Microcirculation and Vascular Function After Fontan Surgery

NCT ID: NCT05683067

Last Updated: 2023-07-20

Basic Information

• Recruitment Status: UNKNOWN
• Total Enrollment: 75 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2023-05-12
• Study Completion Date: 2024-10-01

Brief Summary

Fontan Surgery is done for children with only one working lower chamber of the heart called the 'Single Ventricle'. This surgery involves making connections between the two big veins that drain oxygen deficient blood to the heart and the lung artery directly. Fontan patients may develop long-term complications such as reduced heart function or oxygen levels, increased pressure in the veins, liver or kidney problems etc. The reasons for these complications are poorly understood. The small blood vessels in the body or 'microcirculation' are tiny (can be seen only by microscope) and they supply food and oxygen to the tissues. Very little is known about what happens to the microcirculation in adult Fontan survivors . In this study the investigator want to understand why these adult Fontan survivors develop complications by looking at their microcirculation and comparing them with healthy people and those who were operated for other congenital heart diseases. The study will be conducted in East Midlands Congenital Heart Centre, Glenfield Hospital.

Leicester.

Detailed Description

In normal heart, there are two working lower chambers where one chamber pumps the blood to the lungs and other chamber pumps the blood to the body. However, some congenital heart conditions have only one working lower chamber of the heart called the 'Single Ventricle'. This condition is often associated with hole between the heart chambers with increased or decreased blood flow to the lungs. This can lead to mixing of blood in the heart with low oxygen levels in the body. The surgery for single ventricle is usually performed in stages starting from the infancy. Fontan surgery is the last stage where the two big veins that return the blood to the heart is connected to the lung artery directly. This surgery improves the oxygen levels in the blood and lessens the burden on the single ventricle. The blood is not pumped to the lungs by the heart but rather enters passively to the lungs through this new surgical connection. Some people operated for Fontan surgery have many short-term and long-term complications such as increased pressure in veins , poor heart function and low oxygen levels in the blood. In particular, the organs below the chest such as kidney, liver and gut are affected, and all of these predict poor outcomes. The reason for these complications are poorly understood.

The small blood vessels in the body or 'microcirculation' are very tiny and are less than 150 microns in diameter. These includes arterioles, capillaries, and venules. Very little is known about the microcirculation in adult Fontan survivors and its association with aortic stiffness, late complications, and quality of life. In this study, The investigators want to look at the blood vessels in adult Fontan survivors, people operated for other congenital heart diseases, and healthy volunteers using a special microscope called Hand Held Capillary Microscopy. The investigators will visualize their blood vessel appearance, number, and size they have in their hands, feet, and under the tongue. This procedure is non-invasive and will not cause any pain. The aortic stiffness will be measured non-invasively using a special blood pressure monitor called Mobile 'O' Graph, which is about size of a pocket diary. 24 hour blood pressure monitoring is optional. The investigator will also collect the information about the quality of life using questionnaires as few studies have shown that the quality of life is affected in adult Fontan survivors and it was associated with poor vascular function. Age matched healthy controls and adults survivors of other congenital heart surgeries will also undergo these tests for comparison purpose. This study will be conducted at East Midlands Congenital Heart Centre, Glenfield Hospital, Leicester.

Conditions

Congenital Heart Disease

Study Design

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

Study Groups

Fontan Survivors

The investigator will include Fontan survivors between 16-50 years of age for the study.

Hand Held Capillary Microscopy

Intervention Type: OTHER

The investigator will visualize the blood vessel appearance, number, and size they have in their hands, feet, and under the tongue. This procedure is non-invasive and will not cause any pain.

Mobile 'O' Graph

Intervention Type: OTHER

The aortic stiffness will be measured non-invasively using a special blood pressure monitor called Mobile 'O' Graph, which is about size of a pocket diary. 24 hour blood pressure monitoring is optional.

quality of life using questionnaires

Intervention Type: OTHER

The investigator will evaluate the quality of life using questionnaires such as EQ-5D-5L questionnaire and the Minnesota Living with Heart Failure Questionnaire (MLHFQ)

People operated for congenital heart diseases

The investigator will include people operated for other types of congenital heart diseases such as tetralogy of Fallot, transposition of great arteries between 16 and 50 years of age

Hand Held Capillary Microscopy

Intervention Type: OTHER

The investigator will visualize the blood vessel appearance, number, and size they have in their hands, feet, and under the tongue. This procedure is non-invasive and will not cause any pain.

