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S B Olsson - One of the best experts on this subject based on the ideXlab platform.

  • right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European Heart Journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    AIMS: Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. METHODS AND RESULTS: Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3 x 4 cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolf-Parkinson-White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2.2 to 4.2 cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomogeneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88 +/- 9 cm.s-1 (mean +/- SD), ranging between 68 +/- 4 and 103 +/- 3 cm.s-1 during sinus rhythm. Mean conduction velocity during atrial pacing was 81 +/- 16 cm.s-1 at a propagation direction of 0 degree, 74 +/- 14 cm.s-1 at a 90 degrees direction, 79 +/- 12 cm.s-1 at 180 degrees and 78 +/- 20 cm.s-1 at 270 degrees, where 0 degree was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P < 0.05) than during atrial pacing at the 90 degrees and 180 degrees directions but not compared to atrial pacing at 0 degree or 270 degrees. There was no significant difference in mean conduction velocity in different directions during atrial pacing. CONCLUSION: Although anisotropy was documented during conduction velocity in individual cases, conduction velocity was not dependent on propagation direction at the epicardial right atrial free wall in patients with stable sinus rhythm. These findings do not exclude the presence of internodal preferential pathways as these are located sub-epicardially and a marked transmural discordance in activation has previously been documented in the vicinity of such pathways.

  • Right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European heart journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    Aims Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. Methods and Results Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3×4cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolff–Parkinson–White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2·2 to 4·2cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomo-geneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88±9cm.s−1(mean±SD), ranging between 68±4 and 103±3cm.s−1during sinus rhythm. Mean conduction velocity during atrial pacing was 81±16cm.s−1at a propagation direction of 0°, 74±14cm.s−1at a 90° direction, 79±12cm.s−1at 180° and 78±20cm.s−1at 270°, where 0° was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P

A Hansson - One of the best experts on this subject based on the ideXlab platform.

  • right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European Heart Journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    AIMS: Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. METHODS AND RESULTS: Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3 x 4 cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolf-Parkinson-White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2.2 to 4.2 cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomogeneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88 +/- 9 cm.s-1 (mean +/- SD), ranging between 68 +/- 4 and 103 +/- 3 cm.s-1 during sinus rhythm. Mean conduction velocity during atrial pacing was 81 +/- 16 cm.s-1 at a propagation direction of 0 degree, 74 +/- 14 cm.s-1 at a 90 degrees direction, 79 +/- 12 cm.s-1 at 180 degrees and 78 +/- 20 cm.s-1 at 270 degrees, where 0 degree was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P < 0.05) than during atrial pacing at the 90 degrees and 180 degrees directions but not compared to atrial pacing at 0 degree or 270 degrees. There was no significant difference in mean conduction velocity in different directions during atrial pacing. CONCLUSION: Although anisotropy was documented during conduction velocity in individual cases, conduction velocity was not dependent on propagation direction at the epicardial right atrial free wall in patients with stable sinus rhythm. These findings do not exclude the presence of internodal preferential pathways as these are located sub-epicardially and a marked transmural discordance in activation has previously been documented in the vicinity of such pathways.

  • Right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European heart journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    Aims Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. Methods and Results Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3×4cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolff–Parkinson–White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2·2 to 4·2cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomo-geneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88±9cm.s−1(mean±SD), ranging between 68±4 and 103±3cm.s−1during sinus rhythm. Mean conduction velocity during atrial pacing was 81±16cm.s−1at a propagation direction of 0°, 74±14cm.s−1at a 90° direction, 79±12cm.s−1at 180° and 78±20cm.s−1at 270°, where 0° was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P

Rolf Johansson - One of the best experts on this subject based on the ideXlab platform.

  • right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European Heart Journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    AIMS: Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. METHODS AND RESULTS: Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3 x 4 cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolf-Parkinson-White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2.2 to 4.2 cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomogeneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88 +/- 9 cm.s-1 (mean +/- SD), ranging between 68 +/- 4 and 103 +/- 3 cm.s-1 during sinus rhythm. Mean conduction velocity during atrial pacing was 81 +/- 16 cm.s-1 at a propagation direction of 0 degree, 74 +/- 14 cm.s-1 at a 90 degrees direction, 79 +/- 12 cm.s-1 at 180 degrees and 78 +/- 20 cm.s-1 at 270 degrees, where 0 degree was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P < 0.05) than during atrial pacing at the 90 degrees and 180 degrees directions but not compared to atrial pacing at 0 degree or 270 degrees. There was no significant difference in mean conduction velocity in different directions during atrial pacing. CONCLUSION: Although anisotropy was documented during conduction velocity in individual cases, conduction velocity was not dependent on propagation direction at the epicardial right atrial free wall in patients with stable sinus rhythm. These findings do not exclude the presence of internodal preferential pathways as these are located sub-epicardially and a marked transmural discordance in activation has previously been documented in the vicinity of such pathways.

  • Right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European heart journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    Aims Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. Methods and Results Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3×4cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolff–Parkinson–White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2·2 to 4·2cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomo-geneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88±9cm.s−1(mean±SD), ranging between 68±4 and 103±3cm.s−1during sinus rhythm. Mean conduction velocity during atrial pacing was 81±16cm.s−1at a propagation direction of 0°, 74±14cm.s−1at a 90° direction, 79±12cm.s−1at 180° and 78±20cm.s−1at 270°, where 0° was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P

Carsten Luhrs - One of the best experts on this subject based on the ideXlab platform.

