DOBUTAMINE-INDUCED CHANGES IN PULMONARY-ARTERY PRESSURE IN PATIENTS WITH CONGESTIVE-HEART-FAILURE AND THEIR RELATION TO ABNORMALITIES OF LUNG DIFFUSING-CAPACITY

The hemodynamic effects of the inotropic agent dobutamine have been ex tensively described. Several studies have invariably reported an incre ase in cardiac index and a decrease in systemic vascular resistance du ring dobutamine infusion in patients with congestive heart failure.(1- 6) Contrasting effects of dobutamine on pulmonary circulation have bee n reported with some studies showing a decrease,(1,3,5) no changes,(7- 9) or even an increase(10) in pulmonary artery (PA) pressure. However, these studies have been performed on small groups of patients, and av erage responses, not individual responses, have been usually reported. These limitations may probably explain the discordant. results obtain ed in the different studies. The goal of this study was to assess the effects of a short-term dobutamine infusion on PA pressure in a relati vely large group of patients with congestive heart failure. Furthermor e, in an attempt to understand the different responses of PA pressure in some patients compared with others, despite similar systemic respon se, the potential role of resting lung function, a known indicator of pulmonary circulation abnormalities in these patients,(11) was analyze d.