闭环刺激起搏在血管迷走性晕厥治疗中的应用现状分析

起搏器治疗血管迷走性晕厥的获益目前仍存在争议,通常建议用于难治性迷走性晕厥伴发心脏停搏的患者。闭环刺激起搏通过感知程控发现心脏收缩性的变化从而增加心率对血压下降作出应答。目前多项随机观察研究结果表明闭环刺激起搏对于减少心脏抑制型血管迷走性晕厥患者的晕厥发作优于传统起搏治疗,少数研究结果表明闭环刺激起搏对于减少血管抑制型和混合型迷走性晕厥患者的晕厥发作治疗有限。     

血管迷走性晕厥患者的心率变异性分析

心率变异性(Heart rate variability,HRV)是指窦性心率在一定时间内周期性改变的现象,HRV分析是一种敏感性高、无创性的心脏自主神经功能的定量检测方法⑴。目前认为,自主神经系统在血管迷走性晕厥中起重要作用。血管迷走性晕厥患者神经调节功能异常是晕厥的始发因素⑵。本文旨在对血管迷走性晕厥的心率变异性进行分析,以评价心脏自主神经张力的改变及其意义。     

血管迷走性晕厥患者倾斜试验中血浆内皮素内皮舒张因子和心 …

通过研究血管迷走性晕厥患者倾中血皮泊性血管活性物质和心率变异性的变化来了解自主神经及血管内皮功能在血管迷走性晕厥发生机制中的作用。方法２５例患者，斜试验阳性１５例，阴性１０例，于倾斜试验前和倾斜不同时间测定血浆内皮素、一氧化氮水平，脂用动态心电图监测心率变异性的变化。     

闭环刺激起搏器治疗血管迷走性晕厥(附一例报告)

血管迷走性晕厥一般可以选用药物治疗,其中的心脏抑制型和混合型还可选用带有防止频率骤降功能的起搏器来治疗,但由于其价格昂贵,有一部分患者不能接受.也有入报道可使用普通双腔起搏器来治疗,但其效果并不肯定.我们采用Biotronik公司的INOS2+CLS闭环刺激频率应答起搏器治疗一例血管迷走性晕厥的患者,取得良好效果,现报告如下:     

青年血管迷走性晕厥患者的心率变异性分析

血管迷走性晕厥是诸多晕厥中既特殊又常见的一种类型 ,晕厥发作先有交感神经活性的激活 ,后有迷走神经的过度反应 ,倾斜试验有助于血管迷走性晕厥的确诊。心率变异性常用以评价心脏交感神经与迷走神经的功能。对青年血管迷走性晕厥患者非发作期的心率变异性研究介绍如下。1.资料与方法 :对照组 15例健康女性 ,年龄 19～ 30 (2 2 6± 6 2 )岁 ,基础倾斜试验和多阶段异丙基肾上腺素倾斜试验均阴性。患者组 12例女性患者 ,年龄2 0～ 30 (2 2 8± 6 6 )岁 ,无心脏病及其它疾病 ,基础倾斜试验均阳性 ,确诊为血管迷走性晕厥。采用美国ＰＩ公司…     

头面部恶性肿瘤致反复晕厥行起搏器治疗二例

病例1患者舌癌颈部转移,窦性停搏和反复晕厥,行起搏器植入后晕厥消失;病例2患者反复晕厥,住院期间发现长RR间歇及血压下降,考虑血管迷走性晕厥,行抗晕厥起搏器植入后晕厥未发,但仍有反复头晕,最终确诊为鼻咽癌,行放疗后症状消失。上述病例提示：临床医师应提高对肿瘤所致晕厥的认识。     

心率变异和体液因素在血管迷走性晕厥诊断中的应用

我们对90例血管迷走性晕厥患者的心率变异和倾斜试验时血浆去甲肾上腺素(NE)、肾素活性(RA)、血管紧张素(Ang)和醛固酮(ADS)等交感神经-体液活性因子进行分析,探讨直立倾斜试验中心率变异和体液因素在血管迷走性晕厥诊断中的应用价值.     

