Wearable Monitor in Patients With Syncope

Background While ECG monitoring is a reliable and established method that allows to document bradycardia in a substantial proportion of patients affected by cardioinhibitory reflex syncope, the documentation of a transient hypotension is only seldom achieved in patients affected by hypotensive syncope. Conventional ambulatory blood pressure (BP) monitoring (ABPM) has important limitations due to the short period of monitoring (usually 24-48 hours) and the intermittent nature of BP measurements (usually every 15-20 min).

The main purpose of this study is to assess the reliability of a new patient's self-administered wearable watch-type BP monitor in detecting episodes of hypotensive (pre)syncope. Secondary aim regards the estimation of feasibility of this tool.

Method The study is a prospective intrapatient comparison during tilt testing between BP measured by mean of a wearable watch-type BP monitor (Omron HeartGuide 6410T, Omron Healthcare, Kyoto, Japan) and by mean of the standard methods for continuous finger BP monitoring (Finometer®, Finapres Medical Systems, Enchede, The Netherlands, and Task Force® monitor, CNSystem, Graz, Austria), based on the photoplethysmographic volume clamp method .

Study design BP values observed during tilt testing baseline and at the time of impeding syncope will be measured by mean of the HeartGuide device and will be compared with the standard of reference of BP. BP will be recorded at rest at baseline, shortly after upright in tilting position (at stabilization), at the time of occurrence of impeding syncope (presyncope) or, alternatively at the time of maximum hypotensive effect, if syncope will not occur, and finally in the recovery period at the end of the test after returning in supine position.

Inclusion criteria

• Consecutive patients,
• >18 years of age, referred for tilt testing because affected by suspected reflex syncope

Exclusion criteria

• Arrhythmias or the inability of HeartGuide to measure BP supine at rest.