The heart and the lungs are strictly integrated both mechanically and
functionally in what is now called the cardiopulmonary unit [1-4]. As
a consequence, an abnormality of either component of this cardiopulmon
ary unit quickly alters the physiology of the other. In fact, right ve
ntricular dysfunction and failure secondary to lung disease (i.e. cor
pulmonale) are well known; on the other hand the impairment of lung fu
nction induced by left heart failure seems obvious, but the knowledge
of its pathophysiological mechanism is still incomplete. In this artic
le we will review the structural and functional changes induced by con
gestive heart failure on the lungs, their relation to the hemodynamic
abnormalities and response to therapeutic interventions.