Conduction System Pacing vs Biventricular Resynchronization Therapy in Systolic Dysfunction and Wide QRS: CONSYST-CRT. (CONSYST-CRT)

Conduction System Pacing vs Biventricular Resynchronization Therapy in Systolic Dysfunction and Wide QRS: CONSYST-CRT Randomized Clinical Trial.

Conduction system pacing vs biventricular resynchronization therapy in systolic dysfunction and wide QRS (CONSYST-CRT randomized clinical trial) is a non-inferiority trial that aims to study the composite endpoint consisting of all-cause mortality, cardiac transplant, heart failure hospitalizations, and left ventricular ejection fraction (LVEF) improvement <5 points.

Study Overview

• Status: Active, not recruiting
• Conditions: Resynchronization Therapy; Conduction System Pacing
• Intervention / Treatment: Device: Conduction system pacing; Device: Biventricular pacing

Detailed Description

To date, studies have shown that conduction system pacing could get similar clinical and echocardiographic responses to those obtained with biventricular therapy.

This study will randomize 130 patients to a strategy of biventricular pacing versus conduction system pacing.

CONSYST-CRT study will analyze the following parameters in the 2 groups: left ventricular ejection fraction, ventricular volumes, echocardiographic response (>=15% decrease in left ventricular end-systolic volume), NYHA functional class, heart failure hospitalization, all-cause mortality, cardiac transplant, QRS shortening, echocardiographic asynchrony (septal flash).

Clinical, electrocardiographic, echocardiographic follow-up will be performed for 1 year.

The first 70 patients have been recruited in the context of the LEVELAT study (ClinicalTrials.gov Identifier: NCT04054895)

• Study Type: Interventional
• Enrollment (Actual): 130
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Lluís Mont, MD, PhD; Phone Number: +34 93 2271778; Email: lmont@clinic.cat

Study Locations

• Spain
  • Barcelona, Spain
    • Lluís Mont

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• The patient must indicate their acceptance to participate in the study by signing an informed consent document.
• The patient must be ≥ 18 years of age.
• Left bundle branch block, QRS ≥130 and LVEF <=35%. No indication of stimulation for AV block.
• Non-left bundle branch block, QRS ≥150 and LVEF <=35%.
• Patients with indication of resynchronization therapy for ventricular dysfunction (LVEF <40%) and indication of cardiac pacing for AV block.
• LVEF <=35% in NYHA class III or IV if they are in atrial fibrillation and have intrinsic QRS >=130 ms, provided a strategy to ensure biventricular capture is in place.

Exclusion Criteria:

• Myocardial infarction, unstable angina or cardiac revascularization during the previous 3 months.
• Pregnancy.
• Participating currently in a clinical investigation that includes an active treatment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Conduction system pacing; Pacing the His-Purkinje system. Crossover to biventricular pacing was allowed in case of failed conduction system pacing: failed His bundle pacing and failed Left bundle branch pacing (high thresholds (>3.5V / 1ms); no left bundle branch pacing criteria; no left bundle branch correction). Electrocardiographic optimization allowed in order to obtain the narrowest QRS.	Device: Conduction system pacing; Lead placed in the His-Purkinje system in order to achieve QRS shortening.
Active Comparator: Biventricular pacing; Pacing from the right ventricular and coronary sinus leads. Electrocardiographic optimization with fusion-optimized intervals. Crossover from biventricular pacing to conduction system pacing will be allowed in the following situations: coronary sinus cannot be cannulated; no lateral or posterolateral branches; or phrenic stimulation.	Device: Biventricular pacing; Lead is placed in a tributary of the coronary sinus.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Composite end-point: all-cause mortality, cardiac transplant, heart failure hospitalization, and left ventricular ejection fraction (LVEF) improvement <5 points.	Non inferiority margin 10%.	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in left ventricular ejection fraction.	Non inferiority margin 2.5%	6 months; 12 months
Change in left ventricular end-systolic volume.	Non inferiority margin 3%	6 months; 12 months
Echocardiographic response (>=15% decrease in left ventricular end-systolic volume).	Non inferiority margin 10%	6 months; 12 months
Hospitalization due to heart failure, mortality or cardiac transplant (combined endpoint)	Non inferiority margin 10%	6 months; 12 months
QRS shortening	Non inferiority margin 12ms	Post-implantation (Electrophysiology Lab)
Correction of septal flash	Non inferiority margin 0.5mm	15 days; 6 months; 12 months
Change in NYHA functional class	NYHA functional class I, II, III, IV.	6 months; 12 months

Collaborators and Investigators

• Sponsor: Hospital Clinic of Barcelona
• Investigators: Study Director: Lluís Mont, MD, PhD, Hospital Clinic of Barcelona; Principal Investigator: Jose M Tolosana, MD, PhD, Hospital Clinic of Barcelona; Principal Investigator: Margarida Pujol Lopez, MD, Hospital Clinic of Barcelona

Study record dates

Study Major Dates

• Study Start (Actual): January 17, 2022
• Primary Completion (Estimated): July 1, 2024
• Study Completion (Estimated): October 1, 2024

Study Registration Dates

• First Submitted: December 19, 2021
• First Submitted That Met QC Criteria: January 7, 2022
• First Posted (Actual): January 12, 2022

Study Record Updates

• Last Update Posted (Actual): August 18, 2023
• Last Update Submitted That Met QC Criteria: August 16, 2023
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Keywords: Conduction system pacing; Biventricular pacing; Resynchronization Therapy
• Additional Relevant MeSH Terms: Heart Murmurs; Systolic Murmurs
• Other Study ID Numbers: CONSYST-CRT.

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.: Yes