心脏起搏器置入的术后护理

人工心脏起搏是通过人工心脏起搏器发放脉冲电流,通过导线和电极的传导刺激心肌,使之兴奋收缩,从而代替正常心脏起搏点,控制心脏按脉冲电流的频率有效地搏动,以治疗某些心律失常所致的心脏功能障碍,有永久性起搏和临时性起搏两种。因为临时起搏多用于严重心律失常的抢救,多数患者都有起搏依赖,而且,临时起搏电极容易脱位,所以术后监护更显十分重要。临床上对Ⅱ度Ⅱ型或Ⅲ度房室传导阻滞患者、病窦综合征患者植入心脏永久起搏器,取得了很好的治疗效果。起搏治疗的主要目的就是通过不同的起搏方式纠正心率和心律的异常,来提高患者的生存质量,减少病死率。     

心脏永久起搏器治疗对Ⅲ度房室传导阻滞伴发高血压患者的血压影响研究

目的：探讨心脏永久起搏器治疗对Ⅲ度房室传导阻滞伴发高血压患者的血压影响。方法：回顾性分析37例Ⅲ度房室传导阻滞伴发高血压患者起搏器植入术前后血压变化及起搏部位对血压的影响。结果：起搏器植入前后血压差异有统计学意义（P〈0.05）,起搏器植入右室流出道、右室心尖部前后的血压差值差异无统计学意义（P〉0.05）。结论：起搏器治疗能有效降低Ⅲ度房室传导阻滞伴发高血压患者的血压,起搏部位对血压无明显影响。     

50例心脏永久性起搏器植入患者的临床分析

目的观察50例不同模式起搏器植入的疗效及并发症。方法对50例不同模式的永久性起搏器植入患者进行随访观察,对术中疗效及术后各种并发症进行分析。结果不同模式的心脏永久性起搏治疗均能显著改善患者症状。（总有效率为98%）。生理性起搏（DDD及AAI模式）的治疗效果优于非生理性起搏（VⅥ模式）,分别增加左室射血分数50.2%,7.3%（P〈0.01）;手术并发症二者差异无统计学意义,但非手术并发症VⅥ（20%）明显多于DDD及AAI模式（3%）。结论心脏永久性起搏能有效改善心律失常患者的功能,DDD及AAI模式优于VⅥ模式。     

心脏瓣膜置换术同期双极射频消融治疗永久性心房颤动

目的探讨心内直视下同期行改良冲洗式双极射频消融治疗心瓣膜病合并永久性心房颤动的临床效果。方法回顾性分析2010年4月至2013年4月心脏瓣膜病合并永久心房颤动52例患者在体外循环下行心瓣膜置换术加改良冲洗式双极射频消融手术的临床资料。其中风湿性心脏瓣膜病47例,心瓣膜退行性病变5例;均合并永久性心房颤动,术中采用Medtronic Cardioblate 68000冲洗式双极射频消融系统进行消融操作。消融手术包括双侧肺静脉的环形隔离、左心耳切除、左右心房消融（改良Cox—maze Ⅲ手术路径）和Marshall韧带切除;术后常规予胺碘酮治疗。结果52例手术均顺利完成,平均消融时间为（14±6）min,全组无心脏穿孔,无手术死亡。术后当天有42例恢复为窦性心律。全组术后均予以口服盐酸胺碘酮维持6个月,有5例分别于术后1～7d发生阵发性心房颤动,经静脉注射盐酸胺碘酮后转为窦性心律。2例出现Ⅲ度房室传导阻滞,安装永久起搏器治疗,患者平均住院时间为（12．1±2．3）d。术后平均随访（8±4）个月,84．6％（44／52）维持窦性心律,11．5％（6／52）为房颤心律,3．8％（2／52）为起搏心律。结论心内直视下同期改良冲洗式双极射频消融治疗心脏瓣膜病合并永久性心房颤动是一种简易、安全、有效的方法。     

