QT间期离散度与心肌梗塞预后的关系

目的探讨ＣＴ间期离散度对急性心肌梗塞近期预后的预测价值．方法计算方法：每导联均测ＱＴ间期３～５个．取均值．则ＱＴ间期离散度（ＱＴｄ）＝ＱＴｍａｘ－ＱＴｍｉｎ，用心率校正后的ＱＴ间期（ＱＴｃ）的离散度（ＱＴｃｄ）＝ＱＴｃｍａｘ－ＱＴｃｍｉｎ．结果急性心肌梗塞组与对照组ＱＴｃ、ＱＴｄ．ＱＴｃｄ值比较有显著差异（Ｐ＜０．００１）．梗塞组有无恶性心律失常及猝死者ＱＴｃ、ＱＴｄ、ＱＴｅｄ对比有显著差异（Ｐ＜０．０１）．当ＱＴＣ≥４４０ｍｓ，ＱＴｄ、ＱＴＣｄ≥６０ｍｓ时发生恶性心律失常及猝死的诊断正确指数ＱＴｃｄ与ＱＴＣ、ＱＴｄ比较有明显差异（Ｐ＜０．０５）．但ＱＴｄ与ＱＴＣ比较无明显差异（Ｐ＞０．０５）．结论ＱＴ离散度能更好反映心室复极过程，尤其是用心率校正后的ＱＴ离散度，对判断急性心肌梗塞近期预后具有重要指导价值．     

急性心肌梗死直接经皮冠状动脉介入治疗对QT离散度的影响及其临床意义

目的 探讨直接经皮冠状动脉介入治疗（PCI）对急性心肌梗死（AMI）QT离散度的影响及其临床意义。方法 回顾性分析2001年1月-2004年12月在我院接受直接PCI且成功开通梗死相关血管的AMI患者228例。病例分AMI发病6h内（150例）和6h以上（78例）两组。测算和比较两组术前和术后第1天心电图QT间期、QT离散度、心率校正QT间期和心率校正QT离散度，并比较两组住院期间主要不良心血管事件（MACE）发生率。结果 两组QT间期和心率校正QT间期术后与术前相比均无显著性差异；但术后QT离散度和心率校正QT离散度较术前显著减小（P〈0.01），且发病6h以内组显著小于发病6h以上组（P〈0.05）；两组住院期间MACE发生率分别为14.6％和27.7％（P〈0.05）。结论 成功的介入治疗能显著减小心肌梗死患者的QT离散度，改善患者近期预后；介入治疗施行得越早则减小QT离散度和改善近期预后的效果越好。     

QT离散度在急性肺栓塞中的临床意义

目的: 探讨急性肺栓塞患者的QT离散度变化及临床意义。方法: 收集2011年5月至2012年4月中南大学湘雅医院急性肺栓塞患者42例,根据入院时情况分为高危组(16例)和非高危组(26例),以年龄与性别匹配的同时期健康体检者30例为正常对照组。肺栓塞患者入院24 h内及治疗后分别行同步十二导联心电图检查,手工测量QT间期,并计算出QT离散度(QT dispersion,QTd)及心率校正的QT离散度(heart rate-corrected QT dispersion,QTcd)。短期随访患者住院期间生存情况,根据生存情况分为生存组(31例)及死亡组(11例)。结果: QTd及QTcd在高危组[(70.2±34.0),(88.1±43.3) ms]及非高危组[(49.3±21.8),(59.1±26.2) ms]均显著大于正常对照组[(33.2±12.4),(36.7±14.2) ms](P<0.05);高危组又显著大于非高危组(P<0.05)。前后两次心电图间隔为(5.6±2.5) d,治疗后生存组QTd及QTcd [(41.0±16.4),(47.4±18.0) ms]较入院时[(54.0±33.0),(67.2±40.5) ms]显著减小(P<0.05),但仍大于正常组(P<0.05),死亡组治疗前后QTd及QTcd差异无统计学意义(P>0.05)。多元logistic回归分析表明:入院时高危、存在右室功能障碍、治疗后QTcd仍大于正常范围是住院期间死亡的主要影响因素。结论: 急性肺栓塞患者QTd及QTcd增大;合并右室功能障碍、入院时危险度高及治疗后QTcd大于正常范围者住院期间短期预后不良。     

