Medical School 2020, Year 2, Week 10

From our anonymous insider…

Cardiology week begins with a one-hour lecture and two-hour workshop focusing on interpreting electrocardiograms (ECG or EKG). An electrophysiologist with a Southern accent who is celebrating his 40th year reading EKGs implored us to “develop a systematic way to read EKGS. Don’t just jump into the details.” He commented on 30 slides of pathological EKGs. Afterwards, we broke up into seven-person groups and went through 20 example EKGs with a fellow. Straight-Shooter Sally was unimpressed with our fellow: “When asked why this is a LBB [left bundle branch], all she would say is, ‘That’s what a LBB looks like. It’s pattern recognition.’ That does not help us. Connect the physiology to the EKG.”

We next traveled to the clinical room to practice on Harvey, a cardiopulmonary patient simulator, with a soft-spoken retired Navy cardiologist who had become a class favorite last year. “Studies show that it requires hearing about 200 murmurs to get decent at identifying one on a patient.” Jane put her stethoscope on Harvey’s chest while the rest of the students listened to the simulated heart sounds on wireless stethoscopes. “Enter number 24”. The heart sound changes from a crescendo-decrescendo systolic ejection murmur of aortic stenosis to the holosystolic murmur of mitral regurgitation. Jane found it challenging to determine whether a murmur is systolic or diastolic. “It was really helpful to listen on Harvey while feeling for the pulse. If the murmur happens with the carotid upstroke, it is a systolic murmur.”

Each group also rotated through two patient volunteers. Patient #1: accommodating 40-year-old female recently diagnosed with pulmonary stenosis after an enlarged thymus was removed. We felt a thrill (vibration felt with hand) under her left clavicle and a loud systolic murmur that radiated to her back. Patient #2: genial 75-year-old male with mild mitral regurgitation, typically a benign finding due to the changes accompanying an aging heart. The murmur was barely audible after concentrating for 45 seconds. The cardiologist asked, “How could we bring out the murmur?” After several blank looks from the group, Gigolo Giorgio proposed, “Make him squat?” “Yes!!,” exclaimed the cardiologist. “Squatting would certainly work, but we’ll just ask him to flex his arms together.” With an increased afterload (blood vessel resistance), the left ventricle pushes more blood backwards through the mitral valve orifice. This accentuates the mitral valve regurgitation murmur. We asked the patient to stand up. The decreased preload (the total amount of blood returning to the heart) completely eliminated the murmur.

A pediatric cardiologist, recently retired from clinical practice, introduced congenital heart defects. She emphasized the cyanotic (“blue baby”) defects including Tetralogy of Fallot (four heart defects combined) , transposition of the great vessels (left/right reversal creating two nearly separate circuits), and tricuspid atresia (closure of the tricuspid valve orifice). She referred to current events while looking at the swirling color doppler field of flow through an obstructed aortic valve: “Looks like [Hurricane] Irma.” Fortunately for her, she’s already retired because Generation Politically Correct was gunning for her. Pinterest Penelope: “It is inappropriate to make light of the suffering of those who have gone through Harvey, Irma, and Maria.” Two classmates piled on.

The pediatric cardiologist continued regarding the importance of the ductus arteriosus in these “duct-dependent disorders.” The ductus arteriosus is a short connection (right to left) shunt between the left pulmonary artery (carrying deoxygenated blood from right ventricle to left lung) and descending aorta that allows oxygenated blood from the uterine vein (from the mother) to bypass the lungs and mix with the systemic circulation. Compared to normal oxygen saturation after birth, the fetus survives on a lower oxygen saturation in-utero.

When baby takes her first breaths, the pulmonary vasculature opens up. Usually the ductus arteriosus closes. However, if the ductus arteriosus fails to close (patent ductus arteriosus or PDA) the shunt reverses direction, causing oxygenated blood to overload the pulmonary circulation. A reverse-flowing shunt isn’t bad for everyone. Patients with an obstructed right ventricular outflow tract, such as babies with Tetralogy of Fallot or tricuspid atresia, require the right-to-left shunt PDA to get blood into their lungs. “A patent ductus is the only thing keeping the baby with Tetralogy of Fallot alive. Pump those prostaglandins. Do NOT let it close.”

