<s>
All	O
three	O
presentations	O
allow	O
distinct	O
and	O
easily	O
reproducible	O
electrical	O
signatures	O
as	O
illustrated	O
by	O
left	O
and	O
right	O
bundle	B-Algorithm
branch	I-Algorithm
blocks	I-Algorithm
,	O
hemiblocks	O
,	O
etc	O
.	O
</s>
<s>
Echocardiography	B-Application
and	O
tissue	O
Doppler	O
echocardiography	B-Application
are	O
both	O
needed	O
to	O
fully	O
diagnose	O
the	O
different	O
types	O
of	O
ventricular	O
dyssynchrony	O
.	O
</s>
<s>
Recent	O
studies	O
suggest	O
that	O
cardiac	B-Algorithm
resynchronization	I-Algorithm
therapy	I-Algorithm
can	O
reduce	O
the	O
incidence	O
of	O
ventricular	O
dyssynchrony	O
and	O
thus	O
increase	O
cardiac	O
efficiency	O
.	O
</s>
