December 21, 2023

Disclaimer: This post was started on the 21st and not finished until later. Everything in here took place on Thursday, December 21st.

Today was clinic day – which means David had labs drawn, an echo, and then vitals and meeting with the cardiologist to go over questions, results, future planning, and any adjustments. We started off with lab. They tried unsuccessfully to draw blood from two locations before putting a call out to the vascular team. The vascular team’s main focus is hospital patients, so they will come as they have availability. In the mean time we went to echo.

Echo went fairly well. David started off sleeping but he woke up during it and stayed calm. It looked like he was trying to watch the images on the screen. Maybe he can explain to me what I’m looking at someday – I just know whatever is moving is his heart. 

After echo, we were shown our exam room where they did an EKG. David had the hiccups during this, so I’m not exactly sure if it turned out well or not. His doctor later was like “well, it’s not pretty, but it works”. During EKG a member of the cath team came in. She wanted to go over the cath procedure next week, and the different things we’ll have to do to prep for it, such as which medications to stop and when, same with eating, and things that could cause the procedure to be postponed. 

While I was talking with the cath nurse, we were informed that vascular was here, so we left the exam room and went back to lab. The vascular team uses an ultrasound machine to better locate a vein for the blood draw. The hope is that David will only need to be poked once. Although they were able to get to the vein with one poke, it still took a while for the blood to flow into the vial. In fact, David fell asleep during the process, and they had to keep moving the catheter they used to retrieve the blood in order to prevent a clot forming. They got the last bit of blood they needed right as the catheter exited his vein. 

Then it was back to the room, where we finished the conversation with the cath nurse and vitals checks before our team came in to discuss. I’ll do my best to summarize everything now. 

First thing I did was pull out a drawing of David’s heart to ask about the tricuspid valve issue and make sure I knew where it was leaking from. Before getting into that though, I think I’ll take a step back to explain the physiology of a normal heart because if I was not in this situation, I would have needed to look up a lot of the following terms. The heart is composed of 4 chambers: 

• Right Atrium – the right upper chamber of the heart. This is the chamber the oxygen deprived blood from the body goes into when it returns to the heart. From here the blood goes to the right ventricle by passing through the tricuspid valve. 
• Right Ventricle – the right lower chamber of the heart. The blood in this chamber gets pumped to the lungs via the pulmonary artery so the lungs can fill it with oxygen again. 
• Left Atrium – the left upper chamber of the heart. This chamber receives oxygen-rich blood from the lungs. From here it passes the blood the left ventricle via the mitral valve. 
• Left Ventricle – the left lower chamber of the heart. The blood in this chamber gets pumped to the body via the aorta.

Some unique features of David’s heart include: 

• Double Outlet Right Ventricle (DORV): Both the pulmonary artery and the aorta are attached to the right ventricle. 
• Hypoplastic Left Heart Syndrome (HLHS): His left ventricle is very tiny and under developed. Essentially whatever is there is non-functional. 
• Atrial Stent: This is a stent that is holding open a passage between his left and right atriums. They placed this stent shortly after birth via a cath procedure. First they had to create this opening since his was highly restrictive, and then the stent holds it open. This allows his right atrium to hold a mixture of oxygen deprived blood from his body along with oxygen rich blood from his left atrium. 
• Patent Ductus Arteriosus (PDA) Stent: Pre-birth, all babies have this opening that connects the pulmonary artery to the aorta. This allows the babies circulation to mostly skip the lungs prior to birth since the oxygen is supplied by the mother. It will typically close shortly after birth since it is no longer needed. David had a stent placed here shortly after birth via cath to keep it open. This will allow more blood to get into his aorta since the aortic valve and arch is so small otherwise, thus enabling more blood to be circulated to his body. 
• Pulmonary Artery (PA) Bands: These are bands placed around his pulmonary arteries that make those arteries a little more narrow so that the blood cannot travel through them so easily. This was placed via surgery when he was 2 days old. They tried putting flow restrictors within the pulmonary arteries via cath when he was first born, but David did not tolerate them well. Without these bands blood would flow too easily to the lungs and not much would go to the rest of David’s body. Now, when the blood leaves the right ventricle, it will be forced either to the pulmonary arteries or to his aorta (via the PDA stent). The bands just make getting to a lungs a little more difficult so that more blood will be forced to his body as well. Currently while he’s oversaturating, more blood than they would like is still going to his lungs versus the rest of his body, but as David grows this should get less and less since his arteries will get larger but the bands will not change size. 

So, now about the cath (catheterization) procedure David is scheduled to get next Wednesday. It’s a procedure that is less invasive than open heart surgery. They will find a vein in his groin area (if he has diaper rash, this could derail the day), and then use a catheter that will follow the vein up to his heart. With the catheter that day, the plan for that day is as follows: 

1. Measure more accurately the pressure variances on either side of his two stents. This should be fairly accurate since these measurements will take place directly in the heart. 
2. Balloon the atrial stent to reduce the pressure gradient that they are currently seeing
3. Check the pressures around the PDA stent. This should hopefully be close to zero (they do not expect 0 based on David’s heart physiology but no more than a 1 or 2). May balloon this stent as well if pressures are high but it is unknown if this will work since this stent is made of a different material that may not allow the size to change. It may go back to its current size. 

While David is sedated during this procedure, they will put an echo probe down David’s esophagus to get better photos of his heart and hopefully see that tricuspid valve with better detail. I learned that there have been some interesting discussions about that valve with various members on the cardiac team and the flow that is being seen – it’s something that appears no one has seen before (surprise surprise, David is rare once again). Basically, his cardiologist thinks his valve kind of looks like a figure-eight with a larger opening and a smaller opening. The smaller opening is always open, it never closes, but the larger one functions more like a valve. Therefore, the extra flow is occurring through that smaller opening. 

What does that mean? It’s all up to David on how his heart will be changed during future surgeries, but at the moment, they would still like to do the comprehensive stage 2 procedure in the future with now an added tricuspid valve repair as well. The surgeon actually said he can do that surgery at any time, it doesn’t matter David’s size. However, his cardiologist would prefer David to be bigger, especially with the additional features that David’s future surgery would entail, which now include: 

• The pulmonary artery bands will be removed
• The aortic arch will be repaired
• The tricuspid valve will be repaired
• The blood from the upper body will flow directly into the lungs (without going to the heart first). Now the right ventricle won’t have to work so hard. 

So after David’s cath procedure next Wednesday, we’re expecting him to spend a night in the hospital (CVICU) but then to be discharged the next day. For now, we’re trying to keep (actually get) David healthy. I think the older kids shared a cold with him so he has some nasal congestion and a cough. I’m hopeful it will be resolved by next week. Otherwise, he looks good. Talking with the team it sounds like they really don’t want to have to postpone this cath because they want to get those pressures reduced, and it would be a tough discussion next Tuesday if David still has symptoms. Of course, while I was trying to write this up, I got word that his cath may be next Tuesday due to scheduling- we’ll know by Monday so we will see.