Pharmacological trials including patients with more severe heart failure were more likely to show a significant improvement with therapy than trials of milder heart failure .
Using mean values in these trials , the age of patients appeared a more important determinant of 6MWT distance than New York Heart Association classification .
The 6MWT has not yet been proven to be a robust test for the identification of effective pharmacological interventions although it appears useful for the assessment of cardiac resynchronization therapy .
The results of the 6MWT were concordant with changes in symptoms , suggesting that it may be used as supportive evidence for symptom benefit .
AIMS The 6 min walk test ( 6MWT ) is commonly used in clinical trials to assess treatments for heart failure , but its ability to distinguish between effective and ineffective treatments is question able .
The aim of this study is to investigate , using a systematic literature review , the utility of the 6MWT as a measure of the effectiveness of treatment in r and omized controlled trials of heart failure .
Safety and efficacy of carvedilol in severe heart failure. The U.S. Carvedilol Heart Failure Study Group.
BACKGROUND Many patients remain markedly symptomatic despite optimal current therapy for heart failure . Beta-blockers have often been viewed as contraindicated in this group because of their potential adverse short-term effects on cardiac function . METHODS AND RESULTS One hundred thirty-one patients with severe congestive heart failure were enrolled into a double-blind , placebo-controlled study of the vasodilating beta-blocker carvedilol .  All patients had symptomatic , advanced heart failure while on st and ard triple therapy , as evidence d by a mean ejection fraction of 0.22 , marked reduction in distance traveled in a 6-minute corridor walk test , and severe impairment in quality of life measured by the Minnesota Living With Heart Failure Question naire . After a 2-week , open-label test of 6.25 mg twice daily carvedilol , 105 patients were r and omized ( 2:1 ) to receive either carvedilol ( up to 25 mg twice daily , n = 70 ) or matching placebo ( n = 35 ) for 6 months while background therapy with digoxin , diuretics , and an angiotensin-converting enzyme inhibitor remained constant . Ten patients ( 8 % ) did not complete the open-label period because of adverse events and 11.4 % in both the carvedilol and placebo groups dropped out in the double-blind phase . The study was terminated early by the Data Safety and Monitoring Board and follow-up evaluation was therefore aborted before the projected number of patients and follow-up time was achieved . Quality of life , which was the primary endpoint , improved similarly in the carvedilol and placebo groups , whereas the global assessment by the physicians and the patient exhibited a better response to carvedilol ( P < .05 ) . Hospitalization and mortality rate were too low to evaluate a difference , and exercise time and New York Heart Association classification did not change significantly in response to the drug . Left ventricular ejection fraction rose significantly ( + 0.09 ) in the carvedilol group compared with the placebo group ( + 0.02 , P = .004 ) . CONCLUSION The beta-blocker carvedilol can be safely employed in patients with severe heart failure . Improved left ventricular function with a trend for some improvement in symptoms combined with the experience with the drug in the larger population of less severe patients in this multicenter trial suggests that carvedilol may have a favorable long-term effect in heart failure of diverse severity
Pharmacological trials including patients with more severe heart failure were more likely to show a significant improvement with therapy than trials of milder heart failure .
Using mean values in these trials , the age of patients appeared a more important determinant of 6MWT distance than New York Heart Association classification .
The 6MWT has not yet been proven to be a robust test for the identification of effective pharmacological interventions although it appears useful for the assessment of cardiac resynchronization therapy .
The results of the 6MWT were concordant with changes in symptoms , suggesting that it may be used as supportive evidence for symptom benefit .
AIMS The 6 min walk test ( 6MWT ) is commonly used in clinical trials to assess treatments for heart failure , but its ability to distinguish between effective and ineffective treatments is question able .
The aim of this study is to investigate , using a systematic literature review , the utility of the 6MWT as a measure of the effectiveness of treatment in r and omized controlled trials of heart failure .