Influence of atrial fibrillation on efficacy and safety of omecamtiv mecarbil in heart failure: the GALACTIC-HF trial.

AIMS: In GALACTIC-HF, the cardiac myosin activator omecamtiv mecarbil compared with placebo reduced the risk of heart failure events or cardiovascular death in patients with heart failure with reduced ejection fraction. We explored the influence of atrial fibrillation or flutter (AFF) on the effectiveness of omecamtiv mecarbil. METHODS AND RESULTS: GALACTIC-HF enrolled patients with New York Heart Association (NYHA) Class II-IV heart failure, left ventricular ejection fraction ≤35%, and elevated natriuretic peptides. We assessed whether the presence or absence of AFF, a pre-specified subgroup, modified the treatment effect for the primary and secondary outcomes, and additionally explored effect modification in patients who were or were not receiving digoxin. Patients with AFF (n = 2245, 27%) were older, more likely to be randomized as an inpatient, less likely to have a history of ischaemic aetiology or myocardial infarction, had a worse NYHA class, worse quality of life, lower estimated glomerular filtration rate, and higher N-terminal pro-B-type natriuretic peptide. The treatment effect of omecamtiv mecarbil was modified by baseline AFF (interaction P = 0.012), with patients without AFF at baseline deriving greater benefit. The worsening of the treatment effect by baseline AFF was significantly more pronounced in digoxin users than in non-users (interaction P = 0.007); there was minimal evidence of effect modification in those patients not using digoxin (P = 0.47) or in digoxin users not in AFF. CONCLUSION: Patients in AFF at baseline were less likely to benefit from omecamtiv mecarbil than patients without AFF, although the attenuation of the treatment effect was disproportionally concentrated in patients with AFF who were also receiving digoxin.Clinical Trial Registration: NCT02929329.

Geographic variation in the treatment of acute myocardial infarction in the VALsartan In Acute myocardial iNfarcTion (VALIANT) trial.

BACKGROUND: The VALIANT trial compared the efficacy and safety of captopril, valsartan, and their combination in patients with left ventricular systolic dysfunction, heart failure, or both after acute myocardial infarction (MI). By examining this international trial population of high-risk patients, we sought to determine geographic variations in the use of 3 key treatments for MI. METHODS: We analyzed data from 14,512 high-risk patients with MI in the VALIANT trial from the 20 countries that had enrolled >100 patients. International variation in the proportion of patients receiving (1) reperfusion therapy (thrombolysis or primary percutaneous coronary intervention), (2) beta-blockers, or (3) aspirin at the time of MI was measured by using adjusted W scores. These scores correspond to the number of additional or fewer patients who received each of the therapies compared with the number expected, as estimated from multivariable regression models that account for patients' baseline characteristics. RESULTS: There was marked variation between countries in the use of reperfusion therapy (equivalent to a difference of up to 36/100 potentially eligible patients) and beta-blockers (41/100), whereas there was much less variation in the use of aspirin (13/100). CONCLUSIONS: Marked geographic variation persists in the use of standard evidence-based therapy advocated by international guidelines. Our findings have implications not only for care of patients but also for the conduct of international trials.

Previously known and newly diagnosed atrial fibrillation: a major risk indicator after a myocardial infarction complicated by heart failure or left ventricular dysfunction.

AIMS: To characterize the relationship between known and newly diagnosed atrial fibrillation (AF) and the risk of death and major cardiovascular (CV) events in patients with acute myocardial infarction (MI) complicated by heart failure (HF) and/or left ventricular systolic dysfunction (LVSD). METHODS: The VALIANT trial enrolled 14,703 individuals with acute MI complicated by HF and/or LVSD. AF was assessed at presentation and at randomization (median 4.9 days after symptom onset). Primary outcomes were risk of death and major CV events 3 years following acute MI. RESULTS: A total of 1812 with current AF (AF between presentation and randomization), 339 patients with prior AF (history of AF without current AF), and 12,509 without AF were enrolled. Patients with AF were older; had more prior HF, angina, and MI, and received beta-blockers and thrombolytics less often than those without AF. Three-year mortality estimates were 20% in those without AF, 37% with current AF, and 38% with prior AF. Compared with patients without AF, the multivariable adjusted HR of death was 1.25 (1.03-1.52; p=0.03) for prior AF and 1.32 (1.20-1.45; p<0.0001) for current AF. HR for major CV events was 1.15 (0.98-1.35; p=0.08) and 1.21 (1.12-1.31; p<0.0001). CONCLUSION: AF is associated with greater long-term mortality and adverse CV events with acute MI complicated by HF or LVSD.