Tachycardia: Difference between revisions

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====Management:====
====Management:====
The management of AF consist of several key targets. Firstly, any underlying potential reversible cause of AF should be treated. Secondly, care should be taken to prevent the complications of AF. This means that adequate oral-anticoagulation should be initiated and rate control should be started to reduce heart rate. Thirdly, symptoms should be treated with medical or invasive therapy. There are two strategies to reduce symptoms of AF. Rate control is a strategy were Studies have shown no benefit of rhyhtm control over rate control, thus the selection of strategy is mainly dependent of patient and atrial fibrillation characteristics. Independent of the treatment strategy, proper anti-coagulation is important and necessary in patients with risk factors.<Cite>Camm2012,Camm2010</Cite>
The management of AF consist of several key targets. Firstly, any underlying potential reversible cause of AF should be treated. Secondly, care should be taken to prevent the complications of AF. This means that adequate oral-anticoagulation should be initiated and rate control should be started to reduce heart rate. Thirdly, symptoms should be treated with medical or invasive therapy. There are two strategies to reduce symptoms of AF. Rate control is a strategy were a reduction of ventricular heart rate is the main goal. In rhythm control the aim is to maintain sinus rhythm and prevent recurrences of AF.  
* <B>Rate control:</b> In atrial fibrillation the ventricle can have a fast irregular rate that can be difficult to tolerate by a patient. On of the strategies in managing atrial fibrillation is to control ventricular rate <120bpm. In this strategy no attempt is made to achieve sinus rhythm. This is the only treatment option in patients with permanent atrial fibrillation.  Due to the fast irregular ventricular rate a dilated tachycardiomyopathy can develop and proper rate control can revert these ventricular changes. Rate control can be achieved with beta-blockers, Ca-antagonist and digoxine.
* <B>Rate control:</b> In atrial fibrillation the ventricle can have a fast irregular rate that can be difficult to tolerate by a patient. On of the strategies in managing atrial fibrillation is to control ventricular rate <120bpm. In this strategy no attempt is made to achieve sinus rhythm. This is the only treatment option in patients with permanent atrial fibrillation.  Due to the fast irregular ventricular rate a dilated tachycardiomyopathy can develop and proper rate control can revert these ventricular changes. Rate control can be achieved with beta-blockers, Ca-antagonist and digoxine.
** <b>Invasive treatment:</b>  
** <b>Invasive treatment:</b>  
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*** <b>Catheter ablation:</b> Medical therapy is not always sufficient to maintain sinus rhythm. In the last decade of 20th century it was discovered that atrial fibrillation is triggered from the pulmonary veins and that selective ablation of these trigger sites can reduce atrial fibrillation recurrence. As this technique evolved it is now common to ablate an area around the pulmonary veins to isolate them from the atrial tissue. The left atrium is approached through the inter-atrial septum and with the use of imaging and electrocardiographic signals a 3D map is made to navigate the atria. The pulmonary vein isolation can be performed with multiple energy sources. This is a difficult and long procedure, that depending on the technique used has (severe) complications. The success rate of the procedure varies on the experience of the operator (40-60%). Often the success rate can be increased by performing multiple procedures.  
*** <b>Catheter ablation:</b> Medical therapy is not always sufficient to maintain sinus rhythm. In the last decade of 20th century it was discovered that atrial fibrillation is triggered from the pulmonary veins and that selective ablation of these trigger sites can reduce atrial fibrillation recurrence. As this technique evolved it is now common to ablate an area around the pulmonary veins to isolate them from the atrial tissue. The left atrium is approached through the inter-atrial septum and with the use of imaging and electrocardiographic signals a 3D map is made to navigate the atria. The pulmonary vein isolation can be performed with multiple energy sources. This is a difficult and long procedure, that depending on the technique used has (severe) complications. The success rate of the procedure varies on the experience of the operator (40-60%). Often the success rate can be increased by performing multiple procedures.  
*** <b>Surgical treatment:</b> Surgery is a more invasive, but more effective modality to treat atrial fibrillation. The classical cut and sew Maze procedure is a open chest procedure that requires extra-corporeal circulation. In this procedure the atrium is cut and sewn again to compartmentalize the atrium en therefore prevent the atrium maintaining atrial fibrillation. In recent years a less invasive procedure has developed to treat atrial fibrillation. This minimal invasive surgery is performed through thoractomy or thoracoscopy and is performed on a beating heart. A pulmonary vein isolation is performed with a clamp and if patients have persistent atrial fibrillation additional left atrial lessions are made on the atrium to compartmentalize the atrium. Finally the left atrial appendage is removed to reduce the occurrence of stroke. This procedure has a success rate of 68% after one year.
*** <b>Surgical treatment:</b> Surgery is a more invasive, but more effective modality to treat atrial fibrillation. The classical cut and sew Maze procedure is a open chest procedure that requires extra-corporeal circulation. In this procedure the atrium is cut and sewn again to compartmentalize the atrium en therefore prevent the atrium maintaining atrial fibrillation. In recent years a less invasive procedure has developed to treat atrial fibrillation. This minimal invasive surgery is performed through thoractomy or thoracoscopy and is performed on a beating heart. A pulmonary vein isolation is performed with a clamp and if patients have persistent atrial fibrillation additional left atrial lessions are made on the atrium to compartmentalize the atrium. Finally the left atrial appendage is removed to reduce the occurrence of stroke. This procedure has a success rate of 68% after one year.
Studies have shown no benefit of rhyhtm control over rate control, thus the selection of strategy is mainly dependent of patient and atrial fibrillation characteristics. This means that, since rate control is easier to achieve, rate control should be the initial strategy in all patients, especially in old patient and patients with no or few symptoms of atrial fibrillation. The target heart rate to achieve in rest is <110 beats per minute. In patients with persistent complaints of atrial fibrillation rhythm control can be initiated on top of rate control. Young patients with paroxysmal atrial fibrillation and no underlying heart disease might benefit from early (invasive) rhythm control to halt progression of the disease. However, independent of the treatment strategy, proper anti-coagulation is important and necessary in patients with risk factors.<Cite>Camm2012,Camm2010</Cite>
* '''Anticoagluation treatment:''' Proper anti-coagulation is important in patients with atrial fibrillation to reduce the occurence of stroke. In patient with atrial fibrillation the indication of anti-coagulation is based on certain risk-factors a patients has. A score is created to fascilitate this descision making. The CHADS<sub>2</sub>VASc2 score incorporates the following risk factors. If a patient has 2 points or 1 major point anti-coagulation with coumarins or other anticoagulation drugs (dabigatran, rivaroxiban) is indicated if no strong contra-indication exist. If a patient has no indication for anti-coagulation no medication is necessary.
* '''Anticoagluation treatment:''' Proper anti-coagulation is important in patients with atrial fibrillation to reduce the occurence of stroke. In patient with atrial fibrillation the indication of anti-coagulation is based on certain risk-factors a patients has. A score is created to fascilitate this descision making. The CHADS<sub>2</sub>VASc2 score incorporates the following risk factors. If a patient has 2 points or 1 major point anti-coagulation with coumarins or other anticoagulation drugs (dabigatran, rivaroxiban) is indicated if no strong contra-indication exist. If a patient has no indication for anti-coagulation no medication is necessary.


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