Non-invasive Estimation of Pulmonary Artery Pressure in Healthy Subjects by Electrical Impedance Tomography

Study Overview
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Brief Summary
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Pulmonary hypertension (PH) is a condition characterized by a sustained elevation in pulmonary artery pressure (PAP) above 25 mmHg assessed by right heart catheterization. PH is fatal in absence of adequate treatment or therapy, as the condition progressively increases the workload of the right heart and ultimately leads to its failure. With a minimal indicative prevalence of 1 case/300, PH affects at least 25'000 people in Switzerland alone. After initiation of PH therapy, the follow-up of the patient's health status is often limited to punctual PAP measurements at the clinic at intervals of several months. The lack of more frequent measurements of the patient's PAP strongly hinders the identification of short-term trends in pulmonary hemodynamics, and therefore the anticipation of worsening conditions or treatment inefficiency. As possible solutions, wireless implantable hemodynamic monitors such as the CardioMEMSTM HF System (CardioMEMS Inc., Atlanta, USA) have recently been introduced for the continuous monitoring of PAP in patients with PH. The benefits of frequent measurements over intermittent clinic visits have been demonstrated in several previous studies, notably in terms of prediction of therapy outcomes, anticipation of worsening heart failure, feedback rapidity during therapy, or decline in hospitalization rates. Nevertheless, despite the undeniable advantages that implantable monitors offer to the patient, they remain highly invasive solutions. In contrast, noninvasive alternatives for the measurement of PAP exist, such as transthoracic echocardiography, but are impractical for frequent PAP assessments due to their dependency on qualified personnel to perform the measurement. An optimal PAP monitoring modality for patients with PH should be non-invasive (free of any risks or complications associated with cardiac catheterization) and unsupervised (able to operate without supervision of a medical doctor). Such a modality does not currently exist. In the present study, the investigators propose and investigate the potential of a novel non-invasive, continuous and unsupervised PAP monitoring approach based on the pulse wave velocity (PWV) principle and the use of electrical impedance tomography (EIT).

Official Title
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Prospective Proof-of-concept Study Non-invasive Estimation of Pulmonary Artery Pressure in Healthy Subjects by Electrical Impedance Tomography

Conditions
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Pulmonary Artery Pressure

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy subjects ≥ 18 years old, BMI < 30 kg/m2 Good understanding of written and oral German Willing to provide a signed informed consent Exclusion Criteria: Pace-maker/ ICD Chronic heart diseases Chronic pulmonary diseases Congenital heart/pulmonary diseases Instable angina pectoris Active alcohol or drug abuse Pregnancy or lactation (women of childbearing age will be asked to performed urinary pregnancy test before the screening phase)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation coefficients | Assessment of significant subject-wise correlation coefficients between the reference PAP, obtained by the gold Standard transthoracic echocardiography technique, and an EIT-derived PAP-related parameter. The primary outcome is therefore the demonstration of the feasibility of monitoring changes in PAP (intra-subject trending ability) by EIT. | Single visit 2 hours |