This is a pilot study using a novel, minimal risk, portable, hands-free oral-positive pressure device (oPEP) in patients with Fontan palliation that will examine whether using this device in both the acute and chronic phase will alter Fontan hemodynamics and create pulsatility in the Fontan circuit and thereby increasing cardiac output. This device is easy to use and poses no significant risk to human subjects. We will measure this through echocardiographic measures including pulsatility in different aspects of the Fontan circuit including IVC, hepatic veins, the Fontan conduit, and pulmonary arteries and aortic blood flow measurements. After demonstration of how to use the device appropriately, we will have patients use the device after their clinical echocardiogram for their clinic appointment. We will ask them to use the device at home 3-4 times a day for 10-15 mins and have them return in approximately 4 weeks to have another echocardiogram done with the same measurements.

This will be measured by echocardiogram using Doppler evaluation of the pulmonary artery

The Pulmonary Artery Pulsatility Index (PAPI) is calculated using Doppler-derived pulmonary artery velocities:

PAPI= (Systolic Velocity - Diastolic Velocity) /Mean Velocity

This was measured by echocardiography

Aortic Valve Velocity Time Integral (VTI) Definition: Aortic VTI is a key echocardiographic measurement reflecting stroke distance and cardiac output.

Measurement:

Obtained using pulsed-wave Doppler at the left ventricular outflow tract (LVOT) just below the aortic valve.

The VTI is measured by tracing the Doppler envelope of the LVOT flow during systole.

Clinical Importance:

Stroke Volume Calculation:

Stroke Volume = LVOT VTI × LVOT Area

Hands-free oral-positive pressure device (oPEP): This is a pilot study using a novel, minimal risk, portable, hands-free oral-positive pressure device (oPEP) in patients with Fontan palliation that will examine whether using this device in both the acute and chronic phase will alter Fontan hemodynamics and create pulsatility in the Fontan circuit and thereby increasing cardiac output. This device is easy to use and poses no significant risk to human subjects. We will measure this through echocardiographic measures including pulsatility in different aspects of the Fontan circuit including IVC, hepatic veins, the Fontan conduit, and pulmonary arteries and aortic blood flow measurements. After demonstration of how to use the device appropriately, we will have patients use the device after their clinical echocardiogram for their clinic appointment. We will ask them to use the device at home 3-4 times a day for 10-15 mins and have them return in approximately 4 weeks to have another echocardiogram done with the same measurements.

This will be measured by echocardiogram using Doppler evaluation of the pulmonary artery

The Pulmonary Artery Pulsatility Index (PAPI) is calculated using Doppler-derived pulmonary artery velocities:

PAPI= (Systolic Velocity - Diastolic Velocity) /Mean Velocity

Hands-free oral-positive pressure device (oPEP): This is a pilot study using a novel, minimal risk, portable, hands-free oral-positive pressure device (oPEP) in patients with Fontan palliation that will examine whether using this device in both the acute and chronic phase will alter Fontan hemodynamics and create pulsatility in the Fontan circuit and thereby increasing cardiac output. This device is easy to use and poses no significant risk to human subjects. We will measure this through echocardiographic measures including pulsatility in different aspects of the Fontan circuit including IVC, hepatic veins, the Fontan conduit, and pulmonary arteries and aortic blood flow measurements. After demonstration of how to use the device appropriately, we will have patients use the device after their clinical echocardiogram for their clinic appointment. We will ask them to use the device at home 3-4 times a day for 10-15 mins and have them return in approximately 4 weeks to have another echocardiogram done with the same measurements.