Progressive Ventricular Dysfunction Prevention in Pacemaker Patients (Prevent-HF)

Inclusion Criteria: Meet Class I and/or Class IIa implantation criteria for permanent cardiac pacing according to the guidelines given by the American College of Cardiology (ACC)/American Heart Association(AHA). Exclusion Criteria: Expected ventricle stimulation <80% of the time Impossibility of dual chamber stimulation in the absence of AF Severe heart failure (NYHA Functional class III-IV) previous to indication for pacing device implant Patient needs revascularization within 3 months Myocardial infarction in the last 3 months Cardiac surgery performed in the last 3 months Hypertrophic cardiomyopathy Constrictive pericarditis Bad echo window Previous system implanted (ICD or pacemaker) Aortic stenosis Patient has a mechanical right heart valve Patient <18 years Pregnancy Patient has medical conditions that would preclude the testing required by the protocol, or limit study participation Life expectancy <1year Patient is unwilling or unable to cooperate or give written informed consent. Patient is or will be inaccessible for follow-up at the study center. Patients who are participating or planning to participate in other clinical trials during the clinical study