Cardioversion (Latin: cardio = heart, vertere = to turn) is a procedure in which the sinus rhythm of the heart is restored. It is used for cardiac arrhythmias such as atrial fibrillation and is intended to enable a return to a steady pulse.
Below you will find further information and selected specialists for cardioversion.
Cardioversion is the treatment of cardiac arrhythmia in which an irregular heartbeat is converted back into a regular one. "Cardio-" stands for heart and "-version" for return. Cardioversion can be carried out using special medication or electricity.
Drug-induced cardioversion involves the use of so-called antiarrhythmic drugs, such as flecainide, amiodarone and propafenone. "Anti-" here means against and "arrhythmia" is an irregular heartbeat.
The application of electricity is also referred to as electrical cardioversion, which can be performed externally (externally) or internally (internally) using special pacemakers.
The so-called sinus node sets the rhythm for a healthy, regular heartbeat, which is why the normal heartbeat is also called sinus rhythm. The sinus node is a comma-shaped structure approximately 3 mm wide and 10 mm long and is located in the right atrium of the heart. It is a kind of clock that sends electrical signals to the four heart cavities (two atria and two ventricles) and thus controls the contractions of the heart muscle. A sinus rhythm corresponds to a steady pulse and is therefore the normal state. Depending on physical activity, however, the number of heartbeats per minute varies between 40 beats (in deep sleep) and over 180 beats during maximum physical exertion. This is also controlled by the sinus node.
Irregular heartbeats occur when the rhythm is out of sync. In these cardiac arrhythmias, the actual heartbeat continues, but without the necessary excitation control via the sinus node. This may be because other areas of the heart take over the electrical impulses to excite the heart and "trump" the sinus node, so to speak. However, it is often also due to the sinus node becoming ill.
Atrial fibrillation is one of the most common forms of cardiac arrhythmia. The impulse for the heart rate originates from other different locations in the atria.
There are many reasons for the development of atrial fibrillation, which is often a combination of
A heart attack is also one of the most important risk factors for the development of cardiac arrhythmia.
Cardioversion is necessary in an emergency if sudden cardiac arrhythmia leads to loss of consciousness and fainting. This is the case with ventricular fibrillation, for example, which can occur in the event of a heart attack. Functionally, ventricular fibrillation causes cardiac arrest, as the blood can no longer be pumped out of the heart effectively. Strictly speaking, however, it is not a cardiac arrest, but a cardiac arrest caused by continuously active heart muscles that make it impossible for the heart to function properly. In these emergency situations, external cardioversion is used, for which a defibrillator ("shock generator") is used.
There are also elective, i.e. planned, indications for cardioversion. The most common cause is chronic atrial fibrillation that persists over a long period of time. This leads to permanently uncoordinated activity of the heart muscle and the effectiveness with which the blood is pumped into the vessels is reduced. Many sufferers experience this as palpitations and also feel the irregularity of the heartbeats physically. Signs of weakness and dizziness as well as nausea and restlessness are also possible. If these signs are present, cardioversion should be discussed, especially in younger and active patients.
Pure atrial fibrillation is not usually dangerous, but there is a significantly increased risk of clots (medically known as thrombi ) forming in the irregularly beating atria. Thrombus formation occurs particularly in the area of protrusions of the atria.
The reason for this is the slower speed at which the blood flows. These clots can eventually be carried away with the blood flow and washed away into an important body artery. This is called an embolism. Examples of this are a sudden vascular occlusion in the leg, which becomes noticeable through a pronounced feeling of cold, or a stroke, when the clot is carried upwards into the brain.
In order to prevent an acute stroke, anticoagulation (Latin: coagulare = to clot), an anticoagulant therapy, is carried out. This measure is carried out for several weeks, often years, depending on the individual indication and personal risk profile of the patient.
The diagnosis and non-surgical treatment of heart disease is the responsibility of specialists in internal medicine and cardiology. These specialists (cardiologists) carry out drug therapies and catheter-based treatments safely. Non-surgical therapy therefore includes all invasive (with catheters) and drug-based measures with the exception of heart surgery, which is performed by heart surgeons.
Not every patient with atrial fibrillation needs cardioversion. Many patients have had atrial fibrillation for years without serious problems. However, as atrial fibrillation is associated with an increased risk of stroke, the vast majority of patients are treated with an anticoagulant drug. Cardioversion, i.e. the establishment of a regular sinus rhythm, is indicated for patients with recent onset of atrial fibrillation, a very fast heartbeat(tachycardia) or heart pain(myocardial ischemia) due to circulatory disorders of the heart muscles.
If the atrial fibrillation does not stop on its own within 48 hours, cardioversion is recommended. This can be done either with medication or electrically.
In drug therapy, an attempt is made to restore sinus rhythm using an antiarrhythmic drug. The aim of this form of medication is to achieve regular cardiac activity.
If the desired state cannot be achieved with drug cardioversion, electrical cardioversion is performed. This involves applying a direct current pulse to the chest wall using a defibrillator.
The treatment is painless, takes only a few minutes and is performed under a brief general anesthetic. During electrocardioversion, the patient is monitored by an ECG (electrocardiogram to record heart activity). After the treatment, a further appointment is required to check that the sinus rhythm has been maintained.
By BruceBlaus. When using this image in external sources it can be cited as: Blausen.com staff (2014)."Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436. - Own work, CC BY 3.0, Link
Patients who already have a pacemaker may not be cardioverted. However, there is the option of a special probe setting for the pacemaker, which makes lower-risk treatment possible.
A high risk is posed by thrombi in the atrium, which regularly occur during atrial fibrillation. It is possible for them to become detached during electrical cardioversion and lead to an embolism. For this reason, transesophageal echocardiography (cardiac ultrasound) is usually performed immediately before cardioversion. In this examination, known as "swallowing echo", a probe is inserted via the oesophagus and advanced to the stomach. The oesophagus is positioned directly behind the heart, so the swallowing echo can provide accurate images from here, which provide information about any thrombi in the atrium. If thrombi are detected, cardioversion must be performed under special blood thinning.
A fundamental risk lies in the unintentional triggering of additional cardiac arrhythmias by the defibrillation itself. This would worsen the condition instead of improving it.
Cardioversion is generally considered to be helpful and promising for atrial fibrillation, especially if it cannot be controlled with medication and leads to symptoms.
The long-term success of cardioversion can only be determined on a case-by-case basis and is at least more likely with the additional administration of rhythm-preserving medication .
Nevertheless, atrial fibrillation often recurs even after cardioversion. It is possible to repeat the treatment in this case, but even a repeat does not guarantee success.
The longer the arrhythmia exists, the more difficult it is to maintain sinus rhythm in the long term.
If no lasting success is achieved despite multiple cardioversions and drug treatment, catheter ablation may be possible. This involves sclerosing certain areas in the tissue of the heart muscle in order to permanently prevent further impulse disturbances. Here too, the chances of success vary and must be considered on an individual basis.
The Leading Medicine Guide's quality assurance is ensured by the following acceptance prerequisites.
