Ventricular Tachycardia

Signs & symptoms

心律异常是指心跳速度或模式的改变——心脏可能跳动得太慢, too rapidly or irregularly. 当心脏跳动过慢时，输送到身体其他部位的血液就太少了. When the heart beats too quickly, 它不能完全填充，所以身体不能接受正常运作所需的血液量. 慢心率被称为心动过缓. 心率过快被称为心动过速.

The heart is made up of four chambers. 上面的腔室，称为心房，接收和收集血液. 下腔称为心室，将血液输送到全身. 心脏的各个腔室协同工作，将维持生命的血液输送到全身.

心律异常有几种类型, 有些发生在其中一个心房，称为心房, 另一些发生在心室，被称为心室.

心脏跳动过快或过慢都会导致:

• Lightheadedness or dizziness
• 心悸(跳、振或捶胸)
• Fatigue
• Chest pressure or pain
• Shortness of breath
• Fainting spells

有时根本没有任何症状. 如果不及时治疗，某些异常的心律可能会导致死亡. On the other hand, 有些心律失常是常见的，没有任何不利的十大赌博靠谱网络平台, so-called benign arrhythmias. 评估的目标之一是从良性形式中区分出严重的心跳障碍.

Diagnosis

如果你的十大赌博平台排行榜怀疑你可能有心律失常, 他或她将要求进行以下一项或多项诊断测试，以确定症状的来源.

• Electrocardiogram. 心电图(ECG或EKG)记录心脏的电活动. 被称为电极的小贴片被放置在你的胸部, arms and legs, 并通过导线连接到心电图机. 你的心脏的电脉冲被转换成一张移动的纸条上的波浪线, enabling doctors to determine the pattern of electrical current flow in the heart and to diagnose arrhythmias and heart damage.
• Holter monitor. 动态心电图监测仪是一种小型的便携式仪器，可以24小时佩戴. 它可以在您进行日常活动时连续记录您的心电图. 你将被要求记录你的活动和症状. 这种监视器可以检测到心律失常，可能不会显示在静息心电图上，只有几秒钟的记录.
• Exercise stress test. The exercise stress (treadmill) test enables physicians to record your heart's electrical activity which may not occur at rest.
• Event recorder. 事件记录仪(循环记录仪)是一种小型便携式跨电话监测器，可佩戴数周. 这种类型的录音机适合那些不经常出现症状的病人. 监视器将一个两分钟的录音“循环”到它的内存中，该内存不断被覆盖. When you experience symptoms, 你按下监视器上的“记录”按钮，它会存储相关的心电图材料条. 录音通过电话发送到24小时监测站，并直接传真给请求的十大赌博平台排行榜.
• Magnetic source imaging. 磁源成像(MSI)被用作对磁共振成像(MRI)的叠加。. The device senses weak magnetic fields generated by heart muscle tissue and localizes the arrhythmia non-invasively to save time during the invasive study.
• Tilt table test. Tilt table testing is used to diagnose fainting or black-out spells (vasovagal syncope) by trying to reproduce the black-out episodes. You will be tilted upright to about 60 degrees on a special table for a period of time with continuous recording of your ECG and blood pressure.
• The electrophysiology (EP) study. 脑电图研究可以让十大赌博平台排行榜获得更准确的信息, detailed information and, in many cases, provide treatment (i.e. 导管消融).

Treatments

这取决于你心律失常的类型和严重程度, 以及各种测试的结果，包括电生理研究, there are several treatment options. 你和你的十大赌博平台排行榜会决定哪一个是适合你的.

Medications

Certain anti-arrhythmic drugs change the electrical signals in the heart and help prevent abnormal sites from starting irregular or rapid heart rhythms.

Follow-up electrophysiology study

确保在住院两天或更长时间后药物能正常工作, 你可能会被带回实验室进行后续研究. 我们的目标是找到对你最有效的药物.

Implantable device (pacemaker)

所有植入式装置或起搏器都是根据“需求”工作的，用于治疗心律缓慢. They are small devices that are implanted beneath the skin below the collarbone and connected to a pace wire(s) positioned inside the heart via a vein; this delivers a small electrical impulse to stimulate the heart to beat when it is going too slow.

Catheter ablation

A technique pioneered at UCSF, 射频导管消融术破坏或破坏部分引起心律失常的电通路, 为可能对药物反应不佳的患者提供缓解, 或者不愿意或不能服药的人.