血管迷走性晕厥的机理及治疗进展

血管迷走性晕厥机制复杂。Bezold-Jarisch反射是最常见的激发机制。交感神经活性变化、5-羟色胺、肾素-血管紧张素系统和内皮功能异常等在发病中起重要作用。目前血管迷走性晕厥的治疗包括一般治疗、倾斜训练、药物治疗和起搏器治疗。     

硝酸甘油倾斜试验中交感神经活性变化的临床研究

血管迷走性晕厥过去是在排除其他类型晕厥的基础上诊断的，诊断步骤复杂、费时。舌下含化硝酸甘油倾斜试验是诊断血管迷走性晕厥的一项特殊性检查，操作简便，省时。通过对血压、心率及血浆肾上腺素和去甲肾上腺素浓度的测定，以研究舌下含化硝酸甘油倾斜试验中交感神经活性变化，从而对其诱发血管迷走性晕厥的机制进行探讨。     

倾斜试验诱发血管迷走性晕厥的反应及有关机制探讨

为探讨倾斜试验诱发血管迷走性晕厥的反应及有关机制，对１１０例不明原因晕厥患者及３７例正常人观察倾斜试验（ＴＴＴ）时血管迷走性反应。结果显示：ＴＴＴ阳性、阴性及正常对照组之间基础舒张压（ＤＢＰ），基础心率×ＤＢＰ差异均无显著性，而ＴＴＴ阳性病人晕厥即刻ＤＢＰ，ＤＢＰ×心率与基础状态各指标比较，差异则有显著性，但晕厥即刻心率和基础心率比较，差异无显著性，说明血管迷走性晕厥（ＶＳ）的反应以血压变化为主为先，心率变化较迟或不明显，提示ＢＰ和心率的变化并非同一机制所致。ＴＴＴ阳性病人中异丙肾上腺素激发者占７０％，反映了ＶＳ的发生可能与β－受体高敏感性有关。ＴＴＴ的应用为研究ＶＳ的发病机理提供了手段。     

血管迷走性晕厥

血管迷走性晕厥（VVS）是临床中的最常见晕厥原因,是指各种刺激通过迷走神经介导反射导致血管扩张及心率减慢,造成脑部低灌注缺氧而出现短暂的意识丧失。VVS发作前有情绪紧张、长时站立等诱因并伴有典型的前驱症状。VVS是一种预后相对良好的疾病,在健康宣教的基础上,一般不需要特殊治疗,发作频繁、症状重者可考虑药物、起搏器或神经消融治疗。     

血管迷走性晕厥三种反应类型的心率变异分析

目的对倾斜试验(HUT)中三种不同反应类型的血管迷走性晕厥(VVS)患者进行心率变异分析(HRV)，探讨其不同的发病机制。方法54例不明原因晕厥患者倾斜75度进行持续45min的基础倾斜试验(BHUT)或只到发生晕厥，阴性患者于BHUT结束时恢复到平卧位，含服硝酸甘油0．3mg，然后倾斜75度进行持续20min的硝酸甘油诱导的倾斜试验(NTHUT)或只到发生晕厥，试验过程中进行间隔3min的心率变异分析。结果VVS患者中，血管抑制型(VD)和心脏抑制型(CI)均为8例，阳性率为14．8l％；混合型(MX)10例，阳性率为18．52％。倾斜75度后三组VVS患者的LFn值均增大，HFn值均减小；晕厥前3min时三组VVS的LFn值均升至最高，HFn值降至最低；晕厥时三组VVS患者的LFn值与晕厥前3min相比明显下降，但与倾斜前相比无明显差异；CI和MX组的HFn值与晕厥前3min相比明显增高，与倾斜前相比变化不大，VD组的HFn值与晕厥前3min相比无明显差异；未晕厥组在HUT过程中交感神经活性逐渐增大，试验结束时达到最大，迷走神经活性逐渐减小，试验结束时达到最小。结论VVS的发生与自主神经功能障碍有关，不同类型的VVS患者具有不同的神经调节障碍。     

