Hyper-synchronicity in Hypertrophic Cardiomyopathy (HCM) : Description, Mechanism and Origin With a Multi-imaging Approach to Predict Dual Chamber Pacing Response

Not Applicable

Completed

• Conditions: Hypertrophic Cardiomyopathy; Mechanical Hyper-synchronicity
• Interventions: Procedure: Echocardiography (TEE); Device: Magnetic resonance imaging (MRI) with gadolinium enhancement; Device: Magnetic resonance imaging (MRI) without gadolinium enhancement; Procedure: 3D electrocardiographic mapping (ECM)

• Registration Number: NCT02559726
• Lead Sponsor: University Hospital, Bordeaux

Brief Summary

Hypertrophic cardiomyopathy (HCM) is a common genetic cardiovascular disease. Outflow-tract gradient of 30 mmHg or more under resting conditions is an independent determinant of symptoms of progressive heart failure and death.

The investigators hypothesize that the electrical approach by dual chamber pacing could improve symptoms and reduce outflow-tract obstruction in a specific sub-group of selected patients with a mechanical hyper-synchronicity. The aim of the study is to identify and describe this phenomenon in HCM with (O-HCM) and without (NO-HCM) outflow-tract obstruction thanks to innovative multi-imaging approach.

Detailed Description

The concept of physiological ventricular desynchrony was described recently with technics of myocardial deformation analysis applied in animal models. Authors confirmed the existence of a time delay in the contraction of the apical walls before basal walls. In O-HCM, the outflow-tract obstruction could be explained by a mechanical hyper-synchronicity between apical and basal walls. This study aims to describe the possible hyper-synchronized contraction in O-HCM and NO-HCM patients unlike the physiological desynchrony observed in healthy volunteers (HV) For this purpose, three imaging tests will be used at baseline: echocardiography (TEE), magnetic resonance imaging (MRI) with gadolinium enhancement only in HCM, and 3-dimensional electrocardiographic mapping (ECM) combined with computed tomography-scan. No follow-up is planned for this study.

Study Timeline

• Study Start: 2015-06-22
• Study First Submitted: 2015-06-26
• Study First Submitted QC: 2015-09-23
• Study First Posted: 2015-09-24
• Primary Completion: 2019-01-19
• Study Completion: 2019-01-19
• Status Verified: 2022-02
• Last Update Submitted: 2022-02-08
• Last Update Posted: 2022-02-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

• HCM: Adults aged more than 18 years with sarcomeric hypertrophic cardiomyopathy under optimal medical therapy, isolated septal hypertrophy, sinus rhythm, exploitable acoustic window. For women of childbearing age, effective contraception and required negative pregnancy test.
• O-HCM : outflow-tract gradient more than 30 mmHg at rest and during exercise
• NO-HCM : outflow-tract gradient less than 30 mmHg at rest and during exercise
• HV: Adults aged more than 18 years, without cardiovascular disease. For women of childbearing age, effective contraception and required negative pregnancy test.

Exclusion Criteria

• HV: unusable acoustic window

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
O-HCM	Echocardiography (TEE)	20 patients with Hypertrophic Cardiomyopathy with outflow-tract obstruction
NO-HCM	Echocardiography (TEE)	20 patients with Hypertrophic Cardiomyopathy without outflow-tract obstruction
NO-HCM	3D electrocardiographic mapping (ECM)	20 patients with Hypertrophic Cardiomyopathy without outflow-tract obstruction
O-HCM	3D electrocardiographic mapping (ECM)	20 patients with Hypertrophic Cardiomyopathy with outflow-tract obstruction
O-HCM	Magnetic resonance imaging (MRI) with gadolinium enhancement	20 patients with Hypertrophic Cardiomyopathy with outflow-tract obstruction
NO-HCM	Magnetic resonance imaging (MRI) with gadolinium enhancement	20 patients with Hypertrophic Cardiomyopathy without outflow-tract obstruction
healthy volunteers	Echocardiography (TEE)	20 healthy volunteers
healthy volunteers	Magnetic resonance imaging (MRI) without gadolinium enhancement	20 healthy volunteers
healthy volunteers	3D electrocardiographic mapping (ECM)	20 healthy volunteers

Primary Outcome Measures

Name	Time	Method
Mechanical time delay in contraction between basal and apical walls in TEE and MRI in O-HCM, NO-HCM and healthy volunteers	Day 1	The main interest variable is the delay value (ms) of the contraction between basal and apical walls measured by TEE and MRI.

Secondary Outcome Measures

Name	Time	Method
Delay between the beginning of the apical and basal circumferential deformation in MRI	Day 1
Electrical time delay in ECM between basal and apical walls and relationship with hyper-synchronicity and outflow tract gradient.	Day 1
Mechanical time delay between septal and lateral walls in MRI and TEE.	Day 1
Apical-basal phase on a phase analysis of the radial displacement data in MRI	Day 1
Twist angle between the base and the apex in MRI	Day 1
Relationship between each mesure with hyper-synchronicity and outflow-tract gradient	Day 1
Delay between peaks of basal and apical radial displacement in MRI	Day 1
Delay between the beginning of the apical and basal radial displacement in MRI	Day 1
Delay between apical and basal peaks circumferential strain in MRI	Day 1
Evolution of mechanical time delay between basal and apical walls at rest and exercise in O-HCM and NO-HCM and relationship with outflow-tract gradient.	Day 1

Trial Locations

Locations (1)

CHU de Bordeaux; 🇫🇷 Bordeaux, France