heart failure with new york heart association (nyha) classification ii or iii

chronic kidney disease

cardiac ejection fraction <40%

on heart failure therapy including an acei or arb, and a bb

willing to understand and comply with study procedures and provide written informed consent.

hospitalization within 4 weeks of baseline visit

history or presence of gastrointestinal conditions such as severe constipation or gastrointestinal tract strictures

current or anticipated dialysis during study

in the investigator's judgment, any cardiovascular, renal, hepatic, endocrine, gastrointestinal, neurological, or other disease or condition that makes the subject's study participation unsafe

drug or alcohol abuse