Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge; Cardiology Department, West Suffolk Hospital NHS Foundation Trust, Bury St. Edmunds.
Department of Cardiology, Papworth Hospital NHS Foundation, Cambridge University Health Partners, Papworth Everard.
J Am Soc Echocardiogr. 2018 Sep;31(9):983-991. doi: 10.1016/j.echo.2018.03.011. Epub 2018 May 24.
The aim of this study was to determine whether assessment of left atrial (LA) function helps identify patients at risk for early deterioration during follow-up with mitral valve prolapse and mitral regurgitation.
Patients with moderate to severe mitral regurgitation but no guideline-based indications for surgery were retrospectively identified from a dedicated clinical database. Maximal and minimal LA volumes were used to derive total LA emptying fraction ([maximal LA volume - minimal LA volume]/maximal L volume × 100%). Average values of peak contractile, conduit, and reservoir strain were obtained using two-dimensional speckle-tracking imaging. The study outcome was time to mitral surgery.
One hundred seventeen patients were included; median follow-up was 18 months. Sixty-eight patients underwent surgery. Receiver operating characteristic curves were used to derive optimal cutoffs for TLAEF (>50.7%) and strain (reservoir, >28.5%; contractile, >12.5%). Using Cox analysis, TLAEF and contractile, reservoir, and conduit strain were univariate predictors of time to event. After multivariate analysis, TLAEF (hazard ratio, 2.59; P = .001), reservoir strain (hazard ratio, 3.06; P < .001), and contractile strain (hazard ratio, 2.01; P = .022) remained independently associated with events, but conduit strain did not. Using Kaplan-Meier curves, event-free survival was considerably improved in patients with values above the derived thresholds (TLAEF: 1-year survival, 78 ± 5% vs 28 ± 8%; 3-year survival, 68 ± 6% vs 13 ± 5%; P < .001 for both; reservoir strain: 1-year survival, 79 ± 5% vs 29 ± 7%; 3-year survival, 67 ± 6% vs 15 ± 6%; P < .001 for both; contractile strain: 1-year survival, 80 ± 5% vs 41 ± 7%; 3-year survival, 69 ± 6% vs 24 ± 6%; P < .001 for both).
LA function is independently associated with surgery-free survival in patients with mitral valve prolapse and moderate to severe mitral regurgitation. Quantitative assessment of LA function may have clinical utility in guiding early surgical intervention in these patients.
本研究旨在确定左心房（LA）功能评估是否有助于识别二尖瓣脱垂伴二尖瓣反流患者在随访过程中早期病情恶化的风险。
从专门的临床数据库中回顾性确定中度至重度二尖瓣反流但无手术适应证的患者。使用最大和最小 LA 容积来推导总 LA 排空分数（[最大 LA 容积-最小 LA 容积]/最大 L 容积×100%）。使用二维斑点追踪成像获得峰值收缩、传导和储层应变的平均值。研究结果为二尖瓣手术时间。
共纳入 117 例患者；中位随访时间为 18 个月。68 例患者接受了手术。使用接收器工作特征曲线得出 TLAEF（>50.7%）和应变（储层，>28.5%；收缩，>12.5%）的最佳截断值。使用 Cox 分析，TLAEF 和收缩、储层和传导应变是时间事件的单变量预测因子。多变量分析后，TLAEF（风险比，2.59；P=0.001）、储层应变（风险比，3.06；P<0.001）和收缩应变（风险比，2.01；P=0.022）与事件仍然独立相关，但传导应变则不然。使用 Kaplan-Meier 曲线，在获得的阈值以上，患者的无事件生存显著改善（TLAEF：1 年生存率，78±5%比 28±8%；3 年生存率，68±6%比 13±5%；均 P<0.001；储层应变：1 年生存率，79±5%比 29±7%；3 年生存率，67±6%比 15±6%；均 P<0.001；收缩应变：1 年生存率，80±5%比 41±7%；3 年生存率，69±6%比 24±6%；均 P<0.001）。
在二尖瓣脱垂伴中度至重度二尖瓣反流患者中，LA 功能与手术无生存相关。LA 功能的定量评估可能在指导这些患者的早期手术干预方面具有临床应用价值。
