ELEVATE-HFpEF Clinical Study

Inclusion Criteria

• Age ≥ 40 years
• Documented EF ≥50% within the preceding 12 months
• HFpEF defined as:

• Documented worsening HF episode (either HF hospitalization or documented urgent clinic visit for HF with intravenous diuretics) within 12-months prior to baseline visit OR
• Dyspnea on exertion and New York Heart Association (NYHA) ≥ class II symptoms AND AT LEAST ONE OF THE FOLLOWING CRITERIA:

• Interstitial / pulmonary edema on prior chest imaging in the last year AND current loop diuretic use for heart failure
• Elevated NT-proBNP in the last year defined as >400 pg/m for patients with no AF or paroxysmal AF, or >900 pg/ml for patients with ≥persistent AF
• Mean pulmonary capillary wedge pressure (PCWP) ≥15 mm Hg or LVEDP ≥16 mm Hg at rest on cardiac catheterization OR pulmonary artery diastolic and wedge pressure (PADP) ≥15 mm Hg at rest on implantable monitor (e.g., CardioMEMs)
• Echo criteria defined by ≥2 of:

• LV wall thickness ≥ 12 mm
• LV mass index (BSA indexed LVH): sex at birth male >115 g/m2, sex at birth female >95 g/m2
• Relative wall thickness ≥0.42
• E/e' ≥15 in sinus rhythm (or > 11 in the setting of atrial fibrillation) OR septal \<7 cm/s or lateral e' \<10cm/s
• Tricuspid regurgitation (TR) velocity >2.8 m/s
• Left atrial (LA) enlargement, defined by LA volume index >34 ml/m2
• Patient is on stable guideline indicated HF medical therapy (Class I recommendations) for at least 30 days
• Patient's average heart rate on baseline ambulatory electrocardiographic monitor is at least 5 bpm lower than their calculated personalized cardiac pacing rate (e.g. if a patient's personalized cardiac pacing rate is 70 bpm and their average heart rate on the ambulatory electrocardiographic monitor is less than or equal to 65 bpm the patient is eligible)
• Patient is willing and able to adhere to the protocol (e.g., patient is able to ambulate independently at baseline).

Exclusion Criteria

• Improved or recovered EF (i.e., prior LVEF\<50%)
• Patient has a previously implanted, currently implanted, or is intended to have implanted a cardiac implantable electronic device capable of delivering pacing (e.g., pacemaker, implantable cardioverter defibrillator (ICD), cardiac resynchronization therapy (CRT))
• Current pregnancy (requirement for negative pregnancy test may vary by jurisdiction)
• Average heart rate \<50 bpm or symptomatic bradycardia
• Acute coronary syndrome (including MI), cardiovascular surgery, or urgent percutaneous coronary intervention (PCI) within the 3 months prior to baseline visit or an elective PCI within 30 days prior to baseline visit.
• Current acute decompensated HF requiring intravenous diuretics, vasodilators and/or inotropic drugs.
• Severe obesity defined as BMI >45.
• Persistent, long-standing persistent, or permanent atrial fibrillation (AF) with an average heart rate \<50 bpm or evidence of ventricular pauses exceeding 6 seconds
• Planned AF ablation
• Infiltrative cardiomyopathies (e.g., amyloidosis, sarcoidosis)
• Hypertrophic cardiomyopathies
• Uncontrolled hypertension as defined by BP >160/100 mmHg on two measurements ≥15 minutes apart
• End Stage Renal Disease (CKD 4 or greater)
• More than moderate valvular disease (e.g. exclude patients with moderate severe or severe valvular disease)
• Significant primary pulmonary disease on home oxygen
• Known contraindication for a pacemaker implant
• Advanced co-morbidity with life expectancy \< 1 year
• Patients who are currently enrolled in a potentially confounding drug or device trial during the course of the study. Co-enrollment in concurrent trials is only allowed when documented pre-approval is obtained from the Medtronic Study Manager.
• Patient is a vulnerable adult (e.g. patient mentally incapable of giving consent).