The 2026 GLP-1 heart failure guidelines changed the conversation, not the whole treatment plan. Europe's cardiology society now says semaglutide or tirzepatide should be considered for some people who have symptoms, obesity, and a heart squeeze measurement of at least 45%. The recommendation is meaningful, but it is not a blanket instruction and it does not replace a cardiologist's care.
GLP-1 is a gut hormone involved in appetite and blood sugar. Semaglutide copies its signal; tirzepatide also acts on GIP, another gut hormone.
What changed in the 2026 GLP-1 heart failure guidelines
As of September 9, 2026, the day this article was written, the European Society of Cardiology's new heart-failure guideline, published August 28, gives semaglutide or tirzepatide a Class IIa, Level B1 recommendation for a defined group. The actual recommendation table says they should be considered for people with symptomatic heart failure, left-ventricular ejection fraction of at least 45%, and body mass index of at least 30, whether or not they have diabetes. The goal named in the table is to reduce body weight and improve exercise capacity and quality of life.
Left-ventricular ejection fraction, or LVEF, is the percentage of blood the heart's main pumping chamber pushes out with each beat. Body mass index, or BMI, is a height-to-weight screening number.
The ESC announcement dated August 28 calls this one of the guideline's important treatment changes. Five weeks earlier, on July 23, the American College of Cardiology published an expert pathway that also placed semaglutide and tirzepatide among options for carefully selected people with HFpEF and obesity. That U.S. document is expert guidance, not a new drug-label indication.
Class IIa means consider it, not prescribe it automatically
A Class IIa recommendation is a well-supported option. In plain language, the panel believes the evidence leans toward benefit and clinicians should consider the treatment. The words are not "everyone should receive it."
Level B1 describes the strength of the evidence. On the ESC's revised evidence scale, B1 means suggestive but not conclusive evidence, usually from at least one adequately powered randomized trial. A randomized trial assigns people by chance to treatment or comparison groups, which makes the comparison more reliable.
The grade also tells the reader what remains unsettled. A cardiologist still has to decide whether the heart-failure diagnosis fits, whether obesity is part of the problem, and whether the likely gains outweigh the risks for that person.
Why semaglutide and tirzepatide are both named
The guideline rests on three main studies. STEP-HFpEF studied semaglutide in people with HFpEF and obesity without diabetes. STEP-HFpEF DM studied a similar group who also had type 2 diabetes. Both followed symptoms, physical limits, walking capacity, and weight for one year.
HFpEF means heart failure with preserved ejection fraction: the squeeze can look near normal, yet the heart does not fill and handle pressure normally enough to meet the body's needs. The result can be breathlessness, swelling, and tiring easily.
The SUMMIT trial tested tirzepatide in people with HFpEF and obesity. It looked at health status and also counted cardiovascular death or worsening heart-failure events. These trials explain why both medicines appear in the table, but they do not make the two drugs interchangeable.
The detailed STEP results belong in our guide to semaglutide for heart failure. The separate review of tirzepatide heart evidence covers SUMMIT and the broader cardiovascular story.
Who the recommendation covers
The shortest useful test is four lines:
| Guideline condition | What it means in ordinary language |
|---|---|
| Symptomatic heart failure | A clinician has diagnosed heart failure and symptoms are present |
| LVEF at least 45% | The heart's measured squeeze is 45% or higher |
| BMI at least 30 | The guideline's obesity threshold is met |
| Diabetes | It can be present or absent |
Meeting those lines does not settle the decision. Breathlessness and ankle swelling can come from lung disease, kidney disease, medication effects, or other heart conditions. An echocardiogram, an ultrasound picture of the heart, helps with the diagnosis but is not the whole assessment.
The recommendation also does not apply to someone merely at risk of heart failure, or to every person taking a GLP-1 for weight management. It is written for people who already have symptomatic heart failure and meet the other thresholds.
What the guideline does not mean
A professional guideline is not a regulatory approval, a new U.S. label, or a reason to start or change medication without the clinician managing the heart failure. It adds an option to a larger plan. It does not replace the other medicines, monitoring, nutrition, movement, or fluid decisions that heart-failure care may involve.
The product distinction matters too. The STEP and SUMMIT researchers studied trial medications under controlled protocols. They did not study compounded formulations. Semaglutide and tirzepatide offered through Promise are dispensed as compounded medications, which are different from FDA-approved products: the formulations offered here are not FDA-approved. The FDA explains that it does not verify a compounded drug's safety, effectiveness, or quality before marketing.
A licensed provider may still prescribe a compounded formulation when clinically appropriate; that decision is between the patient and the doctor. The ESC guideline should not be read as evidence that a compounded product was tested for heart failure.
How this fits an existing compounded prescription
For someone already prescribed compounded semaglutide or tirzepatide for weight management, the new guideline is a reason for the prescribing clinician and cardiologist to compare notes. Heart-failure medicines, kidney function, blood pressure, diabetes treatment, and side effects all sit in the same picture.
Nausea, vomiting, or diarrhea can lead to dehydration. That matters more when heart-failure care also includes a diuretic, a medicine that helps the body release extra fluid. Any dose and monitoring decisions belong to the clinicians who can see the full medication list and recent lab results.
At Promise, a licensed provider reviews every request and not everyone qualifies. Heart failure is not a side note on that review; it can change whether a compounded prescription is appropriate and how closely the care teams need to coordinate.
What to watch next
The important next questions are narrower than the headlines: whether longer studies confirm fewer heart-failure hospital stays and deaths, how well the approach works outside trial populations, and how guidance develops for people whose ejection fraction is below the guideline's threshold.
For now, the honest reading is simple. The 2026 ESC guideline puts semaglutide and tirzepatide into the conversation for obesity-related, symptomatic heart failure with a relatively preserved squeeze. It does not make either medicine mandatory, and it leaves the individual decision with a heart-failure clinician.