NCT05643404

Effects of Isolated LBBB on Maximal Functional Capacity

Effects of Isolated Left Bundle Branch Block on Maximal Functional Capacity

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 162 (actual)
• Sponsor: Fundación para la Investigación del Hospital Clínico de Valencia · Academic / Other
• Sex: All
• Age: 18 Years – 90 Years
• Healthy volunteers: Accepted

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

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	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.
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

Timeline

• Start date: 2022-12-22
• Primary completion: 2024-07-09
• Completion: 2024-07-09
• First posted: 2022-12-08
• Last updated: 2024-08-21

Locations

1 site across 1 country: Spain