To the editor

We read with great interest the paper by Doryńska et al¹ published recently in Polish Archives of Internal Medicine. The study quantifies what many of us have been observing at the bedside for years: the hospitalized heart failure (HF) population is becoming older, more complex, and increasingly often presenting with phenotypes other than HF with reduced ejection fraction (HFrEF). Across admission tertiles, the rate of HFrEF fell from 74% to 53.9%, while the rates of HF with preserved (HFpEF) and mildly reduced EF (HFmrEF) rose from 16.3% to 31.3% and from 9.7% to 14.8%, respectively. At the same time, mean patient age increased (from 59.7 to 64.8 y; with the rate of individuals aged ≥65 y increasing from 27% to 52.2%), and multimorbidity intensified (median number of comorbidities rose from 4 to 5, with an increase in prevalence from 68.2% to 81.4% for hypertension, from 53.9% to 59.7% for atrial fibrillation, and from 16.4% to 33.5% for cancer). The survival signal is also striking. Five‑year survival improved from 48.4% to 60.2%, and 5‑year mortality declined from 51.6% to 39.8%, with the greatest gains confined to HFrEF.¹

Clinically, this makes sense, because systems of care (revascularization pathways, imaging, rhythm management, device therapy, and follow‑up structures) have improved, often in ways that do not simply manifest as a new pill at discharge. This is precisely why one of the most intriguing observations in the paper deserves explicit interpretation rather than being left as a Table entry: over time, discharge use of angiotensin‑converting enzyme inhibitors (ACEIs), mineralocorticoid receptor antagonists (MRAs), and diuretics decreased (ACEIs, from 88.5% to 82.1%; MRAs, from 80.6% to 67.1%; diuretics, from 89.4% to 84.1%), while β-blocker use remained essentially stable.¹

If we interpreted these numbers as a true de‑implementation, the improvement in outcomes would be difficult to reconcile. In our view, the more plausible explanation is that the study exposes the limits of what a discharge medication snapshot can tell us about the real intensity and continuity of HF care. The period analyzed (2014–2019) largely predates widespread use of sodium‑glucose cotransporter 2 inhibitors (SGLT2is) in HF, and the authors note that none of the patients received an SGLT2i, while angiotensin receptor‑neprilysin inhibitor use was rare.¹ This single finding is highly actionable today, because current guideline frameworks have dramatically changed: the 2023 European Society of Cardiology focused update places SGLT2is as a foundation therapy across the EF spectrum to reduce HF hospitalization and cardiovascular death.² The “zero exposure” in this cohort is therefore not simply a historical context—it is a benchmark that enables contemporary centers to quantify whether guideline translation is truly occurring.

We also think the methodological realities acknowledged by the authors further support caution in linking outcome trends directly to discharge pharmacotherapy: follow‑up differs by admission tertile, EF classification depends on routine documentation rather than a standardized echocardiographic protocol, and shifting case‑mix is unavoidable in observational cohorts.¹ These are not flaws—they are inherent constraints of real‑world analyses. However, they strengthen the interpretation that improved survival in HFrEF may, at least in part, reflect modernization that is only partially captured by a discharge drug list: better acute management, earlier diagnosis, more frequent dose optimization after discharge, wider access to device therapy, and more structured follow‑up.

From a practical standpoint, the next step is to make implementation measurable and link it to outcomes that are sensitive in the near term. Contemporary postinfarction programs remind us to be realistic about early end points: the clearest and most reproducible short‑horizon signal for SGLT2is is likely HF events rather than mortality, while mechanistic studies support plausibility through natriuretic peptide level reduction and favorable remodeling markers.^3-5 With the rapid expansion of HFpEF and HFmrEF in the cohort analyzed by Doryńska et al¹ (the very groups historically prone to undertreatment), reporting eligibility, initiation, and early continuation of SGLT2is alongside with early HF rehospitalization would provide a pragmatic quality indicator that aligns with modern guidelines and day‑to‑day clinical priorities.

We believe the paper offers more than a description of changing HF phenotypes; it reveals a measurable implementation gap. The combination of a rapidly expanding HFpEF/HFmrEF proportion and an absence of SGLT2i use should prompt contemporary cohorts to be analyzed with explicit reporting of eligibility, initiation, continuation, and early HF readmissions. That would turn an important observational signal into a practical quality‑of‑care instrument, and ultimately, into better outcomes for the patients we care for every day.