The ASSERT-III study aims to determine the incidence of sub-clinical (silent) atrial fibrillation (AF) among elderly patients with hypertension and at least one other risk factor for AF. This will be accomplished by monitoring with a wireless external loop monitor for 30 to 60 days.

Inclusion Criteria:

Patients will be eligible for inclusion if they meet all of the following:

1. Age ≥ 80 years

2. History of hypertension OR a blood pressure of ≥ 140/90 mmHg

3. Attending a primary care clinic, OR ambulatory resident of a chronic care facility

4. At least one of the following additional risk factors for developing AF:

   1. Diabetes
   2. Body mass index ≥ 30
   3. History of smoking
   4. Documented Obstructive sleep apnea
   5. Cardiovascular disease
   6. Heart Failure
   7. Left ventricular hypertrophy (on ECG or echocardiography)

5. Provide written informed consent

Exclusion Criteria:

1. ECG documented history of AF or atrial flutter, with an episode duration ≥ 6 minutes

2. Existing implanted pacemaker or defibrillator

3. Patients considered by the investigator to be unsuitable for study follow-up because the patient:

   1. is unreliable concerning the requirements for follow-up during the study and/or compliance with the use of the external loop recorder
   2. has a life expectancy less that the expected study duration due to concomitant disease
   3. has a condition which in the opinion of the investigator, would not allow current chronic treatment with anticoagultion -

elderly patients attending primary care clinic or ambulatory resident of a chronic care facility, with hypertension and at least one addional risk factor for developing AF.