NOVEL-HF is a multicenter, observational nationwide registry of HFimpEF and HFsnEF conducted in cooperation with the Scientific Platform of the Polish Society of Cardiology.

According to the current definitions the criteria for HFimpEF diagnosis include patients with HF with an initial left ventricular ejection fraction (LVEF) below 40%, with at least a 10% increase during follow-up, and with final values >40%. HFsnEF includes patients with HF whose LVEF values on echocardiography are >65%.

The patient data will be collected from standardized and anonymous forms via the Scientific Platform of the Polish Society of Cardiology. The NOVEL-HF registry will involve the complete clinical, laboratory, and echocardiographic characteristics, as well as introduced pharmacological treatment. The occurrence of end-points (all-cause mortality, cardiovascular mortality, HF decompensations, worsening of HF symptoms) will be assessed in short- and long-term follow-up.

In accordance with initial assumptions, 500 HFimpEF and 200 HFsnEF patients in all participating centers will be included.

Ethical approval was granted by the local Bioethics Committee.

Heart failure with improved ejection fraction (HFimpEF) and heart failure with supranormal ejection fraction (HFsnEF) are new and poorly understood subtypes of heart failure with significant prognostic implications.

The primary goal of the proposed "Nationwide registry of patients with heart failure with improved and supranormal ejection fraction (NOVEL-HF)" is to comprehensively characterize the Polish population of patients with HFimpEF and HFsnEF.

The collected data will allow for understanding their etiology, determining detailed clinical characteristics, and predictors of mortality in both short and long-term follow-up. Once a sufficient number of patients are enrolled, new prognostic scoring scales will be developed based on NOVEL-HF registry data to aid in predicting prognosis in these patient groups.

Each participating center will enroll patients > 18 years old retrospectively from their internal databases based on the clinical and echocardiographic diagnosis of HFimpEF and HFsnEF, but also prospectively for six months from the NOVEL-HF joining with informed consent of the patients.

NOVEL-HF is a multicenter, observational nationwide registry of HFimpEF and HFsnEF conducted in cooperation with the Scientific Platform of the Polish Society of Cardiology.

According to the current definitions the criteria for HFimpEF diagnosis include patients with HF with an initial left ventricular ejection fraction (LVEF) below 40%, with at least a 10% increase during follow-up, and with final values >40% [1]. HFsnEF includes patients with HF whose LVEF values on echocardiography are >65%.

The patient data will be collected from standardized and anonymous forms via the Scientific Platform of the Polish Society of Cardiology. The NOVEL-HF registry will involve the complete clinical, laboratory, and echocardiographic characteristics, as well as introduced pharmacological treatment. The occurrence of end-points (all-cause mortality, cardiovascular mortality, HF decompensations, worsening of HF symptoms) will be assessed in short- and long-term follow-up.

In accordance with initial assumptions, 500 HFimpEF and 200 HFsnEF patients in all participating centers will be included.

Ethical approval was granted by the local Bioethics Committee.

Data obtained from the NOVEL-HF registry will enable understanding the HFimpEF and HFsnEF etiology, determining detailed clinical characteristics, and predictors of mortality in both short and long-term follow-up. Once a sufficient number of patients are enrolled, new prognostic scoring scales will be developed based on NOVEL-HF registry data to aid in predicting prognosis in these patient groups.

It was planned to prepare at least 5 full-text publications in peer-reviewed Polish (Polish Heart Journal) and foreign journals.

The condition for participation in NOVEL-HF and the planned publications is the inclusion of at least 50 patients with HFimpEF and/or 20 patients with HFsnEF.

Inclusion Criteria:

• HFimpEF or HFsnEF diagnosis

Exclusion Criteria:

• None

Each participating center will enroll patients > 18 years old retrospectively from their internal databases based on the clinical and echocardiographic diagnosis of HFimpEF and HFsnEF, but also prospectively for six months from the NOVEL-HF joining with informed consent of the patients.