BACKGROUND: Lillian is a 3-month-old female who was born with complex congenital heart disease consisting of hypoplastic left heart syndrome (AAMA type). She also carries a diagnosis of a single right coronary artery [see paragraph 7 under the heading Lillian's Norwood Procedure on this post]. She has undergone a Norwood palliation and placement of a Sano shunt. Over the course of the past several weeks, she has been noted on echocardiogram to have a change in her right ventricular function as well as worsening atrioventricular valvar insufficiency [the valve is leaking, specifically, this is the tricuspid valve (between the right atrium and right ventricle), as Lillian's mitral valve is nonexistent as a side effect of the HLHS]. Her saturations continue to be rather elevated of 85-90% on room air [as Lillian is a mixer, we would want her to be 75-85% on room air]. She has been referred to the Cardiac Catheterization Laboratory due to echocardiographic findings which have not been able to adequately evaluate the distal Norwood anastomosis [we can't see the site of the tissue graft on her aorta very well]. With the evidence of decreased right ventricular function, worsening atrioventricular valvar insufficiency and elevated saturations, the suspicion is that there may be significant obstruction of the distal Norwood.
PROCEDURE/INDICATION: Right and left cardiac catheterization with possible balloon angioplasty [a balloon angioplasty is when they inflate a balloon in a blood vessel to clear a blockage] of the distal aortic arch for possible arch obstruction.
PROCEDURE: The patient's parents underwent informed consent prior to the patient coming to the Cardiac Catheterization Laboratory. The patient was brought to the Cardiac Catheterization Laboratory by Dr. Michael Richards. The patient was placed on the cardiac catheterization table and underwent appropriate sedation, analgesia [pain medicine] and securing of hemodynamic monitoring [very specific blood pressure monitoring in several different vessels].
Once the patient was sedated and adequately monitored, the patient was intubated [all infants are intubated when they are put under to reduce the risk of the lungs collapsing] and placed on room air. The patient was prepped and draped in a typical sterile fashion and 2 mL of 1% lidocaine [local anesthetic] was administered subcutaneously [i.e., a shot] into the right groin. The right femoral artery was easily accessed with a 3-French arterial catheter as was the right femoral vein and a 5-French sheath [this basically is the size of what they used] was easily placed via Seldinger technique. A 5-French wedge catheter was utilized to obtain all of the hemodynamic data throughout the right heart and left heart structures as well as into the descending aorta [basically they took measurements of all her information before doing anything else]. An 0.025 angled Glidewire was utilized to obtain a pressure beyond the distal Norwood [checking blood pressure after the location of the potential blockage]. At the time of crossing the distal arch over the wire, a severe change in right ventricular function with severe drop in blood pressure was noted. It is for that reason that the Glidecath was emergently removed and a dose of epinephrine was administered. The patient was allowed to recover prior to any further interventions occurring. [I'm not really sure why this occurred. It is possible that the Glidecath filled the vessel entirely blocking the ventricle from pumping blood and thus resulting in the blood pressure drop. I don't entirely see how this is possible though due to how small the cath is. Regardless, they gave her adrenaline, so it was enough of a concern for that relatively drastic measure.]
After the patient had her blood pressure recovered, she had 485 unites of intravenous heparin administered [a blood thinner to make sure the catheters don't cause any issues]. An angiogram [this is the X-ray videos that along with fluoroscopy allow us to have a high quality view of Lillian's blood flow] was performed via the 4 Fr angle Glide cath. A severe caliber change was noted at the distal anastomosis of the Norwood [sudden narrowing, this confirms the previously suspected blockage]. The measurement obtained revealed: 2.9mm diameter (by AP and Lat), descending aorta 5mm and 10mm (aorta proximal to arch obstruction) [this is already pretty clear, but just to emphasize, her aorta is normally between 5mm and 10mm, so only having 2.9mm open at one point is severe] The 4 Fr catheter allowed for passage of an 0.014 Hi-Torque guide-wire. The wire easily passed through the distal area of narrowing [they got through the blockage with a very thin wire]. The proximal portions of the Norwood anastomosis appeared to be widely patent as do the head and neck vessels [other than the one blockage, the rest of the Norwood tissue graft looks fine, and the vessels to her head and neck are wide open; these vessels do present something of concern in many Norwood cases, so it is good that this is open for Lillian].
