R-wave progression or R-wave rotation? A 3D ECG-based perspective.

We applied a three-dimensional framework to the standard electrocardiogram and showed that conventional precordial deflections are discrete projections of a continuous spatial reference. Using only two leads and rotating this reference system, we tracked the morphological progression of QRS-T. In individuals without electrical abnormalities, spatial continuity was preserved with predominantly single, spheroidal loops, while right bundle branch block cases showed frequent disruptions. This method allowed tracking of deflections and notches, providing a geometric alternative to planar analysis for assessing R-wave progression, a parameter with clinical relevance due to its link with sudden cardiac death and other major cardiac conditions.