Learning From Zebras
Read the Cardiology Cases from the NEJM
I suspect we were all taught during training that “When you hear hoof beats think horses and not zebras.”
That’s always good advice, but we can learn a lot from the zebras. I routinely look at the cases in the New England Journal of Medicine (NEJM) to see if they might be pertinent to cardiology. The July 13, 2023 Case Records from Massachusetts General Hospital (MGH) discussed a man with eyelid swelling and some mild cardiac thickening who had light chain amyloidosis.(1) The October 26, 2023 MGH case discussed a man with heart failure symptoms who had carcinoid heart disease.(2) The November 2, 2023 NEJM Clinical Problem-Solving case discussed a man with atrial fibrillation (AF) after an AF ablation who presented with dyspnea, leg swelling, and abdominal bloating.(3) His cardiac magnetic resonance imaging suggested constrictive pericarditis, but he died before a pericardiectomy could be done. His autopsy showed an isolated mesothelioma of the pericardium without pleural involvement.
I do not expect to diagnose systemic amyloidosis, carcinoid heart disease or cardiac constriction in my next patient, but I might. Reading the case records of the NEJM is an entertaining way to learn about unusual conditions from experts. These cases always include a differential diagnosis which discusses how the “zebras” differ from the “horses” so these cases teach about both the unusual and the more mundane. I encourage students, trainees and other clinicians to make reading these cases a habit. They are an engaging way to stay current.
1. Wolkow N, Romo LV, Edwards CV, Stagner AM. Case 21-2023: A 61-Year-Old Man with Eyelid Swelling. N Engl J Med. 2023 Jul 13;389(2):166-175. PMID: 37437147
2. Luis SA, Chung R, Stefanescu Schmidt AC, Clark JW, Pearson DS Case 33-2023: An 86-Year-Old Man with Shortness of Breath. N Engl J Med. 2023 Oct 26;389(17):1602-1613. PMID: 37888920.
3. Kaur G, Sabatine MS, Schaefer I-M, Sun Y-P, Loscalzo J. Encased in Peril. N Engl J Med. 2023 Nov 2;389(18):1709-1716.PMID: 37913509
4. Wolkow N, Romo LV, Edwards CV, Stagner AM. Case 21-2023: A 61-Year-Old Man with Eyelid Swelling. N Engl J Med. 2023 Jul 13;389(2):166-175. PMID: 37437147
This piece is from my “500 Rules of Cardiology”, not really rules, not really 500, and quite presumptuous on my part, but they are simple sayings and principles I have used clinically and in teaching. Please share them with trainees and colleagues. I send them out to an email list so if you send me your friends’ email, will add them to the list. I also publish them on my blogs on Medium & on Substack. Both are free. I am trying to shift over to Substack so use that one if possible.
Paul D. Thompson, MD