Correspondence
Minimizing Ventricular Pacing in Sinus-Node Disease
N Engl J Med 2007; 357:2733-2734December 27, 2007
- Article
To the Editor:
Sweeney et al. (Sept. 6 issue)1 report on their study of a strategy to minimize ventricular pacing in patients with sinus-node disease. Although mainly a semantic issue, the patients who were randomly assigned to “conventional” dual-chamber pacing in the study were not receiving what is considered the current recommended pacing strategy for patients with sinus-node disease and intact atrioventricular conduction, a predominantly atrial pacing strategy that allows atrioventricular conduction to maximally preserve normal ventricular conduction.2 Dual-chamber, rate-adaptive (DDDR) pacing with a short atrioventricular delay was previously considered physiologic but has been shown to lead to a higher risk of atrial fibrillation and reduced myocardial blood flow as compared with atrial, rate-adaptive pacing.3,4 The study by Sweeney et al. strengthens the notion that minimizing ventricular pacing is preferred. Their strategy allows a maximum sensed and paced atrioventricular delay of 300 and 360 msec, respectively,5 but ventricular pacing was still present. DDDR with a fixed atrioventricular delay of 300 msec has been shown to be ineffective in eliminating ventricular pacing in one third of subjects and may also lead to arrhythmias related to retrograde atrioventricular conduction.6 Therefore, the optimal pacing strategy for patients with sinus-node disease remains to be determined.
Norman C. Wang, M.D.
Rod Passman, M.D.
Jeffrey J. Goldberger, M.D.
Northwestern University, Chicago, IL 60611Dr. Passman reports receiving research support from Medtronic. No other potential conflict of interest relevant to this letter was reported.
6 References1
Sweeney MO ,Bank AJ ,Nsah E , et al. Minimizing ventricular pacing to reduce atrial fibrillation in sinus-node disease. N Engl J Med 2007;357:1000-1008
Full Text | Web of Science | Medline2
Sweeney MO ,Prinzen FW . A new paradigm for physiologic ventricular pacing. J Am Coll Cardiol 2006;47:282-288
CrossRef | Web of Science | Medline3
Nielsen JC ,Kristensen L ,Andersen HR ,Mortensen PT ,Pedersen OL ,Pedersen AK . A randomized comparison of atrial and dual-chamber pacing in 177 consecutive patients with sinus syndrome: echocardiographic and clinical outcome. J Am Coll Cardiol 2003;42:614-623
CrossRef | Web of Science | Medline4
Nielsen JC ,Bottcher M ,Nielsen TT ,Pedersen AK ,Andersen HR . Regional myocardial blood flow in patients with sick sinus syndrome randomized to long-term single chamber atrial or dual chamber pacing -- effect of pacing mode and rate. J Am Coll Cardiol 2000;35:1453-1461
CrossRef | Web of Science | Medline5
Melzer C ,Sowelam S ,Sheldon TJ , et al. Reduction of right ventricular pacing in patients with sinus node dysfunction using an enhanced search AV algorithm. Pacing Clin Electrophysiol 2005;28:521-527
CrossRef | Web of Science | Medline6
Nielsen JC ,Pedersen AK ,Mortensen PT ,Andersen HR . Programming a fixed long atrioventricular delay is not effective in preventing ventricular pacing in patients with sick sinus syndrome. Europace 1999;1:113-120
CrossRef | Web of Science | Medline
Author/Editor Response
We believed that retrospective analyses1 and small prospective studies2 linking a high frequency of ventricular pacing to increased risks of atrial fibrillation and heart failure in patients with sinus node disease, though compelling, did not meet the highest level of clinical evidence necessary to broadly inform changes in clinical practice. Furthermore, conventional dual-chamber pacing, despite a high frequency of “forced” ventricular pacing,1 had not been proven inferior to any alternative pacing strategy.3 Accordingly, our study was designed to definitively test the hypothesis that high-frequency ventricular pacing, despite continuous atrioventricular synchronization, may increase the risk of atrial fibrillation in patients with sinus-node disease, as compared with the best available techniques for reducing ventricular pacing when the trial was initiated in 2002. Now that it has been established that less ventricular pacing is better, perhaps additional studies will be necessary to establish the best approach. Newer pacing strategies developed specifically to achieve this goal, such as “managed ventricular pacing,” have been shown to reduce the frequency of ventricular pacing to 5% or lower in more than 90% of patients, without the functional limitations of dynamic or fixed long atrioventricular intervals.3-5
5 ReferencesMichael O. Sweeney, M.D.
Brigham and Women's Hospital, Boston, MA 02115
mosweeney@partners.org Gervasio A. Lamas, M.D.
Mt. Sinai Medical Center, Miami Beach, FL 331401
Sweeney MO ,Hellkamp AS ,Ellenbogen KA , et al. Adverse effect of ventricular pacing on heart failure and atrial fibrillation among patients with normal baseline QRS duration in a clinical trial of pacemaker therapy for sinus node dysfunction. Circulation 2003;107:2932-2937
CrossRef | Web of Science | Medline2
Nielsen JC ,Kristensen L ,Andersen HR ,Mortensen PT ,Pedersen OL ,Pedersen AK . A randomized comparison of atrial and dual-chamber pacing in 177 consecutive patients with sick sinus syndrome: echocardiographic and clinical outcome. J Am Coll Cardiol 2003;42:614-623
CrossRef | Web of Science | Medline3
Sweeney MO . Minimizing right ventricular pacing: a new paradigm for cardiac pacing in sinus node dysfunction. Am Heart J 2007;153:Suppl:34-43
CrossRef | Web of Science | Medline4
Sweeney MO ,Shea JB ,Fox V , et al. Randomized trial of a new atrial-based minimal ventricular pacing mode in dual-chamber implantable cardioverter-defibrillators. Heart Rhythm 2004;1:160-167
CrossRef | Web of Science | Medline5
Sweeney MO ,Ellenbogen KA ,Betzold R , et al. Multicenter, prospective, randomized safety and efficacy study of a new atrial-based managed ventricular pacing mode (MVP) in dual chamber ICDs. J Cardiovasc Electrophysiol 2005;16:811-817
CrossRef | Web of Science | Medline
