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Effect of Ivabradine on Exercise Capacity After Heart Transplantation

Phase 4
Conditions
Transplanted Heart Complication
Cardiac Allograft Vasculopathy
Interventions
Drug: Placebo
Registration Number
NCT03405831
Lead Sponsor
Finn Gustafsson
Brief Summary

This study evaluates whether treatment with ivabradine compared to placebo can improve exercise capacity in long-term heart transplant recipients with cardiac allograft vasculopathy and elevated heart rate at rest.

Patients will receive treatment with either ivabradin or placebo for a period of 12 weeks.

Detailed Description

Elevated resting heart rate (HR) is a normal finding after successful heart transplantation (HTx) due to parasympathetic denervation at the operation.

Elevated resting HR is generally acknowledged as a negative predictor of outcome in heart disease. The impact in heart transplant recipients is not fully understood, however, it has been associated with increased risk of developing cardiac allograft vasculopathy (CAV) or death.

Cardiac allograft vasculopathy is a diffuse vascular disease affecting the entire coronary tree. It is the leading cause of death in patients more than 5 years after HTx and it is well known that patients with CAV have markedly reduced exercise capacity.

The association between elevated HR and CAV raises the question whether an intervention to specifically lower HR could improve symptoms and prognosis in heart transplant recipients with CAV and elevated resting HR.

Small studies have shown that HR reduction using the If channel blocker ivabradine after HTx is safe. However, none of these studies were randomized or blinded, and as such proof of any efficacy (beyond HR reduction) after HTx is non-existing. Clearly, there is a need to determine if such treatment could improve exercise capacity, graft function and prognosis after HTx.

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
35
Inclusion Criteria
  • Patients > 1 year post heart transplantation
  • CAV verified by coronary angiography or intravascular ultrasound
  • Resting HR > 80 bpm
  • Age > 18 years
  • Signed informed consent

Women, who have not yet entered menopause (defined as no menstrual bleeding in the last 12 months), will be required to provide a negative urine human chorionic gonadotropin (hCG) before entering the study and must use a safe birth control method in the total study period.

Exclusion Criteria
  • Rejection (>H1R) < 3 months
  • Severe renal failure (estimated glomerular filtration rate (GFR) < 30 mL/min/1.73 m2)
  • Inability or contraindication to perform a VO2 max test
  • Presence of any condition that might per se influence exercise performance
  • Known contraindication for treatment with ivabradine
  • Hypersensitivity to the active substance or to any of the excipients of either study drug

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PlaceboPlaceboStudy participants in this arm will receive placebo bid for a period of 12 weeks.
IvabradineIvabradineStudy participants in this arm will receive ivabradin 5 mg bid for a period of 12 weeks.
Primary Outcome Measures
NameTimeMethod
ΔVO2maxThe VO2max is assessed at baseline and 12 weeks follow-up.

The change in VO2max (ΔVO2max) (mL/kg/min) from baseline to 12 weeks follow-up. The peak oxygen uptake (VO2max) reflects the maximal ability of a person to take in, transport and use oxygen, and it defines the functional aerobic capacity. It is used to provide an overall assessment of exercise capacity.

Secondary Outcome Measures
NameTimeMethod
ΔQOL KCCQ12 weeks

Change in QOL score evaluated by Kansas City Cardiomyopathy Questionnaire from baseline to 12 weeks follow-up

ΔQOL EQ-5D-5L12 weeks

Change in QOL score evaluated by EQ-5D-5L questionnaire from baseline to 12 weeks follow-up

ΔHRrest12 weeks

Change in resting HR (beats/min) from baseline to 12 weeks follow-up

ΔHRreserve12 weeks

Change in HR reserve (beats/min) from baseline to 12 weeks follow-up

ΔLVmass12 weeks

Change in left ventricular (LV) mass (g) evaluated by cardiac MRI from baseline to 12 weeks follow-up

ΔLVEF12 weeks

Change in left ventricular ejection fraction (LVEF) (%) evaluated by cardiac MRI from baseline to 12 weeks follow-up

Δmitral deceleration time12 weeks

Change in mitral decelaration time (ms) evaluated by echocardiography from baseline to 12 weeks follow-up

ΔE/é12 weeks

Change in E/é evaluated by echocardiography from baseline to 12 weeks follow-up

ΔE/A ratio12 weeks

Change in E/A ratio evaluated by echocardiography from baseline to 12 weeks follow-up

Δisovolumetric relaxation time12 weeks

Change in isovolumetric relaxation time (ms) evaluated by echocardiography from baseline to 12 weeks follow-up

Δtransmitral flow rate12 weeks

Change in transmitral flow rate (volume/min) evaluated by cardiac MRI from baseline to 12 weeks follow-up

Δpulmonary venous flow12 weeks

Change in pulmonary venous flow (volume/min) evaluated by cardiac MRI from baseline to 12 weeks follow-up

ΔLVEDV12 weeks

Change in LVEDV (left ventricular end diastolic volume) (ml) evaluated by cardiac MRI from baseline to 12 weeks follow-up

ΔLVESV12 weeks

Change in LVESV (left ventricular end systolic volume) (ml) evaluated by cardiac MRI from baseline to 12 weeks follow-up

ΔLV peak filling rate12 weeks

Change in left ventricular (LV) peak filling rate (volume/min) evaluated by cardiac MRI from baseline to 12 weeks follow-up

Δtime to peak filling12 weeks

Change in time to peak filling (sec) evaluated by cardiac MRI from baseline to 12 weeks follow-up

Trial Locations

Locations (1)

Department of Cardiology, Copenhagen University Hospital, Rigshospitalet

🇩🇰

Copenhagen, Denmark

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