Journal of the Practice of Cardiovascular Sciences

QUIZ TIME
Year
: 2015  |  Volume : 1  |  Issue : 1  |  Page : 72--73

Electrocardiography quiz


Parag Barwad 
 Department of Cardiology, PGIMER, Chandigarh, India

Correspondence Address:
Dr. Parag Barwad
Department of Cardiology, PGIMER, Chandigarh - 160 012
India




How to cite this article:
Barwad P. Electrocardiography quiz.J Pract Cardiovasc Sci 2015;1:72-73


How to cite this URL:
Barwad P. Electrocardiography quiz. J Pract Cardiovasc Sci [serial online] 2015 [cited 2021 Jun 22 ];1:72-73
Available from: https://www.j-pcs.org/text.asp?2015/1/1/72/157578


Full Text

 ECG Quiz



Question - analyze the ECG [Figure 1].{Figure 1}

 Clinical Details



A 32-year-old male patient had an episode of palpitation lasting for 3 h. The onset was abrupt, but there was no hemodynamic compromise. There is a history of similar episodes since last 2 years, lasting for few hours with spontaneous termination. However, required intravenous verapamil for termination on few occasion. The echocardiogram done was normal.

Electrocardiography features

Regular tachycardia with right bundle branch block (RBBB) morphology, QRS duration of 120 msLeft axis deviationInverted P waves are seen, best in lead III (red arrow)Constant QRS and P relationship (red arrow).

Interpretation [Figure 2]{Figure 2}

Broad, complex regular tachycardia in young patients is usually supraventricular tachycardia with aberrancyHowever, any broad complex tachycardia not fulfilling the criteria for a typical bundle branch block (RBBB or left bundle branch block), may be a tachycardia of ventricular originRBBB usually has an associated right axis deviationThus, the present patient has a ventricular tachycardia (VT) arising from the left posterior fascicle (fascicular VT)Though atrioventricular dissociation is a diagnostic feature for VT, this is seen in only 50% of patients. In fact, up to 25% of patients in VT may have 1:1 ventriculoatrial conduction, as shown, in this case.

Further case details: The patient was taken-up for electrophysiological study, which showed recurrently inducible left posterior fascicular VT, for which a successful radiofrequency ablation was performed.

Comments

Fascicular VT is a relatively benign variety of VT arising from the left ventricle with re-entry within the posterior left fascicle as the possible mechanismElectrocardiography characteristics of fascicular VT are RBBB with left axis deviation/northwest axis, with relatively narrow QRSThis tachycardia usually does not cause hemodynamic compromise and occur in younger populationHowever, in few patients incessant tachycardia may cause left ventricular dysfunctionVerapamil/Diltiazem is effective in terminating this VT; Adenosine is ineffectiveRadiofrequency ablation has a success rate of 90%Early recognition and differentiating it from other VTs is important in view of its treatment strategy.