The decision was made to perform a balloon angioplasty using a 6mm Tyshak II balloon dilatation catheter [this is the procedure that was speculated as being needed at the start, this will clear the blockage]. The 4 Fr Glide catheter was removed and the balloon dilation catheter was passed in prograde fashion through the narrowed segment. The balloon was quickly dilated to maximum ATM's and the[n] quickly deflated. At full inflation a very small waist [I'm not entirely sure as to what this means, but from my understanding this means that there was a tiny bit of blood flow around the balloon on the front projection. There should normally be no blood flow when the balloon is fully inflated.] was noted in the AP projection but no waist appreciated in the lateral projection. A follow-up ascending angiogram was performed which demonstrated a moderate improvement with a small degree of neointimal disruption appreciated without extravasation of contrast [the follow up angiogram shows an improvement, and although there is still a small blockage in the artery, it does nothing to the contrast, and thus will not do anything to the normal blood flow]. Improved flow of contrast through the distal transverse arch is noted with a significant improvement in the right femoral arterial pressure [the clearing is making it easier for her heart to pump blood to her extremities].
Given the significant concern for decreased myocardial function secondary to distal arch obstruction [even with clearing the blockage, they were concerned that her heart muscle would not be functioning well enough], it was felt after discussions with the cardiac intensivists and with the Heart Failure Team that Lillian would do best by being transferred to the Cardiac Intensive Care Unit with a central venous catheter and an arterial line [these allow for central medication delivery and continuous blood pressure monitoring].
Upon completion of the hemodynamic and angiographic assessment and interventional aspect of the procedure, the 5-French venous catheter was switched out for the 5-French double-lumen central venous catheter. The 3-French right femoral arterial line was kept in place.
Lillian was extubated and awoke and transferred to the Cardiac Intensive Care Unit for further medical management.
COMPLICATIONS: None.
FLUOROSCOPIC TIME: 16.7 Minutes.
CONTRAST: A total of 21 mL of Optiray contrast was administered.
I performed all aspects of the above-mentioned procedure.
RESULTS:
1. CATHETER COURSE: The catheter coursed normally through the intracardiac chambers of a hypoplastic left heart syndrome and into the left upper and right upper pulmonary veins. Distal arch was accessed in antegrade fashion [they went with the flow of blood rather than against it]
2. OXIMETRIES: The mixed venous oxygen saturation was 48% with a right atrial saturation of 69%. The systemic arterial saturation was 88% with a descending aortic saturation of 88%. The right ventricular saturation was 88%. The left upper and right upper pulmonary vein saturations were 97% with a left atrial saturation of 97%. [to clear up exactly what he's talking about: mixed venous refers to how she mixes both oxygenated and unoxygenated blood; her right atrium is the main collection chamber for blood before it is pumped, systemic refers to the part of the circulatory system that sends oxygenated blood to the body; the descending aorta delivers that oxygenated blood to the lower portions of the body; the right ventricle is her one and only pumping chamber, so should have higher saturations; pulmonary refers to the lungs so these of course should have the highest saturations; he also measures the left atrial saturation at 97%, this is expected as the left side of the heart would normally pump the oxygen rich blood, but she does not have a left ventricle to pump that blood so that chamber serves basically as a collection chamber supplementing the right one that she does have].
3. PRESSURES: The mean SVC pressure was 9mmHg. The mean right atrial pressure 9 mmHg. The mean left atrial pressure was 10 mmHg with a right ventricular pressure of 61/10. The ascending aortic pressure proximal to the area of stenosis [by the narrowing that was cleared] was 60/32 with a mean of 42 mmHg with a descending arterial pressure of 55/32 with a mean of 40 mmHg. Right and left upper pulmonary veins had mean venous pressures of 9 mmHg. The right branch pulmonary arterial pressure by pulmonary vein wedge pressure was 19/12 with a mean of 15 mmHg. The left branch pulmonary arterial pressure was estimated via pulmonary vein wedge pressure of 20/13 with a mean of 16 mmHg. Her PVR was estimated at 1.23 Woods units x m2 with a Qp/Qs of 1.13/1 [see my comment on the oximetries section for an explanation of where these are being measured; the PVR is pulmonary vascular resistance, this is what the blood must overcome to flow to the lungs. This is normally 0.25 - 1.6 Woods, but I'm unsure if that is for adults, children or both. We want this to be a little higher in Lillian to prevent too much blood from going to her lungs at the expense of going to the rest of her body].
CINEANGIOGRAMS: [I am linking the actual videos of these after he is describing each of them.]