急性心肌梗死患者经皮冠状动脉介入治疗对QT离散度的影响

目的 探讨经皮冠状动脉介入治疗对急性心肌梗死QT离散度的影响及其临床意义。方法 回顾性分析资料较完整的急性心肌梗死紧急冠脉介入治疗患者138例,测算术前和术后第1天心电图QT间期、QT离散度、心率校正QT间期和心率校正QT离散度。病例分心肌梗死发病6 h内(72例)和6 h以上(66例)两组。结果 两组QT间期和心率校正QT间期术后与术前相比均无显著性差异,但术后QT离散度和心率校正QT离散度较术前显著减小(P<0.01),且发病6 h内组显著小于发病6 h以上组(P<0.05);两组住院期间死亡率分别为4.2%和7.6%(P=0.394)。结论 成功的介入治疗能显著减小心肌梗死患者的QT离散度,介入治疗施行越早则减小QT离散度的效果越好。     

Pharmacokinetics of intravenous arsenic trioxide in the treatment of acute promyelocytic leukemia

Ａｒｓｅｎｉｃｔｒｉｏｘｉｄｅ（Ａｓ２Ｏ３）ｉｓｃｏｎｓｉｄｅｒｅｄａｓａｐｏｉｓｏｎ．Ｉｎｔｈｅｅａｒｌｙ１９７０ｓ,ｉｔｗａｓｉｎｔｒｏｄｕｃｅｄｔｏｔｒｅａｔａｃｕｔｅｐｒｏｍｙｅｌｏｃｙｔｉｃｌｅｕｋｅｍｉａ（ＡＰＬ）ａｎｄｃｈｒｏｎｉｃｍ...     

三氧化二砷不同给药方法治疗急性粒细胞白血病的临床观察和随访

目的　评价三氧化二砷 (As2 O3 )的两种给药方法在治疗急性早幼粒细胞白血病 (APL)中的有效性及安全性。方法　观察并随访了分别应用As2 O3 两种给药方法治疗的APL 96例 ,试验组 4 8例 ,按 0 16mg/kg计算每例患者As2 O3 的日治疗总量 ,分 2次加 5 %的葡萄糖液 2 5 0ml稀释 ,缓慢静脉滴注 ,每分钟 8滴 ,2次给药间隔 2～ 3h ;对照组 4 8例 ,按常规给药 0 16mg/kg计算As2 O3日治疗总量 ,每日用药 1次 ,2h完成。分别测两组患者不同时间点的血砷浓度 ,并随访治疗后 6个月中的复发率和砷蓄积情况。结果　连续用药 2 8d ,试验组总有效率为 93 8% ,对照组为 83 3%。血砷促凋亡有效浓度在 0 2mg/L以上的持续时间分别为试验组 18 4h± 3 3h ,对照组 9 4h± 1 6h。患者达到完全缓解的时间分别为 2 6 4d± 2 0d和 35 7d± 4 8d。随访 6个月两组骨髓抑制和复发率均未发现有差异。结论　分次缓慢静脉给药不良反应轻 ,并可缩短APL的完全缓解的时间 ,提高缓解率。     

全反式维A酸联合三氧化二砷治疗急性早幼粒细胞性白血病的临床研究

目的 研究全反式维A酸联合三氧化二砷治疗急性早幼粒细胞性白血病可产生的协同作用. 方法 我们对我院2006～2008年共9例急性早幼粒细胞性白血病采用两药联合化疗,予ATRA 10mg口服3-4次/天、As2O310mg静脉滴注3-4h每天1次,于第3天加用蒽环类抗肿瘤抗生素药物+阿糖胞苷化疗. 结果 联合治疗患者6例初发全部一疗程达到完全缓解(cR),复发病例中2例CR,中位时间30.12±4.89天. 结论 联合应用ATRA+As2O3和蒽环类抗肿瘤抗生素药物的化疗取代以往的单药治疗,取得较好的疗效,达到完全缓解的时间缩短,血小板计数恢复快,无病生存期延长.     

老年冠状动脉粥样硬化性心脏病患者心功能与肺动脉压和心电指标的关系

目的探讨老年冠状动脉粥样硬化性心脏病(CHD)患者心功能与肺动脉压(PAP)和心电指标的关系。方法 187例老年CHD患者按照纽约心脏病协会心功能分级分为Ⅰ级组42例、Ⅱ级组38例、Ⅲ级组59例和Ⅳ级组48例,测定4组患者的心电指标和PAP,并分析与患者心功能的关系。结果 4组患者P波离散度(Pd)、QT间期(QT)、QT离散度(QTd)、校正后的QT(QTc)、校正后的QTd(QTcd)、PAP、T波峰-末间期(Tp-e)和校正后的Tp-e(Tp-e/(RR)~1/2)比较差异均有统计学意义(P<0.05),且随着心功能的恶化,左心室射血分数逐渐降低,Pd、QT、QTc、QTd、QTcd、PAP、Tp-e和槡Tp-e/(RR)~1/2逐渐增加(P<0.05)。结论老年CHD患者随着心功能的恶化,PAP、Pd、QT、QTc、QTd、QTcd、Tp-e及槡Tp-e/(RR)~1/2有增加趋势。     

