Left Atrium Reservoir Function Modulation in Patients With Atrial Fibrillation: Digoxin Versus Beta Blocker

University of Monastir

Status and phase: Enrolling; Phase 3

Conditions: Atrial Fibrillation; Left Atrial Rhythm

Treatments: Drug: Digoxin 0.25 mg; Drug: Bisoprolol

Study type: Interventional

Funder types: Other

Identifiers

NCT05540600

TN2022-NAT-I NS-86

Details and patient eligibility

About

ß blocker and digoxin effect on left atrium reservoir function are unknown. This is a randomized open label study to compare the effect of theses two molecules on left atrium function

Full description

Atrial fibrillation (AF) is responsible of significant morbidity and mortality. Management of signs and symptoms of heart failure generated by AF is at the center of the latest European recommendations . Mechanisms by which these symptoms are generated are very poorly understood. Heart rate control is one of the recommended strategies but remains poorly codified and generally follows the preferences and experiences of each local center. The European guidelines propose at least 4 molecules for heart rate control without emitting preferences for one molecule over the other due to the lack of robust randomized studies. Recently, a study comparing digoxin vs ß-blockers showed the superiority of digoxin in decreasing symptoms despite a comparable action on heart rate. On the other hand, the reservoir function of the left atrium (LA) has taken a central role in assessing signs of left heart failure and monitoring filling pressures . Other studies have demonstrated the association of left atrium reservoir strain with these symptoms .

It is commonly accepted that ß blockers decrease AF-related symptoms by a negative chronotropic effect thanks to their blocking action on the sympathetic system. While the action of digoxin on symptoms goes through a positive inotropic effect thanks to the increase in intracellular calcium .

However, the impact of these two molecules on the function of the left atrium has never been investigated. Our diagnostic hypothesis is that in addition to their action on heart rate, the improvement of symptoms noted by using b blockers and digoxin during the treatment of AF would go through an improvement LA reservoir function . The superiority of digoxin in the reduction of symptoms compared to ß blockers would be due to a greater improvement in reservoir function and this thanks to the increase in myocardial intracellular calcium.

Enrollment: 30 estimated patients

Sex: All

Ages: 18 to 90 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Any patient with atrial fibrillation naïve to ß-blocker and digoxin or patients followed for Atrial fibrillation and discontinued all treatment for more than a week.
• Frequency Control Strategy Decided
• Age over 18 years
• Stable hemodynamic state
• No contraindication to digoxin or ß-blocker

Exclusion criteria

• Required rhythm control strategy
• Contraindication to one of the two
• Heart rate <60 BPM
• Clearance rénale <30 ml/mn
• Pregnant or breastfeeding woman
• Persistence of a resting heart rate > 110
• Severe comorbidity with decreased life expectancy (advanced neoplasia, large stroke...)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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30 participants in 2 patient groups

Digoxin group

Experimental group

Description:

Patients will receive digoxin 0.25 mg once daily for a duration of 4 weeks

Treatment:

Drug: Digoxin 0.25 mg

beta blocker group

Experimental group

Description:

Patients will receive bisoprolol 2.5 mg or 5 m twice a day for a duration of 4 weeks. The choice of dose will depend on blood pressure (BP): If systolic BP ≥ 150 mmHG, the patient will have bisoprolol 5 mg x 2 per day, If systolic BP \< 150 mmHG, the patient will have bisoprolol 2.5 mg x 2 per day

Treatment:

Drug: Bisoprolol