Clinical trial NCT01977222: Improving Functional Capacity in Fontan Patients Through Inspiratory Muscle Training
Official title: Improving Functional Capacity in Fontan Patients Through Inspiratory Muscle Training
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Congenital Heart Disease
Single Ventricle
Lead sponsor: Boston Children's Hospital
Sponsor class: OTHER
First posted: 2013-11-06
Enrollment: 12
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: Mechanisms that typically result in increased cardiac output, such as inotropic support, increased heart rate, and decreased afterload, have a blunted effect in Fontan circulation. The "thoracic pump" is a contributor to venous return that has been largely unexplored in patients with Fontan physiology. Inspiratory muscle training can improve the performance of competitive athletes across a range of sports and can improve quality of life and functional capacity in heart failure patients, presumably by reducing inspiratory muscle fatigue and possibly by improving peripheral blood flow during exercise. One could surmise that the effects of these changes would be particularly important in the Fontan population. The investigators propose to study the effects of inspiratory muscle training on exercise and pulmonary function parameters in a cohort of adult Fontan patients.

The investigators hypothesize that a 12-week program of inspiratory muscle training with an inspiratory impedance threshold device will improve inspiratory muscle strength and endurance, and that this will translate into improved exercise performance in patients with Fontan physiology.


Eligibility criteria: Inclusion Criteria:

* 18 years of age and older
* Fontan physiology
* Undergoing cardiopulmonary stress testing
* Able to complete a previous cardiopulmonary stress test in the preceding 24 months
* Ability to comply with the inspiratory muscle training protocol
* Ability to return for repeat stress testing and pulmonary function testing 12 weeks after enrollment
* Ability to provide informed consent

Exclusion Criteria:

* Status post cardiac transplantation
* Current pregnancy or plans to become pregnant within the next 3 months (for females of childbearing potential)
* Active respiratory infection
* Active cigarette smoker
* Baseline oxygen saturation \<90% at the previous clinic visit or exercise test
* Forced expired volume in 1 s and/or vital capacity \<60% of predicted at the previous exercise test
* Cardiac surgery or catheter-based procedure in the preceding 18 months or planned surgery or catheter-based procedure within the next 3 months

Primary outcomes:
measure: Change in Peak VO2 Between Baseline and Post-inspiratory Muscle Training Measurements.
timeFrame: Baseline and after 12 weeks of training
Secondary outcomes:
measure: Change in Innocor Measurement (Inert Gas Rebreathing Method) of Cardiac Output at Peak Exercise
timeFrame: 12 weeks
measure: Change in SF-36 Health Survey Score (Physical Component Summary)
timeFrame: 12 weeks
Other outcomes:
measure: Change in Maximum Voluntary Ventilation
timeFrame: 12 weeks
measure: Change in Maximal Inspiratory Pressure
timeFrame: Baseline and after 12 weeks of training
measure: Change in Oxygen Pulse at Peak Exercise
timeFrame: 12 weeks
measure: Change in Peak Work Rate During Exercise
timeFrame: Baseline and after 12 weeks of training
measure: Change in VE/VCO2 Slope (Ratio) During Exercise
timeFrame: Baseline and after 12 weeks of training
Locations:
city: Boston
country: United States
facility: Children's Hospital, Boston
state: Massachusetts
Study officials:
affiliation: Boston Children's Hospital
name: Fred Wu, MD
role: PRINCIPAL_INVESTIGATOR
References: