PV Loop and Pulmonary Hypertension

Hythem Nawaytou

Status: Enrolling

Conditions: Pulmonary Vascular Resistance Abnormality

Treatments: Procedure: Measuring VA Coupling

Study type: Observational

Funder types: Other

Identifiers

NCT05484596

PEDS-2020-29351

Details and patient eligibility

About

The right ventricular (RV) systolic function is a key determinant of outcome in patients with pulmonary hypertension and elevated pulmonary vascular resistance. As the pulmonary artery pressure and vascular resistance increase (i.e. RV afterload) in these patients, so does the right ventricular contractility in an attempt to maintain cardiac output. This is response of a ventricle to its afterload is termed ventriculo-arterial (VA) coupling. However, there is a limit to this increase in contractility after which VA uncoupling occurs ultimately leading to decrease cardiac output and right ventricular failure. The accepted gold standard for measurement of VA coupling is the ratio of the end systolic ventricular elastance (Ees) to the end systolic arterial elastance (Ea) measured invasively via high fidelity conductance catheters during cardiac catheterization. In this study, the aim is to devise a non-invasive scoring system that can identify VA uncoupling in patients with elevated pulmonary vascular resistance using echocardiography, cardiac MRI, cardiopulmonary exercise testing and brain natriuretic peptide levels. The hypothesis is that a group of morphologic and functional variables obtained noninvasively can differentiate an RV with VA coupling from that with VA uncoupling.

Enrollment: 65 estimated patients

Sex: All

Ages: 1 to 21 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Children 1-21 years of age
• Patients referred for cardiac catheterization for hemodynamic evaluation due to concern for pulmonary hypertension
• Structurally normal heart

Exclusion criteria

• Pulmonary hypertension secondary to pulmonary venous hypertension defined as pulmonary capillary wedge pressure of more than or equal to 15mmHg
• Pulmonary hypertension secondary to mixed pulmonary arterial and venous hypertension
• Patient will be excluded from performing an MRI if they have:

claustrophobia, metal implants or allergy to contrast

• Patients will be excluded from performing a cardiopulmonary exercise test (CPET) if they are: 1) less than 8 years or 2) unable to follow instructions to run on a treadmill.

Trial design

65 participants in 1 patient group

Observational Group

Description:

Subjects will undergo clinically indicated investigations and tests. The research part of the study is measuring the VA coupling using high fidelity catheters. That is expected to increase the duration of the cardiac catheterization for 30 minutes.

Treatment:

Procedure: Measuring VA Coupling