Black Pean Information #26

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Medical commentary on episode 7 (3)

This time, I’ll talk about Shouko’s surgery.

Shouko had two diseases, aortic valve incompetence and atrial fibrillation. I’ll explain them both separately.

Aortic valve incompetence

The heart has four chambers, each separated by valves (doors that open only in one direction) so that blood only flows in the right direction.

In aortic valve incompetence, the aortic valve is a door at the exit from the heart that allows blood to flow from the left ventricle into the aorta and then to the rest of the body. The condition where the aortic valve does not close properly is called aortic valve incompetence. As its name says, valve closure is insufficient (incomplete) in this disease. If the aortic valve doesn’t close properly, blood that has been sent from the aorta towards the rest of the body flows back into the left ventricle. Even though the left ventricle sent the blood to the rest of the body, it flows back in again and again, which is a major problem. Even though it is working so hard to send blood to the rest of the body, it comes back, which causes a burden (cardiac load). The heart doesn’t close properly so it can’t use its strength effectively, and when the heart expands and stretches its muscle, it loses strength (like overstretched gum). It can’t send out the blood that the rest of the body needs (heart failure). With aortic valve incompetence, it’s best to operate before the cardiac muscle is overstretched like that. You can do aortic valve replacement, replacing the valve with a prosthetic one, or you can repair the aortic valve by aortic valvuloplasty.

Aortic valve replacement for aortic incompetence is one of the first types of surgery that cardiovascular surgeons learn in basic training (another basic surgical technique is atrial septal defect surgery). Although this is a basic surgery, it isn’t simple. There are no simple kinds of heart surgery. They are all of at least medium difficulty or above. My first operation as a lead surgeon was aortic valve replacement surgery for aortic incompetence, too, and that morning my boss suddenly told me “you'll do the surgery today”. This was at Sendai Kousei Hospital, four years after I graduated. My superior had told me in advance “the next time we get an AR [aortic regurgitation, which is the same as aortic valve incompetence], you’ll be lead surgeon, so get ready for it”, so I had studied every day and was ready for it, but when I actually had to be lead surgeon I was more nervous than I’d ever been before. If I made the slightest mistake in the steps of the operation, I’d be scolded with a fiery rage and maybe I’d never get to do surgery again. My boss seemed like he’d seriously say “you have no talent, so you’re not qualified to be a heart surgeon. You should quit. You’ll cause problems for the patients.” I don’t know how many doctors had quit at that stage. He wasn’t Dr Tokai, but he seemed like a person who’d really say “doctors with no skill should die”.

First, you make an incision in the skin. Then, while holding gauze in your left hand and a scalpel in your right hand, you insert the scalpel into the skin vertically, then use an electric scalpel to cut through the fat and muscle down to the bone. Next, you use a medical electric saw called a striker to cut through the sternum bone. Holding tweezers in your left hand and the electric scalpel in your right hand, you stop the bleeding from the sternum’s bone marrow, cover the bone marrow with cloth, use a rib retractor to open up the chest and use gauze to quickly remove the fat on top of the pericardium. With tweezers in your left hand and an electric scalpel in your right hand, you make an incision in the pericardium, lift up the pericardium with silk thread and have the assistant cut the thread. Next, in preparation for setting up the heart-lung machine, you check the ultrasound image of the inside of the aorta, then have the anaesthetist administer heparin...

For each step in the procedure, you need to know what to hold in your left hand, what to hold in your right hand, what to be careful of, what angle to hold the needle at and where to insert it and remove it again with millimetric accuracy, what instructions to give the assistant, which tools to have the scrub nurse prepare next, what problems the heart-lung machine could have... These things are all fixed in advance, so if you can’t remember it all you’ll be beaten up. “Don’t you know how risky this is? Of course you should have memorised it! Of course you should have been prepared!” Most people got shaky hands from being nervous and couldn't do anything, and they were kicked out of the operating room halfway through.

I somehow managed to see it through until the end, and I felt like I could see the path towards becoming a real heart surgeon open up in front of me just a little. It’s an extremely happy memory.

Even young patients like Shoko can need aortic valvuloplasty (like we saw in episode 1, too). We might not be able to insert a prosthetic valve, and it can have the advantage that they won’t need pharmaceutical treatment. Compared to valve replacement, valve repair is more difficult, and this isn’t a surgery that beginner heart surgeons can do.

Atrial fibrillation

Next, atrial fibrillation, which is a type of arrhythmia. There are both dangerous and not-so-dangerous types of arrhythmia. A typical example of a dangerous arrhythmia is “VF”, which we have seen in this drama. VF is ventricular fibrillation, where the left ventricle spasms repeatedly and can’t send blood to the rest of the body, which is very dangerous. This can be resolved using an AED, so even ordinary people should know about this dangerous kind of arrhythmia.

On the other hand, one not-so-dangerous type of arrhythmia is atrial fibrillation. One cause of atrial fibrillation is valvulopathy, where the valve does not work properly, causing a burden on the atrium that leads to atrial fibrillation. It can also be caused by drinking alcohol, stress, thyroid disorders, ageing, etc.

Since it is the atrium spasming and not the ventricle, this isn’t as dangerous. Blood flow from the atrium to the ventricle depends more on the ventricle's strength when expanding. When the ventricle expands, most of the blood is pulled from the atrium into the ventricle, and the contraction of the atrium is less important for this flow. In other words, even if the atrium is spasming, blood can still flow properly.

Although atrial fibrillation is not dangerous in itself, the biggest problem is if the ventricle starts to spasm, causing blood to build up in the atrium due to a lack of blood flow, which can lead to a blood clot forming inside the atrium. Just like how garbage can easily build up in a river with a weak current, if the blood flow is poor, a clot can easily form in the left atrial appendage. I explained about the left atrial appendage before, when Sera sutured one in the emergency room after the accident.

If a blood clot forms and travels from the left atrium through the left ventricle and aorta into the brain, this can cause a stroke, leading to paralysis or impaired consciousness. Therefore, people with atrial fibrillation who can easily develop clots should take medicine to improve their blood flow.

Shouko probably didn’t have a clot during the preoperative checks, but at the end of the aortic valve surgery with the Caesar, the transoesophageal ultrasound showed a clot in her left atrial appendage. Maybe the heparin drip wasn’t effective for improving her blood flow.

No matter what the hospital director said, if you discover a clot in the left atrial appendage during surgery, you can’t just leave it alone. Dr Takashina did well to remove the clot from the left atrial appendage with the Caesar.

Dr Takashina and specialist terms

This is a medical drama, so there is quite a lot of specialised terminology, and the actors all work hard to learn it every time. In particular, Dr Takashina has a lot of explanatory lines, which must be very difficult. In reality, we use a lot of abbreviations and don’t speak in long Japanese sentences. “Do an atrial valve replacement for atrial regurgitation” becomes “do an AVR for AR”, and “mitral valvuloplasty for mitral regurgitation” becomes “MVP for MR”. I’m not 100% confident that I could say these lines properly like the actors do. By the way, apparently Dr Takashina’s hardest line was “Let’s do a bilateral pulmonary artery thrombectomy through a left thoracotomy”.

We’ve quickly come up to episode 8. There will be big changes as we reach the climax of the story, and Dr Tokai, Prof. Saeki, Prof. Nishizaki and Nekota will appear as you’ve never seen them before. You’ll gradually understand the mystery of the black pean too, so please look forward to it.