减少不良右室起搏的临床研究

目的观察心室起搏管理(Managing Ventricular Pacing,MVP)功能减少心室起搏百分比的效果。方法选择因病态窦房结综合征或房室阻滞而植入具有MVP功能的美敦力Adapta系列起搏器的患者共50例,分别程控为DDD模式和MVP模式,3个月后交叉程控为MVP模式和DDD模式,再随访3个月。结果两组患者DDD模式期间心室起搏百分比分别为40.5%(1.3%～90.1%)和39.9%(1.0～91.6%),两组患者MVP模式期间心室起搏百分比分别为5.8%(0～40.2%)和6.4%(0～32.4%)。MVP模式期间的心室起搏百分比明显低于DDD模式期间(p<0.05)。结论 MVP起搏模式能够降低因病态窦房结综合征或房室阻滞行永久性双腔人工心脏起搏器治疗患者的心室起搏百分比。     

心室起搏管理功能降低病窦综合征患者高比例的右室起搏

目的评估具有心室起搏管理(MVP)功能的双腔起搏器对高比例右室起搏的病窦综合征(SSS)患者的疗效。方法 35例SSS患者,房室传导正常或合并间歇性房室传导阻滞(AVB),至少植入了两年双腔起搏器(DDD/R),并计划更换,入组前1个月以上的心室起搏比例超过40%。均植入具有MVP功能的双腔起搏器,随机程控MVP启动(MVP on组,n=17)或者关闭(MVP off组,n=18)。术前、术后6个月行血浆脑钠肽(BNP)测定;心脏超声测定左室收缩末期内径(LVESD),左室舒张末期内径(LVEDD),左室射血分数(LVEF);并于术后6个月程控起搏器了解右室起搏比例、心房高频事件。结果术前两组血浆BNP及LVESD、LVEDD、LVEF比较无显著差异(P>0.05);术后两组有关心脏超声指标无明显变化(P>0.05)。MVP on组术后较术前血浆BNP有明显下降(P﹤0.05),与MVP off组比较,MVP on组术后右室起搏百分比、心房高频事件发生率均有显著下降(2.6%±0.6%vs 48.4%±10.5%,15.7%±2.3%vs 62.0%±7.8%;P﹤0.01)。结论具有MVP功能的DDD/R起搏器能降低高比例右室起搏的SSS的右室起搏比例及心房高频事件的发生率。     

一例心室起搏管理患者的心电图分析

1例因房室传导阻滞(AVB)植入具有心室起搏管理(MVP)功能起搏器患者的心电图,当房室传导功能正常时,以AAIR模式工作。出现间歇或短暂AVB,提供心室备用起搏。出现持续性AVB,转换为DDDR模式工作。具有MVP功能的起搏器可降低累计心室起搏百分比。     

对心室起搏管理的再认识

心室起搏管理(MVP)这一功能为美敦力公司开发,MVP模式下,双腔起搏器的基本起搏模式为AAI(R),但起搏器的心室通道具有感知功能和备用起搏功能,起搏模式可以在AAI(R)和DDD(R)之间转换。在AAI(R)起搏模式下,单个心房激动未下传激动心室并不触发起搏器发生模式转换,也不触发起搏器发放心室脉冲(VP),心室备用脉冲的发放时间为心房逸搏间期计时结束后的80 ms处;如果连续4个P波中有2个不能下传激动心室,则AAI(R)起搏模式将自动转换为DDD(R)起搏模式。MVP功能进行自身房室传导搜索时的心室漏搏会增加患者的不适,心室漏搏造成的长短周期序列可能会诱发心律失常,即使起搏器能搜索到自身房室传导,但如果自身房室传导间期过长,则失去了房室顺序收缩对心输出量的改善。如存在心房起搏功能或心房感知功能不良会造成房室不同步。病窦综合征患者植入有MVP功能的起搏器后,AAI(R)起搏模式下如果心房通道发生超感知,会导致心室漏搏。MVP功能打开时会抑制心室安全起搏功能发挥作用。如室性早搏或交界区早搏的QRS波位于心房起搏后80 ms内,不会被起搏器感知,使起搏器判断错误,起搏器误认为心室发生了漏搏,触发心室备用脉冲在心房逸搏间期结束后80 ms处发放。上述缺点限制了MVP功能在临床上的使用,如能对MVP功能做一改进,进行自身房室传导搜索时如果在两个心房事件间期的50%处或心房事件后一定时间处(如350 ms时)仍未搜索到自身房室传导时,起搏器发放心室备用脉冲,可能会减少MVP的不良影响,这一改进和AV Search的区别在于房室搜索是逐渐延长还是突然延长。     

心房起搏脉冲传导延迟患者AV问期的优化

目的探讨心房起搏至心房除极波时间延迟患者设置起搏的房室间期（PAV）的方法及远期心房起搏的有效性。方法分析2005年1月至2012年12月我院起搏器植入后发生心房起搏至心房除极波时间延迟≥lOOms的患者10例,病窦综合征（SSS）患者的房室间期设置为最大值,并最大限度开启房室问期滞后功能;对房室传导阻滞（AVB）患者设置PAV的值为：140～180ms＋心房起搏至心房除极波延迟时间,不开启AV滞后。结果经1个月至7年随访,5例SSS患者心室起搏比例〈10％,3例SSS患者心室起搏比例30％。50％,Holter显示心室起搏时为假性融合波,l例SSS患者及1例AVB患者为心室起搏心律,起搏比例〉99％,保证了房室问期的生理性。10例患者心房起搏阈值均〈1．5／0．4ms,未发生心房起搏阈值增高及失夺获。结论心房起搏至心房除极波时间延迟患者远期的心房起搏夺获是安全的;设置起搏器PAV间期要将心房起搏至心房除极波延迟时间计算其中,程控随访中应注意观察程控仪中监护图的心房波,房室传导阻滞患者可延长房室间期后观察心房波,部分患者因监护导联显示不清,需要通过12导联心电图进行观察,避免心房起搏至心房除极波延迟病例被遗漏．导致增加心室起搏及非生理性的房室间期。     

