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The HF-POL study — the first real-life multicenter study of Polish patients with heart failure and left ventricular ejection fraction >40%: Study rationale and design

Małgorzata Lelonek1Mariusz Gąsior2Marcin Grabowski3
1Department of Noninvasive Cardiology, Medical University of Lodz, Łódź, Poland
23rd Department of Cardiology, Silesian Centre for Heart Diseases in Zabrze, Medical University of Silesia, Faculty of Medicine, Zabrze, Poland
31stDepartment of Cardiology, Medical University of Warsaw, Warszawa, Poland

Correspondence to:

Prof. Małgorzata Lelonek, MD, PhD, FESC, FHFA,

Department of Noninvasive Cardiology,

Medical University of Lodz,

Żeromskiego 113, 90–549 Łódź, Poland

phone: +48 42 639 37 93,


Copyright by the Author(s), 2022

DOI: 10.33963/KP.a2022.0237

Received: September 5, 2022

Accepted: October 10, 2022

Early publication date: October 25, 2022


According to the new classification of heart failure (HF) presented in the 2021 guidelines of the European Society of Cardiology (ESC), HF with left ventricular ejection fraction (LVEF) higher than 40% covers 3 distinct phenotypes: HF with mildly reduced LVEF (41%–49%), HF with preserved LVEF (>50%), and HF with improved LVEF [1].

Data from the National Health Fund revealed that in in 2020 there were more than 740 000 patients with HF in Poland, about half of whom had LVEF >40% [2]. Considering the statistics and increasing healthcare costs, HF constitutes a significant clinical and economic burden in Poland. Hospitalizations are the key cost category in the HF setting. Despite advances in HF diagnosis and treatment, the rates of costly and at least partially preventable hospitalizations remain high in Poland. According to the 2019 report of the Organization for Economic Co-operation and Development (OECD), Poland had the highest HF-related hospitalization rates in 2018 among OECD members, and these rates are more than twice as high as the OECD average [3]. Moreover, in 2020, the number of HF-related deaths accounted for 26% of all deaths in Poland (123 316/477 355, respectively) [2].

In Poland, HF is the most common direct cause of death. Numerous international studies showed that HF with LVEF >40% is associated with a serious prognosis [4–6]. In contrast to HF with reduced LVEF, treatment aimed at improving prognosis in patients with LVEF >40% has a lower class of recommendation (up to IIa), based largely on weaker evidence and/or expert opinions in the 2021 ESC (class IIb) and 2022 ACC/ACC/HFSA (class IIa) guidelines [1, 7, 8]. However, the results of the recently published trials (EMPEROR-Preserved and DELIVER) call for review of this HF population [9, 10].

The population of Polish patients with HF and LVEF >40% has not been well described so far. This is partly due to limitations in the International Classification of Disease coding, which does not reflect the classification of HF based on LVEF values. This is an important barrier to determining the actual percentage of HF patients with LVEF >40% in Poland. We still need reliable data on HF. Therefore, to assess this population in Poland, the Heart Failure Association of the Polish Cardiac Society designed a multicenter observational study as part of the Society’s Scientific Platform initiative. The study aims to collect data on Polish patients with HF and LVEF >40% and to provide a better understanding of medical practice, based on observational data, including diagnosis, treatment, and prognosis over 1-year follow-up. The study will be a valuable source of clinical practice data and will provide useful information that will guide decisions and policies to improve the management and prognosis of patients with HF, as well as prevent hospitalizations in Poland.


The Heart Failure Poland (HF-POL) study is a multicenter observational study including patients with HF and LVEF >40%, conducted by the Heart Failure Association of the Polish Cardiac Society in cooperation with the Committee for Clinical Initiatives of the Executive Board as part of the Scientific Platform initiative. The leading center of the study is the Military Medical Academy Memorial Teaching Hospital of the Medical University of Lodz, Poland. The Primary Investigator is Malgorzata Lelonek; the Steering Committee includes Malgorzata Lelonek, Mariusz Gasior, and Marcin Grabowski.