经皮冠状动脉腔内成形术对冠心病患者QT离散度的影响

目的通过分析经皮冠状动脉腔内成形术(percutaneoustransluminalcoronaryangioplasty,PTCA)中缺血和再灌注时QT离散度的变化。评价成功的PTCA术对改善QT离散度的临床意义。方法22例冠心病患者行成功的PTCA术治疗,其中男17例,女5例,年龄43～79岁,平均年龄(59.8±9.0)岁,记录PTCA术中及当日同步十二导联动态心电图。分别于术前、首次球囊扩张期间、首次球囊扩张后即刻、术后2h及12h测定QT间期和RR间期,QTd=QTmax-QTmin。结果QTd在首次球囊扩张期间与扩张前比较明显增大(P<0.05),在术后2h及12h均较术前减小(P<0.05),且术后12h与术后2h比较差异有统计学意义(P<0.05);首次球囊扩张后即刻与扩张前比较差异无统计学意义(P>0.05)。结论PTCA球囊扩张期间,由于产生一过性短暂的心肌缺血使QTd增加,而成功的PTCA术可降低冠心病患者的QT离散度,从而可能预防恶性室性心律失常的发生。     

急性心肌梗死溶栓治疗对QT离散度的影响及其意义

目的：探讨溶栓治疗对急性心肌梗死QT离散度的影响和意义。方法：41例急性心肌梗死患经溶栓治疗后分为溶栓再通组和溶栓未通组,分析溶栓前及溶栓后12－24h,2-4d和5－7d的ECG,测算QT,QTd,QTc和QTcd。结果：溶栓治疗前、后,再通组和未通组之间QT和QTc差异均无显性;溶栓再通组,溶栓治疗12h以后QTd和QTcd均较溶栓前明显减小;溶栓未通组,溶栓后5－7dQTd和QTcd才明显减小;溶栓后的1wk时间内,再通组QTd和QTcd均未通组明显减小。结论：成功的溶栓能减小急性心肌梗死的QTd,缩短QTd减小所需的时间。溶栓后QTd减小可能反映了顿抑或晕厥心肌的“苏醒”。     

急性心肌梗死患者急性期体表心电图T波峰末间期与恶性室性心律失常的关系研究

目的探讨急性心肌梗死患者体表心电图T波峰末间期(TpTe)与急性期室性心律失常的关系。方法102例接受直接PCI(pPCI)治疗的急性心肌梗死患者中,共有46例出现室性心动过速(VT)和心室纤颤(VF),作为病例组。其余56例未出现室性心律失常,作为对照组。测量并比较两组pPCI前后12导联心电图的QT、TpTe、QT离散度(QTd)及经心率校正的QT间期(QTc间期)、TpTe(TpTec)。研究室性心律失常与QTc和TpTec各时段上限值的相关性并比较不同梗死部位的QT及TpTe值。结果 pPCI治疗前两组对象的QT间期、QTd间差异无统计学意义(P>0.05),但QTc和TpTec间差异有统计学意义(P<0.05)。经pPCI治疗后第3天,两组间QT和QTd间差异仍无统计学意义,而QTc、TpTe和TpTec间差异有统计学意义(P<0.05)。pPCI治疗后1周TpTe、QTc和TpTec间差异仍有统计学意义(P<0.05)。两组pPCI治疗前后的RR间期无差异(P>0.05)。QTc间期各时段上限值与VT+VF的发生率无相关性(r=0.376,P>0.05)。TpTe及TpTec间期各时段上限值与VT+VF的发生率呈正相关(r=0.677,P<0.05;r=0.698,P<0.05)。结论在急性期出现VT和VF的急性心肌梗死患者与不出现室性心律失常的患者相比,TpTe和TpTec明显延长,但QT和QTd则无明显差异。TpTe可能预示着心肌梗死急性期恶性心律失常。     