Dynamic changes in the QT interval during the head-up tilt test in patients with vasovagal syncope

Dynamic changes of the QT and QTc interval as well as QT dispersion and QTc dispersion during the head-up tilt test were investigated in 15 patients (8 men, mean age 32 years) with vasovagal syncope (VVS) and a positive head-up tilt test and in a control group of 15 patients with syncope in the case-history and a negative head-up tilt test (9 men, mean age 33 years). The value at rest of the QT interval did not differ in patients with VVS and controls. In controls at the beginning of HUT shortening of QT occurred (0.447 sec. vs. 0.419 sec. p = 0.0002), subsequently the QT did not change significantly. In patients with VVS during the beginning of the test only an insignificant shortening of QT occurred, while during the development of the syncope QT was prolonged (0.394 sec. vs. 0.420 sec. p < 0.0001). QT corrected for the pulse rate (QTc) did not change significantly during HUT. QTc dispersion was in patients with VVS significantly lower 3 minutes before the development of the syncope (0.067 sec. vs. 0.085 sec. p = 0.03), which may indicate the decline of the sympathetic and increase of the parasympathetic tonus which subsequently leads to the development of vasovagal syncope. QTc dispersion before the test was higher in patients with VVS as compared with controls (0.087 sec. vs. 0.063 sec., p = 0.03), which suggests an increase in the baseline sympathetic tonus in patients with VVS.     

An implantable loop recorder study of highly symptomatic vasovagal patients: the heart rhythm observed during a spontaneous syncope is identical to the recurrent syncope but not correlated with the head-up tilt test or adenosine triphosphate test.

OBJECTIVES: The aim of this study was to analyze the heart rhythm during spontaneous vasovagal syncope (VVS) in highly symptomatic patients with implantable loop recorders (ILR) and to correlate this rhythm with the heart rhythm observed during head-up tilt test (HUT). BACKGROUND: Heart rhythm obtained during provocative condition is often used to guide therapy in VVS. To date there is no conclusive evidence that the heart rhythm observed during a positive HUT can predict heart rhythm during VVS or that the heart rhythm observed during a spontaneous syncope will be identical to the recurrent syncope. METHODS: Twenty-five consecutive VVS patients (age 60.2 +/- 17.1 years; 14 women,) presenting with frequent syncopes (6.9 +/- 4.6 episodes/year) and a positive HUT (cardioinhibitory in 8 patients) were implanted with an ILR. Seven of them also had a positive adenosine triphosphate (ATP) test. RESULTS: Follow-up was 17.0 +/- 3.6 months. Thirty VVS were observed in 12 patients. Nine episodes showed bradycardia of <40 beats/min or asystole; progressive sinus bradycardia preceding sinus arrest was the most frequent electrocardiographic finding. Twenty-one syncopes occurred without severe bradycardia. The heart rhythm observed during the first syncope was identical to the recurrence. No correlation was found between slow heart rate at the ILR interrogation and a cardioinhibitory HUT response (p = 1.0) or a positive ATP test (p = 1.0). CONCLUSIONS: In highly symptomatic patients with VVS, the heart rhythm observed during spontaneous syncope does not correlate with the HUT. The heart rhythm during the first spontaneous syncope is identical to the recurrent syncope.     

血管迷走性晕厥单中心294例结果分析

目的:对单中心33个月所做的直立倾斜试验(HUTT)结果进行分析并探讨健康教育对HUTT阳性患者再发晕厥次数的影响.方法:收集从2015年2月至2017年11月因反复晕厥或反复出现晕厥前兆在南京医科大学第一附属医院就诊并进行HUTT患者294例.根据HUTT中患者心率与血压的变化,196例HUTT呈阳性,其中混合型血管...     

