Sweeney Michael O, Bank Alan J, Nsah Emmanuel, Koullick Maria, Zeng Qian Cathy, Hettrick Douglas, Sheldon Todd, Lamas Gervasio A
Cardiac Arrhythmia Service, Brigham and Women's Hospital, Boston, MA 02115, USA.
N Engl J Med. 2007 Sep 6;357(10):1000-8. doi: 10.1056/NEJMoa071880.
Conventional dual-chamber pacing maintains atrioventricular synchrony but results in high percentages of ventricular pacing, which causes ventricular desynchronization and has been linked to an increased risk of atrial fibrillation in patients with sinus-node disease.
We randomly assigned 1065 patients with sinus-node disease, intact atrioventricular conduction, and a normal QRS interval to receive conventional dual-chamber pacing (535 patients) or dual-chamber minimal ventricular pacing with the use of new pacemaker features designed to promote atrioventricular conduction, preserve ventricular conduction, and prevent ventricular desynchronization (530 patients). The primary end point was time to persistent atrial fibrillation.
The mean (+/-SD) follow-up period was 1.7+/-1.0 years when the trial was stopped because it had met the primary end point. The median percentage of ventricular beats that were paced was lower in dual-chamber minimal ventricular pacing than in conventional dual-chamber pacing (9.1% vs. 99.0%, P<0.001), whereas the percentage of atrial beats that were paced was similar in the two groups (71.4% vs. 70.4%, P=0.96). Persistent atrial fibrillation developed in 110 patients, 68 (12.7%) in the group assigned to conventional dual-chamber pacing and 42 (7.9%) in the group assigned to dual-chamber minimal ventricular pacing. The hazard ratio for development of persistent atrial fibrillation in patients with dual-chamber minimal ventricular pacing as compared with those with conventional dual-chamber pacing was 0.60 (95% confidence interval, 0.41 to 0.88; P=0.009), indicating a 40% reduction in relative risk. The absolute reduction in risk was 4.8%. The mortality rate was similar in the two groups (4.9% in the group receiving dual-chamber minimal ventricular pacing vs. 5.4% in the group receiving conventional dual-chamber pacing, P=0.54).
Dual-chamber minimal ventricular pacing, as compared with conventional dual-chamber pacing, prevents ventricular desynchronization and moderately reduces the risk of persistent atrial fibrillation in patients with sinus-node disease. (ClinicalTrials.gov number, NCT00284830 [ClinicalTrials.gov].).
传统双腔起搏可维持房室同步,但心室起搏比例较高,会导致心室失同步,并与窦房结疾病患者发生心房颤动的风险增加有关。
我们将1065例窦房结疾病、房室传导正常且QRS间期正常的患者随机分组,分别接受传统双腔起搏(535例患者)或使用旨在促进房室传导、保留心室传导并防止心室失同步的新型起搏器功能进行双腔最小化心室起搏(530例患者)。主要终点是持续心房颤动的发生时间。
由于试验达到主要终点而停止时,平均(±标准差)随访期为1.7±1.0年。双腔最小化心室起搏时起搏的心室搏动的中位数百分比低于传统双腔起搏(9.1%对99.0%,P<0.001),而两组起搏的心房搏动百分比相似(71.4%对70.4%,P=0.96)。110例患者发生了持续心房颤动,传统双腔起搏组有68例(12.7%),双腔最小化心室起搏组有42例(7.9%)。与传统双腔起搏患者相比,双腔最小化心室起搏患者发生持续心房颤动的风险比为0.60(95%置信区间,0.41至0.88;P=0.009),表明相对风险降低了40%。风险的绝对降低率为4.8%。两组的死亡率相似(接受双腔最小化心室起搏组为4.9%,接受传统双腔起搏组为5.4%,P=0.54)。
与传统双腔起搏相比,双腔最小化心室起搏可防止心室失同步,并适度降低窦房结疾病患者发生持续心房颤动的风险。(临床试验注册号,NCT00284830 [ClinicalTrials.gov]。)