一种新的双腔起搏模式——AAISafeR与DDD模式的对比临床研究

目的评价存在自身房室传导置入双腔起搏器的患者,分别以DDD模式和AAISafeR模式工作3个月后心室起搏百分比以及临床指标。方法因病窦综合征置入Ela Symphony D 2450 DR2550系列双腔起搏器的患者30例,随机分为两组DDD组和AAISafeR组,3个月后交叉程控为AAISafeR和DDD,再随访3个月。结果没有观察到与AAISafeR有关的不良反应;AAISafeR模式能显著降低心室起搏的百分比51.3%(2%～91%)与0.9%(0～3%),(P=0.001);2.94%(0～18%)与41.18%(0～65%),(P=0.000);DDD模式工作3个月,左房直径、左室舒张末径、左室收缩末径均比术前增加,左室射血分数降低,差异有显著性,AAI SafeR模式工作3个月,除左房内径明显增大外,其余指标无明显改变;30例患者,在6个月的随访中,21例因不同程度的房室传导阻滞,AAI模式暂时转换为DDD模式。结论AAISafeR起搏模式能够有效降低心室起搏的百分比;AAISafeR起搏模式能够在出现房室传导阻滞的情况下,迅速安全的转换为DDD模式。     

起搏器更换时持续性心房颤动的发生情况分析

目的 探讨起搏器更换时持续性心房颤动(PAF)的发生情况.方法 124例行起搏器更换的患者根据病因分为病态窦房结综合征(SSS)组及房室阻滞(AVB)组,根据起搏模式分为DDD(R)及VVI(R)组,分析PAF的发生情况.结果 平均更换时间为(8.2±2.5)年,PAF发生率为26.6％(33/124).SSS组61例行VVI(R)起搏,22例行DDD(R)起搏.前者更换时PAF占34.4％(21/61),后者更换时PAF占18.2％(4/22).VVI(R)起搏PAF发生率高于DDD(R)起搏(34.4％对18.2％,P＜0.05).AVB组30例行VVI(R)起搏,11例行DDD(R)起搏.前者更换时PAF占23.3％ (7/30),后者更换时PAF占9.1％(1/11).VVI(R)起搏PAF发生率高于DDD(R)起搏(23.3％对9.1％,P＜0.05).结论 起搏器更换时PAF常见.无论是SSS或者AVB患者DDD(R)起搏PAF发生率低于VVI(R)起搏.     

不同起搏模式对减少心室起搏比例的临床观察

目的 观察患者置入具有工作模式转换功能的双腔起搏器对减少右心室起搏的临床疗效.方法 入选符合双腔起搏器置入指征的患者126例,采用随机、单盲、自身前后交叉对照研究方法,观察同一患者在心房按需型起搏模式(AAISafeR)和房室全能型起搏模式(DDD)2种工作模式下心室起搏百分比的比例,随访3个月.进行ECG和超声心动图的检查,分析心室起搏百分比与心房的相关性.结果 与DDD比较,AAISafeR模式下心室感知百分比明显增加(34.61±9.82)%vs(73.18±13.08)%,差异有统计学意义(P＜0.05),心室起搏百分比明显减少(83.71±11.76)%vs(23.61±7.05)%,差异有统计学意义(P＜0.05),AAISafeR模式减少右心室起搏60.1%.相关分析显示,左心室舒张末径与心室起搏百分比呈正相关(r=0.398,P=0.0003),LVEF与心室起搏百分比之问无显著相关关系(r=-0.13,P=0.26).结论 AAISafeR模式可有效减少心室起搏百分比,可能影响心腔结构短期内重构,但尚未引起心室功能的改变.     

起搏心电图上AV间期反复变化一例

患者女性,77岁,因Ⅲ度房室传导阻滞(AVB)植入VITA-TRON C60A3DDDR起搏器。术后随访心电图时发现AS-VP间期不断变化。通过程控仪发现心房单极及感知灵敏度设置太高,使心房电极发生交叉感知致双倍记数而发生逐跳自动起搏模式转换(AMS),出现DDD(AS-VP)与DDI(V-V)交替工作,最终引起AV间期的反复变化。由于交叉感知是间歇性出现的,导致了起搏器反复发生AMS,加之患者自身存在Ⅲ度AVB,产生了这样特殊的AV间期反复变化的起搏心电图现象。另外,Vitaron独有的心房同步起搏的算法也参与了术后起搏心电图多样化的形成。     

起搏器与电极导线不匹配一例

患者女性,61岁,因Ⅲ度房室传导阻滞植入DDD起搏器。心房、心室电极导线参数测试满意后与起搏器连接,心电监护示:心房率78次/分,心室率38次/分,未见心室起搏心律。术中探查,用程控仪测心室电极阻抗9999Ω,心房电极阻抗正常;然后将心房、心室电极导线互换分别插入起搏器心室、心房电极插入孔,测试示:心室电极导线阻抗9999Ω,心房电极导线阻抗正常。提示:心室电极导线与起搏器不匹配,更换心室电极导线,起搏器呈VDD起搏模式。     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.