4D Flow Cardiac MR in Primary Mitral Regurgitation

Area of Science:

• Cardiovascular Imaging
• Medical Physics
• Cardiac Surgery

Background:

• Four-dimensional-flow cardiac MR (4DF-MR) shows promise for assessing primary mitral regurgitation.
• The correlation between 4DF-MR-derived mitral regurgitant volume (MR-Rvol) and post-operative left ventricular (LV) reverse remodeling remains unestablished.

Purpose of the Study:

• To determine if 4DF-MR-derived MR-Rvol correlates with LV reverse remodeling in primary mitral regurgitation.

Main Methods:

• Prospective observational study involving 44 patients with moderate primary mitral regurgitation.
• Utilized 5T/Balanced steady-state free precession (bSSFP) sequence/Phase contrast imaging/Multishot echo-planar imaging pulse sequence.
• Assessed MR-Rvol using 4DF-MR, phase-contrast MR (PMRI), and transthoracic echocardiography (TTE), correlating with post-operative LV end-diastolic volume index (LVEDVi) changes.

Main Results:

• 4DF-MR and PMRI showed narrower limits of agreement for MR-Rvol compared to TTE.
• A significant association was found between MR-Rvol (quantified by PMRI and 4DF-MR) and post-operative LVEDVi decrease (P < 0.05).
• 4DF-MR exhibited the highest diagnostic performance for predicting LVEDVi reduction (AUC 0.83).

Conclusions:

• 4DF-MR is a valuable tool for assessing primary mitral regurgitation.
• The study establishes a correlation between 4DF-MR-derived MR-Rvol and LV reverse remodeling.
• 4DF-MR demonstrates significant clinical utility in managing patients with mitral regurgitation.