Cardiology Rotation Day 3-5 (June 22-24, 2011)

June 22, 2011

The third day of our cardiology rotation started with observing pacemaker insertion in the catheterization room. The patient we visited yesterday has sick sinus syndrome, and hopefully the insertion of pacemaker can fix the problem. Dr. Tu was in charge of performing the procedure and Dr. Feng stayed in the monitor room as the supervisor of this operation. Since the X-ray would be frequently used throughout the whole process, Dr. Tu and his assistants needed to wear the heavy lead protection armor all the time. They first worked on the left subclavian area of the patient so that the leads can go from left subclavian artery via ascending aorta to the right chambers of the heart. Having the leads into the heart didn’t seem to be difficult, but inserting the leads into appropriate positions in the heart and ensuring the stable insertion are much more troublesome. Dr. Tu asked Dr. Feng several times to make sure that the leads are at right spots. And every time he inserted the leads into the tissue, he needed to pull the leads back lightly several times to make sure they are stably inserted. It took Dr. Tu more than one hour to insert the leads into the apex and sinus node properly. Once the leads were stably inserted, the expert from the pacemaker company used his programmer to find out the appropriate range of beating speed and adjusted the pacemaker according to that. The pacemaker was then connected with the leads and placed under the skin before suturing. The whole operation took about three hours.

In the afternoon, we met Dr. Po-Han Chou in ultrasonic room and observed him performing echocardiography on patients. Besides estimating the ejection fraction (EF) by measuring the change in width of left ventricle (LV), Dr. Chou showed us another more accurate way to estimate EF. The 2D image showing the entire left ventricle was first taken, and the EF was estimated using the change in LV area and LV length. This method is more accurate than previous one because the one measuring just width is under the assumption that LV is a sphere. Dr. Chou also mentioned that much more accurate estimation of EF can be obtained using 3D sonography. Besides echocardiography, Dr. Chou also used the ultrasound to check the inferior vena cava and hepatic vein for every patient. He said that because of prevalence of Hepatitis B in Taiwan, patients have more risk to have hepatocellular carcinoma and that can cause membranous obstruction of IVC.

June 23, 2011

Before we started observing Dr. Chou performing echocardiography, we got the chance to watch another physician use ultrasound to check the carotid arties. The sonographies of common carotid arteries, external carotid arteries, and vertebral arties were taken and the thickness of each artery was measured. This screening is useful to estimate the progresses of atherosclerosis and helpful to identify patients who have high risk of stroke.

Since Dr. Chou only had one patient this morning, he kindly provided Mickey and I the opportunity to perform echocardiography on each other. Dr. Chou guided us how to position the probe different to get the parasternal long axis view, short axis view, four chambers view, and five chambers view. When I had the probe on my hand, I started to know how difficult to have the probe on the correct spot to gain the view you want. It’s a skill that requires a lot of practice to do it right and obtain correct diagnosis. Dr. Chou told us that he practiced it every day during his fellowship. And his supervisor told him that the first two hundred and fifty times are usually wrong and one thousand times practice is required to start having confidence about the diagnosis. In the afternoon, we met Dr. Chieh-Yuan Huang in ultrasonic room and observed him performing echocardiography. One of the cases he had today had ventricular septal defect, supracristal type. And the echocardiography clearly showed the hole, which was estimated to be 0.8 cm. This experience showed us knowing how to use ultrasound correctly is a skill that required a lot of practices but would be very useful in screening and making diagnosis.

June 24, 2011

The last day of our cardiology rotation also started in ultrasonic room. In the morning, we observed Dr. Huang performing echocardiography. One of the patients he had today is a 48 years old male with severe heart problem and renal problem that requires hemodialysis. The echocardiography showed mitral annulus dilatation and tricuspid valve lesion that results in ascending jet back into left atrium. The heart was found to have almost no contractility and ejection fraction was estimated to be only 20%. His diagnosis includes multivessel disease and dilated cardiomyopathy is suspected. And according to Dr. Huang, the only treatment for this patient is heart transplantation, so he suggested patient to make consultation with the cardiovascular surgeon.

In the afternoon, we went to ultrasonic room again and observe Dr. Feng performing echocardiography. One patient came in has gauze on her left heel. Dr. Feng told us that he suspected that she has peripheral artery occlusive disease (PAOD) because of the chronic ulcer on her left heel, so he ordered her ankle brachial index (ABI) test. The ABI was found to be 0.55 for her right leg and 0.27 for her left leg. This suggested there is stenosis and confirmed the suspicion of PAOD, and angiogram will be done next week to further confirm the finding.

