(Circulation. 2001;103:e130.)
© 2001 American Heart Association, Inc.
Correspondence |
Predictors of Atrial Fibrillation After Conventional and Beating Heart Coronary Surgery
Division of Cardiovascular Disease, St Vincent’s Hospital at Worcester Medical Center, 20 Worcester Center Blvd, Worcester, MA 01608
To the Editor:
Ascione and colleagues1 contribute a valuable prospective, randomized study of perioperative predictors of atrial fibrillation after coronary artery surgery and conclude that cardiopulmonary bypass, including cardioplegic arrest, is the main independent predictor of fibrillation. It is odd, however, that the 16 well-matched baseline characteristics for those on-pump and off-pump did not include the presence of interatrial block on the routine 12-lead ECG. This is a well-known predictor of atrial fibrillation and flutter.2 3 4 Indeed, in this general hospital, my colleagues and I demonstrated this association in 41% of consecutive patients in sinus rhythm (in press). The mean age of Ascione et al’s patients in both groups was 63 years, and this easily recognized electrocardiographic finding is especially prevalent in older patients. Perhaps the authors could look at their groups again and inform Circulation’s readers whether the groups were balanced for interatrial block.
References
1.
Ascione R,
Caputo M, Calori G, et al. Predictors of atrial fibrillation after
conventional and beating heart coronary surgery.
Circulation. 2000;102:1530–1535.
2. Bayes de Luna A, Cladellas M, Cafferas F, et al. Interatrial blocks: their relationship with atrial tachyarrhythmias. In: Levy S, ed. Cardiac Arrhythmias. New York: Futura; 1984:217–229.
3.
Leier CV, Meacham
JA, Shaal SF. Prolonged atrial conduction: a major predisposing factor
for the development of atrial flutter.
Circulation. 1978;57:213–216.
4. Ramsaran EK, Spodick DH. Electromechanical delay in the left atrium as a consequence of interatrial block. Am J Cardiol. 1996;50:1132–1134.
Response
Bristol Heart Institute, University of Bristol, Bristol Royal Infirmary, Bristol BS2 8HW, England,
Epidemiology Unit, San Raffaele Hospital, Milan, Italy
We thank Dr Spodick for his interesting comments. The
original analysis of baseline characteristics in our study
populationR1 did not include
the presence of interatrial block. After reading Dr Spodick’s
comments, we asked an independent cardiologist at our institution to
review all the preoperative ECGs from the same groups of
patientsR1 to investigate the
potential role of P-wave prolongation as a predictor of atrial
fibrillation. Because a diagnosis of interatrial block on the routine
12-lead ECG was not possible, we evaluated intraatrial conduction time
by measuring P-wave duration. To evaluate any relation between P-wave
prolongation and the occurrence of atrial fibrillation, the
analysis was performed using 2 different end points for P-wave
duration (140 and 120 ms). The result of this new analysis
showed that only 3 patients (1.5%) had a preoperative P-wave duration
140 ms, and none of them developed postoperative atrial fibrillation.
Furthermore, 32 patients (16%) had a P-wave duration 120 ms, and
only 5 of these patients had postoperative atrial fibrillation (all
were in the on-pump group).
This analysis shows that the incidence of
interatrial block, if defined by a P-wave duration 140 ms, in
selected patients undergoing coronary artery surgery is far
less than the 41% reported by Spodick in his unpublished observations.
Furthermore, in our study, P-wave prolongation was not a predictor of
postoperative atrial fibrillation.
References
1. Ascione R, Caputo M, Calori G, et al. Predictors of atrial fibrillation after conventional and beating heart coronary surgery. Circulation. 2000;102:1530–1535.
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