Acute heart failure (AHF) is characterized by new onset or worsening of symptoms and/or signs of heart failure (HF) requiring urgent medical assessment and treatment.1–3 Patients presenting with AHF usually require immediate initiation or intensification of HF-directed treatment, which commonly includes intravenous (IV) diuretics, and frequently leads to unplanned hospitalization.2,4,5

Despite advances in treatment, AHF continues to carry a poor prognosis. In-hospital mortality ranges from 4 to 10%, rising to as high as 50% in cases of cardiogenic shock. After discharge, overall mortality remains high, with rates of 25–30% within the first year, particularly in the first three months, a period commonly referred to as the “vulnerable phase”.6,7

In Portugal, data from national registries of the Portuguese Directorate-General of Health indicate that in 2016, 18752 patients were hospitalized for HF, and in-hospital mortality stands at 12.4%.8 Additionally, a 2017 study involving 429 patients, reported in-hospital mortality at 7.9%, while at one-year follow-up, mortality and rehospitalization were 34.3% and 30.5%, respectively.9 Portuguese data are comparable with those from other European countries. In a study covering 1995 to 2014, Fonseca et al.10 encountered AHF in-hospital mortality of 5.5–14.0% in Portuguese studies, vs. 3.8–12.0% in studies from Europe.

Drawing on the expertise and clinical experience of a multidisciplinary panel of cardiology and internal medicine specialists, this paper presents a practical, context-specific guide to the management of AHF throughout the patient journey – from hospital admission to transition of care and outpatient follow-up – adapted to the Portuguese healthcare setting. It is meant to build upon and complement the guidelines from the European Society of Cardiology – Heart Failure Guidelines,1,11 from a more practical perspective, considering the specificities of HF care in Portugal.

Acute HF can present as a clinical deterioration in patients with a prior diagnosis of HF (i.e., acutely decompensated HF) or new onset AHF in patients without known HF (i.e., de novo HF). The clinical presentation of AHF can vary widely depending on the patient's clinical profile, comorbidities, and the underlying etiology.2,3 The evaluation of patients with AHF frequently starts in the emergency room (ER), where evidence-based strategies are limited. Therefore, the clinical approach to AHF varies widely among healthcare professionals and across centers. This section aims to establish a standardized and comprehensive approach to the initial evaluation of patients with AHF in the Portuguese ER context (Figure 1).

Figure 1.

AHF admission roadmap. AHF: acute heart failure; BNP: B-type natriuretic peptide; CBC: complete blood count; ECG: electrocardiogram; HF: heart failure; ICU: intensive care unit; LVEF: left ventricular ejection fraction; NTproBNP: N-terminal pro B-type natriuretic peptide; WHF: worsening heart failure.

The primary objective at the time of admission is to establish a diagnosis of AHF rapidly, determine the patient's clinical profile, identify any acute causes or precipitating factors, and initiate appropriate therapy without delay.

Acute heart failure can present under different clinical phenotypes, and initial management depends on the severity of congestion and the presence of hypoperfusion.23 Defining the hemodynamic profile is crucial to guiding initial treatment effectively. Oxygen therapy and non-invasive ventilation are essential measures in patients with low peripheral oxygen saturation levels and significant breathing effort.3

Management of the congestive phase in heart failure

Up to 90% of AHF patients show congestion signs at admission, and over one-third remain congestive at discharge.13 Residual congestion at hospital discharge has a clear negative prognostic impact on AHF patients; therefore, during hospitalization, from admission to discharge, all efforts are required to achieve an effective decongestion.13

Diuretic therapy: route, starting dose and monitoring

In congested patients, IV diuretics are required to achieve an effective decongestion as gastroenteric congestion compromises the absorption of oral diuretics. Intravenous furosemide offers reliable bioavailability and a predictable titration dose. Figure 2 presents a management proposal for diuretic therapy in congested patients.

Figure 2.

Diuretic therapy. *Urine output <100–150 mL/h within the first 6 hours or urinary Na concentration <50 mEq/L within 2 hours post-administration or worsening of symptoms and signs of congestion; **Same as above+progression from clinical profile B to C (hypoperfusion arising). ASAP: as soon as possible; ER: emergency room; GDMT: guideline-directed medical therapy; HF: heart failure; IV: intravenous; MRA: mineralocorticoid receptor antagonists; RRT: renal replacement therapy; SGLT2i: sodium-glucose co-transporter-2 inhibitors.

