Correlations between respiratory and functional variables in heart failure

Respiratory alterations can impact on the functional performance of patients with heart failure.

To correlate maximum inspiratory muscular force and lung function variables with functional capacity in heart failure patients.

A transversal study January-July 2007 with 42 chronic heart disease patients (28 males) with no prior pulmonary illness. The patients were in New York Heart Association Functional Class I, II and III. The variables used were maximum inspiratory pressure, forced vital capacity and forced expiratory volume in the first second. Respiratory variables measured were distance covered in the six-minute walk test, NYHA functional class and the physical functioning domain of the Short Form-36 Quality of Life Questionnaire.

Maximum inspiratory pressure correlated with the six-minute walk test (r=0.543 and p<0.001), functional capacity (r=-0.566 and p<0.001) and the physical functioning domain score of the Short Form- 36 (r=0.459 and p=0.002). The same was true of forced vital capacity and the six-minute walk test (r=0.501 and p=0.001), functional capacity (r=-0.477 and p=0.001) and Short Form-36 (r=0.314 and p=0.043) variables. Forced expiratory volume correlated with the distance covered in the six-minute walk test (r=0.514 and p<0.001) and functional capacity (r=-0.383 and p=0.012).

Lung function and inspiratory muscular force respiratory variables correlated with functional variables in patients with heart failure.