The following is a summary of “Anatomical cardiac and electrocardiographic axes correlate in both upright and supine positions: an upright/supine CT study,” published in the October 2023 issue of Cardiology by Norimatsu et al. 

The correlation between cardiac and electrocardiography (ECG) axes has been debated for years. Researchers performed a retrospective study to investigate the relationship between cardiac and ECG axes in supine and upright positions. 

This study included 41 male volunteers out of a total of 190. Healthy volunteers underwent both upright and standard supine CT scans following ECG in both positions. The CT images recorded the coordinates of the apex, the center of the aortic valve (AV), and the mitral valvye (MV). They calculated vectors and angles. Subcutaneous and visceral fat volumes were semi-automatically calculated using a workstation. 

There was a significant correlation between the QRS and anatomical axes (AV-apex and MV-apex axis) in both supine and upright positions. The most correlated angle was the AV-apex to the Z-axis (supine: r = −0.54, P= 0.0002, upright: r = −0.47, P= 0.0020). The anatomical axis shifted towards the dorsal and caudal directions from supine to upright position. Multiple regression analysis indicated that the AV-apex to Z-axis anatomical axis was influenced by age, body height, and subcutaneous and visceral fat volumes.

Source: nature.com/articles/s41598-023-45528-y