The DOSE study revealed that a high-dose of IV furosemide (2.5 times daily oral dose) provided faster and more effective decongestion than low-dose (equal to daily oral dose), but with a transient and reversible increase in serum creatinine.35 There was no difference between bolus (twice a day) and continuous administration.35,36 Nevertheless, continuous infusion may be preferred for higher doses of loop diuretic but requires a loading dose to achieve therapeutic plasma concentrations rapidly.37 As loop diuretics induce diuresis and natriuresis, a diuretic response should be assessed using urine volume and sodium (UNa) concentrations. A satisfactory diuretic response is indicated by achieving a urine output >100–150 mL/h within the first 6 hours or detecting a UNa concentration >50–70 mEq/L within 2 hours post-administration.1 If those thresholds are not met, the diuretic dose should be doubled to attain adequate decongestion.24

Overcoming diuretic resistance

Patients with chronic HF and on long-term diuretic therapy may present an impaired sensitivity to diuretics, defined as diuretic resistance.38 Diuretic resistance should be considered in the absence of an effective diuretic response to a high-dose IV loop diuretic therapy (Figure 2).

Strategies to overcome diuretic resistance include:

• 1.

  Increasing furosemide dose, by doubling it, up to 400–600 mg/day;

• 2.

  Combining furosemide with other agents targeting different nephron sites, known as “sequential nephron blockade”: In the ADVOR trial, acetazolamide, a carbonic anhydrase inhibitor that reduces proximal tubular sodium reabsorption, was found to improve decongestion rates within 72 hours in combination with furosemide.39 Hydrochlorothiazide or metolazone, targeting the distal tubule, enhance natriuresis but may increase risks of kidney dysfunction and electrolyte disturbances (hypokalemia and hyponatremia), as seen in the CLOROTIC and DEA-HF studies.40,41 Metolazone has traditionally been used as the second diuretic in Portugal since access to IV acetazolamide and isolated hydrochlorothiazide is limited.

• 3.

  Sodium-glucose cotransporter-2 inhibitors are also current options to overcome diuretic resistance. Their use in hospitalized AHF patients enables better decongestion and guideline-directed medical therapy (GDMT) optimization at the same time.42 These agents, such as empagliflozin (EMPULSE study) and dapagliflozin (DICTATE-AHF study), enhance diuresis and natriuresis with fewer adverse renal and electrolyte effects compared to thiazide diuretics.42–44

Understanding renal function in acute heart failure

Renal function evaluation during AHF hospitalization should not rely exclusively on changes in glomerular function, but also on the interpretation of the tubular response to the diuretic therapy (diuretic response/efficacy) and the capacity to eliminate residual congestion. When creatinine elevation accompanies an adequate decongestion and the introduction or titration of neurohumoral blockade, it should not be associated with a worse prognosis and should not lead to the immediate suspension of the diuretic therapy if congestion persists. This situation is referred to as “pseudo-worsening kidney function”.45,46 On the other hand, extreme variations in creatinine should alert physicians to the development of “true-worsening kidney function”, especially when accompanied by other metabolic disturbances like hyperkalemia or metabolic acidosis.46 In hemodynamically stable patients, strategies such as ‘sequential nephron blockade’ or even ultrafiltration, should be considered, whereas in hemodynamically unstable patients, admission to intensive care units for inotropic, vasopressor, or mechanical circulatory support may be warranted.46

Transition from intravenous diuretics to oral diuretics

The decision to switch from IV to oral diuretics should be guided by evidence of effective decongestion. During hospitalization, clinical improvement, NT-proBNP reduction >30%, and regression of pulmonary B-lines on POCUS correlate with adequate decongestion and should be integrated to avoid subclinical congestion.27,46 Gradual tapering of IV diuretics and ensuring clinical stability upon transition to oral diuretics during 24–48 hours before discharge are recommended.46

During the stable phase, the goals are to confirm or reassess HF etiology, control comorbidities, and start or optimize evidence-based disease-modifying therapy.1

Therapeutic management in the stable phase

In-hospital care provides a unique opportunity to change the natural history of the disease. This critical period is ideal for optimizing treatment by initiating, adjusting, or titrating prognosis-modifying therapies, thereby reducing the risk of hospital readmission. In HFrEF, GDMT should be gradually uptitrated as tolerated, aiming to implement all four pillars of GDMT. Based on the result from STRONG-HF,54,55 in hemodynamically stable hospitalized AHF patients who respond well to diuretics, early initiation, rapid dose escalation of oral HF therapies, and close follow-up within the first six weeks after discharge is recommended to reduce HF readmissions or all-cause mortality.1 Stability is generally defined as having an SBP of at least 100 mmHg, no use of IV inotropic therapy in the prior 24 hours, and no escalation in IV diuretics or vasodilators within the past six hours.56 Care should be taken to avoid intravascular volume depletion, as this can lead to hypotension and intolerance to renin-angiotensin system antagonists. Angiotensin receptor–neprilysin inhibitors (ARNi) should replace angiotensin converting enzyme inhibitors or angiotensin receptor blockers (ARB).

