 The purpose of this study is to evaluate the lung Doppler signals in left HF patients with and without pulmonary congestion i.e. decompensated left HF patients and compensated left HF patients respectively, in comparison to a control group of subjects without CHF non-CHF controls, in order to determine the diagnostic value of this non-invasive method in CHF. If this method will prove to be of diagnostic value, it could potentially be used to diagnose and monitor CHF patients in both inpatient and outpatient settings. 