Stroke Prevention,Evaluation of Bleeding Risk,and Anticoagulant Treatment Management in Atrial Fibrillation Contemporary International Guidelines

In recent years the management of atrial fibrillation patients has progressively and substantially changed because of the introduction of new treatments and the availability of new data regarding the epidemiology and clinical management of these patients. In the past 2 years alone, there have been 7 new guidelines or guideline updates that have been published, which have introduced new recommendations and significantly revised previously published ones. Two updates for Canadian guidelines were published in 2016 and 2018, whereas guidelines from the European Society of Cardiology in 2016, Asia Pacific Heart Rhythm Society were published in 2017, National Heart Foundation of Australia/Cardiac Society of Australia and New Zealand, American College of Chest Physicians, and Korean Heart Rhythm Society have been published in 2018. In this narrative review we provide a comparison of these contemporary international guidelines, with particular attention on the evaluation of thromboembolic and bleeding risks and management of oral anticoagulant therapy. From the analysis of contemporary guidelines on the management of atrial fibrillation, a general agreement is evident about the baseline evaluation of thromboembolic and bleeding risk, as well as a preference for the use of non-vitamin K antagonist oral anticoagulants. Also, regarding the concomitant use of oral anticoagulant and antiplatelet drugs in patients with acute coronary syndromes, undergoing elective percutaneous coronary intervention, catheter ablation, and cardioversion procedures, all of the guidelines agree on the general principles and are supported by evidence. More data are still needed to better substantiate recommendations for specific atrial fibrillation subpopulations. The need for an integrated approach and holistic management is highlighted in the more recently published guidelines.     

Comparison of primary coronary artery bypass surgery in a British Indo-Asian and white Caucasian population.

AIM: To compare the clinical characteristics, at the time of admission and after coronary revascularization by bypass surgery, among British patients of Indo-Asian and white Caucasian descent. METHOD: One hundred and ninety-four pairs of patients admitted between November 1994 and January 1997 were matched for age (within 3 years), sex and date of admission (within 3 months). Their clinical characteristics at the time of admission for coronary artery bypass grafting surgery, and the incidence of hospital morbidity, hospital mortality and length of stay in the intensive therapy unit or hospital following coronary artery bypass grafting were determined. RESULTS: A higher proportion of Indo-Asian patients underwent coronary revascularization on a non-elective basis (43% vs 32% white Caucasian patients, P =0.018), had a higher prevalence of diabetes (39% vs 12%, P =0.0001), a lower prevalence of smoking (36% vs 80%, P =0.0001) and a lower rate of previous myocardial infarction (47% vs 62%, P =0.012). As regards revascularization, although there was no significant difference in the number of vessels revascularized, there was a lower use of the arterial conduit (internal mammary artery) in the Indo-Asian patients (72% vs 81%, P =0.028) particularly for those undergoing emergency/urgent surgery (59% vs 72%, P =0.001) and with a previous myocardial infarction (65% vs 81%;P =0.01) when compared with their white Caucasian counterparts. Following surgery there were no differences in the types of support required for vital functions. There was no significant difference in the proportion of major post-operative complications, that is, haemorrhage, cerebrovascular accident, renal failure requiring dialysis or respiratory failure. Similarly, there were no differences in the length of intensive therapy unit stay (median stay 1 day vs 1 day, P =0.4) and hospital stay following surgery (median stay 6 days vs 6 days, P =0.5) between the two groups. Although there was a trend towards a higher in-hospital (30 day) mortality (6.7% [95% confidence intervals CI 3.18-10.21] vs 2.6% [CI 0.35-4.9;P =0.0618]), in Indo-Asians compared to white Caucasians this trend disappeared when patients in the two groups undergoing non-elective surgery only were compared (9% vs 7%;P =0.7). CONCLUSIONS: A higher proportion of Indo-Asians underwent non-elective coronary revascularization, with a significantly lower use of the arterial conduit and a relatively higher in-hospital mortality. Following coronary revascularization the medical management, length of stay and hospital morbidity in Indo-Asian patients was no different from that of their white Caucasian counterparts. This is despite a perceived poorer outcome in Indo-Asians compared to white Caucasians.     

小鼠脑缺血后的能量代谢改变和药物的作用

应用部分结扎小鼠颈总动脉(包括迷走神经)及小鼠断头法引起脑缺血后,脑组织的ATP和磷酸肌酸明显降低,乳酸明显升高。部分结扎颈动脉出现四肢无力、转圈及昏睡等症状,其严重程度与脑能量代谢改变相平行。皮下注射尼莫地平、硝苯吡啶、尼卡地平和三七皂甙对脑缺血有一定保护作用。苯巴比妥钠能改善正常和脑缺血小鼠的脑能量代谢,人参皂甙Rb₁可降低正常小鼠脑乳酸含量。     

新缩瞳剂包公藤甲素人工合成研究

包公藤甲素是从包公藤(Erycibe obtusifolia Benth.)茎中提得的一个新莨菪烷生物碱,具有强烈的缩瞳作用,临床用于治疗青光眼。本文报道用合成的6β-乙酰氧基托品酮为原料,经卤代、水解、还原和N-去甲基化等反应合成包甲素(8)。经光谱测定证实8与天然包甲素的结构完全一致。合成品系外消旋体,其作用机理与天然品相同,而强度则减半。