Mitral regurgitation in patients with heart failure and reduced ejection fraction: insights from GALACTIC-HF

Given the emerging role of transcatheter valve repair in HFrEF patients with moderate/severe secondary mitral regurgitation (MR), we evaluated the prevalence and outcomes related to MR in the GALACTIC-HF trial.

The randomized GALACTIC-HF trial compared the efficacy and safety of omecamtiv mecarbil to placebo in 8232 patients with HFrEF, with a primary composite outcome of a first HF event or cardiovascular death.

Of 7998 patients (97.2%) with baseline data on MR, 5782 (72.3%) had no MR, 970 (12.1%) had mild MR, and 1221 (15.3%) had moderate MR (only 25 had severe MR). Patients with moderate MR had a higher risk of the primary outcome than those without MR (adjusted HR 1.11; 95% CI 1.01-1.23); risk was not higher in patients with mild MR. The association between moderate MR and the primary outcome was most prominent in patients with less severe HF (milder NYHA class, higher LVEF, and lower N-terminal pro-B-type natriuretic peptide) compared to more severe HF. In adjusted analyses, MR was not associated with mortality, and the results of all analyses remained consistent after including patients with severe MR. The beneficial treatment effect of omecamtiv mecarbil versus placebo on clinical outcomes was not modified by MR. Over 80% of patients with moderate/severe MR fulfilled the broad inclusion criteria for COAPT and RESHAPE-HF2.

In GALACTIC-HF, almost 15% of patients with heart failure and reduced ejection fraction had moderate MR, which was associated with a higher risk of the primary outcome.