Metoprolol reverses left ventricular remodeling in patients with asymptomatic systolic dysfunction: the REversal of VEntricular Remodeling with Toprol-XL (REVERT) trial.

BACKGROUND: There are no randomized, controlled trial data to support the benefit of beta-blockers in patients with asymptomatic left ventricular systolic dysfunction. We investigated whether beta-blocker therapy ameliorates left ventricular remodeling in asymptomatic patients with left ventricular systolic dysfunction. METHOD AND RESULTS: Patients with left ventricular ejection fraction <40%, mild left ventricular dilation, and no symptoms of heart failure (New York Heart Association class I) were randomly assigned to receive extended-release metoprolol succinate (Toprol-XL, AstraZeneca) 200 mg or 50 mg or placebo for 12 months. Echocardiographic assessments of left ventricular end-systolic volume, end-diastolic volume, mass, and ejection fraction were performed at baseline and at 6 and 12 months. The 149 patients randomized to the 3 treatment groups (200 mg, n=48; 50 mg, n=48; and placebo, n=53) were similar with regard to all baseline characteristics including age (mean, 66 years), gender (74% male), plasma brain natriuretic peptide (79 pg/mL), left ventricular end-diastolic volume index (110 mL/m2), and left ventricular ejection fraction (27%). At 12 months in the 200-mg group, there was a 14+/-3 mL/m2 decrease (least square mean+/-SE) in end-systolic volume index and a 6+/-1% increase in left ventricular ejection fraction (P<0.05 versus baseline and placebo for both). The decrease in end-diastolic volume index (14+/-3) was different from that seen at baseline (P<0.05) but not with placebo. In the 50-mg group, end-systolic and end-diastolic volume indexes decreased relative to baseline but were not different from what was seen with placebo, whereas ejection fraction increased by 4+/-1% (P<0.05 versus baseline and placebo). CONCLUSION: Beta-blocker therapy can ameliorate left ventricular remodeling in asymptomatic patients with left ventricular systolic dysfunction.

Risk factors for Helicobacter pylori resistance in the United States: the surveillance of H. pylori antimicrobial resistance partnership (SHARP) study, 1993-1999.

BACKGROUND: Pretreatment antimicrobial resistance has an important impact on the efficacy of many Helicobacter pylori treatment regimens. OBJECTIVE: To estimate the prevalence of H. pylori resistance to antimicrobials in the United States, to characterize risk factors associated with H. pylori antimicrobial resistance, and to explore the association between drug utilization and antimicrobial resistance patterns over time. DESIGN: Meta-analysis using patient-level data. SETTING: 20 nationwide trials of H. pylori eradication. PATIENTS: 3624 men and women, each of whom contributed one isolate. MEASUREMENTS: Rates of H. pylori resistance to clarithromycin, metronidazole, and amoxicillin, according to geographic region, age, sex, study year, ethnicity, ulcer status, test method, and study. RESULTS: Overall resistance to clarithromycin, metronidazole, and amoxicillin was 10.1% (95% CI, 9.1% to 11.1% [360 of 3571 patients]), 36.9% (CI, 35.1% to 38.7% [1063 of 2883 patients]), and 1.4% (CI, 1.0% to 1.8% [48 of 3486 patients]), respectively. In multivariable analyses, multiple risk factors were associated with resistance to individual agents. Clarithromycin resistance was significantly associated with geographic region (P = 0.050), older age (P < 0.001), female sex (P < 0.001), inactive ulcer disease (P < 0.001), and study (P = 0.010). Metronidazole resistance was significantly associated with female sex (P < 0.001), earlier year of study enrollment (P = 0.036), Asian ethnicity (P < 0.001), use of an epsilometer test (P = 0.002), and study (P < 0.001). Amoxicillin resistance was low and was not significantly associated with any risk factor. In the 1990s, when rates for use of oral macrolides and metronidazole were relatively stable, clarithromycin resistance rates were stable and metronidazole resistance rates varied. CONCLUSIONS: Clinicians should consider risk factors for antimicrobial resistance when deciding which patients should have susceptibility testing and when choosing appropriate H. pylori treatments in the empirical setting.