Europe's cardiology establishment just wrote two weight-loss peptides into its heart failure guideline. The 2026 ESC Guidelines for the management of heart failure, published in the European Heart Journal on 28 August and presented at ESC Congress 2026 in Munich, carry a new recommendation: "Semaglutide or tirzepatide should be considered for patients with symptomatic HF, LVEF ≥45%, and BMI ≥30 kg/m²... to reduce body weight, and improve exercise capacity and QoL." Class IIa, Level B.
That is a narrower claim than the headlines suggest, and the wording is worth reading twice. The stated purpose is weight, exercise capacity and quality of life — not mortality. The threshold is LVEF ≥45%, which does not match the guideline's own new definition of preserved ejection fraction (≥50%), because the recommendation is anchored to trial enrolment criteria rather than to the taxonomy. Both details matter for anyone trying to work out what the evidence actually supports.
Research-context information only. Semaglutide and tirzepatide are active ingredients in FDA-approved prescription products, prescribed and monitored by licensed clinicians. The research-peptide and compounded forms discussed and linked below are not FDA-approved, are sold for research purposes only, and are not the products these guidelines refer to. Neither compound is FDA-approved for heart failure. Retatrutide is investigational and unapproved worldwide. Guideline recommendations are written for physicians treating diagnosed patients under supervision; they are not instructions for self-administration. Protocols and doses reported here come from published clinical trials. This article reports what has been documented, not what should be done. Consult a licensed physician for personal medical decisions.
What the guideline changed
The document is a full rewrite rather than a focused update, chaired by Lars Køber (Rigshospitalet, Copenhagen) and Marianna Adamo (University and Civil Hospital of Brescia), with the Heart Failure Association contributing and EACTS endorsing.
| Change | 2021 guideline | 2026 guideline |
|---|---|---|
| Phenotypes | Three (HFrEF, HFmrEF, HFpEF) | Two — HFrEF (LVEF <50%), HFpEF (LVEF ≥50%) |
| Mildly reduced EF (41–49%) | Own category | Folded into HFrEF |
| Acute presentation | "Acute heart failure" | "Decompensated heart failure" |
| Staging | Not stage-based | Four-stage A–D framework |
| Therapy grouping | Drug-class lists | Foundational, additional, and guideline-directed interventional therapy |
| MRAs | LVEF-dependent | Class I in chronic HF independent of LVEF |
| Semaglutide / tirzepatide | Absent | Class IIa (LVEF ≥45%, BMI ≥30) |
| GLP-1 RA in T2DM | Absent | Class IIa Level A to reduce HF or CV death risk |
The elimination of the mildly-reduced category is the structural headline — the task force's stated rationale is that those patients share pathophysiology and treatment response with reduced-EF patients. But the incretin recommendation is the one that moves a compound class most peptide buyers already know from the weight-loss column into the cardiology column.
The two trials underneath the recommendation
Class IIa Level B means two things: the balance of evidence favours the intervention, and that evidence comes from a limited number of randomised trials. In this case, two programmes.
SUMMIT — tirzepatide. 731 patients with heart failure, ejection fraction ≥50%, and BMI ≥30, randomised 1:1 to tirzepatide up to 15 mg weekly or placebo, median follow-up 104 weeks. Cardiovascular death or a worsening heart-failure event: 36 patients (9.9%) on tirzepatide versus 56 (15.3%) on placebo, hazard ratio 0.62 (95% CI 0.41–0.95, P = 0.026). KCCQ clinical summary score improved 19.5 points versus 12.7, a between-group difference of 6.9 points (PMID 39555826).
The composite was carried almost entirely by the worsening-HF component (HR 0.54, 95% CI 0.34–0.85). Cardiovascular deaths went the other way — 8 on tirzepatide, 5 on placebo, HR 1.58 with a confidence interval running from 0.52 to 4.83. That is 13 events total, which is far too few to interpret, but it is the reason the guideline recommendation is framed around symptoms and function rather than survival.
STEP-HFpEF — semaglutide. 529 patients with HFpEF and BMI ≥30, semaglutide 2.4 mg weekly versus placebo for 52 weeks. KCCQ-CSS improved 16.6 points versus 8.7 (difference 7.8), body weight fell 13.3% versus 2.6%, six-minute walk distance improved 21.5 m versus 1.2 m, and CRP dropped 43.5% versus 7.3%. Serious adverse events were lower on semaglutide — 13.3% versus 26.7% (PMID 37622681).
STEP-HFpEF DM repeated it in 616 patients who also had type 2 diabetes: KCCQ-CSS +13.7 versus +6.4, weight −9.8% versus −3.4%, six-minute walk +14.3 m, serious adverse events 17.7% versus 28.8% (PMID 38587233).
Read together, the pattern is consistent and modest in the right way: large, reproducible improvements in how patients feel and function, a real reduction in heart-failure events in the one trial powered to see them, and no demonstrated mortality benefit in this population. The separate Class IIa Level A recommendation for GLP-1 receptor agonists in type 2 diabetes rests on a much larger outcomes base, including SELECT's 20% relative reduction in major adverse cardiovascular events — 6.5% versus 8.0%, HR 0.80 (95% CI 0.72–0.90) — across 17,604 patients with overweight or obesity and established cardiovascular disease but no diabetes (PMID 37952131).
What this changes in the research-compound market
Practically, three things.
Attention on these two specific molecules gets another leg. Guideline inclusion is how a compound moves from "weight-loss drug" to "cardiometabolic standard of care" in prescriber behaviour, and prescriber behaviour has historically influenced brand-side supply and pricing cycles for the approved products. Reported market commentary has linked past shortage cycles to shifts in interest elsewhere in the market. Current research-market vendor pricing is tracked in the semaglutide buying guide and the tirzepatide buying guide.
The doses in the guideline are the trial doses, not community doses. SUMMIT ran tirzepatide titrated up to 15 mg weekly. STEP-HFpEF ran semaglutide at 2.4 mg weekly. Both are the standard obesity-indication ceilings, reached by slow titration over months, in patients under cardiology supervision with echocardiography, NT-proBNP and functional testing at baseline. Community protocols routinely differ from both the dose and the monitoring. Our documentation of the published titration schedules is in the semaglutide dosing guide and the tirzepatide dosing guide.
Nothing here says anything about the compounds one step down the pipeline. Retatrutide, cagrilintide and the rest of the next-generation column have no guideline standing anywhere, and the guideline process cannot reach them until they are approved.
