Assessment of the jugular venous pressure (JVP) is an important clinical sign and correlates with right atrial (RA) pressure. A patient with heart failure (HF) typically has an elevated JVP, but in cases of dehydration JVP may be low. Assessment of the JVP is key to the management of patients with fluid overload or needing diuretics. Currently the assessment of JVP is made by the physician by direct visualization of the neck veins. However this is inaccurate, may vary between investigators and depends largely on the patient's habitus. The JVP and RA pressures may also be directly measured by catheterization (a routine during right heart catheterization), but this is an invasive procedure that is seldom performed.

A thermal movie of the external jugular vein at a specific neck position may help to measure the JVP. In this study different modalities of JVP assessment (clinical assessment, thermal image and invasive measurement) are to be compared

Patients scheduled for right heart catheterization at the Shaare Zedek Medical Center for non-study related medical indications will be approached.

Non-invasive estimates of JVP will be performed independently prior to the right heart catheterization, during the waiting period (within 2 hours) prior to catheterization. These will include up to 2min of thermal camera recording (to be analysed offline) and a physician's JVP evaluation. The angle of the patient's upper body will be 30-60°, the rotation of the neck will be optimal for filming, and the neck area may be cooled to enhance the images. Blinding to the results will be confirmed by performance with separate investigators and separate data registration. Right heart catheterization will then be performed and RA pressure will be recorded, as well as pulmonary and wedge pressures. JVP measured by physician and thermal image will be matched with invasive catheterization (the gold standard) using Bland Altman plots and Spearmann correlation and comparison between methods will be performed.

Inclusion Criteria:

1. Patients already scheduled for right heart catheterization for clinical indication
2. Age 18-90

Exclusion Criteria:

1. Local scar wound or bruise in the right side of the neck.
2. Current upper torso central venous catheterization such as a PICC line or dialysis catheter.

Patients scheduled for right heart catheterization at the Shaare Zedek Medical Center for non-study related medical indications will be approached