Dragutin Novosel¹*, Petar Žuljević², Matija Alanović³, Robert Žunac⁴ and Tina Bečić⁵

¹Glaserbergstrasse 23, CH - 4056 Basel, Switzerland
²Ulica dr. Franje Tuđmana 8c, HR - 21220 Trogir, Croatia
³SIPA Elektronika d.o.o., Ruđera Boškovića 17, HR - 47000 Karlovac, Croatia
⁴Petra Kržića 8, HR - 47000 Karlovac, Croatia
⁵University of Split, Faculty of Medicine, Department of Cardiology, Spinčićeva 1, HR - 21000 Split, Croatia

*Corresponding Author: Dragutin Novosel, Glaserbergstrasse 23, CH - 4056 Basel, Switzerland.

Received: September 07, 2023; Published: September 29, 2023

Abstract

Background: A recently published paper argues that calculating the mean electrical axis of the heart in the frontal plane may lead to inaccuracies when using leads I (also known as lead D1) and aVF when the axis is within the range of -30° to 0° or between 90° and 110°.

Methods: Based on our previous reports we present counterarguments and demonstrate there is no compelling reason to avoid using the combination of leads I (D1) and aVF within these ranges.

Results: In cases where the value of aVF is negative and less than half (precisely 50.00%) of the value of I (D1), which is positive, the axis is between -30° and 0°. Similarly, when the value of I (D1) is negative and less than a third (precisely 31.52%) of the value of aVF, which is positive, the axis is between 90° and 110°. When both the I (D1) and aVF values are positive, the axis is between 0° and 90°. Therefore, we assert that there are no mathematical limitations preventing the use of leads I (D1) and aVF within the axis range of -30° to 110°.

Interpretation: In aligning with the currently valid criteria for the "normal axis values", which are for adults according to the American Heart Association between -30° and 90°, we described two rules to determine it as follows: (1) The value of the I (D1) is positive. (2) The value of the aVF is positive, or the value of the negative aVF is less than half the I (D1) value.

 Keywords: Electrical Heart Axis; Electrocardiography; Novosel Formula

References

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Citation

Citation: Dragutin Novosel., et al. “Simple Method to Determine the Normal Cardiac Axis with I (D1) and aVF”.Acta Scientific Medical Sciences 7.10 (2023): 86-88.

Copyright

Copyright: © 2023 Dragutin Novosel., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.