Most cardiovascular hospitalizations in patients with HF are related to worsening congestion and volume overload.  It is well established that congestion drives most of the typical symptoms of effort limitation, orthopnea, paroxysmal nocturnal dyspnea, and peripheral edema in HF patients.

Beyond simply making patients feel poorly, however, congestion may actually perpetuate or enhance the progression of the HF syndrome; patients with worsening filling pressures have worsening ventricular wall stress, more mitral regurgitation, secondary rises in pulmonary pressures, increased myocardial oxygen demand, and increasing load on the right ventricle – and this syndrome of progressive myocardial ischemia, worsening wall stress, and worsening pulmonary hypertension may result in progression of the biventricular dysfunction and perpetuation of a downward spiral of hemodynamic deterioration in HF.