Atrial fibrillation

Atrial fibrillation is probably the most common cause of prolonged loss of biventricular pacing in CRT patients with a preserved atrioventricular conduction. These episodes are regularly associated with a rapid deterioration of hemodynamics through several combined mechanisms: increased heart rate, irregular ventricular rhythm with short diastole and LV filling disorder, loss of atrial systole and loss of biventricular resynchronization. When atrial arrhythmias can not be effectively controlled by the antiarrhythmic treatment, a pulmonary vein isolation procedure should be considered. The combined effect of ablation and resynchronization may result in a significant improvement of the patient’s symptomatology and in a reduction of ventricular volumes.

When rhythm control fails, ablation of the His-bundle is often necessary to enable the high percentages of biventricular pacing essential to the success of this therapy. His ablation is now part of the recommendations of the international guidelines for the treatment of patients with chronic AF and poorly controlled heart rate. After the ablation of the His-bundle, a rate responsive function must be programmed.

Remote monitoring of AF

There are multiple advantages of a remote monitoring in a CRT patient with episodes of atrial arrhythmia: 1) the diagnosis is confirmed by the analysis of the transmitted EGM; this allows eliminating false diagnoses of atrial arrhythmia (crosstalk, noise, etc.), 2) the diagnosis is quickly performed even if the patient is asymptomatic, 3) anticoagulant therapy could be introduced early to reduce the risk of stroke, 4) the treatment with an anti-arrhythmic may also introduced; the effectiveness of this treatment can be remotely  assessed on a daily basis through the remote monitoring follow-up.x