LUX-Dx TRENDS Evaluates Diagnostics Sensors in Heart Failure Patients Receiving Boston Scientific's Investigational ICM System.

Key Inclusion Criteria:

• Patient is currently in NYHA Class II or III.

• For patients with LVEF >40% measured on most recent available echocardiographywithin the previous 12 months:

• ONE (1) of the following echocardiography findings: LA width (diameter) >3.8cm, LA length >5.0 cm, LA area >20 cm2, LA volume >55 ml, LA volume index >29ml/m2, LVH defined by septal thickness or posterior wall thickness of >1.1 cmAND

• ONE (1) of the following: Elevated BNP/NT-proBNP as defined by: BNP >100 pg/mlor NT-proBNP >300 pg/ml within the previous 90 days for patients not in atrialfibrillation or BNP >300 pg/ml or NT-proBNP >900 pg/ml for patients in atrialfibrillation at the time of screening for eligibility OR Documented heartfailure hospitalization or unscheduled heart failure IV therapy in the previous 12 months

• For patients with LVEF <40% (for MI patients, measured no less than 30 days post-MI)on most recent available echocardiography within the previous 12 months:

• ONE (1) of the following: Elevated BNP/NT-proBNP as defined by BNP >150 pg/mlor NT-proBNP >600 pg/ml within the previous 90 days for patients not in atrialfibrillation or BNP >450 pg/ml or NT-proBNP >1800 pg/ml for patients in atrialfibrillation at the time of screening for eligibility OR Documented heartfailure hospitalization or unscheduled heart failure IV therapy in the previous 12 months

• Patient is willing to be monitored in LATITUDE Clarity and use the ICM patientmobile app.

• Patient is of legal age to give informed consent and is willing to participate inthe trial.

Key Exclusion Criteria:

• Patient is currently implanted with any other active electronic medical device.

• Patient has undergone a heart transplant.

• Patient is currently enrolled in another investigational study (excludingregistries) without prior written approval from Boston Scientific.

• Patient is known to be pregnant at the time of enrollment or plans to becomepregnant during study participation.

• Patient is diagnosed with amyloidosis or hypertrophic cardiomyopathy.