Randomised, placebo-controlled trial of carvedilol in patients with congestive heart failure due to ischaemic heart disease

Background In patients with heart failure, P-blocker therapy improves left-ventricular function after 3-6 months of treatment, but effects of such treatment on symptoms and exercise performance are inconsistent, and the longer-term effects on death and other serious clinical events remain uncertain. We have investigated these issues in a doubleblind, placebo-controlled, randomised trial of the P-adrenergic blocker carvedilol (which also has a,-blocking properties). Methods 415 patients with chronic stable heart failure were randomly assigned treatment with carvedilol (207) or matching placebo (208). At baseline, 6 months, and 12 months, we measured left-ventricular ejection fraction, leftventricular dimensions, treadmill exercise duration, 6 min walk distance, New York Heart Association (NYHA) class, and specific activity scale (SAS) score. Double-blind followup continued for an average of 19 months, during which all deaths, hospital admissions, and episodes of worsening heart failure were documented. Findings After 12 months, left-ventricular ejection fraction had increased by 5.3% (2

CHARITY: Chagas cardiomyopathy bisoprolol intervention study: a randomized double-blind placebo force-titration controlled study with Bisoprolol in patients with chronic heart failure secondary to Chagas cardiomyopathy [NCT00323973]

BACKGROUND: Chagas' disease is the major cause of disability secondary to tropical diseases in young adults from Latin America, and around 20 million people are currently infected by T. cruzi. Heart failure due to Chagas cardiomyopathy is the main clinical presenation in Colombia. Heart failure due to Chagas' disease may respond to digoxin, diuretics and vasodilator therapy. Beta-adrenoreceptor antagonism seems to protect against the increased risk of cardiac arrhythmia and sudden death due to chronic sympathetic stimulation. The aim of this study is to evaluate the effects of the selective beta-adrenergic receptor blocker Bisoprolol on cardiovascular mortality, hospital readmission due to progressive heart failure and functional status in patients with heart failure secondary to Chagas' cardiomyopathy. METHODS/DESIGN: A cohort of 500 T. cruzi seropositive patients (250 per arm) will be selected from several institutions in Colombia. During the pretreatment period an initial evaluation visit will be scheduled in which participants will sign consent forms and baseline measurements and tests will be conducted including blood pressure measurements, twelve-lead ECG and left ventricular ejection fraction assessment by 2D echocardiography. Quality of life questionnaire will be performed two weeks apart during baseline examination using the "Minnesota living with heart failure" questionnaire. A minimum of two 6 minutes corridor walk test once a week over a two-week period will be performed to measure functional class. During the treatment period patients will be randomly assigned to receive Bisoprolol or placebo, initially taking a total daily dose of 2.5 mgrs qd. The dose will be increased every two weeks to 5, 7.5 and 10 mgrs qd (maximum maintenance dose). Follow-up assessment will include clinical check-up, and blood collection for future measurements of inflammatory reactants and markers. Quality of life measurements will be obtained at six months. This study will allow us to explore the effect of beta-blockers in chagas' cardiomyopathy