177例血管迷走性晕厥的临床特征及治疗转归

目的对血管迷走性晕厥(VVS)患者的临床特征及治疗转归进行总结。方法 177例患者经倾斜试验确诊为VVS,对其VVS的类型、年龄段分类、发作晕厥的症状和体征、不同季节发生情况以及治疗转归进行统计。结果血管抑制型56例、心脏抑制型6例、混合抑制型115例,分别占31.6%、3.4%、65.0%。所有患者在晕厥发生前均有心率突然增快,继之突然下降的过程,可表现为窦性心动过缓、心脏停搏等心率缓慢的症状。倾斜试验阳性与季节似乎无关。年龄在40～59岁之间的人群中VVS发生较高。β受体阻滞剂治疗VVS有效。结论 VVS可能是自主神经失调所致,β受体阻滞剂抗交感治疗有效。     

Is vasovagal syncope a disease?

Vavovagal syncope (VVS) is not generally associated with cardiovascular, neurological or other diseases, and, therefore, represents an isolated manifestation. Isolated VVS cannot be regarded as a disease for several reasons: spontaneous syncope occurs in about half of individuals during their lives, and the unidentified neural pathways involved in the vasovagal response are probably present in all healthy humans, with individual differences in susceptibility; VVS is induced during tilt testing in several subjects with no history of syncope; during haemorrhagic shock, the vasovagal reaction can be observed in subjects with no history of syncope; about 20% of astronauts, who are selected on the basis of their great resistance to orthostatic stress, experience syncope or presyncope on landing after a short-duration space flight; to date, no genetic basis of VVS has been demonstrated; subjects with VVS are generally normotensive and, importantly, have normal blood pressure regulation apart from the episodes of syncope; hormonal disorders or a generalized state of autonomic involvement, although frequently investigated, have never been clearly demonstrated. Isolated VVS should be distinguished from those forms that start in old age and which are often associated with cardiovascular or neurological disorders, and other dysautonomic disturbances such as carotid sinus hypersensitivity, post-prandial hypotension, and symptoms of autonomic dysfunction. In these subjects, VVS appears as an expression of a pathological process, i.e. a disease, mainly related to a generalized involvement of the autonomic nervous system, which is not yet well-defined from a nosological point of view.     

Clinical characteristics of patients with vasovagal reactions presenting as unexplained syncope.

OBJECTIVE: To describe the clinical characteristics of vasovagal syncope (VVS) in patients presenting to a tertiary referral centre with unexplained syncope, in whom the diagnosis of VVS was confirmed by tilt table testing (HUT) and in whom other causes of syncope excluded. DESIGN: Prospective study of 62 consecutive patients with more than two episodes of syncope in the past year. SETTING: A regional tertiary referral centre for patients with unexplained syncope. PATIENTS: Sixty-two patients, mean age 50 +/- 21 years, 39 female, were studied. Mean duration of symptoms was 5 years. Average frequency of attacks was one episode per week. INTERVENTIONS: Detailed semi-structured questionnaires were completed regarding presenting symptoms. RESULTS: In over one-third of patients, episodes occurred suddenly, with no prodromal features. In those with prodrome, 71% had autonomic symptoms, but 27% had palpitations or dyspnoea and 21% had chest pain. Eleven percent of patients denied known provocative features. In the remainder, the most common were prolonged standing (37%), hot weather (27%) and lack of food (23%). One-fifth had symptoms sitting and 5% whilst driving. Seventy-five percent of patients suffered after effects, the most common being severe fatigue. Over half sustained an injury during syncope, and 13% sustained a fracture. Unwitnessed episodes occurred in 25%. Pallor was reported in half the cases, sweating in 13% and myoclonus in 5%. CONCLUSIONS: Atypical presentations of VVS occur in many patients referred to a tertiary referral centre. Knowledge of the clinical characteristics of unexplained syncope for which VVS is the attributable diagnosis should assist in appropriate management of such patients.     

