RESUMEN
A study was made of pulmonary function tests in patients averaging 2 years post MI, who did not present evidence of chronic bronchitis or other types of primary pneumopathy. The influence of smoking and moderate pulmonary congestion due to heart failure were studied. We found a significant inverse relation between dyspnea and the forced one second expiratory volume, as an expression of bronchial obstruction. There was a significant increase in the respiratory volume in patients after MI. This alteration was particularly evident in patients who smoked. On the contrary, in pulmonary congestion the tendency was towards a decrease in respiratory volume. We confirmed the importance of pulmonary function tests for the evaluation of subjective symptoms, this was confirmed by the finding of a decrease in the dynamic pulmonary volumes, specially in smokers, which demonstrates the unfavorable influence of smoking. Heart failure did not significantly influence static or dynamic parameters, although the residual functional capacity showed a tendency to decrease with the degree of congestion.