Mobile 'O' Graph

Intervention Type: OTHER

The aortic stiffness will be measured non-invasively using a special blood pressure monitor called Mobile 'O' Graph, which is about size of a pocket diary. 24 hour blood pressure monitoring is optional.

quality of life using questionnaires

Intervention Type: OTHER

The investigator will evaluate the quality of life using questionnaires such as EQ-5D-5L questionnaire and the Minnesota Living with Heart Failure Questionnaire (MLHFQ)

Healthy volunteers

The investigator will include healthy volunteers between 16 to 50 years of age for comparison purpose.

Hand Held Capillary Microscopy

Intervention Type: OTHER

The investigator will visualize the blood vessel appearance, number, and size they have in their hands, feet, and under the tongue. This procedure is non-invasive and will not cause any pain.

Mobile 'O' Graph

Intervention Type: OTHER

The aortic stiffness will be measured non-invasively using a special blood pressure monitor called Mobile 'O' Graph, which is about size of a pocket diary. 24 hour blood pressure monitoring is optional.

quality of life using questionnaires

Intervention Type: OTHER

The investigator will evaluate the quality of life using questionnaires such as EQ-5D-5L questionnaire and the Minnesota Living with Heart Failure Questionnaire (MLHFQ)

Interventions

Hand Held Capillary Microscopy

The investigator will visualize the blood vessel appearance, number, and size they have in their hands, feet, and under the tongue. This procedure is non-invasive and will not cause any pain.

Intervention Type: OTHER

Mobile 'O' Graph

The aortic stiffness will be measured non-invasively using a special blood pressure monitor called Mobile 'O' Graph, which is about size of a pocket diary. 24 hour blood pressure monitoring is optional.

Intervention Type: OTHER

quality of life using questionnaires

The investigator will evaluate the quality of life using questionnaires such as EQ-5D-5L questionnaire and the Minnesota Living with Heart Failure Questionnaire (MLHFQ)

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Patients operated for Fontan procedure or other congenital heart conditions
• Patients ≥ 16 - 50 years of age
• Participant/Parents/Guardian or legal representative willing and able to give Informed Consent for participation in the study
• Able (in the Investigators opinion) and willing to comply with all study requirements

Exclusion Criteria

• Low blood pressure (90/60 mmHg with symptoms or on intravenous inotropes for maintenance of blood pressure)
• Raynaud's disease
• Autoimmune diseases
• Down's syndrome as they have lower risk for vascular anomalies compared with the general population and may have different microvasculature
• Treatment with sympathomimetic drugs
• Atrial fibrillation or any other arrhythmia which might interfere with vascular function assessments.
• Documented peripheral vascular disease
• Skin disorders such as psoriasis or significant eczema
• Any other significant disease or disorder which, in the opinion of the Investigator, may either put the participants at risk because of participation in the study, or may influence the result of the study, or the participant's ability to participate in the study.
• Tremor or Inability to keep the hand still for 20 minutes.

Note: Patients treated with angiotensin converting enzyme inhibitors or angiotensin receptor inhibitors, beta blockers, vasodilators, diuretics and digoxin will be included in the study as the majority of Fontan survivors are taking one or more of these drugs for optimization of their circulation or for symptom management. Patients treated with anticoagulants and antiplatelets will be included in the study.

• Minimum Eligible Age: 16 Years
• Maximum Eligible Age: 50 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Leicester

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Glenfield Hospital Leicester

Leicester, Leicestershire, United Kingdom

Site Status: RECRUITING

Countries

United Kingdom

Facility Contacts

Rajendra Raghuraman, MSc

Role: primary

rpr4@le.ac.uk

07838025043

Frances Bu'Lock, MD

Role: backup

frances.bulock@uhl-tr.nhs.uk

0116 256 3904

Other Identifiers

0860

Identifier Type: -

Identifier Source: org_study_id