(gentle instrumental music) - For patients that desire a cure or haven't had success with medications, an EP study with ablation
is often a good option. During our normal hearth rhythm, the electrical activity starts up in our natural pacemaker, the SA node. The SA node runs the show and sets our heart rate under normal circumstances. From there, the signal spreads through the two top chambers of
the heart, the atria. From the atria, the
signal is briefly held up for a split second in the AV node, which then spreads the
word to the two lower main pumping chambers of
the heart, the ventricles. One common form of SVT
called AV nodal reentrant tachycardia or AVNRT is when the AV node, the heart's natural electrical bridge between the top and bottom chambers, the atria and the
ventricles, has two pathways. It's like having two lanes to a road. This can lead to a short-circuit, where the electrical
activity keep spinning around up one pathway and down the other, each time spinning off a
heartbeat at a very fast rate. Another common form of SVT is called atrial ventricular reentrant
tachycardia or AVRT. In this rhythm, instead
of the AV node being the only electrical bridge between the top and bottom chambers of the heart, there can be an additional connection that can set up yet another
type of short-circuit where the signal goes down one connection, causes a heart beat, but instead
of the story ending there, the signal goes back
up the other connection and starts the cycle all over again. Yet another form of SVT is
called atrial tachycardia. This is where a small bit of tissue in the top chambers of
the heart, the atria, begins firing at a rapid rate. This then goes through the
AV node to the ventricles, causing a fast heart rate. During an EP study, you
are brought to the EP Lab in the hospital and given some sedation. You typically aren't completely under or on a breathing machine. Rather, we make you sleepy and comfortable so that you don't feel
or remember anything. Next, we place catheters
via the veins and sometimes the artery in the groins,
up into the heart. Using those catheters, we
actually pace the heart to try to flip it out of rhythm into SVT. Once we get the heart out
of rhythm into the SVT, we study the rhythm to
confirm the diagnosis. I want you to note that
a fraction of the time we can perform an EP study and not be able to get the heart out of rhythm. In that case, if we can't
get it out of rhythm, we typically can't perform any ablation. When we are successful at
getting the heart to go out of rhythm and identify
which type of SVT it is, we can often go on with the ablation. During ablation, we use a catheter that we follow with a 3D mapping system, like a GPS inside the heart, and bring the catheter
to the sight of entrance. We apply radio frequency
energy, which heats up and cauterizes the tissue,
burning the culprit; ideally, curing the rhythm problem. We will discuss the risks and benefits of your individual EP study and ablation with you in more detail in person. Each type of SVT has its own
set of risks and concerns; however, since we may
not know which of the rhythms you have until
we perform the study, we will discuss the risks
and concerns of all of them. (gentle instrumental music)
