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The relationship between heart rate reserve and oxygen uptake reserve in heart failure patients on optimized and non-optimized beta-blocker therapy.

Carvalho VO, Guimarães GV, Bocchi EA - Clinics (Sao Paulo) (2008)

Bottom Line: The heart rate slope for the non-optimized group was derived from the points 0.949+/-0.088 (0 intercept) and 1.055+/-0.128 (1 intercept), p<0.0001.The heart rate slope for the optimized group was derived from the points 1.026+/-0.108 (0 intercept) and 1.012+/-0.108 (1 intercept), p=0.47.Regression linear plots for the heart rate slope for each patient in the non-optimized and optimized groups revealed a slope of 0.986 (almost perfect) for the optimized group, but the regression analysis for the non-optimized group was 0.030 (far from perfect, which occurs at 1).

View Article: PubMed Central - PubMed

Affiliation: Faculdade de Medicina, Instituto do Coração, Hospital das Clínicas, Universidade de São Paulo, São Paulo, Brazil. vitor.carvalho@usp.br

ABSTRACT

Background: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients either on non-optimized or off beta-blocker therapy is known to be unreliable. The aim of this study was to evaluate the relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients receiving optimized and non-optimized beta-blocker treatment during a treadmill cardiopulmonary exercise test.

Methods: A total of 27 sedentary heart failure patients (86% male, 50+/-12 years) on optimized beta-blocker therapy with a left ventricle ejection fraction of 33+/-8% and 35 sedentary non-optimized heart failure patients (75% male, 47+/-10 years) with a left ventricle ejection fraction of 30+/-10% underwent the treadmill cardiopulmonary exercise test (Naughton protocol). Resting and peak effort values of both the percentage of oxygen consumption reserve and percentage of heart rate reserve were, by definition, 0 and 100, respectively.

Results: The heart rate slope for the non-optimized group was derived from the points 0.949+/-0.088 (0 intercept) and 1.055+/-0.128 (1 intercept), p<0.0001. The heart rate slope for the optimized group was derived from the points 1.026+/-0.108 (0 intercept) and 1.012+/-0.108 (1 intercept), p=0.47. Regression linear plots for the heart rate slope for each patient in the non-optimized and optimized groups revealed a slope of 0.986 (almost perfect) for the optimized group, but the regression analysis for the non-optimized group was 0.030 (far from perfect, which occurs at 1).

Conclusion: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in patients on optimized beta-blocker therapy was reliable, but this relationship was unreliable in non-optimized heart failure patients.

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Relationship between percentage of heart rate reserve (%HRR) and percentage of oxygen consumption reserve (%VO2R) in non-optimized heart failure patients. The plot represents stage by stage regression of the cardio-pulmonary exercise test. The dotted line is the identity line, the full line
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f2-03-cs-0146: Relationship between percentage of heart rate reserve (%HRR) and percentage of oxygen consumption reserve (%VO2R) in non-optimized heart failure patients. The plot represents stage by stage regression of the cardio-pulmonary exercise test. The dotted line is the identity line, the full line

Mentions: The %VO2R was strongly related to the %HRR in optimized and non-optimized patients analyzed stage-by-stage during the cardiopulmonary exercise test (r=0.95, p<0.0001 with 9.3 of residual SD and r=0.91, p<0.0001 with 12.7 of residual SD, respectively). The mean regression line coincided with the line of identity in the optimized beta-blocker therapy group (p=0.31), but this relationship was not observed in non-optimized patients (p=0.012) (Figures 1 and 2).


The relationship between heart rate reserve and oxygen uptake reserve in heart failure patients on optimized and non-optimized beta-blocker therapy.

Carvalho VO, Guimarães GV, Bocchi EA - Clinics (Sao Paulo) (2008)

Relationship between percentage of heart rate reserve (%HRR) and percentage of oxygen consumption reserve (%VO2R) in non-optimized heart failure patients. The plot represents stage by stage regression of the cardio-pulmonary exercise test. The dotted line is the identity line, the full line
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2664269&req=5

f2-03-cs-0146: Relationship between percentage of heart rate reserve (%HRR) and percentage of oxygen consumption reserve (%VO2R) in non-optimized heart failure patients. The plot represents stage by stage regression of the cardio-pulmonary exercise test. The dotted line is the identity line, the full line
Mentions: The %VO2R was strongly related to the %HRR in optimized and non-optimized patients analyzed stage-by-stage during the cardiopulmonary exercise test (r=0.95, p<0.0001 with 9.3 of residual SD and r=0.91, p<0.0001 with 12.7 of residual SD, respectively). The mean regression line coincided with the line of identity in the optimized beta-blocker therapy group (p=0.31), but this relationship was not observed in non-optimized patients (p=0.012) (Figures 1 and 2).

Bottom Line: The heart rate slope for the non-optimized group was derived from the points 0.949+/-0.088 (0 intercept) and 1.055+/-0.128 (1 intercept), p<0.0001.The heart rate slope for the optimized group was derived from the points 1.026+/-0.108 (0 intercept) and 1.012+/-0.108 (1 intercept), p=0.47.Regression linear plots for the heart rate slope for each patient in the non-optimized and optimized groups revealed a slope of 0.986 (almost perfect) for the optimized group, but the regression analysis for the non-optimized group was 0.030 (far from perfect, which occurs at 1).

View Article: PubMed Central - PubMed

Affiliation: Faculdade de Medicina, Instituto do Coração, Hospital das Clínicas, Universidade de São Paulo, São Paulo, Brazil. vitor.carvalho@usp.br

ABSTRACT

Background: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients either on non-optimized or off beta-blocker therapy is known to be unreliable. The aim of this study was to evaluate the relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients receiving optimized and non-optimized beta-blocker treatment during a treadmill cardiopulmonary exercise test.

Methods: A total of 27 sedentary heart failure patients (86% male, 50+/-12 years) on optimized beta-blocker therapy with a left ventricle ejection fraction of 33+/-8% and 35 sedentary non-optimized heart failure patients (75% male, 47+/-10 years) with a left ventricle ejection fraction of 30+/-10% underwent the treadmill cardiopulmonary exercise test (Naughton protocol). Resting and peak effort values of both the percentage of oxygen consumption reserve and percentage of heart rate reserve were, by definition, 0 and 100, respectively.

Results: The heart rate slope for the non-optimized group was derived from the points 0.949+/-0.088 (0 intercept) and 1.055+/-0.128 (1 intercept), p<0.0001. The heart rate slope for the optimized group was derived from the points 1.026+/-0.108 (0 intercept) and 1.012+/-0.108 (1 intercept), p=0.47. Regression linear plots for the heart rate slope for each patient in the non-optimized and optimized groups revealed a slope of 0.986 (almost perfect) for the optimized group, but the regression analysis for the non-optimized group was 0.030 (far from perfect, which occurs at 1).

Conclusion: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in patients on optimized beta-blocker therapy was reliable, but this relationship was unreliable in non-optimized heart failure patients.

Show MeSH
Related in: MedlinePlus