Sunday, January 2, 2011

The Cardiac Catheterization - Trying to Save Lillian's Heart

Like the Norwood surgery post, this post is intended primarily to explain what a cardiac catheterization is in general terms as well as explain how it went for Lillian. There will be a follow up post with the surgeon's notes later. As before, this will be much easier to follow if you've familiarized yourself with Lillian's heart condition, which you can read about here, as well as (to a lesser extent) her first surgery, which you can read about here.

A cardiac catheterization is a minimally invasive surgical procedure that allows the catherterization doctor/surgeon very clear views of the patient's heart and blood flow; in addition to allowing for other procedures like angioplasties. The way they are able to view the heart is by taking special X-rays called angiograms that allow extremely clear images of the heart. One such image is seen above. The procedure starts with surgeon inserting a guide wire into either the femoral artery (in the groin) or the radial artery (in the wrist). The surgeon then guides a plastic sheath over the guide wire and removes the guide wire once the sheath is in place. This sheath allows for the insertion of the cathether which is guided through the artery to the heart using another guide wire and X-rays. Once it reaches the intended location, the surgeon can inject special dye that is visible to X-rays or perform other procedures.

Lillian's cardiac catheterization was performed by Dr. Agustin Rubio (who really needs a higher resolution picture on Children's webpage...) on October 23rd. Since Lillian's veins and arteries are so small they used her left femoral artery as the entry point. Once the catheter was at her heart, Dr. Rubio performed a dye injection in her aorta to assess the state of her heart. One cool thing about the cath though is that it produces great pictures/videos. You can see the videos from this dye injection below.

A couple of notes about the videos - Youtube has compressed the picture quality so some of the really amazing detail is missing. If you're interested in seeing the videos in more detail, I have the full copies on my computer, and am willing to show them to other people. Regardless, I recommend watching it in the highest quality possible. The high quality video where you can see the dye flow in not only the major veins but the small ones as well is quite amazing. Also, the things you are seeing in the videos: the loops (there are 5 or 6 visible) are her stitches under her skin that keep her chest closed. The spring looking object (I believe) is the Sano shunt, and the two black lines I think are bands around the pulmonary arteries.

Start of Cath Dye Injection - Aorta - Front Profile 

Start of Cath Dye Injection - Aorta - Side Profile.

This dye injection revealed a severe coarctation (blockage) of Lillian's aorta near the end of where it tissue graft ended caused by scar tissue from the surgery. Even with the repair and expansion of the aorta done as good as it could be done, scar tissue is still an occurrence in about 15% of patients who get a Norwood procedure. The scar tissue left only an opening of 2.9mm in diameter, when her normal aorta ranged from 5mm to 10mm. Pumping blood past this blockage was likely the cause of the heart distress, so the doctors decided to perform a balloon angioplasty of the blockage to remove it. 

Aortic Angioplasty - Front Profile

Aortic Angioplasty - Side Profile

The blockage in the aorta was pretty severe, and Dr. Rubio was only able to do one angioplasty. Even that angioplasty caused her to code briefly, and it was not worth the risk to do a second one to be sure. Once the angioplasty was completed, Dr. Rubio and his team did more dye injections to assess function after the blockage was cleared. The videos for those injections are below. 
Post Angioplasty Aortic Dye Injection - Front Profile

Post Angioplasty Aortic Dye Injection - Side Profile 

These next two videos are probably the most interesting ones. This dye injection was directly into Lillian's right ventricle, the one pumping chamber she has in her heart. This video really shows the branching veins of her circulatory system; but more importantly how poor her heart function is. You'll notice in these videos that Lillian's heart takes quite a few beats to clear the dye. 

Post Angioplasty Ventricle Dye Injection - Front Profile

Post Angioplasty Ventricle Dye Injection - Side Profile

At this point another dye injection was done to see how the blood flow looked a little while loner after the angioplasty. These two videos are strikingly similar to the other two videos labeled as Aortic Dye Injections, but these videos are so interesting that I'm including all of them. 

Post Angioplasty Aortic Dye Injection #2 - Front Profile

Post Angioplasty Aortic Dye Injection #2 - Side Profile

At this point the cath was finished so Lillian was woken up and sent to the Cardiac Intensive Care Unit for care. The cath was an extremely valuable procedure to do as it told us things about Lillian's heart that we had never been able to see or tell before, even during open heart surgery. The cath showed us the blockage of her aorta that we had never been able to see via ECHO. The blockage was so bad and her heart was in such distress that she probably would have not made it through the weekend without the angioplasty.

Perhaps the most significant thing the cath has told us, or at least confirmed, is that Lillian has a single coronary physiology. In English: we all have two coronary arteries which are the blood vessels that feed the heart directly. Lillian has only one coronary artery that we can see. Technically, she does have a second one, but we see no blood flow through this so it's existence is negligible. The one she does have is small and mutated, traveling down the right side of the heart as we would expect before branching and traveling back up the left side, which we would not expect. And even though Lillian doesn't use the left side of her heart, it is still a living muscle and needs to be given blood. Without the heart getting enough blood itself, it is unable to pump enough blood to the rest of Lillian's body. This is the real cause of the symptom that caused us to notice the heart failure; as since her stomach wasn't getting enough blood, it wasn't able to digest food properly and Lillian didn't eat. 

Our hope at this point was that with Milrinone therapy, Lillian would recover enough heart function to continue along the surgical track, but that insight would only come with time.

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