An eighty nine year old woman has a long history of systolic heart failure that resulted in a large left ventricular infarct when she was in her 70s. She had poor activity tolerance and required assistance with activities of daily living. Even minimal activity was associated with moderately severe dyspnea and exertional chest pain, which was relieved by rest. She also exhibited marked pedal edema bilaterally. She is being treated with digitalis, furosemide (Lasix), KCl, (potassium chloride) and sublingual nitroglycerin. DQ#1: Which type of heart failure (left- or right-sided) is usually associated with dyspnea? What other clinical findings are likely to be present with this type of heart failure? DQ #2: What compensatory mechanisms are likely occurring in this patient to enhance her cardiac output? DQ#3: What is the most likely cause of this patient's pedal edema? DQ#4: What is the rationale for the use of each of the patient's medications in managing her heart disease?