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 .
Growth hormone treatment in dilated cardiomyopathy.
Treatment with human recombinant growth hormone ( GH ) has yielded conflicting results in patients with congestive heart failure . We analyzed the baseline somatotrophic axis in 50 patients with dilated cardiomyopathy . Then , a double-blind , r and omized , placebo-controlled study of GH was performed . We r and omly allocated these patients to treatment with subcutaneous GH ( 2 IU daily ) or placebo for a minimum of 12 weeks . The primary end-points were the effect on left ventricular ( LV ) mass and systolic wall stress . The secondary endpoint was LV ejection fraction . Severity of heart failure as determined by cardiac index , LV end-diastolic diameter , and plasma noradrenaline concentrations correlated markedly with baseline serum insulin-like growth factor-1 ( IGF-1 ) levels . Patients in the GH group had an increase in LV mass compared with the placebo group ( p = 0.0001 ) . There was no significant difference in LV systolic wall stress , mean blood pressure , or systemic vascular resistance between the two groups . New York Heart Association ( NYHA ) functional classification and distance in 6-minute walk test remained unchanged . The change in IGF-1 concentrations between GH and placebo group was notably related ( p = 0.0001 ) to the change in LV mass ( p = 0.0001 ) . The GH-induced increase of IGF-1 predicted the changes of ejection fraction ( p < 0.05 ) . A marked increase of ejection fraction of 7 % was observed in patients whose IGF-1 increased by more than the median increase , in comparison to the patients with an increase below the median ( p = 0.03 ) . Serum levels of IGF-1 reflecting GH secretion are diminished in relation to severity of heart failure in patients with dilated cardiomyopathy . GH-induced increases of IGF-1 of more than 80 pg/mL caused notable improvement of ejection fraction . There is a marked increase in LV mass in patients with dilated cardiomyopathy given GH . Changes in LV mass are related to changes in serum IGF-1 concentrations
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 .