TAVI的前世、 今生和未来

摘要： 近年来, 钙化性主动脉瓣狭窄 （CAS） 发病率呈现逐年上升趋势, 患者出现心绞痛、 呼吸困难和晕厥等严重威胁生命的临床症状, 导致预后极差。外科瓣膜置换术能够明显改善患者的生存质量及预后。然而, 传统的外科手术可能导致严重的并发症, 尤其是高龄、 术前合并其他疾病的患者, 因此, 超过30%的患者未能接受手术治疗。为解决这一问题, 经皮穿刺导管介入的微创技术应运而生。经导管主动脉瓣植入 （TAVI） 术是将人工生物瓣膜嵌入导管内并在病变的主动脉瓣原位释放的技术。多项临床研究已经表明, TAVI手术能够显著降低病死率, 目前全球已完成超过40万例。随着临床数据的积累, TAVI手术的适应证有望进一步扩大。在欧美发达国家已经积累了较为丰富经验的基础上, TAVI介入技术自2010年开始引进我国, 初步临床疗效确切, 为我国此类患者点燃了生命的希望。虽然现阶段TAVI手术并不是主动脉瓣疾病治疗的金标准, 但微创或无创的治疗方法代表着未来瓣膜外科的发展方向。     

不同起搏方式对心脏结构的影响

心脏起搏可改善心动过缓患者症状 ,防止心脏停搏 ,延长寿命 ,被广泛运用于临床 ,然而不同的起搏方式对心脏的影响并不相同 ,为了解不同起搏方式对长期心脏起搏患者心脏结构的影响 ,我们比较了起搏治疗对左心结构的影响 ,报告如下。资料和方法　患者 63例 ,诊断为窦性心动过缓、窦房阻滞和病态窦房结综合征、二度或三度房室传导阻滞或双束支传导阻滞 ,并伴头晕、乏力、晕厥等症状 ,心脏功能衰竭。 3 8例行VVI起搏 ,2 5例行DDD起搏 ,采用锁骨下静脉穿刺置入起搏器。住院期间行体表心电图、胸片、超声心动图、Holter检查 ,起搏器置入后定期…     

直接经皮冠状动脉介入治疗急性心肌梗死的疗效观察

目的 探讨直接经皮冠状动脉介入（PCI）治疗急性心肌梗死（AMI）的疗效及安全性。方法 56例AMI患者，均先进行选择性冠状动脉造影，根据造影结果结合心电图确定梗死相关动脉（IRA），对IRA血流呈TIMIⅠ、Ⅱ级者行PCI。对患者急性期康复情况及心脏事件的发生进行观察并记录。结果 56例IRA为：前降支35支，右冠状动脉12支，回旋支9支。全部进行了直接PCI，共植入支架66个，成功率100％，IRA前向血流均达TIMIⅢ级，其中12例合并高度及Ⅲ度房室传导阻滞忠者均植入临时起搏器。PCI后38例胸痛完全缓解，18例大部分缓解，52例可见ST段明显回落，9例高度及Ⅲ度房室传导阻滞患者于手术后1～3d传导阻滞消失，2例遗留Ⅰ度房室传导阻滞，1例Ⅲ度房室传导阻滞患者术后2周安装了心脏永久起搏器，除1例患者手术后第2天死于顽固性心袁合并心室颤动外，其余患者住院期间均恢复良好，无心脏事件发生。结论 直接PCI治疗AMI安全、可靠。     

心脏瓣膜置换加直视下双极射频消融治疗持续性心房颤动

目的探讨心脏瓣膜置换和心内直视下同期双极射频消融治疗心瓣膜病合并持续性心房颤动的安全性和疗效。方法回顾性分析2010年4月至2013年8月心脏瓣膜病合并持续性心房颤动70例患者行心瓣膜置换术加改良冲洗式双极射频消融手术的临床资料,术中采用Medtronic Cardioblate 68000冲洗式双极射频消融系统进行消融。消融路径包括双侧肺静脉的环形隔离、左心耳切除、左右心房消融和Marshall 韧带切除;术后根据病情给予胺碘酮治疗3～6个月。结果70例患者手术均顺利完成,平均消融时间为（14±6） min,术后当天有62例恢复为窦性心律;其中6例分别于术后2周内发生阵发性心房颤动,经静脉持续泵入盐酸胺碘酮后5例转为窦性心律,1例于出院时仍为心房颤动心律;术后当天仍有6例为房颤心律。全组有2例围手术期出现Ⅲ度房室传导阻滞,出院前安装永久起搏器。全组无心脏穿孔,无手术死亡。患者平均住院时间为（12.3±2.1）d。术后平均随访（9±5）个月,术后6个月随访患者有82.8%（58/70）维持窦性心律,14.3%（10/70）仍为心房颤动,2.9%（2/70）为起搏心律。结论心内直视下同期改良冲洗式双极射频消融治疗心脏瓣膜病合并持续性心房颤动是一种简易、安全、有效的方法。     

