Table 2.

Detailed study characteristics

Author, year	Study name	Primary outcome(s)	Secondary outcome(s)	Funding	Centers	Location	Transmission frequency	Audible or active alert	Type of alert	Treatment protocol	Type of monitoring system	Implantable device(s)	Proprietary systems
Abraham, 2016	CHAMPION	Rate of HF hospitalizations at 6 months, Freedom From a Device/System-related Complication (DSRC) at 6 months, Freedom From Pressure Sensor Failure at 6 months	Change from baseline in pulmonary artery mean pressure at 6 months, proportion of patients hospitalized for heart failure at 6 months, days alive outside of the hospital at 6 months, quality of life—Minnesota Living With Heart Failure Questionnaire (MLHFQ) at 6 months	St. Jude	Multicenter	USA	Daily		Clinician	Hemodynamic-guided care strategy (optivolemic—no change, hypervolemic—increase in diuretics and reevaluation in 2–3 days, hypovolemic—decrease diuretic/liberalization of oral fluid/salt restriction)	Wireless pulmonary artery pressure sensor	Wireless PA pressure sensor	CardioMEMS
Adamson, 2011	REDUCEhf	HF events (HF hospitalizations, or ED/unplanned clinic visits with IV therapy)	All-cause mortality or HF hospitalizations, CV events, all events, intracardiac pressure, NYHA class, 6MWT	Medtronic	Multicenter	USA	Weekly		Clinician	Variable (clinician-directed)	RV pressure/estimated PA diastolic pressure measurement using implantable hemodynamic monitoring-ICD	ICD	Chronicle
Bohm, 2016	OptiLink HF	Composite of all-cause mortality and CV hospitalization	All-cause mortality, CV mortality, composite of all-cause mortality and HF hospitalizations, CV hospitalizations, HF hospitalizations, all-cause hospitalizations	Medtronic	Multicenter	Germany	Variable (based off fluid index threshold crossing—programmed at investigators discretion)	x	Clinician	Variable (clinician-directed)	Thoracic impedance measurements (OptiVol) with automated threshold-based clinician alerts	ICD or CRT-D	OptiVol, CareLink
Boriani, 2017	MORE CARE	Composite of all-cause mortality and CV and device-related hospitalization	CV hospitalizations or CV ED visits, HF hospitalizations, device-related hospitalizations, outpatient visits	Medtronic	Multicenter	Europe/Israel	Variable (based off fluid index threshold crossing—programmed at investigators discretion)	x	Clinician	Variable (clinician-directed)	Thoracic impedance measurements (OptiVol), atrial tachyarrhythmias with automated threshold-based clinician alerts	CRT-D	OptiVol, CareLink
Bourge, 2008	COMPASS-HF	HF hospitalization (or requiring IV therapy)	Composite of all-cause hospitalization, emergency department, and urgent care visits; hospital-free days at 6 months; clinical worsening based on NYHA class or death; MLWHF; 6MWT	Medtronic	Multicenter	USA	Weekly (at least weekly)		Clinician	Variable (clinician-directed)	RV pressure/estimated PA diastolic pressure measurement using implantable hemodynamic monitoring-ICD or CRT-D (Chronicle)	Implantable right ventricular pressure monitoring system	Chronicle
Domenichini, 2016	LIMIT-CHF	HF hospitalization	Composite of all-cause hospitalization, emergency department, and unscheduled clinic visits; NYHA class; MLWHF; 6MWT	Medtronic, St. Jude	Single	UK	Variable (based off fluid index threshold specific to ICD- or CRT-D-based monitor)	x	Patient	Diuretic dose increased by 50% for 1 week	Thoracic impedance measurements (OptiVol or CorVue) with automated threshold-based patient alerts	ICD or CRT-D	OptiVol, CorVue, CareLink, Merlin.net PCN
Hindricks, 2014	IN TIME	Composite of all-cause mortality, CV hospitalization, and worsening NYHA class	Mortality, HF hospitalizations	Biotronik	Multicenter	Europe/Australia/Israel	Daily or on detection of tachyarrhythmia		Clinician	Variable	Tachyarrhythmia monitoring and alerts with impedance-measurement capabilities	ICD or CRT-D	n/a
Landolina, 2012	EVOLVO	ED or unscheduled clinic visits for HF, arrhythmia, ICD-related event	ED visit for HF, ED visit for arrhythmia or ICD-related event, composite of ED, clinic visit or HF/arrhythmia/ICD hospitalization	Medtronic, Italian Ministry of Health	Multicenter	Italy	Daily		Clinician	Variable (clinician-directed: adjust medical therapy/bring to clinic if needed)	Thoracic impedance measurements (OptiVol) with automated threshold-based clinician alerts	ICD or CRT-D	OptiVol, CareLink
Luthje, 2015	N/A	First HF hospitalization	Mortality, ventricular tachyarrhythmia requiring ICD-shock	Medtronic	Single	Germany	Variable (based off fluid index threshold crossing—programmed at 60 Ω)	x	Clinician	If positive alert and signs of clinical decompensation: hospital admission. If positive alert and no decompensation: increase diuretic dose by 50% and daily weights	Thoracic impedance measurements (OptiVol) with automated threshold-based clinician alerts	ICD or CRT-D	OptiVol, CareLink
Morgan, 2017	REM HF	Composite of all-cause mortality and CV hospitalization	All-cause mortality, CV mortality, non-CV mortality, composite of CV mortality and CV hospitalization	Medtronic, British Heart Foundation	Multicenter	UK	Weekly		Clinician	Variable; however clinicians instructed to value parameter trends rather than single value changes	Thoracic impedance, ventricular arrhythmias, activity, heart rate variability, device therapy (no threshold/alerts)	ICD or CRT-D	n/a
Van Veldhuisen, 2011	DOT-HF	Composite of all-cause mortality and HF hospitalization	All-cause mortality, HF hospitalizations, unscheduled outpatient visits, OptiVol alert for clinically relevant event	Medtronic	Multicenter	Europe/Asia/Africa/Middle East	Variable (based off fluid index threshold specific to ICD- or CRT-D-based monitor)	x	Patient	Variable (clinician-directed)	Thoracic impedance measurements (OptiVol) with automated threshold-based patient alerts; HRV, arrhythmia, activity (Cardiac Compass) available for review at outpatient visits	ICD or CRT-D	OptiVol, Cardiac Compass

HF heart failure, CV cardiovascular, ED emergency department; IV intravenous, NYHA New York Heart Association, ICD implantable cardioverter-defibrillator, 6MWT 6-min walk test, CRT-D cardiac resynchronization therapy-defibrillator, MLHFQ Minnesota Living With Heart Failure Questionnaire