Background: Cardiac resynchronization therapy (CRT) has been demonstrated to improve heart failure (HF) symptoms, reverse LV remodeling, and reduce mortality and HF hospitalization (HFH) in patients with a reduced left ventricular (LV) ejection fraction (LVEF). Prior studies examining outcomes based on right ventricular (RV) lead position among CRT patients have provided mixed results. We performed a systematic review and meta-analysis of randomized controlled trials and prospective observational studies comparing RV apical (RVA) and non-apical (RVNA) lead position in CRT.

Methods: Our meta-analysis was constructed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews and meta-analyses. We searched EMBASE and MEDLINE. Eligible studies reported on at least one of the following outcomes of interest: all-cause mortality, the composite endpoint of death and first HFH hospitalization, change in LVEF, New York Heart Association (NYHA) class improvement, and change in LV end systolic volume (LVESV). We performed meta-analysis summaries using a DerSimonian-Laird random-effects model and conservatively used the Knapp-Hartung approach to adjust the standard errors of the estimated model coefficients.

Results: We included nine studies representing a total of 1832 patients. Of those, 1318 (72%) patients had RVA lead placement and 514 (28%) had RVNA lead placement. The mean age of patients was 65.5 ± 4.4 years, and they were predominantly men (69%–97%). There was no statistically significant difference in all-cause mortality by RVA vs. RVNA (OR = 0.77, 95% CI 0.32–1.89; I² = 16.7%, p = 0.31), or in the combined endpoint of all-cause mortality and first HFH (OR 0.88, 95% CI 0.62–1.25; I² = 0%, p = 0.84). Also, there was no difference between RVA and RVNA for NYHA class improvement (OR = 1.03, 95% CI 0.9–1.17; I² = 0%, p = 0.99), change in LVEF (mean difference (MD) = 1.33, 95% CI -1.45 to 4.10; I² = 47%; p = 0.093), and change in LVESV (MD = −1.11, 95% CI −3.34 to 1.12; I² = 0%; p = 0.92).

Conclusion: This meta-analysis shows that in CRT pacing, RV lead position does not appear to be associated with clinical outcomes or LV reverse remodeling. Further studies should focus on the relationship of RV lead vis-à-vis LV lead location, and its clinical importance.

背景：心脏再同步治疗 (CRT) 已被证明可以改善左心室 (LV) 射血分数 (LVEF) 降低的患者的心力衰竭 (HF) 症状、逆转 LV 重构并降低死亡率和 HF 住院率 (HFH)。先前基于 CRT 患者右心室 (RV) 导线位置检查结果的研究提供了不同的结果。我们对比较 CRT 中 RV 心尖 (RVA) 和非心尖 (RVNA) 铅位置的随机对照试验和前瞻性观察研究进行了系统评价和荟萃分析。

方法：我们的荟萃分析是根据系统评价和荟萃分析的首选报告项目 (PRISMA) 系统回顾和荟萃分析指南构建的。我们搜索了 EMBASE 和 MEDLINE。符合条件的研究至少报告了以下感兴趣的结果之一：全因死亡率、死亡和首次 HFH 住院的复合终点、LVEF 变化、纽约心脏协会 (NYHA) 分级改善和 LV 收缩末期容积变化(LVESV)。我们使用 DerSimonian-Laird 随机效应模型进行荟萃分析总结，并保守地使用 Knapp-Hartung 方法来调整估计模型系数的标准误差。

结果：我们纳入了九项研究，共代表 1832 名患者。其中，1318 名 (72%) 患者放置了 RVA 导线，514 名 (28%) 患者放置了 RVNA 导线。患者的平均年龄为 65.5 ± 4.4 岁，主要为男性 (69%–97%)。RVA 与 RVNA 的全因死亡率（OR = 0.77，95% CI 0.32–1.89；I ² = 16.7%，p = 0.31）或全因死亡率和第一次 HFH（OR 0.88，95% CI 0.62–1.25；I ² = 0%，p = 0.84）。此外，RVA 和 RVNA 在 NYHA 等级改善方面没有差异（OR = 1.03，95% CI 0.9–1.17；I ² = 0%，p= 0.99)、LVEF 变化（平均差 (MD) = 1.33，95% CI -1.45 至 4.10；I ² = 47%；p = 0.093）和 LVESV 变化（MD = -1.11，95% CI -3.34到 1.12；I ² = 0%；p = 0.92）。

结论：这项荟萃分析表明，在 CRT 起搏中，RV 导线位置似乎与临床结果或 LV 反向重构无关。进一步的研究应侧重于 RV 导线与 LV 导线位置的关系及其临床重要性。