Research in Rhythm Group - Atrial fibrillation

Since 1988 a trial fibrillation is one of main and most successful research subjects of the department of Cardiology. First, we investigated in whom atrial fibrillation could be cured with antiarrhythmic drugs. However, success was limited and atrial fibrillation became permanent despite serial drug and cardioversion therapy in many . We, thus, performed the RACE study, a comparison between the long-term effects of acceptance of atrial fibrillation (rate control) versus restoration of sinus rhythm (rhythm control). We demonstrated that rate control, i.e. accepting atrial fibrillation, is not inferior to rhythm control in preventing cardiovascular morbidity and mortality. These data importantly changed clinical management of patients with atrial fibrillation. Very recently, we published a second study on rate control, the RACE II trial, in which we showed that during AF a higher heart rate can be allowed as during sinus rhythm. This again altered clinical management and the AF guidelines.

On the other hand, it should be noted that during rate control therapy morbidity and mortality still is significant. Even with oral anticoagulation the residual stroke or systemic embolism rate in patients with AF remains relatively high, ranging between 1.1 and 2.4% per year, depending on the presence of risk factors. Although r ecent studies show a trend towards reduction of events including stroke, further improvement of therapy to reduce AF associated events clearly is warranted. T he presence of AF seems one of the modifiable factors associated with death and cardiovascular morbidity in AF patients .

We therefore hypothesize that if effective and safe methods for maintaining sinus rhythm with fewer adverse effects will become available rhythm control therapy may become first choice therapy in more patients. A promising strategy might be catheter ablation combined with safe antiarrhythmic drugs and substrate oriented antiarrhythmic drugs with beneficial effects on outcome parameters.

Thus the main focus of research in the ‘rhythm group’ is:

1. Search for safe and effective rhythm control therapy , i.e. restoration of sinus rhythm and prevention of cardiovascular morbidity and mortality. We use upstream therapy and physical exercise (RACE 3 study) and ablation to investigate improvement of success of rhythm control therapy.
2. Search for mechanisms inducing atrial remodeling which triggers the onset and persistence of atrial fibrillation .
   a. C linically : assessing risk factors for atrial fibrillation including biomarkers, echocardiographic parameters and genetics.
   b. Experimentally: explore and perform analysis of microarray and proteomics data, cell isolation and growing of secretion-deficient yeast and ultimately the identification of (new) biomarkers involved in atrial stress.
   by using a cell model and hypertensive mice models (hypertension is the most frequently occurring associated disease of AF).
   U ltimately, we hope to find new drugs that may prevent AF, as is mentioned in aim 1.

For both subjects we look for enthusiastic students and research physicians.