Week 4: Colds, TEEs, and Stem Cells

I picked up a cold that carried over into week 4. I did not want to interact with any doctors or patients while I was still sick (and be single-handedly responsible for a plague spreading through an innocent, possibly immune compromised population). Dr. Weinsaft suggested I spend my time in the lab and then start clinical rounds up again on Thursday. I am working with Dr. Ann Foley in Molecular Cardiology. My project is aimed at testing the hypothesis that visceral endoderm induces heart formation. I am using four different embryonic stem cell lines, and co-culturing them in embryoid bodies for the experiment.
On Thursday Brooke came with me to TEE where I am shadowing Dr. Healy. A very polite southern gentleman was one of the patients in the morning. He and the woman after him were sunbeams of cheer, and they were talkative and friendly throughout the test preparation. Many people aren’t that nice even when they are in comfortable situations, much less when they are feeling apprehensive about a fairly serious test. The gentleman patient had been having Transient Ischemic Attacks (TIAs) of increasing frequency. He would have an episode of garbled speech for 5 minutes, some memory loss, and shortness of breath. The cause of these episodes was unknown, he had never had a full stroke, and then two months ago it was discovered that his heart had gone into atrial fibrillation. The TEE was being done to look for a clot in the atrial appendage or the atrium. If a patient is going to undergo an ablation surgery for an arrhythmia or electrical cardioversion to reset the heart’s rhythm, a clot could be jarred loose and potentially cause a stroke. They did not find any clots in this patient’s heart.
The next patient was the youngest I had seen come in for a TEE. She was a young school teacher who had a stroke when she was 30, and had been put on aspirin. Now three years later she and her husband want to have a second child. Her cardiologist suspected that her stroke was the result of a clot crossing a septal defect, from one side of the heart to the other. Normally the lungs do a good job protecting against clots drawn up from the legs, but a Patent Formen Ovale (PFO) or hole between the upper chambers of the heart, can allow a clot to bypass the lungs and reach the brain. The TEE procedure was being done to check for the hole between the chambers and assess the size. The possibility of forming blood clots in her legs during pregnancy and then straining during labor increases the patient’s risk of stroke with the septal defect. During the TEE the cardiologist did find a medium to large hole between the atria. After the procedure was finished and the patient woke up, the doctor brought her husband and her father into the room to show them the image results. (The patient may not be able to remember seeing the images so it is nice to have someone else be able to describe it to them later.) TEE is still on recorded on VHS. There was some brief discussion about the patient’s options. Considering the size of the hole, the cardiologist recommended that an anticoagulant be used in addition to the asprin that the patient is already taking. If the patient became pregnant, for most anti-coagulants their use would need to be stopped before delivery of the baby, leaving her vulnerable to blood clots. One other option discussed was a device that would act as a plug for the PFO. It could be inserted by catheter, poked through the septum wall, and then sealed around the hole (like two discs clamping together on either side of the wall). Unfortunately, it has a complication risk of 1%. The patient would still probably need to be on a blood thinner with the device, but it would prevent any clots from crossing over. She and her family will have to decide what risks they want to take and how to best manage them. Doctors are almost like risk management counselors. Sometimes tests start to just seem like an assembly line of procedures and analysis, since there are so many people who need the test. When I actually see the doctors talk to their patients and discuss the ramifications of the tests, I realize that it isn’t as simple as “We know what’s wrong. Here’s your cure. You can go home.”