[AF-FORUM] EXPERTS ASK, EXPERTS ANSWER. XVI. To Dr. Perkiomaki from Dr. R. Fernandez from Mexico

[Atrial Fibrillation Symposium]

Dear Dr. Juha Perkiomaki,
The text below is an interesting study that analyzed the incidence of "dual
tachycardia" as they called the presence of VT/VF preceded by atrial
tachycardia or else AF, in patients who received ICD therapy.
I send the pdf of the article and the abstract.

Dr. JAIRO ARMANDO RODRIGUEZ FERNANDEZ
CARDIOLOGÍA CLÍNICA
HOSPITAL GENERAL DE ZONA 24, IMSS
www.geocities.com/heartjairo/cardio

Do atrial tachyarrhythmias beget ventricular tachyarrhythmias in defibrillator 
recipients?
Kenneth M. Stein, MD, FACC*,*, David E. Euler, PhD, Rahul Mehra, PhD, 
Karlheinz Seidl, MD, David J. Slotwiner, MD*, Suneet Mittal, MD, FACC*, 
Steven M. Markowitz, MD, FACC*, Bruce B. Lerman, MD, FACC* Jewel AF
Worldwide Investigators
* Division of Cardiology, Department of Medicine, Cornell University Medical
College, New York, New York, USA
 Medtronic Inc., Minneapolis, Minnesota, USA
 Herzentrum Ludwigshafen, Ludwigshafen, Germany
Manuscript received July 30, 2001; revised manuscript received March 28,
2002, accepted April 17, 2002.

* Reprint requests and correspondence: Dr. Kenneth M. Stein, Division of 
Cardiology, Starr-4, The New York Hospital, 525 East 68th Street, New York,
New York 10021, USA.
kstein at mail.med.cornell.edu

OBJECTIVES: This study was designed to analyze the incidence of "dual 
tachycardia"-ventricular tachycardia (VT) or ventricular fibrillation (VF) 
preceded by paroxysmal atrial tachycardia (AT) or atrial fibrillation
(AF)-in patients receiving dual-chamber implantable cardioverter
defibrillators (ICDs).
BACKGROUND: Paroxysmal AT/AF occurs commonly in patients who receive ICDs
for the treatment of life-threatening VT/VF. Although AF is associated with
an adverse prognosis in the setting of structural heart disease, the
relationship between AT/AF and VT/VF is unclear.
METHODS: We followed 537 patients undergoing implantation of the Jewel AF
ICD (Model 7250, Medtronic, Minneapolis, Minnesota) for 11.4 ± 8.2 months.
These included 398 patients with a history of at least two episodes of AT or
AF during the preceding year as well as 139 patients enrolled because of
VT/VF alone.
RESULTS: There were 233 dual tachycardia episodes in 45 patients during
follow-up. Overall, 8.9% of episodes detected as VT/VF were dual
tachycardias, and 20.3% of patients with VT/VF had at least one dual
tachycardia episode. The median duration of AT/AF preceding the first VT/VF
detection was 1.09 h (25% to 75% quartile 0.24 to 33.4 h). When AT/AF
continued between two consecutive VT/VF detections, the median
interdetection interval was 11 min. When AT/AF terminated either because of
a ventricular therapy or spontaneously, the median interdetection interval
was prolonged to 71 h (p < 0.001)
CONCLUSIONS: Dual tachycardia is common in ICD recipients with a history of
AT/AF. The duration of AT/AF preceding the first VT/VF detection is 1 h
about 50% of the time. Termination of the AT/AF significantly delays the
time to the next VT/VF detection.

> Dr. Juha Perkiömäki from Finland asks
>
> - When can atrial fibrillation result in ventricular tachyarrhythmia?
>
> Dr. Bernard Gersh from U.S.A. answers
>
> - I suspect that there is very little data upon which to answer this
> question. Certainly in pts with rapid AF and WPW this could
> degenerate into VF.
> I suspect that the same could happen in pts with Hypertrophic
> cardiomyopathy/ aortic stenosis etc but do not know the frequency. I
> also suspect that in some pts with severe CAD or MI rapid atrial
> fibrillation could precipitate ischemic arrhythmias.

-- 
Dr. Sergio Dubner
President

Dr. Edgardo Schapachnik
Director