Meel Ruchika, Peters Ferande, Khandheria Bijoy K, Libhaber Elena, Essop Mohammed
Division of Cardiology, Chris Hani Baragwanath Academic Hospital and University of the Witwatersrand, Johannesburg, South Africa.
Aurora Cardiovascular and Thoracic Services, Aurora Sinai/Aurora St. Luke's Medical Centers, University of Wisconsin School of Medicine and Public Health, Marcus Family Fund for Echocardiography (ECHO) Research and Education, Milwaukee, Wisconsin, USA.
Echo Res Pract. 2020 Apr 6;7(2):9-17. doi: 10.1530/ERP-19-0034. eCollection 2020 Jun.
Chronic mitral regurgitation (MR) historically has been shown to primarily affect left ventricular (LV) function. The impact of increased left atrial (LA) volume in MR on morbidity and mortality has been highlighted recently, yet the LA does not feature as prominently in the current guidelines as the LV. Thus, we aimed to study LA and LV function in chronic rheumatic MR using traditional volumetric parameters and strain imaging.
Seventy-seven patients with isolated moderate or severe chronic rheumatic MR and 40 controls underwent echocardiographic examination. LV and LA function were assessed with conventional echocardiography and 2D strain imaging.
LA stiffness index was greater in chronic rheumatic MR than controls (0.95 ± 1.89 vs 0.16 ± 0.13, = 0.009). LA dysfunction was noted in the reservoir, conduit, and contractile phases compared with controls ( < 0.05). LA peak reservoir strain (Ɛ), LA peak contractile strain, and LV peak systolic strain were decreased in chronic rheumatic MR compared with controls ( < 0.05). Eighty-six percent of patients had decreased LA Ɛ and 58% had depressed LV peak systolic strain. Decreased Ɛ and normal LV peak systolic strain were noted in 42%. Thirteen percent had normal Ɛ and LV peak systolic strain. One patient had normal Ɛ with decreased LV peak systolic strain.
In chronic rheumatic MR, there is LA dysfunction in the reservoir, conduit, and contractile phases. In this study, LA dysfunction with or without LV dysfunction was the predominant finding, and thus, LA dysfunction may be an earlier marker of decompensation in chronic rheumatic MR.
既往研究表明，慢性二尖瓣反流（MR）主要影响左心室（LV）功能。近期，MR患者左心房（LA）容积增加对发病率和死亡率的影响受到关注，但在当前指南中，LA的地位不如LV突出。因此，我们旨在利用传统容积参数和应变成像技术研究慢性风湿性MR患者的LA和LV功能。
77例孤立性中度或重度慢性风湿性MR患者和40例对照者接受了超声心动图检查。采用传统超声心动图和二维应变成像技术评估LV和LA功能。
慢性风湿性MR患者的LA僵硬度指数高于对照组（0.95±1.89 vs 0.16±0.13，P=0.009）。与对照组相比，慢性风湿性MR患者在心房储存期、管道期和收缩期均存在LA功能障碍（P<0.05）。与对照组相比，慢性风湿性MR患者的LA储存期峰值应变（Ɛ）、LA收缩期峰值应变和LV收缩期峰值应变均降低（P<0.05）。86%的患者LAƐ降低，58%的患者LV收缩期峰值应变降低。42%的患者Ɛ降低但LV收缩期峰值应变正常。13%的患者Ɛ和LV收缩期峰值应变均正常。1例患者Ɛ正常但LV收缩期峰值应变降低。
在慢性风湿性MR患者中，心房储存期、管道期和收缩期均存在LA功能障碍。在本研究中，LA功能障碍伴或不伴LV功能障碍是主要发现，因此，LA功能障碍可能是慢性风湿性MR失代偿的早期标志物。
