背景:视网膜中央动脉阻塞(CRAO)是导致失明和视力发病的常见原因。在大多数情况下,与血栓栓塞有关.然而,遗传或获得性血栓性危险因素在CRAO发病机制中的作用尚未得到全面研究.
方法:在126例CRAO患者中(66例[52.4%]男性,中位年龄55[范围:18-80]岁)和107个匹配的对照(56[52.3%]男性,中位年龄53[范围:34-78]岁)我们评估了经典的动脉粥样硬化危险因素,包括血脂和血糖水平,分析颈外动脉的内膜-中膜复合体厚度(IMT),并进行了经胸超声心动图检查。此外,我们确定了遗传性和获得性血栓性危险因素的患病率,如因子V莱顿(FVL)和凝血酶原20210G/A遗传变异,因子(F)VIII的血浆活性,蛋白C和抗凝血酶活性,和游离蛋白S水平。我们还评估了抗磷脂抗体(APLA)的存在,并评估了所有入选受试者的血液同型半胱氨酸。此外,我们估计了两组中凝血因子XIII(FXIII-A)A亚基的Val34Leu多态性作为潜在的血栓形成保护因子的发生率.
结果:在传统的动脉粥样硬化风险成分中,肥胖/超重和高胆固醇血症在CRAO组中最常见,发生在103(81.7%)和85(67.5%)患者中,分别。CRAO患者IMT升高,超声心动图参数改变,表明心脏舒张功能障碍。在血栓形成倾向调查中,至少有一个实验室危险因素发生在72.2%(n=91)的CRAO患者中,APLA是最常见的,在38.1%(n=48)的患者中检测到(几乎是对照组的7倍,p<0.001)。蛋白C活性和游离蛋白S水平的缺乏在CRAO组中也很常见,在17.5%(n=22)和19.8%(n=25)的患者中报告,分别。有趣的是,在两个分析的血栓前遗传变异中,只有FVL和CRAO有关,等位基因频率比对照组高2.4倍(p=0.044)。最后,CRAO组以高同型半胱氨酸血症为特征,几乎是对照组的两倍(p=0.026)。抗凝血酶缺乏症,升高的FVIII,FXIII-AVal34Leu多态性与CRAO无关。
结论:我们的研究结果表明,血栓形成倾向在CRAO的发病机制中起着至关重要的作用。因此,在这些发作的一级和二级预防中,应考虑适当的实验室筛查,根据需要实施适当的治疗。
BACKGROUND: Central retinal artery occlusion (
CRAO) is a common cause of blindness and visual morbidity. In the majority of cases, it is related to thrombotic embolism. Nevertheless, the role of inherited or acquired thrombophilic risk factors in
CRAO pathogenesis has not been comprehensively studied.
METHODS: In 126
CRAO patients (66 [52.4%] men, median age 55 [range: 18-80] years) and 107 matched controls (56 [52.3%] men, median age 53 [range: 34-78] years) we evaluated classical atherosclerotic risk factors, including serum lipid profile and glucose level, analyzed intima-media complex thickness (IMT) of external carotid arteries, and performed transthoracic echocardiography. Furthermore, we established the prevalence of inherited and acquired thrombophilic risk factors, such as factor V Leiden (FVL) and prothrombin 20210 G/A genetic variants, plasma activity of factor (F) VIII, protein C and antithrombin activity, and free protein S levels. We also assessed the presence of antiphospholipid antibodies (APLA) and evaluated blood homocysteine in all enrolled subjects. Additionally, we estimated the occurrence of Val34Leu polymorphism of the A subunit of coagulation factor XIII (FXIII-A) in both groups as a potential thrombosis-protecting factor.
RESULTS: Among traditional atherosclerotic risk components, obesity/overweight and hypercholesterolemia were the most common in the CRAO group and occurred in 103 (81.7%) and 85 (67.5%) patients, respectively. CRAO patients also had elevated IMT and altered echocardiographic parameters, indicating diastolic cardiac dysfunction. In thrombophilia investigations, at least one laboratory risk factor occurred in 72.2% (n = 91) of
CRAO patients, with APLA as the most frequent, detected in 38.1% (n = 48) of them (almost seven times more frequent than in controls, p < 0.001). Deficiencies in protein C activity and free protein S levels were also common in the CRAO group, reported in 17.5% (n = 22) and 19.8% (n = 25) of patients, respectively. Interestingly, among two analyzed prothrombotic genetic variants, only the FVL was related to
CRAO, with the allelic frequency 2.4 times more prevalent than in controls (p = 0.044). Finally, the CRAO group was characterized by hyperhomocysteinemia, almost twice as common as in controls (p = 0.026). Antithrombin deficiency, elevated FVIII, and FXIII-A Val34Leu polymorphism were not associated with CRAO.
CONCLUSIONS: Our findings suggest that thrombophilia plays a vital role in the pathogenesis of CRAO. Thus, proper laboratory screening should be considered in the primary and secondary prevention of those episodes, with implementing appropriate therapy as needed.