1. Ascending aortogram: An antegrade catheter was positioned in the proximal portion of the transverse arch [the part of her aorta between the heart and the top of the arch] through the Norwood anastomosis [it was accessed through the Norwood graph rather than through the heart for obvious reasons]. Evidence of a distal arch obstruction was appreciated. The measurement at the level of the arch was 2.9 x 2.9 mm. [this is where he saw and measured the arch obstruction]. Antegrade flow into the head and neck is easily appreciated through a left-sided aortic arch [even with the blockage, we have correct flow to her head and neck]. At the postero- inferior portion of the Norwood anastomosis at the level of the native aorta, one sees an extremely hypoplastic segment. [i.e., an extremely small segment of her aorta at the portion the Norwood graft ends and her own natural aorta begins]. Antegrade flow is seen through the coronary artery into a single right coronary arterial system. No contrast is appreciable through the left anterior coronary distribution [we see normal blood flow to the arteries that supply the heart, but only through the right coronary artery; we see no blood flow through the left artery. This is by far the biggest reason the heart that Lillian does have isn't pumping strongly enough]. Multiple collateral vessels are noted to arise from the right coronary system and traverse apically [we see blood vessels splitting off from the coronary artery she does have on the right that we wouldn't normally expect, and they travel to the apex of the heart in a way we really wouldn't expect.
Here are the videos he was viewing when he was describing this section:
From the front:
From the side with the blockage pointed out:
]
2. Balloon angioplasty: A balloon angioplasty using a 6-mm Tyshak balloon was performed across the area of coarctation. The balloon was noted to inflate to its maximum atmospheres with only a minimal residual waist [there was only a small amount of blood flow around the balloon.
Here are the videos from this section:
From the front:
From the side:
]
3. Post-angioplasty angiogram: Once again, a selective injection at the level of proximal aorta [same location as #1] is performed with contrast noted to enter into the single coronary arterial tree and better filling the right coronary system [seeing better blood flow in the system that feeds her heart itself, yet still without any appreciable blood flow to the left side]. Lateral projection demonstrates a moderate improvement in the dimensions of the distal aspect of the transverse arch post-angioplasty. [i.e., a moderate improvement in how wide the aorta is at the site of angioplasty
Here are the videos from this section:
From the front:
From the side:
]
4. Right ventriculogram: A right ventriculogram was performed to evaluate the Sano conduit [as a refresher, the shunt goes from her right ventricle to her pulmonary arteries to supply blood to her lungs]. There is a moderate to severe myocardial systolic contractility. [Again, I'm not exactly sure what he's referring to here. Myocardial refers to the heart muscle, systolic to the oxygen feeding circulation, so I know he is talking about there being an issue with general heart function, but he stops short of saying dysfunction, which I would expect.] Antegrade flow through the proximal, middle and distal portions of the Sano shunt appears to be widely patent [i.e., there is absolutely no issue with the shunt]. No evidence of distal branch pulmonary arterial stenosis. The branch pulmonary arteries are noted to fill in antegrade fashion with no evidence of obstruction. The distal right and left branch pulmonary arteries appear to be of adequate caliber. [The last 3 sentences basically say there's no evidence of a narrowing in her pulmonary arteries, which again go to the lungs; and there is normal blood flow.
Here are the videos from this section:
From the front:
From the side:
]
5. Final angiogram: A final angiogram using a Berman angiographic catheter was performed in the transverse arch. This demonstrates improved caliber across the distal Norwood anastomosis with improved filling of the single right coronary artery. Despite the catheter across the neo-aortic valve, no evidence of neoaortic valvar insufficiency is appreciated. On the lateral projection, a previously unnoticed region at the distal aortic arch reveals a neointimal disruption with no extravasation of contrast. [He saw a new small blockage in the arch, but it is not causing any issues.
Here are the videos from this section:
From the front:
From the side:
]
IMPRESSION: Lillian is a 3-month old with complex congenital heart disease consistent of a severely hypoplastic ascending aorta, and mitral atresia [there is no valve between the two chambers on the left side of the heart, this is insignificant as she doesn't even have a left ventricle]. She has undergone a Norwood palliation for her hypoplastic left heart syndrome with the inclusion of a Sano shunt. The Sano appears to be widely patent with antegrade flow noted into the right and left branch pulmonary arteries [this is as expected]. No evidence of pulmonary vein abnormalities is noted. She demonstrated a severe coarctation of her distal arch which underwent balloon angioplasty and resulted in an improved flow by contrast injection [coarctation = blockage, this is why she needed the cath]. She was to be transferred to the Cardiac Intensive Care Unit for systemic afterload reduction [giving her heart a rest] and acute management of her heart failure. A double lumen central venous catheter replaced her venous sheath in her right femoral vein and the single lumen arterial catheter was placed into the right femoral artery. These catheters will remain in place so as to allow for systemic medications to be delivered [they also allow us to draw labs without poking her]. Her data and information will be presented at the next patient care conference.
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