<s>
Defibrillation	B-Algorithm
threshold	I-Algorithm
indicates	O
the	O
minimum	O
amount	O
of	O
energy	O
needed	O
to	O
return	O
normal	O
rhythm	O
to	O
a	O
heart	O
that	O
is	O
beating	O
in	O
a	O
cardiac	B-Application
dysrhythmia	I-Application
.	O
</s>
<s>
Typical	O
examples	O
are	O
the	O
minimum	O
amount	O
of	O
energy	O
,	O
expressed	O
in	O
joules	B-Language
,	O
delivered	O
by	O
external	O
defibrillator	O
paddles	O
or	O
pads	O
,	O
required	O
to	O
break	O
atrial	B-Application
fibrillation	I-Application
and	O
restore	O
normal	O
sinus	O
rhythm	O
.	O
</s>
<s>
Other	O
common	O
scenarios	O
are	O
restoring	O
normal	O
rhythm	O
from	O
atrial	O
flutter	O
,	O
ventricular	B-Application
tachycardia	I-Application
or	O
ventricular	O
fibrillation	O
.	O
</s>
<s>
The	O
defibrillation	B-Algorithm
threshold	I-Algorithm
ranking	O
in	O
these	O
settings	O
,	O
from	O
lowest	O
to	O
highest	O
,	O
would	O
be	O
,	O
in	O
order	O
,	O
ventricular	B-Application
tachycardia	I-Application
,	O
atrial	O
flutter	O
,	O
atrial	B-Application
fibrillation	I-Application
,	O
ventricular	O
fibrillation	O
.	O
</s>
<s>
The	O
highest	O
amount	O
of	O
energy	O
that	O
an	O
external	O
defibrillator	O
can	O
deliver	O
at	O
the	O
present	O
time	O
is	O
360	O
joules	B-Language
biphasic	O
.	O
</s>
<s>
Defibrillation	B-Algorithm
threshold	I-Algorithm
is	O
a	O
concept	O
also	O
applicable	O
to	O
internal	O
or	O
implantable	O
cardiac	O
defibrillators	O
.	O
</s>
<s>
The	O
test	O
needed	O
to	O
establish	O
the	O
defibrillation	B-Algorithm
threshold	I-Algorithm
is	O
often	O
referred	O
to	O
as	O
DFT	O
.	O
</s>
