Week 1 Cardiology Rotation Day 1

On our first day rotating in the Cardiology department, we saw two cases in the catheter lab with Dr. Huang. The first case was a 40 year old male patient with a past medical history of coronary artery disease due to familial hypercholesterolemia, who has had an LDL cholesterol of 400 and placement of 5 coronary artery stents despite his young age. Dr. Huang also mentioned that the patient's younger brother also has familial hypercholesterolemia and has triple vessel coronary artery disease (affecting the LAD, LCX and RCA) that necessitated 10 percutaneous coronary interventions and coronary artery bypass grafting (CABG).
The patient presented to the cardiologist after experiencing syncope, severe chest pain and cold sweats while riding his motorcycle. He then had a coronary angiogram that showed >90% critical stenosis in the left circumflex artery just distal to the bifurcation of the LCX & LAD, with restenosing of two of the previously stented arteries. Today's treatment plan was to place a stent in the LCX using balloon angioplasty to open the narrowed region of critical stenosis. However, after 4 attempts to inflate the balloon, the center of the stenotic region remained narrowed with no dilation whatsoever. Dr. Huang inflated the balloon to a maximum of 18 atm but there was no change in compliance of the artery due to severe calcification. He explained to us that inflating the balloon to a higher pressure was not an option due to risk of rupturing the artery, which could lead to cardiac tamponade and cardiac arrest, so he would be unable to place the stent and the patient would need surgery instead. The cardiac surgeon was consulted and they revised the treatment plan to include two options with similar long-term outcomes:
The first option was rotational atherectomy, an interventional coronary procedure that utilizes a high-speed rotational device that's coated with microscopic diamond particles. It rotates at high speed to break up blockages into tiny fragments that are small enough to be taken up by macrophages in the blood. However, this procedure has the risk of artery trauma (dissection, perforation, rupture or injury) and is not covered by national health insurance so the patient would have to pay $100,000 - $150,000 NT (~$5000 USD). The second option was Minimally Invasive CABG, which involves small incisions instead of a median sternotomy as with traditional open heart surgery and this procedure would be completely covered by NHI.

The second case we saw was another patient with coronary artery disease who had a 90% critical stenosis of the left circumflex artery. The treatment plan was to use balloon angioplasty to place a stent in the LCX via the brachial approach in the patient's right arm. However, after inserting the guide wire, Dr. Huang discovered that the patient had a tortuous axillary artery on the right side so he could not advance the wire any further due to risk of dissecting the artery, so he had to use the left brachial artery instead. Once the wire was in position, he inflated the balloon to 16 atm when it ruptured, indicating a hardened atherosclerotic lesion. A second attempt was made using the buddy wire technique, which involved adding a second coronary guide wire in the LCX to increase support for the balloon and provide stability for the guiding catheter, but the second balloon ruptured as well. A third attempt was made using the anchor technique and a smaller balloon, which involved inserting an additional guide wire into a non-target artery (the LAD in this case) to "anchor" it and provide support for crossing the guide wire into the LCX. Although this smaller balloon did not rupture, the stenotic region remained narrowed after the balloon was fully inflated.
After the procedure, Dr. Huang explained that a larger balloon could not be used due to risk of rupturing the artery and that the anchor technique was utilized because the patient had chronic total occlusion (CTO) of the LCX, which complicated the procedure. CTO is apparently encountered in 15-30% of coronary angiography patients and represents a 98-99% stenosis of the artery, which often prevents successful percutaneous coronary intervention. However, during the procedure they discovered that there was collateral circulation from the RCA supplying the occluded LCX, as a result of angiogenesis due to chronic myocardial ischemia.

Both of the cases today were rather complex and we learned that several things can get in the way of a successful PCI. I can definitely appreciate the patience and persistence needed for coronary angioplasty and the skill it takes to precisely maneuver the wires. It was interesting to watch the physicians troubleshooting and I can see the importance of having a few different methods to fall back on if the first attempt doesn't work in a complex case.
What surprised me was that for both of the cases, Dr. Huang brought the patient's relative into the viewing room and even into the catheter lab to show them the angiogram and discuss the patient's case with them, keeping them informed and making sure they understood the details of what was going on. He answered their questions thoroughly as he presented them with the treatment options, and I was impressed with his efforts to empower the patients and their families despite being behind schedule due to the complexity of each case.
After shadowing at hospitals in the US, it was a refreshing change to see the patients here benefit from the NHI, compared to watching American patients make difficult decisions about whether to get the treatments they need but can't possibly afford. I'm looking forward to seeing more of the positive impact of the NHI during the rest of our rotations here at TIHTC!