December 1, 2004
By Ashley
Starkweather, B.S. and Asher Kimchi M.D.
Bordeaux-Pessac,
France – In a study of 58 patients with atrial fibrillation and
congestive heart failure, catheter ablation was found to improve
cardiac function, quality of life, and exercise capacity by
restoring and maintaining sinus rhythm. The results of this
study were published by Li-Fern Hsu, M.B., B.S., from the
Hopital Cardiologique du Haut-Leveque in Bordeaux-Pessac,
France, in the December 2, 2004 issue of the New England Journal
of Medicine.
Congestive heart
failure and atrial fibrillation often coexist, each promoting
the existence of the other. When trying to maintain sinus rhythm
in patients with atrial fibrillation complicated by congestive
heart failure, antiarrhythmic drugs often prove to have low
efficacy or potentially harmful side effects. This study
evaluated the effects of restoring and maintaining sinus rhythm
via catheter ablation in this subgroup of patients in order to
avoid the use of antiarrhythmic drugs.
In the study, investigators enrolled 58 consecutive patients
with congestive heart failure of NYHA Class II who were
undergoing curative ablation for atrial fibrillation that was
resistant to at least two antiarrhythmic drugs and had a left
ventricular ejection fraction of less than 45 percent. These
patients were matched for age, sex, and classification of atrial
fibrillation with procedural controls during the same time
period from March 2001 to March 2004.
Patients were admitted two days prior to ablation and oral
anticoagulants were stopped on admission. Anti-arrhythmic drugs
were stopped prior to the procedure. Heart rate and rhythm were
monitored by 48 hour ambulatory electrocardiography, and
transesophageal echocardiography was performed to rule out
atrial thrombi prior to ablation. Transthoracic echocardiography
was used to assess left ventricle size and function. The
ablation procedure aimed to electrically isolate all the
pulmonary veins and to create a complete obstacle to electrical
conduction. Post-ablation, anticoagulation therapy was
reinitiated, and patients were monitored for three days.
Patients were also tested for baseline exercise capacity on a
bicycle stress test.
Follow-up required rehospitalization at 1, 3, 6, and 12 months
after the last ablation procedure, and consisted of clinical
interviews, 48-hour electrocardiographic monitoring, transthoracic
echocardiography, and exercise testing. Anticoagulation was
discontinued if sinus rhythm was maintained for three to six
months. Symptoms and quality of life were assessed at 3 and 12
months.
The results of the study showed an improvement in cardiac
function after establishing and maintaining sinus rhythm from
catheter ablation. NYHA congestive heart failure class improved
from a mean of 2.3 to 1.4 at the one month mark, and stayed at
that level. Exercise time and capacity increased significantly,
from mean time of 11 minutes to 15 minutes (P<0.001) and mean
maximal capacity from 123 to 144 W (P<0.001) during the
follow-up period. The left ventricular ejection fraction
increased by a mean of 21 percent, with the greatest improvement
seen in the first three months. The Symptom Checklist-Frequency
and Severity scores and SF-36 quality of life measures improved
significantly as well.
In conclusion, after catheter ablation for atrial fibrillation,
long term restoration of sinus rhythm, without the use of
antiarrhythmic drugs, resulted in significant improvement in
left ventricular function, exercise capacity, symptoms, and
quality of life. Furthermore, while this study did not directly
assess the effect on mortality, because a reduced ejection
fraction is an important predictor of mortality, the significant
improvement in left ventricular function after ablation could be
important in improving survival.
Co-authors: Pierre Jais, M.D.; Prashanthan Sanders, M.B., B.S.,
Ph.D.; Stephane Garrigue, M.D., Ph.D.; Meleze Hocini, M.D.;
Frederic Sacher, M.D.; Yoshihide Takahashi, M.D.; Martin Rotter,
M.D.; Jean-Luc Pasquie, M.D., Ph.D.; Christophe Scavee, M.D.;
Pierre Bordachar, M.D.; Jacques Clementy, M.D.; and Michael
Haissaguerre, M.D.
|