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 .
Beta-blockade in heart failure: a comparison of carvedilol with metoprolol.
OBJECTIVES This study was performed to compare the long-term clinical efficacy of treatment with metoprolol versus carvedilol in patients with chronic heart failure . BACKGROUND Beta-adrenergic blockade is of proven value in chronic heart failure .  Metoprolol , a selective beta-blocker , is widely used , but recent trials suggest carvedilol , a nonselective beta-blocker with alpha-1-receptor antagonist activity and antioxidant activities , is also effective . It is uncertain , however , if these additional properties of carvedilol provide further clinical benefit compared with metoprolol . METHODS In this r and omized double-blind control trial , 51 patients with chronic heart failure and mean left ventricular ( LV ) ejection fraction of 26 % + /- 1.8 % were r and omly assigned treatment with metoprolol 50 mg twice daily or carvedilol 25 mg twice daily in addition to st and ard therapy after a four-week dose titration period for a total of 12 weeks . Response was assessed by a quality of life question naire , New York Heart Association class , exercise capacity ( 6-min walk test ) , radionucleotide ventriculography for LV ejection fraction , two-dimensional echocardiography measurement of LV dimensions and diastolic filling and 24-h electrocardiograph monitoring to assess heart rate variability . RESULTS Both carvedilol and metoprolol produced highly significant improvement in symptoms ( p < 0.001 ) , exercise capacity ( p < 0.05 ) and LV ejection fraction ( p < 0.001 ) , and there were no significant differences between the two drugs . Carvedilol had a significantly greater effect on sitting and st and ing blood pressure , LV end-diastolic dimension and normalized the mitral E wave deceleration time . CONCLUSIONS Both metoprolol and carvedilol were equally effective in improving symptoms , quality of life , exercise capacity and LV ejection fraction , although carvedilol lowers blood pressure more than metoprolol
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 .