Tetralogy of Fallot was a lethal disease until the 1940s when a surgical procedure was developed to connect the right subclavian vein (part of systemic circulation) to the right pulmonary artery for oxygenation. This procedure is front-and-center in the identity politics of medicine, having been developed by Alfred Blalock, a white male surgeon, Helen B. Taussig, a white female cardiologist, and Vivien Thomas, a black male lab technician. People fight about whether the procedure should be called “Blalock–Taussig” (BT) or Blalock–Thomas–Taussig (BTT) and also how much credit should be assigned to the three collaborators. The discussion regarding the race and gender identification of the creators has outlasted the original procedure. Today a synthetic dacron shunt is placed between the right subclavian vein and right pulmonary artery. “Eventually the child will grow out of the BT shunt,” said our pediatric cardiologist, However, the heart has grown enough so surgeons can perform a more complicated fix.”

Our patient case: Becca, a female neurotrauma nurse, age 27 at the time, returned to work two months after giving birth to her second child. “It was just a normal day. I had two great patients, which means it was somewhat boring — not stressful at all. I was pushing some meds to my patient when I had this odd sensation in my neck. It wasn’t a sharp pain, but a strong tingling sensation. I went over to the charge nurse who sat me down.” Becca’s heart rate was in the 50s (bradycardia). She felt a searing pain in her chest and was sweating profusely. “It felt like someone was stabbing me through the front of my chest all the way out the back.”

Becca recounted how she was hauled down to the ED in a gurney. “Let me tell you something: patients remember what they hear in the hospital. My scrubs were soaked with sweat by the time I got to the ED. I started taking off my scrubs and even sports bra. I am sure people saw me naked through the makeshift curtains in the ED. Some ED nurse blabbered, ‘What’s wrong with her?’ It was just rude.” Her cardiologist, the retired Navy doctor who taught our simulator session (above), commented, “A lot of residents make offhand jokes about patients. Try to do it in the resident lounge.”

The ED physician performed an EKG. “I turned my head to look at the screen. Those Tombstone T waves are still seared into my head.” [Tombstone T waves suggest a myocardial infarction (“heart attack”).] “This is when I was called down to the ED,” explained her cardiologist. She was taken to the Cath Lab while a nurse called her husband, at home with the 2-year-old and 2-month-old. Becca: “I’ve sent several patients to the Cath Lab, some don’t come back. I was freaking out all alone.”

“We inserted a catheter through Becca’s femoral artery up to her heart. Pretty quickly we realized we were not dealing with a typical MI caused by a thromboembolism,” explained the cardiologist. He showed several images of the catheterization.  A student asked, “How could you tell this was not a thromboembolism?” The cardiologist responded, “This is why they pay me the big bucks.” [Interventional cardiology is one of the highest paid specialties, if not the best with explanations.]

Becca had spontaneous coronary arterial dissection (SCAD) of her left anterior descending artery, the main artery that supplies both ventricles. From Wikipedia: “a dissection is a tear within the wall of a blood vessel, which allows blood to separate the wall layers. By separating a portion of the wall of the artery (a layer of the tunica intima or tunica media), a dissection creates two lumens or passages within the vessel, the native or true lumen, and the ‘false lumen’ created by the new space within the wall of the artery.”

SCAD is a rare condition, accounting for fewer than 0.4 percent of heart attacks, but is more common during the postnatal period. This increased risk may be due to the the progesterone surge that weakens connective tissue to prepare for the baby traversing the vaginal canal. The progesterone also weakens connective tissue in blood vessels, thus enabling false lumens to develop.

Coronary dissections can be difficult to stent (putting a tube into the collapsed vessel, then inflating). “Sometimes it pays to be lucky instead of good.” The cardiologist got the catheter through the true lumen instead of the false lumen. “I’ve only dealt with two coronary dissections in my lifetime. I knew I did not have my catheter through the false lumen because I did not have to put much force on the catheter to move it through the left coronary artery. If it had been the false lumen, I would eventually have gotten stuck where the lumen ended.”

The cardiologist placed the first stent where the false lumen ended and worked his way back to where the dissection originated (working from distal to proximal). This required three stents total before perfusion normalized.

Becca’s rehab included a psychology consult. “It was hard for me to not think about how close I was to dying. I would lie awake scared that this could happen again. I still see my psychologist periodically.” The cardiologist: “Fifty percent of individuals experience depression during the first year post-MI.” Becca returned to work at the neurotrauma ICU after 1.5 years and exercises regularly. She gets an annual echocardiogram. “One thing [the cardiologist] told me is that I cannot have another child.”