射频消融治疗室上速20例报告

射频消融（RFCA）治疗房室折返性心动过速13例，其中1例术后1个半月复发，再次消融获成功，其成功率为92.3％。RFCA对5例房室结双径路（DAVNP）折返性心速患者进行房室结改良，成功地阻断了DAVNP的慢径传导，其中1例术后发生间隙性Ⅲ度房室传导阻滞（Ⅲ°AVB）。2例快速房颤（Af）及房扑（AF）行快径消融，形成Ⅲ°AVB，术后安装VVI起搏器．可见RFCA有效地根治了室上速的发作。     

重症心脏瓣膜病的外科治疗

目的为探讨重症心脏瓣膜病外科治疗的安全性、手术成功率、治疗效果的方法。方法对200例重症心脏瓣膜病患者进行了手术治疗，按重症心脏瓣膜病的诊断标准，均存在多项心脏瓣膜病外科手术的高危因素；其中单纯左房室瓣替换94例、单纯主动脉瓣替换10例、左房室瓣替换加主动脉瓣替换90例、右房室瓣替换3例、感染性心内膜炎赘生物清除加左房室瓣替换3例，并且进行了回顾性的分析。结果本组手术大部分取得良好恢复，并发症发生率25％（50／200），术后早期死亡率7％（14／200）。随访157例中，远期死亡8例。结论重症心脏瓣膜病外科手术的卉度症发生率较高，手术风险相对较高，但术前准备、麻醉平稳、术中对病变的纠治合理和注意并发症的预防等，仍能取得较好的疗效。     

Lidocaine-induced second-degree mobitz type II heart block

Lidocaine-induced atrioventricular (AV) conduction disturbances are an ill-defined phenomenon. Electrophysiological studies in both animal and human subjects have shown that therapeutic doses of lidocaine have no significant effect on AV nodal and His-Purkinje conduction time in the presence of intact AV conduction. Sporadic reports of accelerated AV conduction or complete heart block following lidocaine administration have been published. One case of Mobitz type II heart block has been reported in a patient with a prolonged QTc interval (0.61 sec) who was also receiving prenylamine. Electrophysiological studies designed to evaluate lidocaine's effects on AV conduction present conflicting observations. We report a case of Mobitz type II heart block following therapeutic doses of lidocaine in the absence of acute myocardial infarction or concomitant cardioactive drug administration. This case, in conjunction with other reported data, suggests the occurrence of lidocaine-induced AV block to be unpredictable. Although its occurrence may be infrequent, the severity of these reactions warrants careful selection and monitoring of patients who are to receive lidocaine.     

经皮导管人工主动脉瓣植入手术

摘 要：在有严重合并症的主动脉瓣狭窄患者,经导管人工主动脉瓣植入术（transcatheter aortic valve implantation , TAVI）治疗主动脉瓣狭窄是一项新兴的介入治疗方法。该手术采用经外周动脉或者经心尖的途径,通过导管在原位的主动脉区域置入一个缝合在金属环的上的生物瓣膜。随着更多的临床研究和技术的改善,适应症会逐渐增加,手术风险也会进一步降低。     