Catheter ablation involves threading a tiny metal-tipped wire catheter through a vein or artery in the leg and into the heart. Fluoroscopy, 它可以让心脏病专家在监视器上看到导管在血管中的移动, provides a road map. Other catheters, usually inserted through the neck, 包含电子传感器，以帮助找到导致短路的区域. The metal-tipped catheter is then maneuvered to each problem site and radiofrequency waves — the same energy used for radio and television transmission — gently burn away each unwanted strand of tissue. 当第一次尝试导管消融时, direct current shocks were used, 但研究人员后来开发了使用射频波——一种更精确的能量形式. 使用射频导管消融, 病人通常在一天内出院, compared to open heart surgery, 需要一个星期的住院治疗和几个月的康复.

比如沃尔夫-帕金森-怀特综合症, in which a hair-thin strand of tissue creates an extra electrical pathway between the upper and lower chambers of the heart, radiofrequency ablation offers a cure. It has become the treatment of choice for patients with that disorder who don't respond well to drug therapy or who have a propensity for rapid heart rates.

即使是可以用药物控制的心律失常, 该程序已被证明具有成本效益，因为它消除了需要住院治疗的药物失败. It also is an attractive option for elderly patients who are prone to suffer side effects from drug therapy and women of childbearing age who can't take medications because of potential health risk to the fetus.

虽然研究表明导管消融比药物治疗或手术更经济有效, 接受手术的患者在生活质量方面也有了显著的改善. A recent study of nearly 400 ablation patients with dangerously rapid heart rates — nearly a third of whom were considered candidates for open heart surgery — found that one month after the procedure 98 percent required no medication and 95 percent reported that their overall health had markedly improved. 加州大学旧金山分校的研究还发现，患者的工作能力有所改善, 锻炼身体，参加体育活动.

Internal cardioversion

Internal cardioversion for conversion of atrial fibrillation and atrial flutter to a normal sinus rhythm was developed here at UCSF Medical Center in 1991. Internal cardioversion is low energy electrical shock (1 to 10 joules) delivered internally in the heart through two catheters inserted in a vein in the groin and a small electrode pad applied to the chest. 这个过程由我们的电生理学家在电生理学实验室进行.

在心脏复律期间，给予短效镇静剂使病人昏昏欲睡. Currently, atrial flutter is successfully "cured" by radiofrequency catheter ablation; but treatment to restore atrial fibrillation to sinus rhythm has been the traditional use of medications and external cardioversion. External cardioversion is delivery of high energy shocks of 50 to 300 joules through two defibrillator pads attached to the chest. In some cases, external cardioversion has failed because the electrical current has to first travel through chest muscle and skeletal structures before reaching the heart. Internal cardioversion has been performed when medications and external cardioversion have failed to restore a patient's rhythm back to a normal sinus rhythm.

UCSF's success rate of converting a patient from atrial fibrillation to normal sinus rhythm with internal cardioversion has been 95 percent. 患者心房颤动的时间越短, 就越容易恢复到正常的心律, but even patients with long-standing chronic atrial fibrillation can be converted successfully to a normal rhythm through internal cardioversion. With internal cardioversion, our electrophysiology team was successful in converting a patient who had been in chronic atrial fibrillation for eight years.

植入式转复除颤器

植入式心律转复除颤器是为那些容易出现危及生命的快速心律的人设计的设备. 它比心脏起搏器稍大，通常被植入锁骨下的皮肤下. 它通过静脉与心脏内的除颤/起搏导线相连. 它有能力在检测到心率过快时对心脏进行电击. 当心脏跳动过慢时，它也能调节或刺激心脏.

Biventricular pace maker

The U.S. Food and Drug Administration (FDA) recently approved the first of a new type of pacemaker that paces both ventricles of the heart to coordinate their contractions and improve their pumping ability. 根据提交给FDA的测试结果，心脏再同步化治疗(CRT):

• 增加患者在无心力衰竭症状的情况下的日常活动量
• 延长心力衰竭患者的运动能力，以他们在6分钟内可以走的距离来衡量
• 根据标准测量，提高整体生活质量
• 促进心脏解剖结构的改变，改善心脏功能
• 减少患者在十大赌博平台排行榜花费的天数和住院总次数

CRT装置通过同时对左、右心室起搏来工作, 这能使肌肉收缩重新同步，提高虚弱的心脏的效率. In the normal heart, the electrical conduction system delivers electrical impulses to the left ventricle in a highly organized pattern of contractions that pump blood out of the ventricle very efficiently. 心脏增大引起的收缩期心力衰竭(扩张型心肌病), this electrical coordination is lost. 不协调的心肌功能导致血液从心室排出效率低下.