Chronic heart failure is becoming the main clinical
challenge in cardiology in terms of the number of patients
involved. Over the last decade, the number of patients with
this clinical syndrome has increased considerably; recent
estimations have shown that 5 million patients in the United
States have chronic heart failure, with 550,000 new patients
being diagnosed annually, resulting in over 1 million
hospitalizations (1). The diagnostic and therapeutic costs
involved are estimated to be more than $29 billion per year
(1). The major portion of these costs appears to be related