Delfaut P, Prakash A, Giorgberidze I, Munsif A N, Mathew P P, Krol R B, Saksena S
Arrhythmia and Pacemaker Service, Eastern Heart Institute, Passaic, NJ, USA.
Semin Interv Cardiol. 1997 Dec;2(4):219-25.
Atrial fibrillation (AF) has been recognized, with increasing concern, as a potentially disabling illness, occurring either as a symptom of many cardiac diseases or as an isolated disorder. It can independently contribute to mortality and morbidity and may have serious prognostic importance in acute or chronic cardiac disease. In patients with symptomatic drug refractory atrial fibrillation, ventricular rate control by atrioventricular nodal ablation or modification commonly results in pacemaker implantation. The concept of AF prevention by pacemaker therapy has been introduced in patients with bradycardia-tachycardia syndrome or vagally mediated bradycardia-dependent AF. In patients with sick sinus syndrome, atrial pacing has proved to be more effective than VVI pacing in maintaining the electrical stability of the atrium in long-term follow up. Recently, the development of new techniques of atrial pacing employing pacing at two atrial sites may improve the effectiveness of the AF prevention by pacemaker therapy. Dual-site right atrial pacing using overdrive stimulation activates simultaneously the high right atrium and the left atrium via the ostium of the coronary sinus. Two main mechanisms have been proposed to explain the favourable effect of this technique. One is the suppression of atrial premature beats initiating AF by the overdrive pacing. The second is the alteration of atrial activation pattern by preexcitation of the area of the coronary sinus ostium which permits earlier recovery of excitability in sites of atrial conduction delay. The combination of drug therapy and pacing is essential for effective AF control. We have hitherto studied 30 patients with single- and dual-site pacing. Single-site pacing was performed at the high right atrium or coronary sinus ostium. The dual-site pacing mode increased the arrhythmia-free intervals, decreased patients' arrhythmia-related symptoms and anti-arrhythmic drug use as compared to the period preceding institution of pacing and incrementally over conventional high right atrial pacing alone. A multicentre randomized trial, Dual-site Atrial Pacing for Prevention of Atrial Fibrillation (DAPPAF), evaluating three pacing modes (dual-site, single-site and support pacing), is now in progress.
心房颤动（AF）已日益受到关注，被视为一种可能导致功能障碍的疾病，它既可以是许多心脏疾病的症状，也可以是一种独立的病症。它可独立导致死亡率和发病率上升，在急性或慢性心脏疾病中可能具有重要的预后意义。对于有症状的药物难治性心房颤动患者，通过房室结消融或改良来控制心室率通常会导致起搏器植入。起搏器治疗预防心房颤动的概念已被引入到心动过缓-心动过速综合征或迷走神经介导的心动过缓依赖性心房颤动患者中。在病态窦房结综合征患者中，长期随访结果表明，心房起搏在维持心房电稳定性方面比VVI起搏更有效。最近，采用双心房部位起搏的新技术的发展可能会提高起搏器治疗预防心房颤动的有效性。使用超速刺激的双部位右心房起搏可通过冠状窦口同时激活右心房上部和左心房。已提出两种主要机制来解释该技术的有益效果。一种是通过超速起搏抑制引发心房颤动的房性早搏。另一种是通过冠状窦口区域的预激改变心房激动模式，这使得心房传导延迟部位的兴奋性能够更早恢复。药物治疗和起搏相结合对于有效控制心房颤动至关重要。我们此前研究了30例进行单部位和双部位起搏的患者。单部位起搏在右心房上部或冠状窦口进行。与起搏前相比，双部位起搏模式增加了无心律失常间期，减少了患者与心律失常相关的症状以及抗心律失常药物的使用，并且比单纯传统的右心房上部起搏有逐步改善。一项多中心随机试验，即预防心房颤动的双部位心房起搏（DAPPAF）试验，正在评估三种起搏模式（双部位、单部位和辅助起搏）。
