This study aims to evaluate the clinical impact of an optimized pacing strategy in patients with heart failure.
* Intervention: Adjustment of the pacemaker lower rate limit to an individualized, hemodynamically optimized heart rate.
* Primary Endpoint: Heart failure symptoms, assessed by the Kansas City Cardiomyopathy Questionnaire score.
* Hypothesis: In patients with heart failure requiring permanent pacing, an optimized pacing strategy will lead to a significant improvement in heart failure symptoms (Kansas City Cardiomyopathy Questionnaire score) at 12 months compared with the conventional pacing strategy.