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On recording the unipolar ECG limb leads via the Wilson's vs the Goldberger's terminals: aVR, aVL, and aVF revisited.

Madias JE - Indian Pacing Electrophysiol J (2008)

View Article: PubMed Central - PubMed

Affiliation: Mount Sinai School of Medicine of the New York University, and the Division of Cardiology, Elmhurst Hospital Center, New York, NY, USA. madiasj@nychhc.org

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The augmented unipolar limb leads aVR, aVL, and aVF, introduced by Goldberger in 1942, are an integral part of the 12-lead ECG... This modification of Goldberger leads to the augmentation of the recorded limb leads by 50%, as can be shown mathematically, and thus the aVR, aVL, and aVF came into being... The WCT does not represent a zero potential, since it is ~0.3 mV ; also GCT carries not a zero potential since the high resistances at the skin-electrode interfaces are not equal... The standard ECG consists of 3 different sets of leads: the bipolar leads I, II, and II, the unipolar V1-V6 leads recorded via the stable WCT, and the unipolar aVR, aVL, and aVF leads recorded via the changing GCT... The aberration is that the last are augmented, are acquired via a thrice changing terminal, and a different one, than the WCT... A particular heart's zero potential, also by itself constantly changing in 3D space, must be one, and thus having both the WCT and GCT used does not appear theoretically appealing... Accordingly a 9-unipolar lead ECG consisting of the V1-V6 leads, and the 3 unipolar limb leads, obtained via the WCT would suffice... The bipolar leads I, II, and III do not belong in such an idealized schema, but their historic importance, and their association with so many useful applications, supports their retention; nevertheless these leads can be supplanted by the 3 unipolar limb leads with impunity... Moreover manual measurements (thought by some to be the gold standard) on enlarged ECG tracings can be done on a computer screen or electronic reading tablet (in cases of scanned ECG hardcopies), with reader-operated electronic cursors... Finally the possible concern that the familiarity of physicians with aVR/aVL/aVF will not be maintained with the substitution of these leads by VR/VL/VF recorded via the WCT is unfounded, since the latter have similar morphologies to the former. (Figure 2 and 3)... But what would be the advantages of a substitution of the GCT with the WCT for recording the 3 unipolar limb leads? This would result in: Uniformity in the recording of unipolar limb and precordial leads... When e.g., an ECG showing a lateral MI is evaluated with ST-segment deviations involving the lateral precordial leads and aVL, one should constantly factor in that the amplitude of ST-segment deviation in aVL is augmented by 50%... The underlying notion of the above arguments is that when employing quantitative ECG, one theoretically should not use in the calculation of sums measurements from leads that are not augmented (i.e., V1-V6) with leads that are augmented (i.e., aVR, aVL, and aVF)... Perhaps a starting point can be that when summation of ECG potentials is used in practice or research, the values from aVR/aVL/aVF leads should be multiplied by 2/3 before proceeding with summation with the values from V1-V6 leads, since the limb and precordial leads have not been recorded against the same reference point.

No MeSH data available.


The column with leads VR, VL, and VF, recorded via the Wilson's terminal in the 2nd ECG, has been superimposed on the 1st ECG to aid in the comparison of leads VR, VL, and VF with aVR, aVL, and aVF.
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Figure 2: The column with leads VR, VL, and VF, recorded via the Wilson's terminal in the 2nd ECG, has been superimposed on the 1st ECG to aid in the comparison of leads VR, VL, and VF with aVR, aVL, and aVF.

Mentions: Is this augmentation of any use, or we can go back [11] to acquiring the unipolar limb leads via the WCT? An ECG (Figure 2) was routinely recorded, and immediately repeated at the same calibration with the V1, V2, and V3 leads connected to the right arm, left arm and left leg, respectively. The V1, V2 and V3 of the 2nd ECG included now the leads VR, VL, and VF, recorded via the WCT; the morphology of the unipolar limb leads in both ECGs is the same, but their amplitude in the 2nd ECG, is attenuated by ~1/3.