经食管超声心动图在无球囊预扩张经导管主动脉瓣置换术中的临床意义

目的 比较经食管超声心动图(TEE)在球囊预扩张(BPD)和无球囊预扩张经导管主动脉瓣置换术(TAVI)中的差异,评估经食管超声心动图在无球囊预扩张经导管主动脉置换术中的临床意义.方法 回顾性分析2016年1月至2019年1月在郑州市第七人民医院行TAVI的149例重度主动脉狭窄病人的经食管超声心动图资料,比较主动脉环及根部、瓣叶活动度和钙化程度以及瓣膜面积等数据,从而评估经食管超声心动图在无球囊预扩张经导管主动脉置换术中的临床意义.结果 病人年龄(82.73±5.26)岁,59例病人接受了无球囊预扩张经导管主动脉瓣置换术.主动脉瓣面积(0.61±0.15)cm2,主动脉瓣环长径(22.14±2.31)mm.共14例病人在TAVI术后出现瓣周漏,其中无球囊预扩张组5例,与球囊扩张组瓣周漏发生率差异无统计学意义.其余受访病人均未出现严重并发症.结论 经食管超声心动图可对心脏结构进行准确的测量,帮助选择无球囊预扩张TAVI的合适病人,对临床治疗具有重要的临床价值.     

The effects of slow channel blockers and beta blockers on atrioventricular nodal conduction

The PR interval on the electrocardiogram represents the time that it takes an impulse to travel through the atrium and atrioventricular (AV) conduction system to the ventricles. Normally, activation is slowest in the AV node, and variations in PR interval most commonly parallel changes in AV nodal activation time. The AV nodal conduction time and effective refractory period are rate dependent and, in adult humans, are usually prolonged with increasing atrial paced rates. In addition, alterations in autonomic tone effect AV nodal conduction as well as sinus rate. The effect is usually in the same direction but often to different degrees. In patients with normal AV nodal function, parasympathetic and sympathetic tone are balanced at rest, but in patients with abnormal AV conduction, the effect of the parasympathetic system is more marked. Drugs including the slow channel blockers and beta blockers, affect AV nodal function. Slow channel blockers inhibit the slow inward calcium current, which may prolong conduction and refractoriness in the AV node. However, whereas diltiazem and verapamil have been shown to prolong AV nodal conduction and refractoriness in humans, nifedipine, a potent vasodilator, cannot be used in doses large enough to affect the AV node. The increase in PR interval caused by verapamil is minimal, and at doses of less than 480 mg/d, AV block occurs infrequently. When AV block occurs, it is first degree block in most patients, and it is usually asymptomatic. The electrophysiologic effects of diltiazem are similar to those of verapamil. Beta blockers also have a negative dromotropic effect on the AV node. They prolong the AH interval and AV nodal refractory periods and may lengthen the PR interval. The prolonged PR interval rarely results in more than first degree AV block in patients receiving maintenance therapy. In selected patients, combination therapy with a slow channel blocker and a beta blocker rarely causes second-degree AV block.     

"Valve in valve" percutaneous aortic valve implantation for severe mixed bioprosthetic aortic valve disease

Transcatheter aortic valve implantation (TAVI) is an effective treatment for patients with severe aortic stenosis at high risk for surgical valve replacement. We present a case of successful, off-label transfemoral valve-in-valve implantation of the self-expandable Medtronic-CoreValve prosthesis in an inoperable elderly patient with structural deterioration of an existing bioprosthesis in the aortic position. This case illustrates that TAVI for a deteriorated aortic bioprosthesis is feasible in a patient who was not suitable for reoperation.     

Maintained prolongation of AV conduction time by acetylcholine

Although chronotropic responses to maintained cholinergic activation have been reported to fade during tonic vagal stimulation, discrepancy exists as to whether AV conduction behaves similarly. Since previous studies have examined only low grade AV block, we sought to more fully characterize the dromotropic responses to different degrees of maintained cholinergic activation. We used anesthetized mongrel dogs in which the nutrient artery supplying the AV node region was cannulated and perfused with either autologous blood or oxygenated Tyrode solution containing various concentrations of acetylcholine. Electrograms were recorded from the SA node, atrium, ventricle and His bundle. In ten of eleven animals, perfusion with high concentrations of acetylcholine for five min resulted in the production of complete heart block which was sustained for the duration of the infusion. Moderate concentrations of acetylcholine, perfused via the AV node artery, resulted in maintained second degree AV block in five of eight animals and oscillation between first and second degree block in the other three. Perfusion with lower concentrations of acetylcholine resulted in maintained prolongation of the AH interval, which appeared however, to be dependent upon continuous uninterrupted perfusion of the AV node artery with acetylcholine. These results suggest that, irrespective of the magnitude of the dromotropic response during acetylcholine perfusion, fading is not characteristic of AV conduction during maintained cholinergic activation. Thus acetylcholine affects chronotropic and dromotropic responses differently.     