Patients have been recruited at each participating center since that center’s activation on the platform (a clinical data management system, All consecutive patients meeting the inclusion and exclusion criteria are being enrolled. Patients are diagnosed and treated according to the current clinical practice guidelines and the standard of care at participating centers. Indications for diagnostic procedures and therapeutic interventions are assessed by the physicians at participating centers.

A phone interview with the patient or his or her family is scheduled 1 year after enrollment to the study, and the following data will be collected: general medical condition, HF-related or all-cause hospitalization, and death.

The study was approved by the Bioethics Committee at the Medical University of Lodz (No. RNN/240/21/KE; October 21, 2021). The study execution is regulated by the Rules and Regulations of the Scientific Platform of the Polish Cardiac Society and an agreement between the Polish Cardiac Society, participating centers, and Primary Investigator.

The study population includes patients with HF and LVEF >40%. In total, a minimum of 1000 patients from 14 Polish centers (Supplementary material, Table S1) will be enrolled. The study will include consecutive patients with the ICD codes I50 (I50.0, I50.1, I50.9) and J81, who fulfill the following inclusion criteria: have recognized HF with documented LVEF >40% and are either treated for HF on ambulatory basis or hospitalized for HF (HF exacerbation or HF de novo) with administration of intravenous therapy (diuretics and/or catecholamines). HF should be recognized according to the 2021 ESC guidelines [1]. The study allows recruitment based on results from medical records, especially for outpatients with a history of HF. However, not all patients had their results documented within 12 months before screening. In the case of HF de novo, the 2021 ESC guidelines criteria for this diagnosis should be applied as symptoms and/or signs, LVEF >40%, and for heart failure with preserved ejection fraction (HFpEF), objective evidence of cardiac structural and/or functional abnormalities consistent with the presence of left ventricular diastolic dysfunction/raised left ventricle filling pressure, including raised natriuretic peptides [1]. The exclusion criteria are age <18 years and dyspnea due to causes other than HF. The flowchart presents the study design (Figure 1).

Figure 1. Study flowchart
Abbreviations: ESC, European Society of Cardiology; HF, heart failure; LVEF, left ventricular ejection fraction

Because of the COVID-19 pandemic, patients have been recruited retrospectively over 3 months before the activation of the centers on the platform and prospectively over 4 months. The total duration of recruitment will be 7 months. The study started in January 2022.

Statistical analysis

Normally distributed continuous variables were reported as mean (SD) values. Not normally distributed continuous variables and ordinal variables were presented as median values and interquartile ranges (IQR). Categorical data were reported as the number and percentage of patients. The statistics were calculated with STATISTICA 13 software (TIBCO Software, Palo Alto, CA, US).

Preliminary Results and Discussion

Until May 26, 2022, a total of 790 patients were recruited to the study (mean age, 72.9 [11.2] years; range 31106 years; 51% male). More than half of patients have an ischemic etiology of HF (57%). The following cardiovascular risk factors and comorbidities were reported: hypertension (87%), diabetes (73%), hyperlipidemia (67%), atrial fibrillation (58%), chronic obstructive pulmonary disease (12%), and cancer (11%). COVID-19 was reported in 18% of the studied population.

In most patients, a history of hospitalization in the previous 12 months was reported (80%) while 53% of patients were enrolled in the study during HF hospitalization. Most patients were in New York Heart Association functional class II and III (332 and 311 patients, respectively). The mean blood pressure was reported at 132/77 (19.85/12.56) mmHg; body mass index, 29.6 (6.2) kg/m2; LVEF of 52.7 (7.5) %, median N-terminal pro-B-type natriuretic peptide level of 1 177 (430-12 798) pg/ml; estimated glomerular filtration rate, 62 (24.79) ml/min/1.73 m2; and six-minute walk distance, 287.5 (105-310) m. At baseline, 72% of the studied patients were on angiotensin-II converting enzyme inhibitor/angiotensin-II receptor blocker (ACEI/ARB), 67% had loop diuretics, 79% beta-blockers, 61% mineralocorticoid receptor antagonists (MRA), 71% statins, and 12% flozins.

