Algorithm Using LINQ Sensors for Evaluation And Treatment of Heart Failure

Inclusion Criteria: * Patient has NYHA Class II or III heart failure per most recent assessment, irrespective of left ventricular ejection fraction (LVEF) * Patient has documented recent history of symptomatic heart failure, defined as meeting any one of the following three criteria: 1. Hospital admission with primary diagnosis of HF within the last 12 months, OR 2. Intravenous HF therapy (e.g. IV diuretics/vasodilators) or ultrafiltration within the last 6 months, OR 3. Patient had the following BNP/NT-proBNP within the last 3 months: If LVEF ≥ 50%, then BNP\> 150 pg/ml or NT-proBNP \> 450 pg/ml OR If LVEF is \<50%, then BNP\> 300 pg/ml or NT-proBNP \> 900 pg/ml * Patient is willing and able to comply with the protocol, including LINQ ICM insertion, CareLink transmissions (including adequate connectivity), study visits and remote care directions. * Patient is 18 years of age or older. * Patient has a life expectancy of 12 months or more. Exclusion Criteria: * Patient is currently implanted with a cardiovascular implantable electronic device (CIED) (e.g. ICM, pacemaker, ICD, CRT-D or CRT-P device) or hemodynamic monitor. * Patient is receiving temporary or permanent mechanical circulatory support. * Patient had MI or PCI/CABG within past 90 days. * Patient has had a heart transplant, or is currently on heart transplant list. * Patient has severe valve stenosis on echocardiogram. * Patient has primary pulmonary hypertension (pre-capillary, WHO group 1,3,4,5). * Patient is on chronic intravenous inotropic drug therapy (e.g. dobutamine, milrinone). * Patient has severe renal impairment (eGFR \<30 mL/min). * Patient has systolic blood pressure of \< 90 mmHg at the time of enrollment. * Patient is on chronic renal dialysis. * Patient is unable to undergo one round of PRN medication intervention (i.e. 4 days of increased diuretics dose). * Patient has liver disease, defined as AST/ALT \>5x normal, or bilirubin \>2x normal. * Patient has serum albumin \< 3 g/dL. * Patient has hypertrophic obstructive cardiomyopathy, constrictive pericarditis or amyloidosis. * Patient has complex adult congenital heart disease. * Patient has active cancer involving chemotherapy and/or radiation therapy. * Patient weighs more than 500 pounds. * Patient is pregnant or breastfeeding (all females of child-bearing potential must have a negative pregnancy test within 1 week of enrollment). * Patient is enrolled in another interventional study.