tool for helping pa­ tients whose predominant problem was edema. The success of diuretics masked the fact that their use may often be hemodynamically unsound and that they may reduce cardiac output. Only many years after their introduction has the use of diuretics found its appropriate place. Hemodynamic monitoring has gone via the same path. The great contribu­ tion of continuous bedside hemodynamic measurements to understanding heart failure resulted in over-usage by many clinicians, who found themselves treating hemodynamic charts rather than patients. It took almost a decade to realize that hemodynamic improvement, even in the chronic setting, does not necessarily mean symptomatic improvement or an increase in exercise capac­ ity.