背景:自发性回声对比(SEC)和左心耳血栓(LAAT)会增加房颤(AF)患者的卒中风险及其严重程度。形成更致密的纤维蛋白网络和受损的纤维蛋白溶解与房颤的卒中风险相关。这项研究调查了血栓前纤维蛋白凝块表型是否表征了SEC/LAAT患者。
方法:我们研究了139名房颤抗凝患者(中位年龄,70年),谁接受了经食管超声心动图(TEE)。记录SEC和LAAT。我们评估了血浆纤维蛋白凝块的特性,即渗透率(Ks)和凝块溶解时间(CLT),血管性血友病因子(vWF)抗原,内源性凝血酶电位(ETP),参与血栓形成和纤维蛋白溶解的蛋白质,以及血浆羰基化蛋白含量(PC)。
结果:在36名受试者(25.9%)中发现SEC/LAAT,并与心力衰竭(HF)相关。AF持续时间,更高的CHA2DS2VASc分数,脑钠肽N末端激素原,和生长分化因子15。SEC/LAAT患者的Ks较低(-15%)和CLT延长(19%),随着更高的纤维蛋白原(+24%),ETP(+3%),和纤溶酶原激活物抑制剂-1抗原(+16%)与其余的相比。凝血酶激活的纤溶抑制物抗原,纤溶酶原,α2-抗纤溶酶,和组织纤溶酶原激活物抗原在两组之间相似。SEC/LAAT中PC含量高50%,并与Ks(r=-0.47,p<0.001)和CLT(r=0.40,p<0.001)相关。在多变量分析中,Ks,CLT,和PC级别,随着HF,与SEC/LAAT保持独立关联。
结论:我们证实,尽管有抗凝治疗,但在患有SEC/LAAT的AF患者中,仍形成了更致密且溶解性差的纤维蛋白网络。我们认为这种现象部分与氧化应激增强有关。
BACKGROUND: Spontaneous echo contrast (SEC) and left atrial appendage thrombus (LAAT) increase the risk of stroke and its severity in patients with atrial fibrillation (AF). Formation of denser fibrin networks and impaired fibrinolysis are associated with stroke risk in AF. This study investigated whether the prothrombotic fibrin clot phenotype characterizes patients with SEC/LAAT.
METHODS: We studied 139 anticoagulated patients with AF (median age, 70 years), who underwent transesophageal echocardiography (TEE). SEC and LAAT were recorded. We assessed plasma fibrin clot properties, i.e. permeability (Ks) and clot lysis time (CLT), von Willebrand Factor (vWF) antigen, endogenous thrombin potential (ETP), proteins involved in thrombosis and fibrinolysis, as well as plasma carbonylated protein content (PC).
RESULTS: SEC/LAAT was identified in 36 subjects (25.9 %) and was associated with heart failure (HF), AF duration, higher CHA2DS2VASc score, N-terminal prohormone of brain natriuretic peptide, and growth differentiation factor 15. Patients with SEC/LAAT had lower Ks (-15 %) and prolonged CLT (+19 %), along with higher fibrinogen (+24 %), ETP (+3 %), and plasminogen activator inhibitor-1 antigen (+16 %) compared with the remainder. Thrombin-activatable fibrinolysis inhibitor antigen, plasminogen, α2 - antiplasmin, and tissue plasminogen activator antigen were similar between the two groups. PC content was 50 % higher in SEC/LAAT and correlated with Ks (r = -0.47, p < 0.001) and CLT (r = 0.40, p < 0.001). On multivariate analysis, Ks, CLT, and PC levels, along with HF, remained independently associated with SEC/LAAT.
CONCLUSIONS: We demonstrated a formation of denser and poorly lysable fibrin networks in AF patients with SEC/LAAT despite anticoagulation. We suggest that this phenomenon is in part related to enhanced oxidative stress.