  • right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European Heart Journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    AIMS: Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. METHODS AND RESULTS: Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3 x 4 cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolf-Parkinson-White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2.2 to 4.2 cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomogeneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88 +/- 9 cm.s-1 (mean +/- SD), ranging between 68 +/- 4 and 103 +/- 3 cm.s-1 during sinus rhythm. Mean conduction velocity during atrial pacing was 81 +/- 16 cm.s-1 at a propagation direction of 0 degree, 74 +/- 14 cm.s-1 at a 90 degrees direction, 79 +/- 12 cm.s-1 at 180 degrees and 78 +/- 20 cm.s-1 at 270 degrees, where 0 degree was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P < 0.05) than during atrial pacing at the 90 degrees and 180 degrees directions but not compared to atrial pacing at 0 degree or 270 degrees. There was no significant difference in mean conduction velocity in different directions during atrial pacing. CONCLUSION: Although anisotropy was documented during conduction velocity in individual cases, conduction velocity was not dependent on propagation direction at the epicardial right atrial free wall in patients with stable sinus rhythm. These findings do not exclude the presence of internodal preferential pathways as these are located sub-epicardially and a marked transmural discordance in activation has previously been documented in the vicinity of such pathways.

  • Right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European heart journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    Aims Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. Methods and Results Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3×4cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolff–Parkinson–White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2·2 to 4·2cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomo-geneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88±9cm.s−1(mean±SD), ranging between 68±4 and 103±3cm.s−1during sinus rhythm. Mean conduction velocity during atrial pacing was 81±16cm.s−1at a propagation direction of 0°, 74±14cm.s−1at a 90° direction, 79±12cm.s−1at 180° and 78±20cm.s−1at 270°, where 0° was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P

Per Blomström - One of the best experts on this subject based on the ideXlab platform.

  • right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European Heart Journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    AIMS: Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. METHODS AND RESULTS: Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3 x 4 cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolf-Parkinson-White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2.2 to 4.2 cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomogeneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88 +/- 9 cm.s-1 (mean +/- SD), ranging between 68 +/- 4 and 103 +/- 3 cm.s-1 during sinus rhythm. Mean conduction velocity during atrial pacing was 81 +/- 16 cm.s-1 at a propagation direction of 0 degree, 74 +/- 14 cm.s-1 at a 90 degrees direction, 79 +/- 12 cm.s-1 at 180 degrees and 78 +/- 20 cm.s-1 at 270 degrees, where 0 degree was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P < 0.05) than during atrial pacing at the 90 degrees and 180 degrees directions but not compared to atrial pacing at 0 degree or 270 degrees. There was no significant difference in mean conduction velocity in different directions during atrial pacing. CONCLUSION: Although anisotropy was documented during conduction velocity in individual cases, conduction velocity was not dependent on propagation direction at the epicardial right atrial free wall in patients with stable sinus rhythm. These findings do not exclude the presence of internodal preferential pathways as these are located sub-epicardially and a marked transmural discordance in activation has previously been documented in the vicinity of such pathways.

  • Right atrial free wall conduction velocity and degree of anisotropy in patients with stable sinus rhythm studied during open heart surgery
    European heart journal, 1998
    Co-Authors: A Hansson, Rolf Johansson, Carsten Luhrs, Per Blomström, Magnus Holm, Johan Brandt, S B Olsson
    Abstract:

    Aims Although the perpetuation of several supraventricular arrhythmias is critically dependent upon intra-atrial conduction, the literature lacks detailed information on normal values of conduction velocity and degree of anisotropy. In order to explore these factors further, we have measured conduction velocities at the right atrial free wall during sinus rhythm and during atrial pacing in four directions parallel and perpendicular to the atrioventricular groove in patients with normal atria and stable sinus rhythm. Methods and Results Using a Bard Cardiac Mapping System, atrial ECGs were recorded using a 3×4cm electrode array with 56 equally spaced bipolar electrodes in 12 patients undergoing open heart surgery due to ischaemic heart disease or Wolff–Parkinson–White syndrome. A bipolar pen probe connected to a Medtronic 5328 stimulator was used for pacing at a 10% higher rate than sinus rhythm. The local activation times were manually set and isochronal activation maps were created for each recording. The conduction velocities were calculated from the activation maps over a distance ranging from 2·2 to 4·2cm. The majority of the activation maps showed no signs of anisotropy; the others had less than 15% spatial inhomo-geneity of conduction. Mean conduction velocity, calculated from five consecutive beats, was 88±9cm.s−1(mean±SD), ranging between 68±4 and 103±3cm.s−1during sinus rhythm. Mean conduction velocity during atrial pacing was 81±16cm.s−1at a propagation direction of 0°, 74±14cm.s−1at a 90° direction, 79±12cm.s−1at 180° and 78±20cm.s−1at 270°, where 0° was parallel to the atrioventricular groove in the cranial direction and the angle increased counter-clockwise. Mean conduction velocity during sinus rhythm was significantly higher (P