The TRANSITION study confirmed the safety of initiating sacubitril/valsartan during hospitalization, even for newly diagnosed patients.57 While the PIONEER study showed that early ARNi initiation reduces NT-proBNP and may further lower readmissions.58

Follow-up should prioritize assessing symptoms and signs of congestion, blood pressure, heart rate, NT-proBNP levels, potassium and estimated glomerular filtration rate. For patients with lower blood pressure, starting with a low dose of an ARB may be appropriate, with a potential transition to sacubitril/valsartan before discharge if a low dose of beta-blocker is tolerated (e.g., bisoprolol 1.25 mg once daily or carvedilol 3.125 mg twice daily).56 In cases of mild renal function decline or asymptomatic blood pressure reductions during HF hospitalization, GDMT discontinuation should not be routinely warranted.

In patients with established HFrEF, if discontinuation of GDMT becomes necessary during hospitalization, it should be restarted promptly as soon as the patient is clinically stable. Multiple studies have highlighted the detrimental effects of interrupting these therapies.59,60 Key aspects of medical therapy in the HFrEF stable phase are presented in Figure 3.

Figure 3.

Key aspects of medical therapy in the stable phase. ACEi: angiotensin converting enzyme inhibitors; ARB: angiotensin receptor blockers; ARNi: angiotensin receptor–neprilysin inhibitors; b.i.d.: twice a day; HFrEF: heart failure with reduced ejection fraction; MRA: mineralocorticoid receptor antagonists; o.d.: once a day; Sac/Val: sacubitril/valsartan; SGLT2i: sodium-glucose co-transporter-2 inhibitors; t.i.d.: three times a day.

Although STRONG-HF included patients with HmrEF and HFpEF, evidence supporting use of the four pillars of GDMT in those patients is limited. SGT2 inhibitors have a class I indication irrespective of LVEF class and should, accordingly, be initiated in all HF patients, including in AHF setting.11,42 The other three therapeutic classes may be considered in HFmrEF.1,11 In HF with LVEF>=40%, recent evidence from FINEARTS-HF trial showed that finerenone reduced the composite outcome of CV death and HF events, including in patients who have experienced a recent worsening HF event.61

Patients discharged after an AHF episode have high rates of readmission and mortality in the first 2–3 months after hospitalization.62 Although these numbers are not well documented in Portugal, it is estimated that around 25% of patients are readmitted within 30 days and 50% in six months following discharge after an AHF episode.63 Accordingly, interventions targeting this transition period have high potential to impact prognosis and healthcare costs.

Many transition care programs have been developed for AHF patients, with heterogeneous designs, methods and endpoints, leading to inconsistent results. HF management is complex and roadblocks at the patient, doctors, family, hospital, and primary care levels can be encountered.62,64 We believe that the most successful strategies are those tailored to the local context and available resources. The specific characteristics of the Portuguese healthcare system should be taken into account when improving the transition of care among HF patients in Portugal.

Most transition programs (generally coordinated by a HF nurse) include eight common features: patient education, early assessment after admission, medication reconciliation, inclusion of caregivers, telephone follow-up, early follow-up after discharge, home visits, and handoff to post-hospital providers.62 These features can be adapted to the Portuguese context; however, we believe that in-hospital multidisciplinary team discussion, planning and treatment optimization should also be added to the program. As an integrated transition program for implementation in Portugal, we recommend:

• 1.

  Admission period:

  • •

    Early assessment after hospital admission – Transition planning should start at the beginning of hospital admission. An early assessment, usually performed by an HF nurse integrated into an HF team, should include patient and family HF literacy and identify gaps to be corrected before discharge. It also helps with planning home-care services and identifying equipment requirements (e.g., hospital beds, walking aids, home adaptations) needed after discharge, as well as social and/or financial support. This should be done in close collaboration with the social work team, as Portuguese HF patients are often older and socioeconomically disadvantaged.65 Involving key caregivers and family is crucial to optimize HF literacy, treatment adherence, psychosocial support, and monitor early signs of disease decompensation.