Our preliminary results are consistent with the literature and other registries apart from the higher concentration of NT-proBNP, higher frequency of HF hospitalization, diabetes, MRA therapy, and male sex.


The presented study has limitations typical of such projects. These are limited information on clinical characteristics, treatment, and adverse events. The participating centers have been selected, and the majority of them represent university centers with involved teams of experienced cardiologists, which may not reflect clinical practice of regional and local reference centers. For technical and budgetary reasons, opportunities for verifying the entered data, monitoring and detailed follow-up are also restricted. On the other hand, cardiovascular registries play an integral role in providing real-world data. An additional limitation is the retrospective-prospective design of the study, which was caused by the pandemic. Moreover, not all outpatients had their laboratory and echocardiographic results, which was also caused by the pandemic.


The HF-POL study is the first real-life national multicenter observational study including patients with HF and LVEF >40%, conducted by the Heart Failure Association of the Polish Cardiac Society. The population of patients with HF and LVEF >40% has been growing and constitutes an increasing health burden. Considering the statistical, economic, and epidemiological real-life data for Poland, it is necessary to identify prognostic factors that could help improve the management of these patients by reducing the risk of hospitalizations and death.

Supplementary material

Supplementary material is available at

Article information

Conflict of interest: None declared.

Funding: None.

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  1. McDonagh TA, Metra M, Adamo M, et al. 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J. 2021; 42(36): 35993726, doi: 10.1093/eurheartj/ehab368, indexed in Pubmed: 34447992.
  2. Maps of Heath Needs. System and Impementation Analysis Database Platform. Epidemiology. Available online: Accessed: November 27, 2022.
  3. Organization for Economic Co-operation and Development. 2019. Health at a glance 2019. OECD Publishing: Paris, France.
  4. Savarese G, Stolfo D, Sinagra G, et al. Heart failure with mid-range or mildly reduced ejection fraction. Nat Rev Cardiol. 2022; 19(2): 100116, doi: 10.1038/s41569-021-00605-5, indexed in Pubmed: 34489589.
  5. Lelonek M. Heart failure with preserved ejection fraction after the PARAGON-HF trial results: current knowledge and future directions. Kardiol Pol. 2020; 78(12): 11991205, doi: 10.33963/KP.15639, indexed in Pubmed: 33021355.
  6. Correale M, Paolillo S, Mercurio V, et al. Non-cardiovascular comorbidities in heart failure patients and their impact on prognosis. Kardiol Pol. 2021; 79(5): 493502, doi: 10.33963/KP.15934, indexed in Pubmed: 34125921.
  7. Heidenreich PA, Bozkurt B, Aguilar D, et al. 2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. J Am Coll Cardiol. 2022; 79(17): e263e421, doi: 10.1016/j.jacc.2021.12.012, indexed in Pubmed: 35379503.
  8. Lelonek M, Grabowski M, Kasprzak JD, et al. An expert opinion of the Heart Failure Association of the Polish Cardiac Society on the 2021 European Society of Cardiology guidelines for the diagnosis and treatment of acute and chronic heart failure: Heart failure guidelines from a national perspective. Kardiol Pol. 2022; 80(2): 239246, doi: 10.33963/KP.a2022.0021, indexed in Pubmed: 35076082.
  9. Butler J, Filippatos G, Siddiqi TJ, et al. Evaluation of the effects of sodium-glucose co-transporter 2 inhibition with empagliflozin on morbidity and mortality in patients with chronic heart failure and a preserved ejection fraction: rationale for and design of the EMPEROR-Preserved Trial. Eur J Heart Fail. 2019; 21(10): 12791287, doi: 10.1002/ejhf.1596, indexed in Pubmed: 31523904.
  10. Solomon S, McMurray J, Claggett B, et al. Dapagliflozin in heart failure with mildly reduced or preserved ejection fraction. N Engl J Med. 2022; 387(12): 10891098, doi: 10.1056/nejmoa2206286, indexed in Pubmed: 36027570.


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