Sixty patients with stable nonischemic HF under optimal medical therapy were included in this randomized double-blind study. Patients were randomized to TMZ (35 mg orally twice a day) or placebo for 6 months. LVEF, 6-minute walk test (6MWT), maximum O2 uptake in cardiopulmonary exercise test, different markers of metabolism, oxidative stress, and endothelial function, and quality of life were assessed at baseline and after TMZ treatment. Left ventricular peak glucose uptake was evaluated with the use of the maximum standardized uptake value (SUV) by 18-fluorodeoxyglucose positron emission tomography (18FDG-PET). Etiology was idiopathic in 85% and hypertensive in 15%. Both groups were similar in age, functional class, LVEF, and levels of N-terminal pro-B-type natriuretic peptide at baseline. After 6 months of TMZ treatment, no changes were observed in LVEF (31 卤 10% vs 34 卤 8%; P聽= .8), 6MWT (443 卤 25 m vs 506 卤 79 m; P聽= .03), maximum O2 uptake (19.1 卤 5.0 mL kg鈭? min鈭? vs 23.0 卤 7.2 mL kg鈭? min鈭?; P聽= .11), functional class (percentages of patients in functional classes I/II/III/IV 10/3753/0 vs 7/40/50/3; P聽= .14), or quality of life (32 卤 26 points vs 24 卤 18 points; P聽= .25) in TMZ versus placebo, respectively. In the subgroup of patients evaluated with 18FDG-PET, no significant differences were observed in SUV between both groups (7.0 卤 3.6 vs 8.2 卤 3.4 respectively; P聽= .47).
In patients with nonischemic HF, the addition of TMZ to optimal medical treatment does not result in significant changes of LVEF, exercise capacity, O2 uptake, or quality of life.