0:00

In this next case, we're going to review a left dominant coronary

0:03

circulation. Now, you'll notice that the images are

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a bit noisier in this case because this is actually a

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larger patient when you have large patients, sometimes

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they'll get some image noise that'll limit your evaluation of

0:15

the small branches.

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But in this case we can still see the main branches quite well

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and and some of the larger branches.

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Having said all that when we have a left dominant circulation

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what we expect to see is a really

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good size LED as well as a good

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size. Circumflex Branch so you can see here nice very

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easily visualized LED coming

0:37

off the left Main and a nice good sized circumflex.

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Now remember the branches of the LED are called diagonal

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branches so you can see one here.

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And then as the LED heads down towards the Apex you can

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see a tapers.

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And then you really don't see it very well very distally that's

0:55

normal from the circle Flex. The branches are

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called the obtuse marginal branches in this particular patient. You can

1:01

see there's an early branching obtuse marginal right here, which is

1:04

moderate in size. And then as we

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head down further following the circumflex down you can

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see that it stays quite large even moving down into the

1:13

mid 80 Groove and Beyond which is suggestive of a

1:16

left dominant circulation. Usually the circumflex is not quite that big

1:19

You can see this Branch here. So now we have two branches. This

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is an obtuse marginal branch, which is heading down

1:25

over the lateral slash in for a

1:28

lateral region of the LV.

1:32

And then as we go further you can see that the circumflex becomes

1:35

the PDA here.

1:38

Oftentimes also see some smaller branches off

1:41

the circumflex that are the posterolateral branches

1:44

in this case. I don't really see one very clearly. Maybe this

1:47

tiny little dot right here, maybe a little poster lateral

1:50

Branch as well. That's something you typically might

1:53

see for a left dominant circulation. The other

1:56

thing that you find it's a clue for left dominant circulation is that there

1:59

are sea tends to be small. You can see here. It's a

2:02

small maybe moderate size vessel and a

2:05

lot of times it'll go into the EV Groove

2:08

give off an acute marginal and then kind of just Peter out

2:11

so that you really don't even see it hardly at all

2:14

one by the time you get into the distal AV Groove region along

2:17

the heart again another clue that

2:20

you're dealing with the left dominant circulation.

2:24

now one thing I want to point out with this left dominant circulation is that

2:28

looking at the

2:30

obvious marginal branches with these two chamber sort

2:33

of sagittal two chamber reconstructions can be really helpful.

2:37

So let me just review that real quick. Here's the two chamber view.

2:40

We're going to scroll over and follow this circumflex laterally.

2:45

And then we can see this obtuse marginal Branch coming over

2:48

here along the side of the heart.

2:51

So using these lateral views can be really helpful to

2:54

assess these branches that sometimes don't

2:57

get followed completely by the curved planar

3:00

reconstruction images.

3:02

So that's one sort of helpful thing

3:05

to do, especially when you're dealing with patients who have

3:08

a left dominant system.