What happened
- Nature Medicine published on November 8, 2026 two papers from the CAMEO-SEMA trial on semaglutide in heart failure with preserved ejection fraction (HFpEF) and obesity.
- In the main trial, with Barry Borlaug and Milton Packer among the authors, 81 patients (47 women) received semaglutide 2.4 mg weekly or placebo for 52 weeks.
- Pulmonary artery wedge pressure during exercise, a direct measure of congestion, fell 9.8 mmHg with semaglutide and rose 0.9 with placebo; the difference was 10.6 mmHg.
- The second paper is a cardiac magnetic resonance substudy of 49 participants.
Why it matters
Semaglutide improves symptoms in HFpEF, but the mechanism was unclear. Measuring the pressure inside the heart with a catheter, at rest and during exercise, shows the drug reduces the congestion that causes breathlessness.
The magnetic resonance study complements the finding with a possible mechanism: improvements in left atrial function and ventricular filling that accompany the drop in pressure.
The number
53.7% versus 7.4%. That is the share of patients who reached hemodynamic remission, defined as normal pulmonary pressure at rest and during exercise at 52 weeks, with semaglutide and with placebo. The odds ratio was 14.1, with a very wide confidence interval (3.0 to 134.6) because of the sample size.
Context
At baseline, resting pressure was 17.5 mmHg and exercise pressure 31.7. With semaglutide, resting pressure fell 7.1 mmHg more than with placebo, and the difference was statistically significant (P < 0.0001).
In the magnetic resonance substudy, 33 participants received semaglutide and 16 placebo. The drug improved left atrial reservoir strain (+5.7%) and early ventricular filling rate (+0.64 per second). Both changes were associated with lower exercise pressures: correlations of −0.46 and −0.65.
The numbers come from the papers’ abstracts. Both are small, single-drug, 52-week trials, so they do not allow conclusions on clinical events such as hospitalizations.
At Mamífero we have followed heart and metabolic trials. Guiding statins with a coronary scan gave the same events with fewer prescriptions, Chagas: ten metabolite combinations predict which cases will damage the heart, three servings of whole-fat dairy did not harm cholesterol and Roche tests RO3903, a KRAS G12C inhibitor.
What’s next
- Larger trials that measure hospitalizations and mortality, not only pressures, are still missing.
- It remains to be seen whether the effect holds beyond 52 weeks.
- The magnetic resonance authors relate the changes to the pressures but do not prove causality.
Bottom line
Measuring the pressure inside the heart gives a direct view of how semaglutide acts in HFpEF. What is missing is whether that improvement translates into fewer hospitalizations.
Sources
- Borlaug, B. A., Jensen, M. D., Packer, M. et al., “Hemodynamic effects of semaglutide in individuals with heart failure with preserved ejection fraction and obesity: a placebo-controlled randomized clinical trial”, Nature Medicine, November 8, 2026, DOI 10.1038/s41591-026-04762-3, link.
- Ghanbari, F., Reddy, Y. N. V., Packer, M. et al., “Effects of semaglutide on cardiac structure and function in heart failure with preserved ejection fraction and obesity: a pre-specified cardiac magnetic resonance substudy of the CAMEO-SEMA trial”, Nature Medicine, November 8, 2026, DOI 10.1038/s41591-026-04787-8, link. Both notes are based on the abstracts.
- Cover image: RWhitwam, CC BY-SA 4.0, via Wikimedia Commons
Edited by Rodrigo Cornejo. How we select and verify: who writes these notes.
