Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota.
Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota.
J Am Coll Cardiol. 2020 Aug 11;76(6):637-649. doi: 10.1016/j.jacc.2020.06.029.
Mitral valve prolapse (MVP) is often considered benign but recent suggestion of an arrhythmic MVP (AMVP) form remains incompletely defined and uncertain.
This study determined ventricular arrhythmia prevalence, severity, phenotypical context, and independent impact on outcome in patients with MVP.
A cohort of 595 (age 65 ± 16 years; 278 women) consecutive patients with MVP and comprehensive clinical, arrhythmia (24-h Holter monitoring) and Doppler-echocardiographic characterization, was identified. Long-term outcomes were analyzed.
Ventricular arrhythmia was frequent (43% with at least ventricular ectopy ≥5%), most often moderate (ventricular tachycardia [VT]; 120 to 179 beats/min) in 27%, and rarely severe (VT ≥180 beats/min) in 9%. Presence of ventricular arrhythmia was associated with male sex, bileaflet prolapse, marked leaflet redundancy, mitral annulus disjunction (MAD), a larger left atrium and left ventricular end-systolic diameter, and T-wave inversion/ST-segment depression (all p ≤ 0.001). Severe ventricular arrhythmia was independently associated with presence of MAD, leaflet redundancy, and T-wave inversion/ST-segment depression (all p < 0.0001) but not with mitral regurgitation severity or ejection fraction. Overall mortality after arrhythmia diagnosis (8 years; 13 ± 2%) was strongly associated with arrhythmia severity (8 years; 10 ± 2% for no/trivial, 15 ± 3% for mild and/or moderate, and 24 ± 7% for severe arrhythmia; p = 0.02). Excess mortality was substantial for severe arrhythmia (univariate hazard ratio [HR]: 2.70; 95% confidence interval [CI]: 1.27 to 5.77; p = 0.01 vs. no/trivial arrhythmia), even after it was comprehensively adjusted, including for MVP characteristics (adjusted HR: 2.94; 95% CI: 1.36 to 6.36; p = 0.006) and by time-dependent analysis (adjusted HR: 3.25; 95% CI: 1.56 to 6.78; p = 0.002). Severe arrhythmia was also associated with higher rates of mortality, defibrillator implantation, VT ablation (adjusted HR: 4.68; 95% CI: 2.45 to 8.92; p < 0.0001), particularly under medical management (adjusted HR: 5.80; 95% CI: 2.75 to 12.23; p < 0.0001), and weakly post-mitral surgery (adjusted HR: 3.69; 95% CI: 0.93 to 14.74; p = 0.06).
In this large cohort of patients with MVP, ventricular arrhythmia by Holter monitoring was frequent but rarely severe. AMVP was independently associated with phenotype dominated by MAD, marked leaflet redundancy, and repolarization abnormalities. Long-term severe arrhythmia was independently associated with notable excess mortality and reduced event-free survival, particularly under medical management. Therefore, AMVP is a clinical entity strongly associated with outcome and warrants careful risk assessment and well-designed clinical trials.
二尖瓣脱垂（MVP）通常被认为是良性的，但最近提出的心律失常性 MVP（AMVP）形式仍未得到完全定义和确定。
本研究旨在确定 MVP 患者室性心律失常的患病率、严重程度、表型特征以及对预后的独立影响。
我们确定了一个连续的 595 例 MVP 患者队列（年龄 65 ± 16 岁；278 例女性），并对其进行了全面的临床、心律失常（24 小时动态心电图监测）和多普勒超声心动图特征分析。分析了长期预后。
室性心律失常很常见（43%至少有≥5%的室性早搏），最常见为中度（室性心动过速[VT]；120 至 179 次/分），占 27%，很少为重度（VT≥180 次/分），占 9%。室性心律失常的存在与男性、双叶脱垂、明显瓣叶冗余、二尖瓣瓣环分离（MAD）、左心房和左心室收缩末期直径较大以及 T 波倒置/ST 段压低有关（均 p≤0.001）。严重室性心律失常与 MAD、瓣叶冗余和 T 波倒置/ST 段压低的存在独立相关（均 p<0.0001），但与二尖瓣反流严重程度或射血分数无关。心律失常诊断后 8 年的总死亡率（13 ± 2%）与心律失常严重程度密切相关（8 年；无/轻度心律失常为 10 ± 2%，轻度和/或中度心律失常为 15 ± 3%，重度心律失常为 24 ± 7%；p=0.02）。严重心律失常的死亡率显著升高（单变量风险比[HR]：2.70；95%置信区间[CI]：1.27 至 5.77；p=0.01 与无/轻度心律失常相比），即使在综合调整包括 MVP 特征后（调整后的 HR：2.94；95%CI：1.36 至 6.36；p=0.006），以及通过时间依赖性分析（调整后的 HR：3.25；95%CI：1.56 至 6.78；p=0.002）。严重心律失常也与更高的死亡率、除颤器植入和 VT 消融（调整后的 HR：4.68；95%CI：2.45 至 8.92；p<0.0001）的发生率相关，尤其是在药物治疗下（调整后的 HR：5.80；95%CI：2.75 至 12.23；p<0.0001），而在二尖瓣手术后则较弱（调整后的 HR：3.69；95%CI：0.93 至 14.74；p=0.06）。
在本 MVP 患者的大队列中，Holter 监测的室性心律失常很常见，但很少为重度。AMVP 与 MAD、明显瓣叶冗余和复极化异常为主的表型独立相关。长期严重心律失常与明显的超额死亡率和降低的无事件生存率独立相关，尤其是在药物治疗下。因此，AMVP 是一种与预后密切相关的临床实体，需要进行仔细的风险评估和精心设计的临床试验。
