Noninvasive Measurement of Cardiac Output in Pulmonary Hypertension Using Inert Gas Rebreathing

Noninvasive Measurement of Cardiac Output in Pulmonary Hypertension Using Inert Gas Rebreathing

The study hypothesis is that accuracy of CO measurement by IGR does not differ from classical CO measurement methods such as thermodilution or direct Fick method. This is why the study aims to determine whether non invasive cardiac output (CO) measurement using inert gas rebreathing (IGR)is a suitable method in patients with pulmonary hypertension. In order to examine this, the IGR method will be used in patients undergoing diagnostic or follow-up right heart catheterization.

Inert Gas Rebreathing method enables non invasive measurement of cardiac output (CO) using the single rebreathing method. A mixture of blood soluble (N2O) and blood insoluble gas (SF6) and environmental air is inhaled and the amount of N2O, SF6, O2 and CO2 is measured by a photoacoustic analysator. The length of a measurement is about 1 minute.

As the gold standard measurement of CO is performed invasively, there is an urgent need for the development of non-invasive tools like IGR.

Inclusion Criteria:

• Written informed consent
• Patients who undergo right heart catheterization

Exclusion Criteria:

• Missing written informed consent