During this week of rotation in cardiology, I not only got to know various jobs of cardiologists (such as maintaining the BP, blood sugar, and cholesterol level of patients and inserting pacemaker) but also gain more understanding of echocardiography (like how to put the probe in right spot and how to interpret the images and obtain various parameters). Like Dr. Chou told us before, since heart is in charge to pump the blood to every part of our body, problems in various parts of body can be due to heart problem. Therefore these experiences I gained from cardiology are very useful for me no matter which specialty I go to in the future.

Cardiology Rotation Day 1 & 2 (June 20-21, 2011)

June 20, 2011

Our first day in cardiology started with observing Dr. Kuei-Feng Chen in his outpatient clinic. Since he is the director of the cardiology department, he had so many patients that I wonder if he can finish all of them in the morning. But my doubt got cleaned up right away after I saw that he finished each patient visit in less than four minutes. He explained that he can do it so fast because most of them are his long-term patients and he knows each of them pretty well. From Dr. Chen, we learned that it’s important for cardiologists to control patients’ blood pressure, blood sugar, and blood lipid level. The side effect of medications (e.g. peripheral edema from Amlodipine, a long-acting calcium channel blocker) is another thing a cardiologist often needs to deal with.

After leaving Dr. Chen’s outpatient clinic, we went to ultrasonic room where cardiologists perform echocardiography. For rest of the day, we observed Dr. Wen-Kai Feng and Dr. Chung-Chih Tu performing echocardiography on patients. From them, we learned that echocardiography is a very useful diagnosis tool to screen possible heart problem on the patients. For example, echocardiography was used on a pneumonia patient to see if there is any vegetation on his heart valves. They also showed us how to gain important parameters such as left atrium diameter, flow velocity, and ejection fraction using various features on the echocardiography machine. This experience gave me an idea what the echography can do to help us making diagnosis regarding heart.

June 21, 2011

Mickey and I met Dr. Chen, the director of the cardiology department, in the ultrasonic room. We observed Dr. Chen performing echocardiography, and he told us what he interpreted from the image. Dr. Chen usually checked the patient’s EKG or/and CXR first before performing the echocardiography. He told us that EKG, CXR, and echo are the three most common diagnosis tools used in cardiology and each has its own advantages. For example, CXR can give us the size of the heart. EKC can tell us if the patient has bundle branch block, arrhythmia, MI, etc. And echo allows us to know if there is any shunt or heart valve problem. We also observed that a lot of patients receiving echo have mitral prolapse. According to Dr. Chen, mitral prolapse is pretty common. Patients with echo showing mitral prolapse usually are still considered normal and don’t receive treatment for that.

Besides mitral prolapse, we also got chance to see other valve problems such as vegetation, mitral regurgitation, and aortic regurgitation. Actually one of the patients Dr. Chen had today has regurgitation of all four heart valves (mitral, tricuspid, aortic, and pulmonic). And it’s amazing to be able to see the heart with all four valve regurgitated on echo. Another rare case we observed is a patient having mitral valve replacement with mechanical valve due to mitral stenosis. The prosthetic valve cannot be seen very well on the CXR unless the valve is totally close as the moment of taking X-tray. But the echo clearly showed the valve and the blood flow passing through it. And it’s astonishing to see the valve still working well after almost twenty years since the replacement.

We also saw many of the patients receiving echo are young healthy male before going to military service. Conscription is still used in Taiwan to recruit people to military service, and complete physical examination will be performed to check the body condition of each man before serving the nation. Many of those young men having history of heart problem (especially those with congenital heart defects) will come to get echo for further checking their heart condition. And we are lucky to see one of the classical congenital heart defects, tetralogy of Fallot. The patient received surgery to fix it when he was small, and according to Dr. Chen, that operation is really successful since he didn’t see any sequela from tetralogy of Fallot on his echo. Dr. Chen also said that this case is rare and a little bit difficult to interpret even for experienced cardiologists.

Besides observing echocardiography, Dr. Chen also kindly provided us the opportunity to perform 12-lead EKG on each other. So Mickey and I went to EKG room and learned how to use it by observing the technician doing it. Then we performed 12-lead EKG on each other. And it’s exciting to be able to look and study my own EKG. In the same EKG room, Dr. Chen also showed us some EKG from stress test while he was making final diagnosis. One case he showed us had the “delta wave”, the classical sign of Wolff–Parkinson–White syndrome (WPW).

After finishing the interpretation of EKG from stress tests, we went to the wards with Dr. Chen. One patient we visited will have pacemaker insertion tomorrow. He is a long-time patient with Dr. Chen for more than twelve years. And Dr. Chen showed us the old charts and pointed out how he changed the patient’s medication over time as the heart rate of the patient went slower and slower (From beta blocker to no beta blocker to aminophylline). Since the operation will be held in catheterization room, Dr. Chen brought us to the room and provided us the opportunity to observe the operation tomorrow.