Effect of DHP-218, a novel dihydropyridine phosphonate, on atrioventricular nodal conductivity compared with its vascular effect in dogs

The effect of DHP-218, a dihydropyridine phosphonate Ca2+ channel blocker, on atrioventricular (AV) nodal conductivity was compared with its vascular effect in dogs. In isolated, blood-perfused AV node preparations, a long-lasting increase in AV conduction time which culminated in second- or third-degree AV block at large doses occurred when DHP-218 was injected into the AV node artery, but not when injected into the artery that supplies the His-Purkinje-ventricular system. However, with DHP-218, a far longer-lasting increase in blood flow through both arteries occurred, and at smaller doses it occurred with little effect on AV conduction. In anesthetized, open-chest dogs of which heart rate was controlled at 150 beats/min, intravenous DHP-218 produced an initially rather quick and later very slowly developing and long-lasting fall in blood pressure. AV conduction time was prolonged only after the largest dose. The functional refractory period of the AV conduction system was rather shortened in all doses examined except for the largest dose. A marked increase in AV conduction time which culminated in third-degree AV block was seen in one of six dogs, only under conditions in which the heart was deprived of central neural control. These results indicate appreciable selectivity of DHP-218 for vasculature versus the AV node.     

Cardiovascular safety of low-dose fenfluramine in Dravet syndrome: a review of its benefit-risk profile in a new patient population

Objective: Dravet syndrome (DS) is a rare, treatment-resistant epilepsy syndrome for which current treatment regimens are often ineffective. Fenfluramine is currently in development for treatment of DS, based on reports in the 1980s and 1990s of its anti-epileptic activity in pediatric patients with intractable epilepsy. However, fenfluramine was withdrawn from global markets in 1997 following reports of its association with pulmonary hypertension and heart valve disease in adult patients treated for obesity. This review was conducted to assess cardiac safety of fenfluramine when used at lower doses for treatment of DS.

Methods: Pubmed was searched for clinical studies of fenfluramine in obese adults who reported incidence of heart valve disease. These data were reviewed against published results from Belgian patients with DS who have been treated with low-dose fenfluramine for up to 28 years.

Results: Nine controlled studies of fenfluramine and related compounds (dexfenfluramine and/or phentermine) which assessed incidence and severity of cardiac valve disease in 3,268 treated patients and 2,017 control subjects have been reported. Mild or greater aortic valve regurgitation was found in 9.6% of treated patients compared with 3.9% of control subjects, and moderate or greater mitral valve regurgitation was found in 3.1% of treated patients and 2.5% of control subjects. Nineteen DS patients have been treated for up to 28 years with 10–20?mg/day fenfluramine, with no clinical signs or symptoms of cardiac valve disease or pulmonary hypertension. Slight and clinically unimportant changes in valve structure have been seen on echocardiography in five patients at some time during the observation period.

Conclusions: A different benefit-risk relationship appears to be emerging when fenfluramine is used at low doses for extended periods in young patients with DS. Continued cardiac assessments during ongoing Phase 3 clinical trials will provide additional safety information for this potential new and effective treatment.     

The effects of indecainide, a new antidysrhythmic drug, on nodal tissues in the isolated rabbit heart

The effects of indecainide, previously shown to be a class 1c antiarrhythmic drug restricting fast inward current, have been studied on rabbit sinoatrial (SA) node and atrioventricular (AV) node. Indecainide at concentrations up to 2.9 mumol/L in 5 preparations did not produce a sinus bradycardia, nor reduce the maximum rate of rise of the intracellular action potential of sinus node cells, but it did antagonize the tachycardia induced by increasing the extracellular calcium concentration. Indecainide slightly prolonged AV conduction time [from 49.07 +/- 4.43 ms to 57.37 +/- 0.90 ms at 2.9 mumol/L (means +/- SEM in four preparations)], but this small delay could be attributed to slowing of conduction in atrial fibres leading to the node, rather than to an effect on the AV nodal cells themselves. It is concluded that indecainide does not block channels carrying inward calcium current in nodal tissues.