Heart Failure
Conditions
Brief summary
Metoprolol succinate is a beta1-selective beta-blocker, becoming non-selective at higher doses, while carvedilol is non-selective. We examined whether metoprolol remained beta1-selective compared to carvedilol during dose up-titration in Class C heart failure (HF) Beta-blocker naïve patients. METHODS: Twenty-five NYHA FC II-III HF patients were randomized to carvedilol or metoprolol. Patients were studied at baseline and after 2 weeks of up-titration (metoprolol at 25, 50, 100, and 200 mg daily; carvedilol IR at 3.125, 6.25, 12.5, 25 mg and 50mg twice daily). Beta2- blockade was determined by an infusion of terbutaline at 6 mg/kg over 1 hour. Glucose and potassium levels were serially measured at baseline, every 15 minutes for the 1st hour and 30 minutes for 2nd hour post-infusion. The median area under the curve (AUC) for glucose and potassium changes were calculated.
Interventions
Sponsors
GlaxoSmithKline
University of Utah
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients eligible for the study had objective evidence of systolic dysfunction (ejection fraction ≤40%), were \>18 years of age, and were on stable optimal medical heart failure therapy excluding the use of beta-blockers within the previous 30 days.
Exclusion criteria
* . Patients were excluded for active viral myocarditis; hemodynamically significant valvular heart disease; hypertrophic cardiomyopathy, peripartum cardiomyopathy; contra-indications to beta-blockers (asthma or obstructive airway disease requiring scheduled bronchodilators or inhaled steroids), resting heart rate \<55; supine blood pressure \<85/50; second or third degree heart block); concomitant use of beta-agonists, beta-antagonists, or anti-arrhythmics; unstable angina; myocardial infarction or bypass surgery within 3 months; or significant renal insufficiency (creatinine \>2.5 mg/dL), liver disease (transaminase levels \> 3 fold above laboratory normal), or anemia.
Countries
United States
Outcome results
None listed