One MCQ a day – 12.04.2015

Answer to the question on 11.04.2015

Answer : D

localizing the AP

1. Left free-wall APs are associated with positive delta waves in lead V1 and negative delta
waves in leads I and aVL

2. The ECG in a patient with a manifest right-sided AP shows a negative delta wave in lead V1 and positive delta waves in leads I and aVL.

3. The polarity of the delta waves in leads III and aVF is helpful in localizing the AP on the AV annulus. Positive delta waves in these leads point to an insertion at the anterior, anterolateral, or lateral aspect of the tricuspid or mitral annulus. Negative delta waves in these leads are consistent with an insertion at the inferior aspect of the AV valves (e.g., posterior, posterolateral, or posteroseptal aspect of the tricuspid or mitral annulus)

4. For anteroseptal and midseptal accessory pathways, a few additional observations are helpful. Typically, a negative delta wave is present in lead V1 in patients with anteroseptal and midseptal accessory pathways. Septal accessory pathways may be distinguished
from right free-wall pathways if the precordial QRS transition (negative to positive) occurs at or before lead V3. If the transition occurs between V3 and V4, the amplitude of the delta
wave in lead II is examined. An amplitude of 1.0 mV or greater is consistent with a septal AP, whereas amplitude less than 1.0 mV suggests a right free wall connection. In a patient whose ECG is consistent with a posteroseptal AP, a steeply negative delta wave in lead II is suggestive of an epicardial connection.

(Ref: Cardiac Electrophysiology: From Cell to Bedside: 6th edition, Page : 758)

MCQ 12.04.2015

A 32 years old male patient presented to emergency with complains of palpitation for 30 mins. He has history of recurrent episodes of palpitation for last one year. On examination his pulse was variable, blood pressure was 100/70 mmHg. The ECG is shown below. Which is the initial drug of choice for this patient

WPW-AF

A. Intravenous procainamide

B. Intravenous adenosine

C. Intravenous diltiazem

D. Intravenous Verapamil

Keywords: Cardiology, Multiple choice questions, medical students, Electrophysiology

3 thoughts on “One MCQ a day – 12.04.2015

  1. Your questions are indeed though provoking and helps in easy way of learning. Thank you for such a nice learning platform

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