About Michelle Lin, MD

ALiEM Founder and CEO
Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco

Patwari Academy video: Torsades de Pointes

Torsades de pointes is a polymorphic form of ventricular tachycardia. Why does this occur? What does it characteristically look like? Why is this an important form of ventricular tachycardia to differentiate from the more classic monomorphic ventricular tachycardia? View this short 9 minute video on QT intervals and Torsades de Pointes.

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By Michelle Lin, MD|2019-01-28T21:59:21-08:00Jun 23, 2013|Cardiovascular, ECG, Patwari Videos|

Welcome new blog team member: Dr. Matt Astin

Welcome superstar Dr. Matt Astin to the ALiEM blog family. Matt is the Clinical Assistant Professor of EM and IM at Medical Center of Central Georgia, Mercer University School of Medicine. We’re incredibly happy here to add him as our new secret weapon in the social media and FOAM arena. After having met him in real-life at this past SAEM meeting, I can’t imagine a better fit for this team. Welcome! Follow him on Twitter: @mastinmd.

Here is brief bio by Matt:

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By Michelle Lin, MD|2019-09-10T14:03:22-07:00May 28, 2013|Life|

PV Card: Contraindications to Thrombolytics in Stroke

This Paucis Verbis (PV) card is an updated version of the PV card on Contraindications to Thrombolytics for CVA from September 10, 2010, based on the Stroke 2013 AHA/ASA new guidelines that were just published.¹ Some changes include…

There is new mention of new anticoagulants in the market with additional absolute exclusion criteria.
A blood glucose < 50 mg/dL has been upgraded from a relative exclusion to an absolute exclusion criteria. There is no more mention of glucose > 400 mg/dL as an exclusion criteria.
Seizure at onset of presentation has moved from an absolute to a relative risk.
Post-AMI pericarditis is no longer a relative exclusion criteria.

PV Card: Contraindications for Thrombolytics in Stroke

Adapted from [1]
Go to ALiEM (PV) Cards for more resources.

Reference

Jauch E, Saver J, Adams H, et al. Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2013;44(3):870-947. [PubMed]

By Michelle Lin, MD|2021-10-06T19:58:38-07:00May 23, 2013|ALiEM Cards, Neurology, Tox & Medications|

PV card: Early repolarization vs STEMI on ECG

You are handed an ECG for a 50 year old man with moderate chest pain for 2 hours now and no associated symptoms typical for ACS, PE, aortic dissection, or any other red flags of chest pain. He has no prior ECG’s on file.

Is this early repolarization or ST elevation MI?
Should I activate the cardiac catheterization lab?

Image courtesy of Dr. Steve Smith at HQMedEd-ecg.blogspot.com

Here are some great literature-based pearls compiled by Dr. Jason West (@JWestEM), an EM resident from Jacobi/Montefiore.

PV Card: ECG – Early Repolarization vs ST Elevation MI

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Adapted from [1–7]
Go to ALiEM (PV) Cards for more resources.

Furthermore, there is a formula to differentiate early repolarization vs STEMI, per Dr. Smith’s publication6:

(1.196 x STE60V3) + (0.059 x QTc) – (0.326 x RA V4)

STE60V3 = STE elevation height at 60 msec (1.5 small boxes) after the J-point in lead V3 (mm)
QTc = The computer-read QTc interval
RA V4 = R wave amplitude in lead V4 (mm)

A result of > 23.4 is predictive of a LAD occlusion causing a STEMI, rather than early repolarization.

P.S. The above ECG image shows early repolarization.

References

Brady W, Syverud S, Beagle C, et al. Electrocardiographic ST-segment elevation: the diagnosis of acute myocardial infarction by morphologic analysis of the ST segment. Acad Emerg Med. 2001;8(10):961-967. [PubMed]
Brady W, Perron A, Syverud S, et al. Reciprocal ST segment depression: impact on the electrocardiographic diagnosis of ST segment elevation acute myocardial infarction. Am J Emerg Med. 2002;20(1):35-38. [PubMed]
Smith S. Upwardly concave ST segment morphology is common in acute left anterior descending coronary occlusion. J Emerg Med. 2006;31(1):69-77. [PubMed]
Larson D, Menssen K, Sharkey S, et al. “False-positive” cardiac catheterization laboratory activation among patients with suspected ST-segment elevation myocardial infarction. JAMA. 2007;298(23):2754-2760. [PubMed]
Nfor T, Kostopoulos L, Hashim H, et al. Identifying false-positive ST-elevation myocardial infarction in emergency department patients. J Emerg Med. 2012;43(4):561-567. [PubMed]
Smith S, Khalil A, Henry T, et al. Electrocardiographic differentiation of early repolarization from subtle anterior ST-segment elevation myocardial infarction. Ann Emerg Med. 2012;60(1):45-56.e2. [PubMed]
Chung S, Lei M, Chen C, Hsu Y, Yang C. Characteristics and prognosis in patients with false-positive ST-elevation myocardial infarction in the ED. Am J Emerg Med. 2013;31(5):825-829. [PubMed]

By Michelle Lin, MD|2021-10-08T09:16:44-07:00May 16, 2013|ALiEM Cards, Cardiovascular, ECG|

Patwari Academy videos: Salter Harris fractures

Dr. Rahul Patwari discusses Salter Harris fractures in pediatric patients with a helpful mnemonic to help you remember the categories. He also poses several questions in the first video, which are answered in the second video.

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By Michelle Lin, MD|2019-01-28T21:59:38-08:00May 12, 2013|Orthopedic, Patwari Videos, Pediatrics|