Extended ECG Monitoring in HCM Patients (EXAMINE-HCM)

Extended Ambulatory Monitoring With iRhythm Zio XT Improves Care of Patients With Hypertrophic Cardiomyopathy

The purpose of this study is to determine, among a large cohort of 300 consecutive patients with hypertrophic cardiomyopathy, if extended ambulatory monitoring using the iRhythm Technologies, Inc. Zio XT device results in identifying a greater burden of nonsustained ventricular tachyarrhythmia (nsVT) compared to current ACCF/AHA guideline recommended 48-hour monitoring.

Study Overview

• Status: Completed
• Conditions: Atrial Fibrillation; Arrhythmia; Ventricular Tachycardia; Hypertrophic Cardiomyopathy; Nonsustained Ventricular Tachycardia
• Intervention / Treatment: Device: Zio XT

Detailed Description

Optimal duration to monitor patients for identifying nsVT remains unclear. The investigators aim to determine the prevalence and burden of nsVT with longer term monitoring with the iRhythm Zio XT device over a 2-week period vs. 48 hours; and whether, this greater burden of nsVT compared to conventional shorter monitoring potentially identifies a subset of HCM patients who may be at higher risk of sudden cardiac death.

• Study Type: Observational
• Enrollment (Actual): 250

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02111
      • Tufts Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients from the hypertrophic cardiomyopathy population will be recruited.

Description

Inclusion Criteria:

• Subject must be 18 to 65 years of age at time of informed consent and must not be a member of a vulnerable population.
• Subject has been diagnosed with hypertrophic cardiomyopathy, as defined by a maximal LV wall thickness of ≥15 mm anywhere in LV wall, in absence of another cause that could be responsible for the LV hypertrophy.
• Subject eligible to receive the Zio XT device per the current approved indications for use.

Exclusion Criteria:

• Subject with pacemaker
• Known skin allergies or reaction to adhesives
• The investigator deems a condition that could limit a subject's ability or unwillingness to participate in the study, comply with study required monitoring and/or follow-up visits.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
HCM Group; Eligible HCM subjects will be monitored for arrhythmias with a 2-week ECG patch.	Device: Zio XT; ambulatory cardiac monitoring device

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total number of nsVT runs through 14 days of ambulatory cardiac monitoring, as compared to the first 48 hours.	Compare the number of nsVT runs detected between the first 48 hours vs 2 weeks of ambulatory cardiac monitoring.	14 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total number of atrial fibrillation runs through 14 days of ambulatory cardiac monitoring, as compared to the first 48 hours.	Compare the number of AF runs detected between the first 48 hours vs 2 weeks of ambulatory cardiac monitoring.	14 days
Number of clinical management decisions based on 14 days of ambulatory cardiac monitoring, as compared to the first 48 hours ambulatory cardiac monitoring.	Compare the number clinical decisions based on the first 48 hours vs 14 days of ambulatory cardiac monitoring.	14 days

Collaborators and Investigators

• Sponsor: iRhythm Technologies, Inc.
• Investigators: Principal Investigator: Martin Maron, MD, Tufts Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): January 14, 2020
• Primary Completion (Actual): April 18, 2022
• Study Completion (Actual): April 18, 2022

Study Registration Dates

• First Submitted: August 12, 2019
• First Submitted That Met QC Criteria: August 13, 2019
• First Posted (Actual): August 14, 2019

Study Record Updates

• Last Update Posted (Actual): March 1, 2023
• Last Update Submitted That Met QC Criteria: February 27, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: electrocardiogram; ECG; EKG; electrocardiography; ambulatory monitoring; mobile cardiac monitoring
• Additional Relevant MeSH Terms: Pathologic Processes; Heart Diseases; Cardiovascular Diseases; Pathological Conditions, Anatomical; Arrhythmias, Cardiac; Aortic Valve Disease; Heart Valve Diseases; Cardiac Conduction System Disease; Aortic Stenosis, Subvalvular; Aortic Valve Stenosis; Atrial Fibrillation; Tachycardia; Tachycardia, Ventricular; Hypertrophy; Cardiomyopathies; Cardiomyopathy, Hypertrophic
• Other Study ID Numbers: iRT-001-2019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No