Department of Cardiology (O.A.E.S., M.J.C., M.M.), University Medical Center Utrecht, Utrecht University, the Netherlands.
Department of Cardiology, Maastricht University Medical Center, the Netherlands (A.M.W.v.S., K.V.).
Circ Arrhythm Electrophysiol. 2021 Jan;14(1):e008452. doi: 10.1161/CIRCEP.120.008452. Epub 2020 Dec 9.
Women are less likely to receive cardiac resynchronization therapy, yet, they are more responsive to the therapy and respond at shorter QRS duration. The present study hypothesized that a relatively larger left ventricular (LV) electrical dyssynchrony in smaller hearts contributes to the better cardiac resynchronization therapy response in women. For this, the vectorcardiography-derived QRS area is used, since it allows for a more detailed quantification of electrical dyssynchrony compared with conventional electrocardiographic markers.
Data from a multicenter registry of 725 cardiac resynchronization therapy patients (median follow-up, 4.2 years [interquartile range, 2.7-6.1]) were analyzed. Baseline electrical dyssynchrony was evaluated using the QRS area and the corrected QRS area for heart size using the LV end-diastolic volume (QRSarea/LVEDV). Impact of the QRSarea/LVEDV ratio on the association between sex and LV reverse remodeling (LV end-systolic volume change) and sex and the composite outcome of all-cause mortality, LV assist device implantation, or heart transplantation was assessed.
At baseline, women (n=228) displayed larger electrical dyssynchrony than men (QRS area, 132±55 versus 123±58 μVs; =0.043), which was even more pronounced for the QRSarea/LVEDV ratio (0.76±0.46 versus 0.57±0.34 μVs/mL; <0.001). After multivariable analyses, female sex was associated with LV end-systolic volume change (β=0.12; =0.003) and a lower occurrence of the composite outcome (hazard ratio, 0.59 [0.42-0.85]; =0.004). A part of the female advantage regarding reverse remodeling was attributed to the larger QRSarea/LVEDV ratio in women (25-fold change in β from 0.12 to 0.09). The larger QRSarea/LVEDV ratio did not contribute to the better survival observed in women. In both volumetric responders and nonresponders, female sex remained strongly associated with a lower risk of the composite outcome (adjusted hazard ratio, 0.59 [0.36-0.97]; =0.036; and 0.55 [0.33-0.90]; =0.018, respectively).
Greater electrical dyssynchrony in smaller hearts contributes, in part, to more reverse remodeling observed in women after cardiac resynchronization therapy, but this does not explain their better long-term outcomes.
女性接受心脏再同步治疗的可能性较低，但她们对治疗的反应更好，且 QRS 持续时间更短。本研究假设，较小心脏中相对较大的左心室（LV）电不同步导致女性对心脏再同步治疗的反应更好。为此，使用了心向量图衍生的 QRS 面积，因为与传统心电图标志物相比，它可以更详细地量化电不同步。
对来自 725 例心脏再同步治疗患者的多中心注册研究的数据（中位随访 4.2 年[四分位间距，2.7-6.1]）进行了分析。使用 QRS 面积评估基线电不同步，使用 LV 舒张末期容积（QRSarea/LVEDV）校正 QRS 面积心腔大小。评估 QRSarea/LVEDV 比值对性别与 LV 逆重构（LV 收缩末期容积变化）之间的关联以及性别与全因死亡率、LV 辅助装置植入或心脏移植的复合结局之间的关联的影响。
在基线时，女性（n=228）的电不同步程度大于男性（QRS 面积 132±55 比 123±58 μVs；=0.043），而 QRSarea/LVEDV 比值更为明显（0.76±0.46 比 0.57±0.34 μVs/mL；<0.001）。经过多变量分析，女性性别与 LV 收缩末期容积变化（β=0.12；=0.003）和复合结局的发生风险降低相关（危险比，0.59[0.42-0.85]；=0.004）。女性在逆重构方面的优势部分归因于女性 QRSarea/LVEDV 比值较大（β从 0.12 变为 0.09 的 25 倍变化）。较大的 QRSarea/LVEDV 比值与女性观察到的更好的生存率无关。在容量反应者和无反应者中，女性性别与复合结局风险降低仍然密切相关（校正危险比，0.59[0.36-0.97]；=0.036；和 0.55[0.33-0.90]；=0.018）。
较小心脏中更大的电不同步导致心脏再同步治疗后女性观察到的逆重构增加，但其不能解释女性更好的长期结局。
