Effects of Isolated LBBB on Maximal Functional Capacity

NCT ID: NCT05643404

Last Updated: 2024-08-21

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 162 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2022-12-22
• Study Completion Date: 2024-07-09

Brief Summary

Left bundle branch block (LBBB) has been commonly associated with adverse cardiovascular (CV) events, but the effect of an isolated LBBB on maximal functional capacity is not well characterized.

The study's main objective is to evaluate the effect of LBBB on maximum functional capacity.

Detailed Description

Left bundle branch block (LBBB) has been commonly associated with adverse cardiovascular (CV) events, but the effect of an isolated LBBB on maximal functional capacity is not well characterized.

The main objective of the study is to evaluate the effect of LBBB on maximum functional capacity (objectively evaluated by the maximum oxygen consumption -VO2max- at peak exercise in a cardiopulmonary stress test -CPET-) in subjects with LBBB without known cardiovascular disease and compare these data with controls without LBBB.

This is a prospective study that will be carried out in a single centre. All patients with a diagnosis of LBBB and without evidence of structural heart disease in imaging tests will be enrolled. For each candidate with LBBB, one control without LBBB and matched for age, sex, body surface area, and daily physical activity will be selected. All included subjects will undergo a CPET and echocardiography. A sample size estimation [alpha: 0.05, power: 80%, and a clinically significant VO2max difference between groups of at least 10%] of 148 subjects (74 subjects with LBBB + 74 controls) would be necessary to test our hypothesis.

Conditions

Left Bundle-Branch Block

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: PROSPECTIVE

Study Groups

Isolated LBBB

Subjects with left bundle branch block in the absence of clinically detectable heart disease

Cardiopulmonary exercise testing

Intervention Type: DIAGNOSTIC_TEST

Maximal functional capacity will be evaluated using incremental and symptom-limited cardiopulmonary exercise testing (CPET) on a bicycle ergometer, beginning with a workload of 10 W and increasing gradually in a ramp protocol at 10-W increments every 1 minute. We will define maximal functional capacity as when the patient stops pedalling because of symptoms, and the respiratory exchange ratio (RER) is ≥1.1. During exercise, patients were monitored with 12-lead electrocardiogram and blood pressure measurements every 2 minutes. Gas exchange data and cardiopulmonary variables were averages of values taken every 10 seconds. Peak oxygen consumption (PeakVO2) will be defined as the highest value of oxygen consumption during the last 20 seconds of exercise.

Echocardioghaphy

Intervention Type: DIAGNOSTIC_TEST

Doppler echocardiogram examinations were performed under resting conditions using 2-dimensional echocardiography. Left ventricular end-diastolic volume and left ventricular ejection fraction will be measured according to the European Society of Echocardiography

Matched controls without LBBB

Subjects without left bundle branch block and in the absence of clinically detectable heart disease

Cardiopulmonary exercise testing

Intervention Type: DIAGNOSTIC_TEST

Maximal functional capacity will be evaluated using incremental and symptom-limited cardiopulmonary exercise testing (CPET) on a bicycle ergometer, beginning with a workload of 10 W and increasing gradually in a ramp protocol at 10-W increments every 1 minute. We will define maximal functional capacity as when the patient stops pedalling because of symptoms, and the respiratory exchange ratio (RER) is ≥1.1. During exercise, patients were monitored with 12-lead electrocardiogram and blood pressure measurements every 2 minutes. Gas exchange data and cardiopulmonary variables were averages of values taken every 10 seconds. Peak oxygen consumption (PeakVO2) will be defined as the highest value of oxygen consumption during the last 20 seconds of exercise.

Echocardioghaphy

Intervention Type: DIAGNOSTIC_TEST

Doppler echocardiogram examinations were performed under resting conditions using 2-dimensional echocardiography. Left ventricular end-diastolic volume and left ventricular ejection fraction will be measured according to the European Society of Echocardiography

Interventions

Cardiopulmonary exercise testing

Maximal functional capacity will be evaluated using incremental and symptom-limited cardiopulmonary exercise testing (CPET) on a bicycle ergometer, beginning with a workload of 10 W and increasing gradually in a ramp protocol at 10-W increments every 1 minute. We will define maximal functional capacity as when the patient stops pedalling because of symptoms, and the respiratory exchange ratio (RER) is ≥1.1. During exercise, patients were monitored with 12-lead electrocardiogram and blood pressure measurements every 2 minutes. Gas exchange data and cardiopulmonary variables were averages of values taken every 10 seconds. Peak oxygen consumption (PeakVO2) will be defined as the highest value of oxygen consumption during the last 20 seconds of exercise.

Intervention Type: DIAGNOSTIC_TEST

Echocardioghaphy

Doppler echocardiogram examinations were performed under resting conditions using 2-dimensional echocardiography. Left ventricular end-diastolic volume and left ventricular ejection fraction will be measured according to the European Society of Echocardiography

Intervention Type: DIAGNOSTIC_TEST

Eligibility Criteria

Inclusion Criteria

• Adult >18 years old
• ECG criteria of left bundle branch block (for controls without left bundle branch block )
• Provide informed consent

Exclusion Criteria

• Inability to perform a maximal baseline exercise test;
• Structural heart disease, valve heart disease or diastolic dysfunction estimated by two-dimensional echocardiography;
• Previous ischemic heart disease, heart failure, myocardiopathy or myocarditis
• Effort angina during cardiopulmonary exercise testing (CPET);
• Any moderate pulmonary disease;
• Anaemia
• Left ventricular ejection fraction < 55%.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 90 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Fundación para la Investigación del Hospital Clínico de Valencia

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Patricia Palau, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Instituto de Investigacion Sanitaria INCLIVA

Locations

Marta Peiro

Valencia, , Spain

Countries

Spain

References

Palau P, Dominguez E, Minguez S, Nunez G, Santas E, Garcia-Conejo C, de Amo I, Marin P, Flor C, Lopez L, Ortega L, Gabaldon-Sanchez I, de la Espriella R, Sanchis J, Nunez J. Effect of left bundle branch block on maximal functional capacity in asymptomatic individuals without structural heart disease. Rev Esp Cardiol (Engl Ed). 2025 Mar 21:S1885-5857(25)00092-1. doi: 10.1016/j.rec.2025.03.001. Online ahead of print. English, Spanish.

Reference Type: DERIVED

PMID: 40122231 (View on PubMed)

Other Identifiers

2021/061

Identifier Type: -

Identifier Source: org_study_id