During a brief intermission, our class joked about the weekly newsletter section on “How to Save Money”. Recommendations submitted by former students included (1) Make your own laundry detergent pods, and (2) Take up offers for food from friends. The cardiologist chimed in, “Does anyone have a part-time job?” One of our classmates drove Uber five times per month during M1 year, but he has stopped this year. The cardiologist commented that one of his classmates paid for medical school by working as a cab driver while another worked as a part-time cop. “Getting shot at was his stress relief from studying. He is now a trauma surgeon.” Classmates noted that tuition has gone up so much faster than wages that even paying for undergraduate tuition would be impossible today.

After the patient case concluded, the cardiologist summarized myocardial infarction complications. The danger of a MI does not end during the acute event. After the risk of cardiogenic shock or sudden cardiac death from an arrhythmia, there is significant remodeling of the necrotic tissue. Over the next few days, white blood cells infiltrate into the tissue to eat up the dead tissue. During this period there is a significant risk of ventricular wall rupture, in which blood flows from the heart into the pericardial sac. Blood filling the sac around the heart compresses the heart, preventing pumping (cardiac tamponade). “You die pretty quickly from a free wall rupture.” Weakened tissue can also cause a papillary muscle (“heart strings”) tear that holds the mitral valve from prolapsing during systolic contraction. Over months and years, remodeled scar tissue may develop arrhythmias and aneurysms. “An MI does not end after the two-week hospital stay. Patients need to be followed for life.”

Our ethical group met for a 1.5-hour discussion on patient autonomy and veracity. Nervous Nancy, an attractive, intelligent female who asks great questions at the speed of sound, worked as a CNA and scribe for a large health system in the ED and orthopedic unit before medical school.  She recounted, “Patients would come in on lawyers’ directions to get a payday because they knew the hospital would settle rather go to court. We had this one woman purposefully fall off a bed that did not have the railing up. She got one million dollars.”

Lanky Luke continues to scoff: “I want a talk from a malpractice lawyer and from a physician reflecting on their experience about getting sued by a patient. Not from some overpaid ethics professor. Why do we as physicians get to decide what is or is not ethical. We should first be taught the Law. Yes, sometimes there will be grey areas. Those situations should be highlighted and settled through the legislative process.” (Luke hopes to go into politics after graduation.)

Classmate political activism continues with a Facebook post from Type-A Anita regarding Trump’s Department of Education relaxing requirements that universities run sexual assault tribunals:

I think that taking what [Education Secretary Betsy DeVos] says at face value is dangerous. This administration doesn’t care about sexual assault victims.

Do you have any idea how hard it is to file a sexual assault claim on most campuses? Or how degrading [sic] victims are made to feel during this process? … The students Betsy is looking out for here are rapists, who already have the entire system at their backs. … Even if the school does something, it will take forever and their rapist will most likely be allowed to stay on campus, finish their degree, or be given a slap on the wrist. It’s laughable if you seriously think rapists on campuses are actually punished – the vast majority aren’t dismissed from school.

… I do not care if rapists feel their rights have been taken away from them under these university Title IX programs. University’s [sic] have professional Title IX coordinators, larger universities have whole departments. It’s not asking for the sun and the stars for schools to pay professionals to advocate for sexual assault victims on campuses. These programs force administrations to listen to victims over fucking rapists, and still so many victims don’t get any semblance of justice.

… And this isn’t just about rape, it’s about all forms of sexual assault, which by the way isn’t a fucking bipartisan issue. Conservatives literally voted for a man who bragged about assaulting women…

Nearly half of our class clicked “Like” on Anita’s post, roughly one third of which is reproduced above.

Jane and I went to the mall. A 40-year-old sales clerk asked what we did and then told us about having dilated cardiomyopathy (enlarged heart). “If my meds don’t start working, I have to get a heart transplant.” He recalls his doctor saying something about a viral infection. We spent the drive home pondering the possible causes. Dilated cardiomyopathy is typically familial, but we both thought of Coxsackie type B virus and Chagas Disease (prevalent in Central and South America, caused by the Trypanosoma cruzi).

Statistics for the week… Study: 14 hours. Sleep: 5 hours/night; Fun: 2 nights. Example fun: Jane and I went to a concert with Jane’s sister, a nurse on the neurotrauma unit, and her two friends, a fellow female nurse on the unit and an autopsy assistant at the hospital who doubles as a part-time stand-up comedian: “If I were stranded on an island after a plane crash I would know exactly what cut to take out of the the dead bodies. Tenderloin dinner for me.”