The study primarily aims to collect standard of care clinical data in a wide spectrum of simple to complex mitral valve regurgitation (MVR) cases to validate a post-processing stand-alone software prototype (QFlow), developed by Philips Research Paris (Medisys).

Investigator does not intervene in the care of the patient, but simply collects standard of care images and measurements that are needed for the validation of the investigational software.

Inclusion Criteria:

• both genders
• age between 18 and 85 years old (adult, senior)
• sinus rhythm
• hHemodynamic stable
• mitral valve regurgitation (MVR) of any grade i.e., from mild to severe as determined by assessment of a qualifying TransThoracic Echocardiography (TTE) exam at Saint-Luc University Hospital
• scheduled for TransEsophageal Echocardiography (TEE) at Saint-Luc University Hospital, as part of the subject's routine standard of care
• subjects has functional capacity to give written informed consent

Exclusion Criteria:

• pregnancy
• subject lacks functional capacity to give written informed consent belongs to a vulnerable population per investigator's judgment or subject has any kind of disorder that compromises his/her ability to give written informed consent and/or to comply with study procedures

Among the120 subjects, there will be three (3) sub-groups as follows:

• a first sub-group (A) of 50 subjects with all inclusion criteria and none of the exclusion criteria
• a second sub-group (B) of 50 subjects with additional inclusion criterion: scheduled for cardiac Magnetic Resonance (cMR), as part of the subject's routine standard of care
• a third sub-group (C) of 20 subjects with additional inclusion criterion: scheduled for MitraClip transcatheter mitral valve repair (MitraClip) procedure as part of the subject's routine standard of care