  • •

    In-hospital multidisciplinary assessment: any hospitalized AHF patient's case should be discussed by a HF multidisciplinary team to identify the main issues in each patient, including a full profiling of the HF and comorbidities, identification and management of AHF precipitants and definition of tailored management strategies both during hospitalization and post-discharge.

  • •

    Treatment optimization: HF treatments should be optimized according to individual patient tolerability, with every effort made to ensure the implementation of prognosis-modifying therapies, as this strategy improves outcomes following an AHF admission.54 Comorbidities should be addressed (section 4.3/Table 5). Indication and referral for advanced HF treatments and palliative care or other therapeutic/diagnostic interventions should be considered. All these domains should be discussed by the HF team and the patients/caregivers while they are still in the hospital and should be clearly written in the discharge letter addressed to the patients, their families and their primary care doctor.

• 2.

  Pre-discharge:

  • •

    Patient education: HF nurses should educate patients when stable before discharge, regarding diet and exercise, HF signs and symptoms monitoring, self-care expectations and strategies, medication education and counselling. This training should address both patients and caregivers. Support materials can be provided.

  • •

    Medication reconciliation: Redundant and non-evidence-based treatments should be eliminated to simplify treatment regimens while maintaining essential medicines. Treatment adherence is a primary goal and HF nurses and dedicated hospital pharmacists play a crucial role in this step.

  • •

    Checklist: It is of utmost importance for hospital discharge to take place whenever the patient's condition has been optimized and a safe transition is anticipated. A pre-discharge checklist, such as the one previously developed by the Núcleo de Estudos em Insuficiência Cardíaca (Supplementary Table S2),66 is useful to verify that the most relevant HF issues, comorbidities and organizational matters have been satisfactorily addressed during hospitalization, confirming discharge readiness. Patients in whom any of the identified issues could not be managed should be flagged for a closer follow-up.

  • •

    Handoff to post-hospital providers: To facilitate multidisciplinary care, a printed discharge summary of the hospitalization is recommended as the official handoff tool. Primary care physicians should have an easy, simple way to communicate with the HF team (e.g., a dedicated phone number written in the handoff letter). Ideally, an alert system could notify primary care doctors whenever their patients are hospitalized/discharged, to facilitate appropriate interactions between hospital and primary care teams, favoring integrated care.

• 3.

  Early post-discharge period

  • •

    Telephone follow-up: To provide education and support, manage symptoms, and recognize complications early after hospitalization, HF nurses can use post-discharge follow-up telephone calls. We suggest a phone call within one week after discharge, tailoring the frequency of subsequent contact with patient preferences and needs. The identification of patients at high-risk of readmission could support this tailored follow-up planning (Figure 4). A case management strategy could be helpful for chronic complex HF patients, which is already in place at a few Portuguese centers; chronic complex patient units should liaise regarding care with the HF team.

    
    

    Figure 4.

    Transition program for acute heart failure patients. #High-risk patients: patients with ≥1 hospital admission or emergency department visit within 3 months, ≥75 years, with comorbidities (chronic kidney disease [sustained estimated glomerular filtration rate <60 mL/min/1.73 m2 and/or urinary albumin-to-creatinine ratio ≥30 mg/g], chronic obstructive pulmonary disease, cerebrovascular disease, dementia, depression, diabetes or cancer), deficient socio-economic support, high pre-discharge NT-proBNP levels (>1000 pg/mL) and low systolic blood pressure (<100 mmHg) have higher risk for adverse outcomes following an AHF admission. HF: heart failure.
  • •

    Early follow-up visits after discharge: We suggest at least one medical visit within one to four weeks after hospital discharge, preferably in-person but it can be performed remotely based on patient preferences/limitations. The day hospital is an adequate setting for this re-evaluation. The primary care physician could also carry out this visit. Clinical re-evaluation and medical therapy up-titration are crucial steps in this visit, which should also include other important actions to optimize patient management. In Supplementary Table S3, we propose a checklist for this early post-discharge appointment.

  • •

    Home visits: This intervention is not ‘mandatory’ but should be implemented whenever possible (by a HF nurse) within the early phase after hospital discharge (one to two months) to reinforce education and help patients in their self-care decisions.

  • •

    Telemonitoring: In some cases, a remote monitoring approach could be useful. This is already in place at some Portuguese centers and is usually reserved for patients at higher risk of adverse outcomes.

