MODE SELECTION TRIAL IN SINUS NODE DYSFUNCTION (MOST)

MOST项目是美国国立卫生研究院（nih）赞助的一项多中心、为期5年的研究，纳入2000名患者，其设计有三个不可分割且同等重要的目标：1)确定所有病窦综合征（SSS）患者的双室、速率调节（DDDR）起搏的初始策略是否能提高无事件生存率；2)确定随机接受DDDR起搏的患者是否比随机接受心室速率调节（VVIR）起搏的患者有更好的生活质量；3)在1.5-4.5年的纵向随访后，确定DDDR起搏是否比VVIR起搏更具成本效益。该研究的主要终点将是由卒中和全因死亡率组成的复合临床终点。总死亡率和由首次发生卒中、心力衰竭住院或死亡组成的复合终点将构成重要的次要临床终点。一项生活质量（QOL）亚研究正在对随机选择的1400名患者进行，以提供数据来扭转目前似乎限制妇女和老年人的实践模式。这项生活质量研究的目标是女性和老年人，以确定DDDR起搏在这两个亚组中是否更优。因此，MOST旨在确定DDDR起搏器的较高初始成本是否可以通过预防不良事件和改善生活质量（患者利益）来抵消，以及所有SSS患者的DDDR起搏是否包括社会效益（平衡DDDR起搏增加的技术成本与潜在的长期临床节省）。

The MOST project is an NIH-sponsored, multicenter, 5-year study in 2000 patients, designed with three indivisible and equally important aims: 1) to determine whether an initial strategy for dual-chamber, rate-modulated (DDDR) pacing in all patients with sick sinus syndrome (SSS) improves event-free survival; 2) to determine whether patients randomized to DDDR pacing have a better quality of life than do patients randomized to ventricular rate-modulated (VVIR) pacing, and 3) to determine if, after 1.5-4.5 years of longitudinal followup, DDDR pacing is more cost-effective than VVIR pacing. The primary endpoint of the study will be a composite clinical endpoint consisting of stroke and all-cause mortality. Total mortality and a composite endpoint consisting of the first occurrence of stroke, heart failure hospitalization, or death will constitute important secondary clinical endpoints. A Quality of Life (QOL) substudy is being conducted in a randomly selected subset of 1400 patients, to provide data to reverse current practice patterns which appear to restrict women and the aged. This QOL study targets women and the elderly to determine if DDDR pacing is superior in these two subgroups. Thus, MOST seeks to determine if the greater initial cost of DDDR pacemakers is offset by preventing adverse events and by improvement of QOL (patient benefits), and if DDDR pacing of all patients with SSS includes societal benefits (balancing the increased technological costs of DDDR pacing with potential long-term clinical savings).