急性心肌梗死QT离散度动态变化及其临床意义研究

目的观察急性心肌梗死患者经再灌注治疗后QTd的动态变化,探讨QTd动态变化的临床意义。方法对78例急性心肌梗死并及时给与再灌注治疗的患者,测定其发病后12小时内、13-72小时内、4-7天、8-15天的QT离散度。与对照组进行比较,观察急性心肌梗死后QTd的动态变化规律。结果急性心肌梗死组与对照组QTd值分别为:12小时内54.48±10.89ms、42.93±7.65ms;13-72小时内60.27±15.14ms、43.01±7.94ms;4-7天48.65±12.21ms、43.47±7.87ms;8-15天46.41±13.11ms、43.01±8.16ms。结论急性心肌梗死组QTd值均较对照组有不同程度的增高,心梗后13-72小时QTd值最高。     

Verapamil modulating arsenic trioxide-induced QT interval rolongation in guinea pig

Objective To investigate therapeutic action of verapamil on QT prolongation induced by arsenic trioxide (As2O3) in guinea pig and to further explore its possible mechanism. Methods Different doses of As2 O3 was infused intravenously to observe the changes of QT interval on the electrocardiogram (ECG) at different times in guinea pig. Patchclamp technique and laser scanning confocal microscopy were utilized to study the action of As2 O3 on action potential duration (APD),L-type calcium current (ICa-L ), rapid delayed rectifier potassium current (IKr) and intracellular calcium concentration ([Ca2+]i) of guinea pig myocytes. At the same time, verapamil was applied preliminarily to evaluate effects of verapamil on changes of the above index induced by As2O3. Results Intravenous administration of As2 O3 at the dose of 1.6mg/kg and 0.8mg/kg prolonged QT interval on ECG obviously in guinea pig hearts dose dependently and time dependently. QTc (corrected QT interval) was progressively prolonged in the 2-hour period of intravenous infusion of 1.6mg/kg As2O3 from (328.5 ± 30.9)ms of control to (388.4 ± 31.3)ms at 2h following As2O3 ( P ＜ 0.01) .When verapamil was pretreated for 5min, then 1.6mg/kg As2 O3 was added, the results showed that QTe was shorter in verapamil-treatment group (357.3±21.4)ms than that in As2O3 group (388.4±31.3)ms (P＜0.05) at 2h. Confocal experiments showed that in normal Tyrode solution, As2 O3 (1μmol/L and 10μmol/L) had no obvious effects on resting [Ca2+]i (P＞0.05) in guinea pig cardiomyocytes, however, 10μmol/L As2 O3 could markedly enhance [Ca2+]i increase induced by KCl 60mmol/L and the peak value increased from 903.4±369.4 to 1674.6±563.2 ( P＜0.05). The action of elevating [Ca2+]icould be blocked by 10μmol/L verapamil incompletely. The patch-clamp studies indicated that As2 O3 at concentration of 10μmol/L prolonged APD50 from (263.6 -±75.2)ms to (523.9±47.8)ms (P＜0.01) and APD90 from (277.5 ± 77.5)ms to (536.3 ±49.6)ms (P ＜0.01) ,and increased ICa-L from (- 6.0±1.5)pA/pF to (-8.7±2.0)pA/pF (P＜0.01) at 0mV and also reduced IKr from (6.7±1.8)pA/pF to (4.5±1.8)pA/pF (P＜0.05). However, 10μmol/L verapamil could modulate prolonging APD50 from (523.9 ± 47.8) ms to (340.4±83.8) ms ( P＜0.01) and APD90 from (536.3 ±49.6)ms to (348.9 ± 85.5)ms (P＜0.01) and correct increasing Ica-L induced by 10μmol/L As2O3 from (-8.7±2.0)pA/pF to ( - 6.6±1.4)pA/pF (P＜0.05) at 0mV. Conclusion As2O3 could induce prolongation of the QT interval on the ECG in guinea pig hearts and the ionic mechanism is associated with increasing Ica-L and inhibiting IKr/HERG. Verapamil may be useful in normalizing QT prolongation during As2 O3 therapy by decreasing Ica-L and [Ca2+]iof ventricular myocytes in guinea pig.     

