Inclusion Criteria:  The patient must be ≥ 18 years of age. The patient must indicate their acceptance to participate in the study by signing an informed consent document. Patients with EF> 50% and indication for pacemaker implantation due to atrial-ventricular block according to current clinical guidelines.  Exclusion Criteria:  Inability to understand and sign the informed consent. Patients with severe comorbidities and life expectancy <1 year. Patients with severe cognitive impairment or other comorbidities resulting in dependence for basic activities of daily life. Patients who cannot come to our center to carry out the follow-up of the study.