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VOLUME 3 , ISSUE 2 ( July-December, 2020 ) > List of Articles


Alternating Bundle Branch Block or Pyridostigmine-induced Mobitz Type II Block Masquerading as Acute Coronary Syndrome

Akula Hymavathi, Sarat C Uppaluri

Citation Information : Hymavathi A, Uppaluri SC. Alternating Bundle Branch Block or Pyridostigmine-induced Mobitz Type II Block Masquerading as Acute Coronary Syndrome. Journal of Medical Academics 2020; 3 (2):63-66.

DOI: 10.5005/jp-journals-10070-0060

License: CC BY-NC 4.0

Published Online: 01-12-2020

Copyright Statement:  Copyright © 2020; The Author(s).


Background: “ST-T changes in the ECG!!” These words are enough to get the emergency doctor to spring into action. These changes can be diffuse and/or non-specific but we should rule out all emergent and urgent causes before shifting the patient to the specialist. To err on the side of dangerous etiology is the dictum. Introduction: Out of all emergency department (ED) patients with undifferentiated chest pain, 7% will have ECG findings consistent with acute ischemia or infarction, and 6–10% of those in whom cardiac markers are ordered will have initially positive results. Of all patients with the possible acute coronary syndrome (ACS), 5–15% ultimately prove to have ACS.1 Shortness of breath with chest pain mostly has a cardiac origin in the presence of dynamic ECG changes. We had managed a patient with rapidly evolving ECG changes, chest pain, palpitations, and grade III–IV dyspnea. In the chaotic environment of a busy ED, the most probable diagnosis here will be ACS. Comorbid conditions like diabetes mellitus, hypertension, and prior coronary artery disease (CAD) are commonly enquired. However, other long-standing illnesses like myasthenia gravis (MG), as in our patient can be easily missed if a patient is not forthcoming with history. We experienced a similar confusion when in the cacophony of chest pain, dyspnea, and T wave inversions with bundle branch blocks, ACS protocol was initiated and a simple diagnosis was missed. The significance of the alternating bundle branch block (ABBB) will be presented to the readers.

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