超声心动图评估化疗药物对乳腺癌患者左心房结构、机械功能和机械离散度的影响

Value of Echocardiography in Evaluating the Left Atrial Function and Mechanical Dispersion in Breast Cancer Patients Undergoing Chemotherapy

目的:应用超声心动图评估化疗药物对乳腺癌患者左心房结构、机械功能和机械离散度(LAMD)的影响。方法:收集91例接受蒽环类和(或)曲妥珠单抗治疗的乳腺癌患者,根据化疗时间分为四组:化疗前24 h内组(T0组,n=91)、化疗后3个月组(T1组,n=81)、化疗后6个月组(T2组,n=76)、化疗后12个月组(T3组,n=35)。获取左心房最大容积指数、最小容积指数和收缩前容积指数,计算左心房的主动射血分数、被动射血分数和总射血分数。二维斑点追踪超声心动图测量左心房储备期、导管期和收缩期的应变、峰值应变率,LAMD定义为以心电图R-R间期校正的储备期应变达峰时间标准差。结果:化疗6个月后,LAMD明显增加[(4.3±1.2)%vs.(5.5±1.9)%,P<0.05],左心房储备期应变和峰值应变率[(30.2±5.4)%vs.(26.6±5.2)%,(1.3±0.2)/s vs.(1.1±0.2)/s]、左心房导管期应变和峰值应变率绝对值[(15.7±5.3)%vs.(12.4±4.1)%,(-1.3±0.5)/s vs.(-1.1±0.4)/s]均出现不同程度的降低(P均<0.05),而左心房收缩期应变、峰值应变率绝对值[(14.5±2.4)%vs.(12.9±2.9)%,(-1.8±0.3)/s vs.(-1.6±0.3)/s]在12个月后显著降低(P均<0.05),左心房容积指数及相关的功能参数则未见明显改变。相关性分析显示,相应时间点的左心房储备期应变和导管期应变均与LAMD呈负相关,而与二尖瓣环侧壁组织舒张早期多普勒速度(Em)呈正相关。结论:乳腺癌患者化疗后LAMD显著增加且持续存在,同时伴有左心房机械功能受损,提示患者未来新发心房颤动的风险增加。

Objectives:We aimed to evaluate the effect of chemotherapy drugs on the left atrium(LA)structure,function and mechanical dispersion(LAMD)in patients with breast cancer by echocardiography.Methods:91 breast cancer patients treated with anthracycline and/or trastuzumab were divided into 4 groups according to the time of chemotherapy:before chemotherapy(T0,n=91),3 months after chemotherapy(T1,n=81),6 months after chemotherapy(T2,n=76),and 12 months after chemotherapy(T3,n=35).To obtain the LA maximum volume index,LA minimum volume index and LA pre-contraction volume index,LA active ejection fraction,passive ejection fraction and total ejection fraction were calculated.LA strain and strain rate during reservoir phase,conduit phase,and contraction phase were obtained by two-dimensional speckle tracking echocardiography(2D-STE).LAMD was defined as the standard deviation of time to peak positive strain corrected by the R-R interval.Results:After 6 months therapy,the LAMD was significantly increased([4.3±1.2]%vs.[5.5±1.9]%,P<0.05),LA strain and strain rate absolute values during reservoir phase([30.2±5.4]%vs.[26.6±5.2]%,[1.3±0.2]/s vs.[1.1±0.2]/s)and conduit phase([15.7±5.3]%vs.[12.4±4.1]%,[-1.3±0.5]/s vs.[-1.1±0.4]/s)were significantly decreased(all P<0.05),LA strain and strain rate during contraction phase([14.5±2.4]%vs.[12.9±2.9]%,[-1.8±0.3]/s vs.[-1.6±0.3]/s)were significantly decreased after 12 months(all P<0.05),while no significant changes were noted in LA volume and function after chemotherapy as compared to baseline values.Correlation analysis showed that LA strain during reservoir phase and conduit phase was negatively correlated with LAMD,positively correlated with peak myocardial velocities in early diastole(Em).Conclusions:Long-term chemotherapy is associated with significant increased LAMD and impaired mechanical function of LA in this patient cohort.Future studies are warranted if such changes are related to increased risk of new onset of atrial fibrillation in these patients.