Plasma Aldosterone Levels and Atrial Fibrillation Reduction (ALDO-AF Study)

Atrial fibrillation (AF) is the most common cardiac arrhythmias with a constantly growing prevalence. Two main techniques are used today to restore sinus rhythm: electrical cardioversion and radiofrequency ablation.

Radiofrequency ablation has become a recognized and effective treatment of AF. Despite a relatively high success rate (about 80%), a substantial number of patients require a second procedure to obtain sinus rhythm. Many publications have led to the study of predictors of failure of this ablation factors (BMI, uncontrolled hypertension, size of the OG...) but to date no parameter is reliable and usable in daily practice.

It is the same for electrical cardioversion. Despite a relatively high immediate success rate of approximately 80%, a significant number of patient relapse arrhythmia in short and long term. Many publications have led to the study of predictive factors of failure (seniority and type of AF, uncontrolled hypertension, size of the OG, mitral valve disease...) but so far the results are disappointing.

In AF patients with heart disease underlying, it has been well demonstrated that the renin-angiotensin system (RAAS) was strongly activated. In addition, it is now well established that elevated plasma aldosterone as in primary hyperaldosteronism is associated with a significantly increased risk of occurrence of cardiovascular events. The high plasma concentrations were also highlighted in the acute phase of myocardial infarction, or heart failure and are associated with an increase in major cardiovascular event rate, especially arrhythmias. In some experimental models of heart failure, it has been demonstrated a suppression of the occurrence of spontaneous FA by an anti-aldosterone treatment. The arrhythmogenic effect of aldosterone has also been shown in animal models. All these results indicate a potential role of aldosterone in the genesis of an arrhythmogenic substrate and the FA.

The hypothesis of this study is that aldosterone plasma levels in pre-reduced patients is predictive of recurrence risk of atrial fibrillation or other supraventricular tachycardias (flutter or atrial tachycardia) after FA reduction, either in using a radiofrequency ablation or via electrical cardioversion.