Syncope and Structural Heart Disease: Historical Criteria for Vasovagal Syncope and Ventricular Tachycardia

Syncope and Structural Heart Disease. Introduction: To develop evidence‐based criteria that distinguish syncope due to ventricular tachycardia (VT) from vasovagal syncope (VVS) in patients with structural heart disease (SHD). Methods and Results: One hundred and thirty‐four patients with syncope and SHD completed a 118‐item questionnaire and underwent noninvasive and invasive diagnostic assessments in a prospective cohort study. The contributions of symptoms to diagnoses were estimated with logistic regression and a point score was developed and then tested using receiver‐operator characteristic analysis. The effectiveness of the decision rule was evaluated with long‐term outcome. There were 21 patients with tilt‐positive VVS, 78 with clinically declared or inducible VT, and 35 with no identified cause of syncope. Six features were significant predictors. Factors that predicted VT included male sex and age at onset >35 years; factors predicting VVS included prolonged sitting or standing; developing presyncope preceded by stress; recurrent headaches; and experiencing fatigue, which lasts longer than 1 minute after syncope. The point score correctly classified 92% of patients, diagnosing VT with 99% sensitivity and 68% specificity. The negative predictive value is ≥96%. Fully 67% of patients with undiagnosed syncope were classified as having VT based upon their symptoms. The decision rule predicted 9‐year arrhythmia‐free survival (VVS 84%, VT 39%, hazard ratio 4.32) and 9‐year overall survival (VVS 66%, VT 37%, hazard ratio 2.87). Conclusions: The causes of syncope in patients with SHD, and their clinical outcomes, can be estimated accurately based on the clinical history. The history safely screens out the possibility of VT as a cause of syncope. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1358‐1364, December 2010)     

Efficacy of tilt training in patients with vasovagal syncope

BACKGROUND: Besides pharmacological therapy and pacemaker implantation, tilt training is a promising method of treatment in patients with vasovagal syncope (VVS). Tilt training is usually offered to patients with malignant or recurrent VVS which impairs their quality of life and carries a risk of injury. AIM: To assess the efficacy of tilt training in patients with VVS. METHODS: The study group consisted of 40 patients (29 females, 11 males, aged 36.6+/-14 years, range 18-57 years) who underwent tilt training using tilt table testing according to the Westminster protocol. The mean number of syncopal episodes prior to the initiation of tilt training was 6.5+/-4.9 (range 0-20); 3 patients had a history of very frequent faints. According to the VASIS classification, type I VVS (mixed) was diagnosed in 17 patients, type II (cardioinhibitory) in 22 subjects, and type III (vasodepressive) in one patient. Mean follow-up duration was 35.1+/-13.5 months. The control group, which did not undergo the tilt testing programme, consisted of 29 patients with VVS (25 females, 4 males, mean age 44.2+/-15.0 years) who had a mean of 3.3+/-3.2 (range 0-12) syncopal episodes in the past (p <0.05 vs study group); 6 of these patients had only pre-syncopal episodes. Type I VVS was diagnosed in 23 controls and type II VVS in 6 control subjects (syncope occurred during the passive phase of tilt testing in 7 subjects, whereas the remaining 22 fainted during NTG infusion). RESULTS: Of the patients from the study group, 3 underwent pacemaker implantation at the time of the initiation of tilt training. At the end of follow-up, 31 (77.5%) patients remained free from syncope recurrences, 5 had syncopal episodes during the initial phase of tilt training, whereas the remaining 4 continued to suffer from syncopal episodes. Out of 3 patients with presyncope, 2 had no syncope recurrences whereas 1 patient continued to have presyncopal attacks. Out of 3 patients with pacemakers, 1 reported activation of pacing in the interventional mode. During the follow-up period, in 5 patients from the study group the diagnosis of VVS was not confirmed and another condition was diagnosed. In the control group, syncope recurrences occurred in 13 (44.5%) patients (p <0.05 vs study group). CONCLUSIONS: In patients with VVS, tilt training is effective in the majority of patients. Syncopal or presyncopal episodes and positive results of tilt testing take place more frequently in the early rather than in the late phase of training. Cessation of tilt training causes a recurrence of positive results of tilt testing in spite of the lack of spontaneous syncopal episodes. During long-term observation, a proper diagnosis, different from VVS, can be established in some patients.