Ablation of atrial fibrillation - safety, efficacy and long-term effects

Project: Dissertation

Project Details


Atrial fibrillation is one of the most common types of cardiac arrhythmias and is frequently causes disabling symptoms in the form of palpitations, decreased exercise capacity and increased anxiety. Atrial fibrillation also confers a 5-fold risk for thromboembolic stroke, as well as a two-fold higher risk for congestive heart failure, and mortality. Atrial fibrillation is also associated with additional neurological disorders, including cognitive impairment and dementia.

The initiation of anticoagulation in patients with atrial fibrillation with an elevated risk of a thromboembolic event is the first cornerstone of treatment and has been shown to substantially decrease the risk of thromboembolic stroke in patients with atrial fibrillation. The second cornerstone of atrial fibrillation treatment is the decision to aim for ‘rate or rhythm’ control – i.e., to either accept the presence of the arrhythmia (but control the rate) or to initiate measures to eliminate the arrythmia (to control the rhythm). The latter strategy has more recently come to include catheter ablation. Catheter ablation of atrial fibrillation was introduced as a potentially curative treatment of the
arrythmia in 1998. The treatment aims to electrically isolate the pulmonary
veins from the rest of the left atrium (hence the name ‘pulmonary vein isolation’), thereby eliminating the effect of the initiating drivers. Although the procedure is not without risk, the rate of periprocedural stroke being one percent and the rate of pericardial effusion is in the same range, it
is well established that catheter ablation of atrial fibrillation is the most effective way to achieve long-term sinus rhythm. In agreement with this, the main indication for catheter ablation of atrial fibrillation according to the present clinical guidelines is symptomatic atrial fibrillation.

However, several researchers have hypothesized that catheter ablation of atrial fibrillation offers more than ‘just’ symptom relief, based on the fact that the establishment of stable sinus rhythm ought to affect other aspects of the morbidity associated with atrial fibrillation. Randomized clinical trials examining this have in large part fallen short due to slow recruitment and sizeable cross-over between treatment groups. However, a smaller randomized trial indicates that catheter ablation of atrial fibrillation may improve survival in patients with concomitant heart failure. There are also some register data available indicating that catheter ablation of atrial fibrillation may lower the risk of stroke and dementia, but these studies are hampered by considerable limitations due to
incomplete data, selection bias and/or poor matching of controls.

In conclusion, the preliminary data indicate that catheter ablation of atrial fibrillation offer benefits beyond symptom relief hold promise, but the data are scarce and need to be confirmed in subsequent studies. Given the nature of the procedure and its already established benefits, complete, population-based register data offer a unique possibility to provide valuable insights.

The current project will explore the pre- peri- and post procedure safety and efficacy of ablation of atrial fibrillation.
The research questions that will be addressed include:
1. Does pre-procedural transesophageal echocardiography and to the safety of the procedure?
2. Does ablation of atrial fibrillation have significant effect beyond symptom relief?
3. Can the efficacy of the ablation procedure be predicted using periprocedural, invasive estimates of atrial fibrillatory characteristics?
4. What are the overall characteristics of catheter ablation of arrhythmia in a national registry? Has the efficacy and safety increased over time?
Effective start/end date2022/03/01 → …