On recording the unipolar ECG limb leads via the Wilson's vs the Goldberger's terminals: aVR, aVL, and aVF revisited.

Madias JE - Indian Pacing Electrophysiol J (2008)

The column with leads VR, VL, and VF, recorded via the Wilson's terminal in the 2nd ECG, has been superimposed on the 1st ECG to aid in the comparison of leads VR, VL, and VF with aVR, aVL, and aVF.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2572021&req=5

Figure 2: The column with leads VR, VL, and VF, recorded via the Wilson's terminal in the 2nd ECG, has been superimposed on the 1st ECG to aid in the comparison of leads VR, VL, and VF with aVR, aVL, and aVF.
Mentions: Is this augmentation of any use, or we can go back [11] to acquiring the unipolar limb leads via the WCT? An ECG (Figure 2) was routinely recorded, and immediately repeated at the same calibration with the V1, V2, and V3 leads connected to the right arm, left arm and left leg, respectively. The V1, V2 and V3 of the 2nd ECG included now the leads VR, VL, and VF, recorded via the WCT; the morphology of the unipolar limb leads in both ECGs is the same, but their amplitude in the 2nd ECG, is attenuated by ~1/3.

View Article: PubMed Central - PubMed

Affiliation: Mount Sinai School of Medicine of the New York University, and the Division of Cardiology, Elmhurst Hospital Center, New York, NY, USA. madiasj@nychhc.org

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

The augmented unipolar limb leads aVR, aVL, and aVF, introduced by Goldberger in 1942, are an integral part of the 12-lead ECG... This modification of Goldberger leads to the augmentation of the recorded limb leads by 50%, as can be shown mathematically, and thus the aVR, aVL, and aVF came into being... The WCT does not represent a zero potential, since it is ~0.3 mV ; also GCT carries not a zero potential since the high resistances at the skin-electrode interfaces are not equal... The standard ECG consists of 3 different sets of leads: the bipolar leads I, II, and II, the unipolar V1-V6 leads recorded via the stable WCT, and the unipolar aVR, aVL, and aVF leads recorded via the changing GCT... The aberration is that the last are augmented, are acquired via a thrice changing terminal, and a different one, than the WCT... A particular heart's zero potential, also by itself constantly changing in 3D space, must be one, and thus having both the WCT and GCT used does not appear theoretically appealing... Accordingly a 9-unipolar lead ECG consisting of the V1-V6 leads, and the 3 unipolar limb leads, obtained via the WCT would suffice... The bipolar leads I, II, and III do not belong in such an idealized schema, but their historic importance, and their association with so many useful applications, supports their retention; nevertheless these leads can be supplanted by the 3 unipolar limb leads with impunity... Moreover manual measurements (thought by some to be the gold standard) on enlarged ECG tracings can be done on a computer screen or electronic reading tablet (in cases of scanned ECG hardcopies), with reader-operated electronic cursors... Finally the possible concern that the familiarity of physicians with aVR/aVL/aVF will not be maintained with the substitution of these leads by VR/VL/VF recorded via the WCT is unfounded, since the latter have similar morphologies to the former. (Figure 2 and 3)... But what would be the advantages of a substitution of the GCT with the WCT for recording the 3 unipolar limb leads? This would result in: Uniformity in the recording of unipolar limb and precordial leads... When e.g., an ECG showing a lateral MI is evaluated with ST-segment deviations involving the lateral precordial leads and aVL, one should constantly factor in that the amplitude of ST-segment deviation in aVL is augmented by 50%... The underlying notion of the above arguments is that when employing quantitative ECG, one theoretically should not use in the calculation of sums measurements from leads that are not augmented (i.e., V1-V6) with leads that are augmented (i.e., aVR, aVL, and aVF)... Perhaps a starting point can be that when summation of ECG potentials is used in practice or research, the values from aVR/aVL/aVF leads should be multiplied by 2/3 before proceeding with summation with the values from V1-V6 leads, since the limb and precordial leads have not been recorded against the same reference point.

No MeSH data available.