Cardiovascular, Physiology, USMLE Step 1 - Full Vignette with Extended Explanations

Описание: A 30-year-old woman living in a remote area arrives at a small clinic with sudden palpitations, chest fluttering, and lightheadedness while cleaning. Her vital signs reveal a rapid heart rate, oxygen desaturation improved by supplemental oxygen, and a regular narrow-complex tachycardia is seen on rhythm strip. With her medical history and limited access to advanced care, how should her acute symptoms and future risk be assessed?

VIDEO INFO
Category: Cardiovascular, Physiology, USMLE Step 1
Difficulty: Easy - Basic level - Suitable for medical students
Question Type: Natural History
Case Type: Resource Limited

Watch the video for explanation, or see the full explanation at: https://endlessmedical.academy/auth?h...

QUESTION
A 30-year-old woman living in a remote valley presents to a small clinic with sudden palpitations, chest fluttering, and lightheadedness that began while cleaning. Vitals: T 37.6 degreesC, pulse 218-224/min, RR 18/min, BP 146/11 mm Hg, SpO2 90% on room air improving to 95% with 2 L/min oxygen. The rhythm strip shows a regular narrow-complex tachycardia near 220/min without visible P waves. She describes two prior episodes in the past year that started and stopped abruptly....

OPTIONS
A. Paroxysmal AV-node-dependent supraventricular tachycardia tends to recur with sudden onset and offset in structurally normal hearts; short-term mortality is low, but recurrent episodes can impair quality of life and infrequently cause tachycardia-induced cardiomyopathy, making recurrence more lik...
B. Most adults with paroxysmal supraventricular tachycardia experience spontaneous permanent cure within weeks without therapy, so recurrence in the next 6 months is uncommon even without ablation.
C. Untreated paroxysmal supraventricular tachycardia commonly evolves into sustained monomorphic ventricular tachycardia with high near-term sudden death risk despite a structurally normal heart.
D. Paroxysmal supraventricular tachycardia invariably progresses to severe systolic heart failure within a few weeks unless ablation is performed emergently during the index episode.



Further reading:

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