Impact of Blockade of Histamine H2 Receptors on Chronic Heart Failure Revealed by Retrospective and Prospective Randomized Studies Original Research Article

Objectives The goal of this work was to determine whether the blockade of histamine H2 receptors is beneficial for the pathophysiology of chronic heart failure (CHF). Background Because CHF is one of the major life-threatening diseases, we need to find a novel effective therapy. Intriguingly, our previous study, which predicts the involvement of histamine in CHF, suggests that we should test this hypothesis in patients with CHF. Methods We selected 159 patients who received famotidine among symptomatic CHF patients for the retrospective study. We blindly selected age- and gender-matched CHF patients receiving drugs for gastritis other than histamine H2 receptor blockers as a control group. For the prospective study, 50 symptomatic CHF patients were randomly divided into 2 groups. One group received famotidine of 30 mg/day for 6 months, and the other group received teprenone. Results In the retrospective study, famotidine of 20 to 40 mg decreased both left ventricular end-diastolic and end-systolic lengths (LVDd and LVDs, respectively) and the plasma B-type natriuretic peptide (BNP) levels (182 ± 21 vs. 259 ± 25 pg/ml, p < 0.05) with unaltered fractional shortening (FS). In a randomized, open-label study, compared with teprenone, famotidine of 30 mg prospectively decreased both New York Heart Association functional class (p < 0.05) and plasma BNP levels (183 ± 26 pg/ml vs. 285 ± 41 pg/ml, p < 0.05); this corresponded to decreasing both LVDd (57 ± 2 mm vs. 64 ± 2 mm, p < 0.05) and LVDs (47 ± 2 mm vs. 55 ± 2 mm, p < 0.05) with unaltered FS (15 ± 1% vs. 17 ± 1%). The frequency of readmission because of worsening of CHF was lower in the famotidine group (4% and 24%, p < 0.05). On the other hand, teprenone had no effects on CHF.