The vectorcardiogram of the newborn infant

Cardiodynamic Studies in the Neonate in Health and in Disease

“…T he re su lts o f th e v ecto rial analysis o f the electro card io g ram of th e h e a lth y new b o rn in fa n ts re p o rte d in th is stu d y arc in ag reem en t w ith th e q u a lita tiv e a n d q u a n tita tiv e d a ta re p o rte d b y oth ers (9,10,11,12,13,14). T h e re is an a p p a re n t d iscrepancy betw een o u r values for th e d irectio n o f th e m ean v e c to r of Q R S and th e Q R S -T angle and th o se p ublished b y Rothfeld and coworkers (15).…”

“…T h e effect o f p re m a tu rity on th e electro card io g ram has been well d o cu m en ted in several stu d ies, p a rtic u la rly those o f Salm i and co-workers (7) a n d o f Ilubsher (8). T he use o f d ire c t v ecto rcard io g ra p h y in th e e v a lu a tio n o f th e card iac dynam ics o f th e n eo n ate has been s tu d ie d b y a n u m b e r o f a u th o rs (9,10,11,12,13,14,15). T he m a jo rity o f th e se com m u n icatio n s describe the d irectio n a n d shape of th e loops o f th e Q R S an d T in several planes, b u t th e lim ita tio n s of th e te c h n iq u e p reclude a co n c o m ita n t q u a n tita tiv e analysis o f o th e r co m p o n en ts o f th e electro card io g ram , i.e., v ecto r o f P a n d th e scalar m ag n itu d es.…”

Orientation of the electrical heart axis in mid-term pregnancy

“…In term fetuses during labor, the main direction of the fetal heart axis is to the right (between +100 and +1608) [12]. In neonates directly postpartum, the QRS-axis in the frontal view varies between +60 and +1608 and the vectorcardiogram points mainly to the rightinferior-anterior direction [2,13,14]. As the mass of the left ventricle increases with age, the orientation of the electrical heart axis gradually deviates toward the left.…”

The electrical heart axis and ST events in fetal monitoring: A post-hoc analysis following a multicentre randomised controlled trial

“…Similar inter-person variation in the orientation of the electrical heart axis is present in neonates and adults [24–27]. The STAN monitor attempts to correct for the orientation of the electrical heart axis with the first step in its protocol (normalisation).…”