 Now let's go back and talk a little bit more about poor chamber view abnormalities. This is the paper I mentioned earlier ago a few years ago in the United States looking at percentage of cases of major heart disease that are detected before birth and as I mentioned earlier even an AV canal defect more likely than not to where we in the United States have been missing AV canal defects, which is a typical classic four chamber view abnormality that everything else would be normal and still we're missing those. So we really need to get better at evaluating the four chamber view and identifying abnormalities on the four chamber view. It's not just that we need to work on the outflow tracks, we need to be better at looking at abnormalities of the four chamber view. And again what we talked about up to this point is the key I think is to obtain really high quality four chamber views and look at all the elements within the four chamber view in normals getting in used to doing that on every single heart. And the four chamber view really should be thinking in terms of four chamber views plural multiple views because seeing the mitral valve you may require a different angle than seeing the tricuspid valve. And of course if we want to look at these valves we can do so parallel but if we want to look at the septum we want to be more perpendicular. If we want to look at valvoregurage we do it from here. So let's start by looking at probably the most common four chamber view abnormality is besides an echogenic focus of course is an in-let or muscular ventricular septal defect. And I showed you this before that the concept that you want to be perpendicular not parallel and that applies both for 2D and for COER. You want to be perpendicular to the septum. This is my favorite view with the LV on the bottom. Perpendicular to see the septum really well. And then here in this case you need COER to be perpendicular too because we're missing it in this clip but we see it over here. Very common defect picking up muscular ventricular septal defects. There's some more examples. This one you could see it's quite large. It's not the absolute number that I think about when someone I want to look at how big it is compared to the erotic valve annulus. This is about the same size. The VSD is greater than half the size of the erotic valve annulus. That's a significant defect. So this is a large muscular ventricular septal defect. This one's much smaller. This one's much smaller. You could see the shunting also is useful. This is shunting from RV to LV. This is shunting that's bi-directional. Sometimes we see left to right shunting. Sometimes bi-directional. It's unusual just to have pure right to left shunt. When we see that prenatally we need to think is there some sort of right ventricular alfotract obstruction, ductile constriction, pulmonary stenosis. Some reason why the shunting direction is right to left. This is something very important. This patient, believe it or not, these all come from the same patient from the same scan. This was a baby, the mother had diabetes, so I was scanning this mom for the maternal diabetes. This looked pretty normal to me. This looked pretty normal, but we're not seeing the apex. Look what's down in the apex. Big VSD. So the key is sometimes, as I mentioned earlier, the apex sometimes is very hard to open up, but there's a lot of times that we'll see muscular VSDs at the apex. Even after birth, sometimes we miss apical ventricular septal defects if we don't spend extra time looking at them. For you to know from a clinical stamp, a small muscular ventricular septal defect is very unlikely to ever require surgery or medicine. These defects close on their own within the first few years after birth, sometimes even before birth. But if you see a ventricular septal defect, there's probably an increased likelihood in that fetus for other cardiac abnormalities. So it deserves careful fetal echocardiographic evaluation. And there may be a potential for genetic abnormality as well, even though the likelihood for genetic abnormality for a muscular VSD is much less than for an AV canal, say, or a tetralogy of fallot. But increasingly in our practice, we do talk about the possibility for genetic abnormality. And if an amnia is done, then we send for a microarray. But that's our practice. But in general, for the clinical outlook is very good. And these VSDs, unless they're quite big, if they're big, then sometimes we need to do... They can develop overcirculation. They start to breathe fast. Babies may not gain weight. They may need medicine for a while. And sometimes we need to do surgery to close them. Sometimes we put a pulmonary artery band initially to get them bigger before we go and bypass to close. But in general, they're very benign. This is just to make sure everyone's aware. This is the four chamber view portion of the ventricular septum. This is the inlet septum here. You could see the mitral valve and the tricessa valve being offset. This is the atrial ventricular septum. And this is the rest, all muscular septum. So this is all four chamber view portion of the septum. Now here, this is outlet septum because we see the erotic valve. And here you could see a small VSD in the membranous septum. So this is not really a four chamber view abnormality. This is the outlet septum.