DO THESE MINIATURIZE MONITORING ELEMENTS WORK? AN OBSERVATIONAL ANALYSIS OF THE EFFECTIVENESS OF REVEAL LINQ IMPLANTS IN DETECTING CARDIAC CAUSES OF SYNCOPE IN A COMMUNITY HOSPITAL.

Background: Implantable cardiac monitors (ICM) have continued to gain acceptance since its introduction into clinical practice to help physician accurately detect cardiac causes of syncope that may need further intervention. Their cost-effectiveness in the evaluation of syncope has continued to receive positive reviews as recent guidelines have encouraged early use of this device.However, the question that every physician recommending such device has to contain with is how certain that the benefits outweigh the risks. Patient often want to know how successful this device has been in detecting cardiac causes of syncope in patients with similar presentation in their immediate community.

Purpose: With the increasing diagnosis of syncope of unknown etiology, it has become important to further look deeper as to possible causes of these repeated re-admissions on account of recurrent syncope. The ICM offers an opportunity to truly identify Cardiac causes of syncope as if undetected could lead to devastating outcomes and even sudden cardiac deaths.
The aim of this analysis is to determine if these devices have led to any appreciable detection of cardiac causes of syncope to merit its continuous use in a community based hospital like ours.

Description: The Medtronic Reveal LINQ (Medtronic, Minneapolis, Minnesota) ICM is unique in that it is smaller than its predecessor, uses wireless telemetry for remote monitoring of patients and in addition, features a new P-wave filter that refines the performance of the AF algorithm. These interesting improvements are aimed at simplifying the implantation process and thus increasing patient’s acceptance.
The device when implanted transmits data to the Medtronic’s CareLink network automatically on a daily basis and CareAlerts are sent from CareLink to physicians if one of the following conditions is detected: Patient –activated episodes, device detected tachyarrythmia, asystole, bradycardia, atrial fibrillation and even when there is a low battery or the device needs a reset.
Patients included in this retrospective cohort analysis are a total of 152 patients seen in the Cardiology clinic of Berkshire Medical Center for reasons of syncope of unclear etiology who subsequently received the Reveal LINQ implant. The analysis looked at patient from July 1st 2014 to 30th June 2017. 3 physicians accounted for the total number of implanted devices.
The analysis using SAS software revealed that 21.7% of the patients who were implanted with the Reveal LINQ insertable cardiac monitors were identified to have a cardiac cause of their syncope based on the monitoring network and have received either an Implantable Cardioverter-Defibrillator (ICD) or a pacemaker.
In actuality, 33 patients out of the 152 patients had a true cardiac etiology for their syncope and were further managed with adequate intervention. 31 of these patients received a pacemaker and only 2 received an ICD.

Conclusions: This finding is significant and calls for primary care providers and generalist to carefully identify patients presenting with recurrent syncope who may benefit from this novel cardiac monitoring device thus preventing any imminent or debilitating outcome that may be associated with undiagnosed cardiac syncope.