Department of Cardiology, Heart Lung Center, Leiden University Medical Centre, Albinusdreef 2, 2300RC Leiden, The Netherlands.
Eur Heart J Cardiovasc Imaging. 2020 Oct 20;21(11):1227-1234. doi: 10.1093/ehjci/jeaa187.
Left ventricular (LV) mechanical dispersion (MD) may result from heterogeneous electrical conduction and is associated with adverse events. The present study investigated (i) the association between LV MD and the extent of LV scar as assessed with contrast-enhanced cardiac magnetic resonance (CMR) and (ii) the prognostic implications of LV MD in patients after ST-segment elevation myocardial infarction.
LV MD was calculated by echocardiography and myocardial scar was analysed on CMR data retrospectively. Infarct core and border zone were defined as ≥50% and 35-50% of maximal signal intensity, respectively. Patients were followed for the occurrence of the combined endpoint (all-cause mortality and appropriate implantable cardioverter-defibrillator therapy). In total, 96 patients (87% male, 57 ± 10 years) were included. Median LV MD was 53.5 ms [interquartile range (IQR) 43.4-62.8]. On CMR, total scar burden was 11.4% (IQR 3.8-17.1%), infarct core tissue 6.2% (IQR 2.0-12.7%), and border zone was 3.5% (IQR 1.5-5.7%). Correlations were observed between LV MD and infarct core (r = 0.517, P < 0.001), total scar burden (r = 0.497, P < 0.001), and border zone (r = 0.298, P = 0.003). In total, 14 patients (15%) reached the combined endpoint. Patients with LV MD >53.5 ms showed higher event rates as compared to their counterparts. Finally, LV MD showed the highest area under the curve for the prediction of the combined endpoint.
LV MD is correlated with LV scar burden. In addition, patients with prolonged LV MD showed higher event rates. Finally, LV MD provided the highest predictive value for the combined endpoint when compared with other parameters.
左心室（LV）机械弥散（MD）可能是由于电传导的异质性引起的，并与不良事件相关。本研究旨在探讨（i）LV MD 与对比增强心脏磁共振（CMR）评估的 LV 瘢痕程度之间的关系，以及（ii）LV MD 在 ST 段抬高型心肌梗死患者中的预后意义。
通过超声心动图计算 LV MD，回顾性地在 CMR 数据上分析心肌瘢痕。梗死核心和边缘区分别定义为≥50%和 35-50%的最大信号强度。对患者进行随访，以观察复合终点（全因死亡率和适当的植入式心脏复律除颤器治疗）的发生情况。共纳入 96 例患者（87%为男性，57±10 岁）。LV MD 的中位数为 53.5ms[四分位距（IQR）为 43.4-62.8]。在 CMR 上，总瘢痕负荷为 11.4%（IQR 为 3.8-17.1%），梗死核心组织为 6.2%（IQR 为 2.0-12.7%），边缘区为 3.5%（IQR 为 1.5-5.7%）。LV MD 与梗死核心（r=0.517，P<0.001）、总瘢痕负荷（r=0.497，P<0.001）和边缘区（r=0.298，P=0.003）呈正相关。共有 14 例患者（15%）达到复合终点。与 LV MD≤53.5ms 的患者相比，LV MD>53.5ms 的患者的事件发生率更高。最后，LV MD 对复合终点的预测具有最高的曲线下面积。
LV MD 与 LV 瘢痕负荷相关。此外，LV MD 延长的患者事件发生率更高。最后，与其他参数相比，LV MD 对复合终点的预测具有最高的预测价值。
