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 .
Effect of carvedilol on survival in severe chronic heart failure.
BACKGROUND Beta-blocking agents reduce the risk of hospitalization and death in patients with mild-to-moderate heart failure , but little is known about their effects in severe heart failure . METHODS We evaluated 2289 patients who had symptoms of heart failure at rest or on minimal exertion , who were clinical ly euvolemic , and who had an ejection fraction of less than 25 percent . In a double-blind fashion , we r and omly assigned 1133 patients to placebo and 1156 patients to treatment with carvedilol  for a mean period of 10.4 months , during which st and ard therapy for heart failure was continued . Patients who required intensive care , had marked fluid retention , or were receiving intravenous vasodilators or positive inotropic drugs were excluded . RESULTS There were 190 deaths in the placebo group and 130 deaths in the carvedilol group . This difference reflected a 35 percent decrease in the risk of death with carvedilol ( 95 percent confidence interval , 19 to 48 percent ; P=0.00013 , unadjusted ; P=0.0014 , adjusted for interim analyses ) . A total of 507 patients died or were hospitalized in the placebo group , as compared with 425 in the carvedilol group . This difference reflected a 24 percent decrease in the combined risk of death or hospitalization with carvedilol ( 95 percent confidence interval , 13 to 33 percent ; P<0.001 ) . The favorable effects on both end points were seen consistently in all the subgroups we examined , including patients with a history of recent or recurrent cardiac decompensation . Fewer patients in the carvedilol group than in the placebo group withdrew because of adverse effects or for other reasons ( P=0.02 ) . CONCLUSIONS The previously reported benefits of carvedilol with regard to morbidity and mortality in patients with mild-to-moderate heart failure were also apparent in the patients with severe heart failure who were evaluated in this trial
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 .