最小化心室起搏减少病态窦房结综合征患者心房颤动的发生

Minimizing ventricular pacing to reduce the occurence atrial fibrillation in sick sinus syndrome

目的探讨最小化心室起搏对病态窦房结综合征（病窦综合征）患者心房颤动（房颤）发生的影响。方法入选2003年4月至2008年4月因病窦综合征植入DDD起搏器的患者112例，随机、单盲分为最小化心室起搏组56例（A组），和传统双心腔起搏组56例（B组），分别于3、6个月进行随访，以后每年1次，每次随访内容包括病史询问、起搏器程控、超声心动图。主要观察指标为房颤发生率，次要观察指标为超声心动图（包括左心房内径、左心室舒张末内径和左心室射血分数）和因心力衰竭再入院情况。结果平均随访时间为（33．7±17．1）个月，与B组相比，A组的心室起搏平均比例显著减少（10．1％vs92．3％，P〈0．001），但两组的心房起搏平均比例相近（73．6％vs72．8％，P=0．98）。B组累计房颤发生率明显低于A组（RR=0．65，95％可信区间0．59～0．93，P=0．015）。与植入前相比，A组各阶段超声心动图变化差异无统计学意义；而B组左心房内径逐渐增大。术后2年起，B组左心房内径与植入前相比，或与同期的A组相比，差异有统计学意义。结论右心室心尖部起搏使病窦综合征患者房颤发生率增加，左心房内径增大。因此，对房室传导正常的病窦综合征患者，建议最小化心室起搏，鼓励心室自身传导。

Objective To explore the effects of minimizing ventricular pacing on the incidence of atrial fibrillation（ AF） in patients with sick sinus syndrome（SSS）. Methods Patients with SSS who were implanted with DDD pacemakers from April 2003 to April 2008 were enrolled. They were randomized to minimize ventricular pacing group（ A group 56 cases）and conventional dual-chamber pacing group （B group 56 cases ）, and were followed up at 3 month, and 6 month after implantation and then annually. Pacemaker interrogation, electrocardiogram,echocardiography were performed during follow-up. The main outcome measures was occurrence of atrial fibrillation. The second outcome measures were the changes in cardiac sizes and function measured by echocardiography（ Including the left atrial diameter,left ventricular end-diastolic diameter and left ventricular ejection fraction） and the state of rehospitalizing for heart failure. Results Mean follow-up time was （33.7 ± 17. 1 ）months. The mean proportion of ventricular pacing significantly decreased in A group than in B group（10. 1% vs92. 3%, P 〈 0. 001 ）, but the mean proportion of atrial pacing were similar in two groups （73.6% vs72. 8%, P = 0.98 ）. Cumulative paroxysmal atrial fibrillation was significantly less in A group than in B group（ RR =0. 65,95% CI 0. 59 - 0. 93, P =0. 015 ）. Compared with preimplantation, left atrial （ LA ）, ventricular size and cardiac function were not changed significantly at each follow-up in A group. But two years later, the left atrial diameter was significantly enlarged in B group compared with A group. The left ventricular size and cardiac function were not statistically changed between two groups. Conclusions Right ventricular apical pacing could lead to more atrial fibrillation events and enlarge LA diameter. In patients with SSS and normal atrioventricular conduction, a more careful selection of minimizing ventricular pacing is safe and feasible, and should be advocated.