Doubling of the Ventricular Rate by Interpolated Junctional Extrasystoles Resembling Supraventricular Tachycardia
Article first published online: 21 MAY 2010
©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.
Pacing and Clinical Electrophysiology
Volume 33, Issue 8, pages 945–949, August 2010
How to Cite
MASSUMI, R. and SHEHATA, M. (2010), Doubling of the Ventricular Rate by Interpolated Junctional Extrasystoles Resembling Supraventricular Tachycardia. Pacing and Clinical Electrophysiology, 33: 945–949. doi: 10.1111/j.1540-8159.2010.02763.x
- Issue published online: 3 AUG 2010
- Article first published online: 21 MAY 2010
- Received September 24, 2009; revised December 24, 2009; accepted February 12, 2010.
In a study of seven cases of paroxysmal supraventricular tachycardia, it was noted that the fast rate was not caused by the mechanism of rapid firing, reentry, or dual atrioventricular nodal conduction but by an abrupt doubling of the rate by interpolation of junctional extrasystoles between adjacent sinus beats while the sinus mechanism remained undisturbed. Dual ventricular response to a single atrial depolarization was seriously considered in each case.
The intervals separating the junctional extrasystoles tended to be quite fixed, thus conforming to the pattern of junctional parasystole with an intrinsic rate very close to the rate of the dominant sinus rhythm. The paroxysms of tachycardia were transient, lasting a few seconds to 3.5 minutes. The onset and termination of the paroxysms were completely unpredictable and appeared unrelated to any change in the basic sinus rate or other identifiable mechanism. In only one case, case 7, the concept of dual ventricular response appeared tenable. However, as will be discussed later, the mechanism of junctional parasystole was found to be physiologically more acceptable. (PACE 2010; 945–949)