  • •

    Cardiac rehabilitation: Although not currently available at many Portuguese centers, the integration of a supervised, exercise-based, cardiac rehabilitation program should be considered in patients with more severe disease, frailty, or with comorbidities.1 These rehabilitation programs can be performed in a ‘home-based’ context for patients who live far away from the tertiary center or cannot attend frequent hospital appointments. A detailed implementation of a ‘home-based’ HF rehabilitation strategy in Portugal has been previously reported.67

In short, we believe these steps can be implemented for the transition of care at most tertiary care facilities in Portugal. HF nurses play a vital role in these multidisciplinary programs. We are aware that most centers in Portugal do not have specialized HF nurses; however, institutions should try to identify motivated personnel to set up an HF team with the main goal of managing patients following best practice standards. Ideally, these HF teams should have a minimum of two nurses, two internal medicine specialists, and one cardiologist. These are the minimum human resources expected in centers classified as level 2 under the 2023 National Hospital Referral Network Proposal,68 or as community centers according to the European Society of Cardiology's Quality of Care Centre classification.69 The effectiveness of transition programs should be monitored.

Acute heart failure poses significant clinical and economic challenges that require a comprehensive, evidence-based approach extending from in-hospital management to post-discharge care.

This practical guide highlights the importance of optimizing GDMT by tailoring and rapidly up-titrating treatments as needed to reduce mortality and readmissions. The implementation of structured, multidisciplinary transition programs that ensure the continuity of care is equally essential. These programs should incorporate early in-hospital assessments, the use of pre-discharge checklists (e.g., from the NEIC), and robust patient education initiatives led by specialized HF nurses.

Effective AHF management also requires addressing comorbidities, simplifying medication regimens, and engaging both patients and caregivers in self-care strategies. While we acknowledge the constraints faced by many Portuguese centers, this guide advocates for the proactive formation of dedicated HF teams to support best practice standards. Through the adoption of these integrated, patient-focused strategies in local healthcare settings, patient clinical outcomes can be enhanced, the burden of hospital readmissions can be reduced, and the quality of life of patients affected by AHF can be improved.

Ana Santos from Prime Focus provided medical writing support, which was supported by Boehringer Ingelheim and Novartis. Boehringer Ingelheim and Novartis had no role in the design, analysis or interpretation of the results in this study. Boehringer Ingelheim was given the opportunity to review the manuscript for medical and scientific accuracy as it relates to Boehringer Ingelheim substances, as well as intellectual property considerations.

Joana Pimenta has received speaker/consultant fees from AstraZeneca, Bayer, Bial, Boehringer Ingelheim/Lilly, Daiichi-Sankyo, GSK, Novartis, Pfizer, Servier and Vifor Pharma.

João Pedro Ferreira has no conflicts of interest to declare.

Francisco Vasques-Nóvoa has received consulting or speaker fees from Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Daiichi Sankyo, Novartis and Ultragenyx.

David Roque has received speaker fees from Bial, AstraZeneca, Novartis, Servier, Boehringer Ingelheim and Orion Pharma.

Inês Araújo has received speaker fees from AstraZeneca, Bayer, Bial, Novartis, Servier, and Advisory fees from AstraZeneca, Bayer, Novartis and Boehringer Ingelheim/Lilly.

César Lourenço has no conflicts of interest to declare.

Susana Dias da Costa has received speaker fees from Boehringer Ingelheim and Novartis Portugal but not related to this paper.

Sara Gonçalves has received speaker fees from AstraZeneca.

Ana Neto has received speaker fees from Novartis, Bial and Daiichi Sankyo.

Filipa Almeida has no conflicts of interest to declare.

Pedro Moraes Sarmento has received consultant or speaking fees from AstraZeneca, Bayer, Boehringer Ingelheim, Lilly and Pfizer.

João Agostinho has received consultant and speaking fees from AstraZeneca, Bayer, Bial, Boehringer Ingelheim & Lilly, Alnylam, Novartis, Daiichi Sankyo and Pfizer.

Irene Marques has received speaker and consultant fees from AstraZeneca, Bayer, Bial, CSL Vifor, Daiichi-Sankyo, Lilly, Novartis, Novo Nordisk, Pfizer, Roche Diagnostics and Servier.

Elisabete Martins has received speaker and consultant fees from AstraZeneca, Bial, Amicus Therapeutics, Sanofi, Amgen and Pfizer.