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Updated: Mar 3, 2026

A Behavioral Assay for Mechanosensation of MARCM-based Clones in Drosophila melanogaster
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The exception to Marriot's sign.

Vivek Reddy1, Shanker Kundumadam1, Pradeep Kathi1

  • 1Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA.

Annals of Noninvasive Electrocardiology : the Official Journal of the International Society for Holter and Noninvasive Electrocardiology, Inc
|May 4, 2017
PubMed
Summary

Differentiating wide complex tachycardia is challenging. Marriott's sign, a specific criterion favoring ventricular tachycardia, was found to be an exception in this presented case.

Keywords:
atrial flutterbasicnoninvasive techniques-electrocardiography/clinicalventricular tachycardia

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Area of Science:

  • Cardiology
  • Electrophysiology
  • Internal Medicine

Background:

  • Wide complex tachycardia (WCT) diagnosis is critical in acute care.
  • Distinguishing ventricular tachycardia (VT) from supraventricular tachycardia (SVT) with aberrancy is a common clinical challenge.
  • Established criteria like Brugada and newer algorithms aid in differentiation.

Observation:

  • Marriott's sign, characterized by a taller first R wave peak compared to R', is a specific indicator favoring VT.
  • This case presents a WCT that is an exception to the typical presentation of Marriott's sign.
  • The patient's wide complex tachycardia did not conform to the expected pattern of Marriott's sign.

Findings:

  • The presented case highlights an exception to Marriott's sign in wide complex tachycardia.
  • This finding challenges the universal applicability of Marriott's sign for diagnosing ventricular tachycardia.
  • The specific ECG findings in this case require careful interpretation beyond standard criteria.

Implications:

  • Clinicians must be aware of exceptions to established diagnostic criteria for WCT.
  • Accurate differentiation of VT versus SVT with aberrancy is crucial for appropriate patient management.
  • Further research may be needed to refine diagnostic algorithms for complex wide complex tachycardias.