This Study Tests Empagliflozin in Patients With Chronic Heart Failure With Preserved Ejection Fraction (HFpEF). The Study Looks at How Far Patients Can Walk in 6 Minutes and at Their Heart Failure Symptoms.

The primary objective of the study is to evaluate the effect of empagliflozin 10 mg versus placebo on exercise ability using the 6 minute walk test (6MWT) in patients with chronic heart failure (CHF) with preserved ejection fraction (LVEF \> 40%).

Secondary objectives are to assess Patient-Reported Outcome (PRO)


Eligibility Criteria:
Inclusion Criteria:

* Of full age of consent (according to local legislation, usually ≥ 18 years) at screening.
* Male or female patients. Women of child bearing potential (WOCBP) must be ready and able to use highly effective methods of birth control per ICH M3 (R2) that result in a low failure rate of less than 1% per year when used consistently and correctly. A list of contraception methods meeting these criteria is provided in the patient information.
* Signed and dated written informed consent in accordance with ICHGCP and local legislation prior to admission to the trial
* Six minute walk test (6MWT) distance ≤350 m at screening and at baseline.
* Patients with CHF diagnosed for at least 3 months before Visit 1, and currently in NYHA class II-IV
* Chronic heart failure (CHF) with preserved Ejection fraction (EF) defined as left ventricle ejection fraction(LVEF) \> 40 % as per echocardiography at Visit 1 per local reading and no prior measurement of LVEF ≤ 40% under stable conditions.
* Elevated N-Terminal Pro-Brain Natriuretic Peptide (NT-proBNP) \> 300 pg/ml for patients without atrial fibrillation (AF), OR \> 600 pg/ml for patients with AF, as analysed at the Central laboratory at Visit 1
* Patients must have at least one of the following evidence of heart failure (HF):

  * Structural heart disease (left atrial enlargement and/or left ventricular hypertrophy) documented by echocardiogram at Visit 1, OR
  * Documented Hospitalization for Heart Failure (HHF) within 12 months prior to Visit 1
* Consistent with prevailing CV guidelines, if oral diuretics are prescribed to control symptoms, patients must be on an appropriate and stable dose of oral diuretics for at least 2 weeks prior to Visit 1 to control symptoms.
* Clinically stable at randomization with no signs of heart failure decompensation (as per investigator judgement).

Exclusion Criteria:

* Myocardial infarction (increase in cardiac enzymes in combination with symptoms of ischaemia or newly developed ischaemic ECG changes), coronary artery bypass graft surgery or other major cardiovascular surgery, stroke or transient ischemic attack in past 90 days prior to Visit 1
* Acute decompensated HF (exacerbation of CHF) requiring intravenous (i.v.) diuretics, i.v. inotropes or i.v. vasodilators, or left ventricular assist device within 4 weeks prior to Visit 1, and/or during screening period until Visit 2
* Previous or current randomisation in another Empagliflozin Heart Failure trial (i.e. studies 1245.110, 1245.121, 1245-0168)
* Type 1 Diabetes Mellitus (T1DM)
* Impaired renal function, defined as eGFR \< 20 mL/min/1.73 m2 (CKD-EPIcr) or requiring dialysis, as determined at Visit 1
* Symptomatic hypotension or a systolic blood pressure (SBP) \< 100 mmHg at Visit 1 or 2
* SBP ≥ 180 mmHg at Visit 1 or 2, or SBP \>160mmHg at both Visit 1 and 2
* Atrial fibrillation or atrial flutter with a resting heart rate \> 110 bpm documented by ECG at Visit 1 (Screening)
* Unstable angina pectoris in past 30 days prior to Visit 1
* Largest distance walked in 6 minutes (6MWTD) at baseline \<100m.
* Any presence of condition that precludes exercise testing such as:

  * claudication,
  * uncontrolled (according to investigator judgement) bradyarrhythmia or tachyarrhythmia,
  * significant musculoskeletal disease,
  * primary pulmonary hypertension,
  * severe obesity (body mass index ≥40.0 kg/m2),
  * orthopedic conditions that limit the ability to walk (such as arthritis in the leg, knee or hip injuries)
  * amputation with artificial limb without stable prosthesis function for the past 3 months
  * Any condition that in the opinion of the investigator would contraindicate the assessment of 6MWT
* Patients in a structured (according to Investigator judgement) exercise training program in the 1 month prior to screening or planned to start one during the course of this trial.
* ICD implantation within 1 month prior to Visit 1 or planned during the course of the trial
* Implanted cardiac resynchronisation therapy (CRT)
* Treatment with i.v. iron therapy or erythropoietin (EPO) within 3 months prior to screening.
* Further exclusion criteria applies