Sample Lecture – Cardio Vignettes


Next Step: Make Cards on the Automatic Key Concepts, and Vignettes

Remember, the more you automatically know what each sentence means on your test, the better you will do. There are 4 stages in making interpretation more automatic:

  • Stage 1: Unable to Make Pathophysiologic Chronologies in Either Timed or Untimed setting
  • Stage 2: Basic Pathophysiologic Chronologies, but with Significant Gaps
  • Stage 3: Detailed Pathophysiologic Chronology Without Time, but Unable to Consistently Generate PC During Timed Setting
  • Stage 4: Consistent Pathophysiologic Chronologies in Timed Setting

My goal with these vignettes is to help you reach Stage 4. How do you do so?

  • With the Automatic Key Concept cards, you can master the underlying information to move past Stages 1 + 2.
  • Then, with the Vignette/Pathophysiologic Chronology cards, you can teach yourself to make these connections on your exam.

Vignette/Pathophysiologic Chronologies:

Copy + paste these into your cards, to make the connections behind these vignettes more automatic.

A 65-year-old man has poorly-controlled type 2 diabetes mellitus for 20+ years. He has progressive renal failure and tingling in his hands/feet. For the past several months, he gets lightheaded when he stands up from a seated position.

What is the pathophysiologic chronology?


Heart failure and/or diabetic neuropathy of the autonomic nervous system → baroreceptor reflex dysfunction → (orthostatic) cerebral hypoperfusion


Born healthy, but poor lifestyle → insulin resistance ↑ → insulin production ↑ to compensate → amylin release ↑ → amyloid production in pancreatic β cells ↑ → β cell death → relative insulin deficiency → type 2 diabetes mellitus / blood sugar ↑ → non-enzymatic glycosylation of (peripheral) nerve axons → peripheral neuropathy (hand/foot tingling) + autonomic nerve dysfunction + kidney failure

Autonomic dysfunction → inability to compensate for preload drop when standing up (vagal nerve effect and/or decreased innervation of α1 receptors in blood vessels) → MAP ↓ → brain perfusion ↓ → pre-syncope (lightheadedness)

Alternative: DM2 → ischemic cardiomyopathy → ability to augment CO when standing ↓ → CPP ↓


A 67-year-old man comes to the emergency department because of a 1-week history of worsening left leg pain and a 2-day history of lightheadedness. He has a 1-month history of worsening upper mid-thoracic back pain, with 25-lb weight loss. His appetite has been unchanged. He has smoked 1 pack of cigarettes daily for the past 20 years. Heart rate is 100/min, and respiratory rate is 20/min. CT scan demonstrates a 2-cm mass in the pancreatic head, with an ultrasound of the left lower extremity demonstrating a femoral venous clot.

What is the pathophysiologic chronology?


Smoking → pancreatic cancer

Smoking + pancreatic CA → DVT → PE → MAP ↓ → cerebral hypoperfusion


Born healthy → smoking → risk of pancreatic cancer ↑ → weight loss / retroperitoneal pain (pancreas = retroperitoneal organ → back pain)

Presyncope (lightheadedness): Virchow’s Triad 2 of 3: Pancreatic cancer (hypercoagulability) + smoking (endothelial damage) → (large) DVT → unilateral leg swelling/pain. DVT embolizes to lungs → blockage of pulmonary artery → LV preload ↓ → SV ↓ → CO ↓ → MAP ↓ → CPP ↓ → presyncope (lightheadedness)

Tachycardia: MAP ↓ → baroreceptor stretch ↓ → vagal nerve activity ↓ → M2 ↓ / β1 ↑ activity in SA node → phase 4 depolarization ↑ in SA node → HR ↑


A 36-year-old woman goes to the ED with complaints of sudden lightheadedness for the past 4 hours. She smokes and uses OCPs. She recently flew from Seoul to Los Angeles. Her jugular veins are distended, with lungs clear to auscultation. Her lower extremities have mild pitting edema.

What is the pathophysiologic chronology?


Virchow’s Triad (3 of 3) → DVT → PE → right-sided heart failure / MAP ↓ → cerebral hypoperfusion


Born healthy → smoking + OCPs + venous stasis (Virchow’s Triad 3 of 3) → DVT → PE → pulmonary artery resistance ↑

Right-sided heart failure: pulmonary artery occlusion → back-up of blood into venous system → jugular venous distension/hepatomegaly/ pitting edema (capillary hypertension → fluid leaking into interstitium).

Clear lungs: no L-sided heart failure → no pulmonary edema → ”clear” lungs

Sudden presyncope: sudden PE → sudden drop in LV preload → SV ↓ → CO ↓ → MAP ↓ → CPP ↓ → presyncope (lightheadedness)

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Amazing sir😊

Dr. Palmerton

Thank you!!