EFFECTS OF ARSENIC TRIOXIDE ADMINISTRATION STYLES ON LEUKOCYTOSIS

ARSENIC trioxide ( As2O3) is effective in thetreatment of acute promyelocytic leukemia(APL) and many other kinds of malignant he-matopathies and solid carcinomas·1-5However, leukocytosisis commonly noticed with As2O3use, which severelythreatens the survi…     

Ventricular arrhythmias: Q-T prolongation and left ventricular hypertrophy in adult Nigerians with hypertensive heart disease

Seventy adult Nigerians with hypertensive heart disease (HHD) and 68 healthy controls were studied for ventricular arrhythmias (VA). The roles of QT prolongation and left ventricular hypertrophy in these arrhythmias were received. The mean age of the study population was 49.9 +/- 6.0 years. 14 (20.0%) patients had cardiac arrhythmias with 3 patients having premature ventricular contractions (PVC). Ten (14.3%) cases had QTc prolongation out of which 1 patient had PVC. Some factors that were found to be associated with QT prolongation in HHD include: left ventricular hypertrophy, persistently elevated systolic blood pressure and female gender. There was a positive correlation between left ventricular hypertrophy and QTc prolongation and also between QTc prolongation and frequency of ventricular arrhythmias.     

Verapamil modulating arsenic trioxide-induced QT interval prolongation in guinea pig

Objective To investigate therapeutic action of verapamil on QT prolongation induced by arsenic trioxide （As2O3） in guinea pig and to further explore its possible mechanism. Methods Different doses of As2O3 was infused intravenously to observe the changes of QT interval on the electrocardiogram （ECG） at different times in guinea pig. Patchclamp technique and laser scanning confocal microscopy were utilized to study the action of As2O3 on action potential duration （APD）,     

序贯疗法治疗急性早幼粒细胞白血病的临床观察

目的:探讨序贯疗法治疗急性早幼粒细胞白血病(APL)的长期疗效.方法:对39例初诊和3例复诊病人给予三氧化二砷(As2O3)诱导治疗,完全缓解(CR)后给予联合化疗和维甲酸交替治疗.结果:39例初诊病人中完成诱导分化治疗35例,均获得CR,有效率90%.3例复诊者经As2O3治疗后获CR,总有效率91%.4例复发者经As2O3治疗再获CR.总CR率达91%.经序贯疗法治疗后,全部病例均无病生存.结论:As2O3诱导治疗APL缓解率高,序贯疗法治疗APL患者CR期长,副作用轻.     

高血压病人QT离散度及其临床观察

目的:为探讨QT离散度(QTd)在正常人及高血压病患者的意义。方法:观察120例正常人和81例高血压病人的QTd及相关指标并进行了对比研究。结果:正常人的QTd(39.94±12.13毫秒)小于高血压病组(44.05±16.66毫秒),结论:QTd是一项准确、无创评价心室复极状态的指标。高血压病病人的QTd的增大与心室负荷过重有关。     

Cardiac autonomic dysfunction in sickle cell anaemia and its correlation with QT parameters

Background:

Abnormalities of QT parameters together with cardiac autonomic neuropathy (CAN) confer significant risks of cardiac morbidity and mortality in patients with diabetes mellitus. We questioned whether or not CAN influences occurrence of QT interval prolongation and dispersion in patients with sickle cell anaemia (SCA).

Materials and Methods:

Forty stable adult sickle cell patients with 44 healthy haemoglobin AA controls were studied. Baseline electrocardiograms were obtained and cardiovascular autonomic function tests were performed using standard protocols.

Results:

Mean corrected QT (QTc) in sickle cell patients was significantly higher (P = 0.001) than the mean of controls. Similarly, mean QT dispersion (QTcd) was higher (P = 0.001) in the former than in the latter. Mean QTc in patients with CAN was longer than patients with normal autonomic function (461 ± 26 ms versus 411 ± 23 ms), P = 0.001 (OR of 17.1, CI 3.48–83.71). Similarly, QTcd was higher (P = 0.001) in patients with CAN than those with normal cardiac autonomic function. Positive correlations were found between CAN with QTc and QTcd (r = 0.604, P = 0.001, r = 0.523, P = 0.001, respectively).

Conclusion:

CAN is a risk factor for abnormalities of QT parameters in SCA and both may be harbinger for cardiac death.     

2型糖尿病患者心率变异与QT离散度的关系

目的:探讨2型糖尿病(T2DM)的心率变异(HRV)与QT离散度(QTd)的关系。方法:选择2004年2月~2006年2月我院住院的糖尿病患者62例和正常人56例分别做24h动态心电图,经电脑系统分析得出HRV时域和频域分析参数,做12导联心电图,测定QT间期及QTd。结果:2型糖尿病组的HRV各项参数均低于正常人组,QTd均大于正常人组(P<0.05)。2型糖尿病组的QTd与SDNN、SDANN、SDNN-index均存在着负相关(P<0.05)。结论:2型糖尿病患者的心脏自主神经损坏较重,对2型糖尿病患者常规做24h动态心电图,测量QTd有助于早期发现高危患者。