasive technique in evaluation of the dispersion of refractoriness in patients with ICD implantation.

Show MeSH
Related in: MedlinePlus