心律不整 英文

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  • Cardiac arrhythmias can be classified by site of origin:

  • - Sinus rhythms originate from the sinoatrial node, or SA node

  • - Atrial rhythms originate from the atria - Ventricular rhythms originate from the ventricles.

  • Sinus rhythm is the normal rhythm of the heart set by its natural pacemaker in the SA node.

  • In a healthy heart, the SA node fires 60 to 100 times per minute resulting in the normal

  • heart rate of 60 to 100 beats per minute.

  • The most common variations of sinus rhythm include:

  • - Sinus bradycardia: when the SA node fires less than 60 times per minute resulting in

  • a slower heart rate of less than 60 beats per minute.

  • and - Sinus tachycardia: when the SA node fires

  • more than 100 times per minute generating a faster heart rate of greater than 100 beats

  • per minute.

  • Sinus bradycardia and sinus tachycardia may be normal or clinical depending on the underlying

  • cause.

  • For example, sinus bradycardia is considered normal during sleep and sinus tachycardia

  • may be normal during physical exercises.

  • Cardiac arrhythmias that originate from other parts of the atria are always clinical.

  • The most common include: atrial flutter, atrial fibrillation and AV nodal re-entrant tachycardia.

  • These are forms of supraventricular tachycardia or SVT.

  • Atrial flutter or A-flutter is caused by an electrical impulse that travels around in

  • a localized self-perpetuating loop, most commonly located in the right atrium.

  • This is called a re-entrant pathway.

  • For each cycle around the loop, there is one contraction of the atria.

  • The atrial rate is regular and rapid - between 250 and 400 beats per minute.

  • Ventricular rate, or heart rate, however, is slower, thanks to the refractory properties

  • of the AV node.

  • The AV node blocks part of atrial impulses from reaching the ventricles.

  • In this example, only one out of every three atrial impulses makes its way to the ventricles.

  • The ventricular rate is therefore 3 times slower than the atrial rate.

  • This is an example of a “3 to 1 heart block”.

  • Ventricular rate in A-flutter is usually regular, but it can also be irregular.

  • On an ECG atrial flutter is characterized by absence of normal P wave.

  • Instead, flutter waves, or f-waves are present in saw-tooth patterns.

  • Atrial fibrillation is caused by multiple electrical impulses that are initiated randomly

  • from many ectopic sites in and around the atria, commonly near the roots of pulmonary

  • veins.

  • These un-synchronized, chaotic electrical signals cause the atria to quiver or fibrillate

  • rather than contract.

  • The atrial rate during atrial fibrillation can be extremely high, but most of the electrical

  • impulses do not pass through the AV node to the ventricles, again, thanks to the refractory

  • properties of the cells of the AV node.

  • Those do come through are irregular.

  • Ventricular rate or heart rate is therefore irregular and can range from slow - less than

  • 60 - to rapid -more than 100 - beats per minute.

  • On an ECG, atrial fibrillation is characterized by absence of P-waves and irregular narrow

  • QRS complexes.

  • The baseline may appear undulating or totally flat depending on the number of ectopic sites

  • in the atria.

  • In general, larger number of ectopic sites results in flatter baseline.

  • AV nodal re-entrant tachycardia or AVNRT is caused by a small re-entrant pathway that

  • involves directly the AV node.

  • Every time the impulse passes through the AV node, it is transmitted down to the ventricles.

  • The atrial rate and ventricular rate are therefore identical.

  • Heart rate is regular and fast, ranging from 150 to 250 beats per minute.

  • Ventricular rhythms are the most dangerous.

  • In fact, they are called lethal rhythms.

  • Ventricular tachycardia or V-tach is most commonly caused by a single strong firing

  • site or circuit in one of the ventricles.

  • It usually occurs in people with structural heart problems such as scarring from a previous

  • heart attack or abnormalities in heart muscles.

  • Impulses starting in the ventricles produce ventricular premature beats that are regular

  • and fast, ranging from 100 to 250 beats per minute.

  • On an ECG V-tach is characterized by wide and bizarre looking QRS complexes.

  • P wave is absent.

  • V-tach may occur in short episodes of less than 30 seconds and cause no or few symptoms.

  • Sustained v-tach lasting for more than 30 seconds requires immediate treatment to prevent

  • cardiac arrest.

  • Ventricular tachycardia may also progress into ventricular fibrillation.

  • Ventricular fibrillation or v-fib is caused by multiple weak ectopic sites in the ventricles.

  • These un-synchronized, chaotic electrical signals cause the ventricles to quiver or

  • fibrillate rather than contract.

  • The heart pumps little or no blood.

  • V-fib can quickly lead to cardiac arrest.

  • V-fib ECG is characterized by irregular random waveforms of varying amplitude, with no identifiable

  • P wave, QRS complex or T wave.

  • Amplitude decreases with time, from initial coarse v-fib to fine v-fib and ultimately

  • to flatline.

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心律失常 (Cardiac Arrhythmias)
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    alex 發佈於 2021 年 01 月 14 日

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心律不整是什么?

心律不整指的控制心跳的電流訊號延遲或遭阻擋、竇房結不能正常運作,或電流訊號無法正常傳遞至心臟,便可能發生心律不整。 此外,若心臟不該產生信號的部位產生了電流訊號,打亂了特殊神經細胞的信號傳遞,破壞正常的心跳頻率,也可能引發心律不整。 常見心律不整的原因如下: 基因

心跳不规律是什么原因?

心脏原因:心脏的传导系统病变是导致心律失常最常见原因;心律失常还可以继发于各种器质性心脏病,如:高血压、冠心病、急性心肌梗塞、 心肌病、心肌炎、风湿性心脏病、心力衰竭等; 其他原因:水、电解质及酸碱平衡紊乱,全身性或其他系统疾病,如内分泌疾病,神经系统疾病,代谢性疾病及创伤等。

心律失常严重吗?

心律失常的病情进一步发展恶化,严重者甚至会猝死,尤其是冠心病患者猝死率会更高。 对于心肌炎后遗症患者而言,出现心律失常的几率也是很大的,且轻重程度不一,常见的有:早搏、心动过速、传导阻滞等,缠绵难愈的各种心律失常对他们的心脏功能有一定的影响,需要积极治疗。

心律不正怎么办?

这可能包括综合以下方式的治疗:.
改变生活方式: 戒烟 避免从事会引发心跳不规律的活动 ... .
药物: 用于控制心率的抗心律失常药物 ... .
为尝试控制心律失常及恢复正常心率而进行的手术: 起搏器、除颤器和心脏植入物。 ... .
导管消融手术通常可治愈心律失常,主要在完成电生理检查之后以及当用药无效或不方便时执行。 手术的进行方式如下:.