Results:
Triggers
In patients with CAD the mean coupling interval (CI) between the
extrastimuli and PVC1 (S-PVC1) was 237±75 ms and between PVC1- PVC2:
212±70 ms. The duration of QRS: PVC 1 187± 35 ms and PVC2 189±32 ms. In
patients with BS, SPVC1: 277± 50 ms; PVC1-PVC2: 217± 28 ms; QRS duration
PVC 1: 207± 32 ms; PVC2: 186± 33 ms. (Fig 1). Four QRS morphologies were
observed : similar to stimulated QRS (IR); LBBB with late transition and
superior axis; RBBB with superior left axis and LBBB with inferior axis.
These morphologies appear both in PVC1 and PVC2. In Brugada Syndrome
cases, the predominant morphologies were those with LBBB morphology, and
in CAD cases, those with RBBB morphology predominated (Fig 1)
Tachysistolic stage
In this first phase, QRS morphologies are still observed, unlike the
following phase where only sinusoidal waves can be seen. In the group
with coronary arterial disease there is a predominant morphology with
right bundle branch and superior axis. (Fig 2,3). In the Brugada
Syndrome group, RBBB and superior axis morphologies are not
distinguished; on the contrary, LBBB and inferior axis morphologies are
predominant, together with others which are less common with LBBB and
superior axis morphologies (Fig 4).
Sinusoidal stage
The phase after what we call tachysistolic, is characterized by
sinusoidal complexes, where we can no longer distinguish QRS, which
following Wigger´s description could correspond to Wigger´s convulsive
incoordination phase. If we analyze this portion of the ECG we can
distinguish complexes of great amplitude and others of smaller amplitude
with notches; established VF is characterized by sinusoidal complexes
with large amplitude and traces with an appearance of notches. These
should not be confused with the final phase of VF where there are only
low amplitude waves corresponding to a phase of disorganization. Notches
in the sinusoidal complexes appeared in sustained VF, but not in
non-sustained VF (Fig 5).