The **ELEVATE-HFpEF Clinical Study** is a research project to test if a specialized pacemaker can help people with heart failure with preserved ejection fraction (HFpEF). HFpEF is a type of heart failure where the heart pumps normally, but the heart muscle is stiff and doesn't fill with blood as it should. In this study, all participants will get a pacemaker implanted. Some will have their pacemaker set to a personalized pacing rate based on their heart's function and height, while others will receive minimal pacing. **Key Points:** - Participants will have visits at 2, 6, 12, 14, 18, and 24 months, and yearly follow-ups after that. - The study lasts about 4.5 years. - Participants must be at least 40 years old, with specific heart health conditions and no severe obesity or recent heart surgeries. This study aims to see if the personalized pacing can improve symptoms and well-being in people with HFpEF. Participants will need to commit to regular visits and follow the study plan closely.